Merge branch 'jh/trace2'
authorJunio C Hamano <gitster@pobox.com>
Thu, 7 Mar 2019 00:59:56 +0000 (09:59 +0900)
committerJunio C Hamano <gitster@pobox.com>
Thu, 7 Mar 2019 00:59:56 +0000 (09:59 +0900)
A more structured way to obtain execution trace has been added.

* jh/trace2:
trace2: add for_each macros to clang-format
trace2: t/helper/test-trace2, t0210.sh, t0211.sh, t0212.sh
trace2:data: add subverb for rebase
trace2:data: add subverb to reset command
trace2:data: add subverb to checkout command
trace2:data: pack-objects: add trace2 regions
trace2:data: add trace2 instrumentation to index read/write
trace2:data: add trace2 hook classification
trace2:data: add trace2 transport child classification
trace2:data: add trace2 sub-process classification
trace2:data: add editor/pager child classification
trace2:data: add trace2 regions to wt-status
trace2: collect Windows-specific process information
trace2: create new combined trace facility
trace2: Documentation/technical/api-trace2.txt

67 files changed:
.clang-format
Documentation/technical/api-trace2.txt [new file with mode: 0644]
Makefile
builtin/am.c
builtin/checkout.c
builtin/pack-objects.c
builtin/rebase.c
builtin/receive-pack.c
builtin/reset.c
builtin/submodule--helper.c
builtin/worktree.c
cache.h
common-main.c
compat/mingw.c
compat/mingw.h
compat/win32/trace2_win32_process_info.c [new file with mode: 0644]
config.c
config.mak.uname
connect.c
editor.c
exec-cmd.c
git-compat-util.h
git.c
pager.c
read-cache.c
remote-curl.c
repository.c
repository.h
run-command.c
run-command.h
sequencer.c
sh-i18n--envsubst.c
sub-process.c
submodule.c
t/helper/test-parse-options.c
t/helper/test-tool.c
t/helper/test-tool.h
t/helper/test-trace2.c [new file with mode: 0644]
t/t0001-init.sh
t/t0210-trace2-normal.sh [new file with mode: 0755]
t/t0210/scrub_normal.perl [new file with mode: 0644]
t/t0211-trace2-perf.sh [new file with mode: 0755]
t/t0211/scrub_perf.perl [new file with mode: 0644]
t/t0212-trace2-event.sh [new file with mode: 0755]
t/t0212/parse_events.perl [new file with mode: 0644]
trace2.c [new file with mode: 0644]
trace2.h [new file with mode: 0644]
trace2/tr2_cfg.c [new file with mode: 0644]
trace2/tr2_cfg.h [new file with mode: 0644]
trace2/tr2_cmd_name.c [new file with mode: 0644]
trace2/tr2_cmd_name.h [new file with mode: 0644]
trace2/tr2_dst.c [new file with mode: 0644]
trace2/tr2_dst.h [new file with mode: 0644]
trace2/tr2_sid.c [new file with mode: 0644]
trace2/tr2_sid.h [new file with mode: 0644]
trace2/tr2_tbuf.c [new file with mode: 0644]
trace2/tr2_tbuf.h [new file with mode: 0644]
trace2/tr2_tgt.h [new file with mode: 0644]
trace2/tr2_tgt_event.c [new file with mode: 0644]
trace2/tr2_tgt_normal.c [new file with mode: 0644]
trace2/tr2_tgt_perf.c [new file with mode: 0644]
trace2/tr2_tls.c [new file with mode: 0644]
trace2/tr2_tls.h [new file with mode: 0644]
transport-helper.c
transport.c
usage.c
wt-status.c
index de1c8b5c77f7566d9e41949e5e397db3cc1b487c..41d4cd23fd97f599053a19555a173894da71e560 100644 (file)
@@ -149,7 +149,7 @@ Cpp11BracedListStyle: false
 
 # A list of macros that should be interpreted as foreach loops instead of as
 # function calls.
-ForEachMacros: ['for_each_string_list_item']
+ForEachMacros: ['for_each_string_list_item', 'for_each_wanted_builtin', 'for_each_builtin', 'for_each_ut']
 
 # The maximum number of consecutive empty lines to keep.
 MaxEmptyLinesToKeep: 1
diff --git a/Documentation/technical/api-trace2.txt b/Documentation/technical/api-trace2.txt
new file mode 100644 (file)
index 0000000..2de565f
--- /dev/null
@@ -0,0 +1,1349 @@
+= Trace2 API
+
+The Trace2 API can be used to print debug, performance, and telemetry
+information to stderr or a file.  The Trace2 feature is inactive unless
+explicitly enabled by enabling one or more Trace2 Targets.
+
+The Trace2 API is intended to replace the existing (Trace1)
+printf-style tracing provided by the existing `GIT_TRACE` and
+`GIT_TRACE_PERFORMANCE` facilities.  During initial implementation,
+Trace2 and Trace1 may operate in parallel.
+
+The Trace2 API defines a set of high-level messages with known fields,
+such as (`start`: `argv`) and (`exit`: {`exit-code`, `elapsed-time`}).
+
+Trace2 instrumentation throughout the Git code base sends Trace2
+messages to the enabled Trace2 Targets.  Targets transform these
+messages content into purpose-specific formats and write events to
+their data streams.  In this manner, the Trace2 API can drive
+many different types of analysis.
+
+Targets are defined using a VTable allowing easy extension to other
+formats in the future.  This might be used to define a binary format,
+for example.
+
+== Trace2 Targets
+
+Trace2 defines the following set of Trace2 Targets.
+Format details are given in a later section.
+
+`GIT_TR2` (NORMAL)::
+
+       a simple printf format like GIT_TRACE.
++
+------------
+$ export GIT_TR2=~/log.normal
+$ git version
+git version 2.20.1.155.g426c96fcdb
+------------
++
+------------
+$ cat ~/log.normal
+12:28:42.620009 common-main.c:38                  version 2.20.1.155.g426c96fcdb
+12:28:42.620989 common-main.c:39                  start git version
+12:28:42.621101 git.c:432                         cmd_name version (version)
+12:28:42.621215 git.c:662                         exit elapsed:0.001227 code:0
+12:28:42.621250 trace2/tr2_tgt_normal.c:124       atexit elapsed:0.001265 code:0
+------------
+
+`GIT_TR2_PERF` (PERF)::
+
+       a column-based format to replace GIT_TRACE_PERFORMANCE suitable for
+       development and testing, possibly to complement tools like gprof.
++
+------------
+$ export GIT_TR2_PERF=~/log.perf
+$ git version
+git version 2.20.1.155.g426c96fcdb
+------------
++
+------------
+$ cat ~/log.perf
+12:28:42.620675 common-main.c:38                  | d0 | main                     | version      |     |           |           |            | 2.20.1.155.g426c96fcdb
+12:28:42.621001 common-main.c:39                  | d0 | main                     | start        |     |           |           |            | git version
+12:28:42.621111 git.c:432                         | d0 | main                     | cmd_name     |     |           |           |            | version (version)
+12:28:42.621225 git.c:662                         | d0 | main                     | exit         |     |  0.001227 |           |            | code:0
+12:28:42.621259 trace2/tr2_tgt_perf.c:211         | d0 | main                     | atexit       |     |  0.001265 |           |            | code:0
+------------
+
+`GIT_TR2_EVENT` (EVENT)::
+
+       a JSON-based format of event data suitable for telemetry analysis.
++
+------------
+$ export GIT_TR2_EVENT=~/log.event
+$ git version
+git version 2.20.1.155.g426c96fcdb
+------------
++
+------------
+$ cat ~/log.event
+{"event":"version","sid":"1547659722619736-11614","thread":"main","time":"2019-01-16 17:28:42.620713","file":"common-main.c","line":38,"evt":"1","exe":"2.20.1.155.g426c96fcdb"}
+{"event":"start","sid":"1547659722619736-11614","thread":"main","time":"2019-01-16 17:28:42.621027","file":"common-main.c","line":39,"argv":["git","version"]}
+{"event":"cmd_name","sid":"1547659722619736-11614","thread":"main","time":"2019-01-16 17:28:42.621122","file":"git.c","line":432,"name":"version","hierarchy":"version"}
+{"event":"exit","sid":"1547659722619736-11614","thread":"main","time":"2019-01-16 17:28:42.621236","file":"git.c","line":662,"t_abs":0.001227,"code":0}
+{"event":"atexit","sid":"1547659722619736-11614","thread":"main","time":"2019-01-16 17:28:42.621268","file":"trace2/tr2_tgt_event.c","line":163,"t_abs":0.001265,"code":0}
+------------
+
+== Enabling a Target
+
+A Trace2 Target is enabled when the corresponding environment variable
+(`GIT_TR2`, `GIT_TR2_PERF`, or `GIT_TR2_EVENT`) is set.  The following
+values are recognized.
+
+`0`::
+`false`::
+
+       Disables the target.
+
+`1`::
+`true`::
+
+       Enables the target and writes stream to `STDERR`.
+
+`[2-9]`::
+
+       Enables the target and writes to the already opened file descriptor.
+
+`<absolute-pathname>`::
+
+       Enables the target, opens and writes to the file in append mode.
+
+`af_unix:[<socket_type>:]<absolute-pathname>`::
+
+       Enables the target, opens and writes to a Unix Domain Socket
+       (on platforms that support them).
++
+Socket type can be either `stream` or `dgram`.  If the socket type is
+omitted, Git will try both.
+
+== Trace2 API
+
+All public Trace2 functions and macros are defined in `trace2.h` and
+`trace2.c`.  All public symbols are prefixed with `trace2_`.
+
+There are no public Trace2 data structures.
+
+The Trace2 code also defines a set of private functions and data types
+in the `trace2/` directory.  These symbols are prefixed with `tr2_`
+and should only be used by functions in `trace2.c`.
+
+== Conventions for Public Functions and Macros
+
+The functions defined by the Trace2 API are declared and documented
+in `trace2.h`.  It defines the API functions and wrapper macros for
+Trace2.
+
+Some functions have a `_fl()` suffix to indicate that they take `file`
+and `line-number` arguments.
+
+Some functions have a `_va_fl()` suffix to indicate that they also
+take a `va_list` argument.
+
+Some functions have a `_printf_fl()` suffix to indicate that they also
+take a varargs argument.
+
+There are CPP wrapper macros and ifdefs to hide most of these details.
+See `trace2.h` for more details.  The following discussion will only
+describe the simplified forms.
+
+== Public API
+
+All Trace2 API functions send a messsage to all of the active
+Trace2 Targets.  This section describes the set of available
+messages.
+
+It helps to divide these functions into groups for discussion
+purposes.
+
+=== Basic Command Messages
+
+These are concerned with the lifetime of the overall git process.
+
+`void trace2_initialize()`::
+
+       Determines if any Trace2 Targets should be enabled and
+       initializes the Trace2 facility.  This includes starting the
+       elapsed time clocks and thread local storage (TLS).
++
+This function emits a "version" message containing the version of git
+and the Trace2 protocol.
++
+This function should be called from `main()` as early as possible in
+the life of the process.
+
+`int trace2_is_enabled()`::
+
+       Returns 1 if Trace2 is enabled (at least one target is
+       active).
+
+`void trace2_cmd_start(int argc, const char **argv)`::
+
+       Emits a "start" message containing the process command line
+       arguments.
+
+`int trace2_cmd_exit(int exit_code)`::
+
+       Emits an "exit" message containing the process exit-code and
+       elapsed time.
++
+Returns the exit-code.
+
+`void trace2_cmd_error(const char *fmt, va_list ap)`::
+
+       Emits an "error" message containing a formatted error message.
+
+`void trace2_cmd_path(const char *pathname)`::
+
+       Emits a "cmd_path" message with the full pathname of the
+       current process.
+
+=== Command Detail Messages
+
+These are concerned with describing the specific Git command
+after the command line, config, and environment are inspected.
+
+`void trace2_cmd_name(const char *name)`::
+
+       Emits a "cmd_name" message with the canonical name of the
+       command, for example "status" or "checkout".
+
+`void trace2_cmd_mode(const char *mode)`::
+
+       Emits a "cmd_mode" message with a qualifier name to further
+       describe the current git command.
++
+This message is intended to be used with git commands having multiple
+major modes.  For example, a "checkout" command can checkout a new
+branch or it can checkout a single file, so the checkout code could
+emit a cmd_mode message of "branch" or "file".
+
+`void trace2_cmd_alias(const char *alias, const char **argv_expansion)`::
+
+       Emits an "alias" message containing the alias used and the
+       argument expansion.
+
+`void trace2_def_param(const char *parameter, const char *value)`::
+
+       Emits a "def_param" message containing a key/value pair.
++
+This message is intended to report some global aspect of the current
+command, such as a configuration setting or command line switch that
+significantly affects program performance or behavior, such as
+`core.abbrev`, `status.showUntrackedFiles`, or `--no-ahead-behind`.
+
+`void trace2_cmd_list_config()`::
+
+       Emits a "def_param" messages for "important" configuration
+       settings.
++
+The environment variable `GIT_TR2_CONFIG_PARAMS` can be set to a
+list of patterns of important configuration settings, for example:
+`core.*,remote.*.url`.  This function will iterate over all config
+settings and emit a "def_param" message for each match.
+
+`void trace2_cmd_set_config(const char *key, const char *value)`::
+
+       Emits a "def_param" message for a specific configuration
+       setting IFF it matches the `GIT_TR2_CONFIG_PARAMS` pattern.
++
+This is used to hook into `git_config_set()` and catch any
+configuration changes and update a value previously reported by
+`trace2_cmd_list_config()`.
+
+`void trace2_def_repo(struct repository *repo)`::
+
+       Registers a repository with the Trace2 layer.  Assigns a
+       unique "repo-id" to `repo->trace2_repo_id`.
++
+Emits a "worktree" messages containing the repo-id and the worktree
+pathname.
++
+Region and data messages (described later) may refer to this repo-id.
++
+The main/top-level repository will have repo-id value 1 (aka "r1").
++
+The repo-id field is in anticipation of future in-proc submodule
+repositories.
+
+=== Child Process Messages
+
+These are concerned with the various spawned child processes,
+including shell scripts, git commands, editors, pagers, and hooks.
+
+`void trace2_child_start(struct child_process *cmd)`::
+
+       Emits a "child_start" message containing the "child-id",
+       "child-argv", and "child-classification".
++
+Before calling this, set `cmd->trace2_child_class` to a name
+describing the type of child process, for example "editor".
++
+This function assigns a unique "child-id" to `cmd->trace2_child_id`.
+This field is used later during the "child_exit" message to associate
+it with the "child_start" message.
++
+This function should be called before spawning the child process.
+
+`void trace2_child_exit(struct child_proess *cmd, int child_exit_code)`::
+
+       Emits a "child_exit" message containing the "child-id",
+       the child's elapsed time and exit-code.
++
+The reported elapsed time includes the process creation overhead and
+time spend waiting for it to exit, so it may be slightly longer than
+the time reported by the child itself.
++
+This function should be called after reaping the child process.
+
+`int trace2_exec(const char *exe, const char **argv)`::
+
+       Emits a "exec" message containing the "exec-id" and the
+       argv of the new process.
++
+This function should be called before calling one of the `exec()`
+variants, such as `execvp()`.
++
+This function returns a unique "exec-id".  This value is used later
+if the exec() fails and a "exec-result" message is necessary.
+
+`void trace2_exec_result(int exec_id, int error_code)`::
+
+       Emits a "exec_result" message containing the "exec-id"
+       and the error code.
++
+On Unix-based systems, `exec()` does not return if successful.
+This message is used to indicate that the `exec()` failed and
+that the current program is continuing.
+
+=== Git Thread Messages
+
+These messages are concerned with Git thread usage.
+
+`void trace2_thread_start(const char *thread_name)`::
+
+       Emits a "thread_start" message.
++
+The `thread_name` field should be a descriptive name, such as the
+unique name of the thread-proc.  A unique "thread-id" will be added
+to the name to uniquely identify thread instances.
++
+Region and data messages (described later) may refer to this thread
+name.
++
+This function must be called by the thread-proc of the new thread
+(so that TLS data is properly initialized) and not by the caller
+of `pthread_create()`.
+
+`void trace2_thread_exit()`::
+
+       Emits a "thread_exit" message containing the thread name
+       and the thread elapsed time.
++
+This function must be called by the thread-proc before it returns
+(so that the coorect TLS data is used and cleaned up.  It should
+not be called by the caller of `pthread_join()`.
+
+=== Region and Data Messages
+
+These are concerned with recording performance data
+over regions or spans of code.
+
+`void trace2_region_enter(const char *category, const char *label, const struct repository *repo)`::
+
+`void trace2_region_enter_printf(const char *category, const char *label, const struct repository *repo, const char *fmt, ...)`::
+
+`void trace2_region_enter_printf_va(const char *category, const char *label, const struct repository *repo, const char *fmt, va_list ap)`::
+
+       Emits a thread-relative "region_enter" message with optional
+       printf string.
++
+This function pushes a new region nesting stack level on the current
+thread and starts a clock for the new stack frame.
++
+The `category` field is an arbitrary category name used to classify
+regions by feature area, such as "status" or "index".  At this time
+it is only just printed along with the rest of the message.  It may
+be used in the future to filter messages.
++
+The `label` field is an arbitrary label used to describe the activity
+being started, such as "read_recursive" or "do_read_index".
++
+The `repo` field, if set, will be used to get the "repo-id", so that
+recursive oerations can be attributed to the correct repository.
+
+`void trace2_region_leave(const char *category, const char *label, const struct repository *repo)`::
+
+`void trace2_region_leave_printf(const char *category, const char *label, const struct repository *repo, const char *fmt, ...)`::
+
+`void trace2_region_leave_printf_va(const char *category, const char *label, const struct repository *repo, const char *fmt, va_list ap)`::
+
+       Emits a thread-relative "region_leave" message with optional
+       printf string.
++
+This function pops the region nesting stack on the current thread
+and reports the elapsed time of the stack frame.
++
+The `category`, `label`, and `repo` fields are the same as above.
+The `category` and `label` do not need to match the correpsonding
+"region_enter" message, but it makes the data stream easier to
+understand.
+
+`void trace2_data_string(const char *category, const struct repository *repo, const char *key, const char * value)`::
+
+`void trace2_data_intmax(const char *category, const struct repository *repo, const char *key, intmax value)`::
+
+`void trace2_data_json(const char *category, const struct repository *repo, const char *key, const struct json_writer *jw)`::
+
+       Emits a region- and thread-relative "data" or "data_json" message.
++
+This is a key/value pair message containing information about the
+current thread, region stack, and repository.  This could be used
+to print the number of files in a directory during a multi-threaded
+recursive tree walk.
+
+`void trace2_printf(const char *fmt, ...)`::
+
+`void trace2_printf_va(const char *fmt, va_list ap)`::
+
+       Emits a region- and thread-relative "printf" message.
+
+== Trace2 Target Formats
+
+=== NORMAL Format
+
+NORMAL format is enabled when the `GIT_TR2` environment variable is
+set.
+
+Events are written as lines of the form:
+
+------------
+[<time> SP <filename>:<line> SP+] <event-name> [[SP] <event-message>] LF
+------------
+
+`<event-name>`::
+
+       is the event name.
+
+`<event-message>`::
+       is a free-form printf message intended for human consumption.
++
+Note that this may contain embedded LF or CRLF characters that are
+not escaped, so the event may spill across multiple lines.
+
+If `GIT_TR2_BRIEF` is true, the `time`, `filename`, and `line` fields
+are omitted.
+
+This target is intended to be more of a summary (like GIT_TRACE) and
+less detailed than the other targets.  It ignores thread, region, and
+data messages, for example.
+
+=== PERF Format
+
+PERF format is enabled when the `GIT_TR2_PERF` environment variable
+is set.
+
+Events are written as lines of the form:
+
+------------
+[<time> SP <filename>:<line> SP+
+    BAR SP] d<depth> SP
+    BAR SP <thread-name> SP+
+    BAR SP <event-name> SP+
+    BAR SP [r<repo-id>] SP+
+    BAR SP [<t_abs>] SP+
+    BAR SP [<t_rel>] SP+
+    BAR SP [<category>] SP+
+    BAR SP DOTS* <perf-event-message>
+    LF
+------------
+
+`<depth>`::
+       is the git process depth.  This is the number of parent
+       git processes.  A top-level git command has depth value "d0".
+       A child of it has depth value "d1".  A second level child
+       has depth value "d2" and so on.
+
+`<thread-name>`::
+       is a unique name for the thread.  The primary thread
+       is called "main".  Other thread names are of the form "th%d:%s"
+       and include a unique number and the name of the thread-proc.
+
+`<event-name>`::
+       is the event name.
+
+`<repo-id>`::
+       when present, is a number indicating the repository
+       in use.  A `def_repo` event is emitted when a repository is
+       opened.  This defines the repo-id and associated worktree.
+       Subsequent repo-specific events will reference this repo-id.
++
+Currently, this is always "r1" for the main repository.
+This field is in anticipation of in-proc submodules in the future.
+
+`<t_abs>`::
+       when present, is the absolute time in seconds since the
+       program started.
+
+`<t_rel>`::
+       when present, is time in seconds relative to the start of
+       the current region.  For a thread-exit event, it is the elapsed
+       time of the thread.
+
+`<category>`::
+       is present on region and data events and is used to
+       indicate a broad category, such as "index" or "status".
+
+`<perf-event-message>`::
+       is a free-form printf message intended for human consumption.
+
+------------
+15:33:33.532712 wt-status.c:2310                  | d0 | main                     | region_enter | r1  |  0.126064 |           | status     | label:print
+15:33:33.532712 wt-status.c:2331                  | d0 | main                     | region_leave | r1  |  0.127568 |  0.001504 | status     | label:print
+------------
+
+If `GIT_TR2_PERF_BRIEF` is true, the `time`, `file`, and `line`
+fields are omitted.
+
+------------
+d0 | main                     | region_leave | r1  |  0.011717 |  0.009122 | index      | label:preload
+------------
+
+The PERF target is intended for interactive performance analysis
+during development and is quite noisy.
+
+=== EVENT Format
+
+EVENT format is enabled when the `GIT_TR2_EVENT` environment
+variable is set.
+
+Each event is a JSON-object containing multiple key/value pairs
+written as a single line and followed by a LF.
+
+------------
+'{' <key> ':' <value> [',' <key> ':' <value>]* '}' LF
+------------
+
+Some key/value pairs are common to all events and some are
+event-specific.
+
+==== Common Key/Value Pairs
+
+The following key/value pairs are common to all events:
+
+------------
+{
+       "event":"version",
+       "sid":"1547659722619736-11614",
+       "thread":"main",
+       "time":"2019-01-16 17:28:42.620713",
+       "file":"common-main.c",
+       "line":38,
+       ...
+}
+------------
+
+`"event":<event>`::
+       is the event name.
+
+`"sid":<sid>`::
+       is the session-id.  This is a unique string to identify the
+       process instance to allow all events emitted by a process to
+       be identified.  A session-id is used instead of a PID because
+       PIDs are recycled by the OS.  For child git processes, the
+       session-id is prepended with the session-id of the parent git
+       process to allow parent-child relationships to be identified
+       during post-processing.
+
+`"thread":<thread>`::
+       is the thread name.
+
+`"time":<time>`::
+       is the UTC time of the event.
+
+`"file":<filename>`::
+       is source file generating the event.
+
+`"line":<line-number>`::
+       is the integer source line number generating the event.
+
+`"repo":<repo-id>`::
+       when present, is the integer repo-id as described previously.
+
+If `GIT_TR2_EVENT_BRIEF` is true, the `file` and `line` fields are omitted
+from all events and the `time` field is only present on the "start" and
+"atexit" events.
+
+==== Event-Specific Key/Value Pairs
+
+`"version"`::
+       This event gives the version of the executable and the EVENT format.
++
+------------
+{
+       "event":"version",
+       ...
+       "evt":"1",                     # EVENT format version
+       "exe":"2.20.1.155.g426c96fcdb" # git version
+}
+------------
+
+`"start"`::
+       This event contains the complete argv received by main().
++
+------------
+{
+       "event":"start",
+       ...
+       "argv":["git","version"]
+}
+------------
+
+`"exit"`::
+       This event is emitted when git calls `exit()`.
++
+------------
+{
+       "event":"exit",
+       ...
+       "t_abs":0.001227, # elapsed time in seconds
+       "code":0          # exit code
+}
+------------
+
+`"atexit"`::
+       This event is emitted by the Trace2 `atexit` routine during
+       final shutdown.  It should be the last event emitted by the
+       process.
++
+(The elapsed time reported here is greater than the time reported in
+the "exit" event because it runs after all other atexit tasks have
+completed.)
++
+------------
+{
+       "event":"atexit",
+       ...
+       "t_abs":0.001227, # elapsed time in seconds
+       "code":0          # exit code
+}
+------------
+
+`"signal"`::
+       This event is emitted when the program is terminated by a user
+       signal.  Depending on the platform, the signal event may
+       prevent the "atexit" event from being generated.
++
+------------
+{
+       "event":"signal",
+       ...
+       "t_abs":0.001227,  # elapsed time in seconds
+       "signal":13        # SIGTERM, SIGINT, etc.
+}
+------------
+
+`"error"`::
+       This event is emitted when one of the `error()`, `die()`,
+       or `usage()` functions are called.
++
+------------
+{
+       "event":"error",
+       ...
+       "msg":"invalid option: --cahced", # formatted error message
+       "fmt":"invalid option: %s"        # error format string
+}
+------------
++
+The error event may be emitted more than once.  The format string
+allows post-processors to group errors by type without worrying
+about specific error arguments.
+
+`"cmd_path"`::
+       This event contains the discovered full path of the git
+       executable (on platforms that are configured to resolve it).
++
+------------
+{
+       "event":"cmd_path",
+       ...
+       "path":"C:/work/gfw/git.exe"
+}
+------------
+
+`"cmd_name"`::
+       This event contains the command name for this git process
+       and the hierarchy of commands from parent git processes.
++
+------------
+{
+       "event":"cmd_name",
+       ...
+       "name":"pack-objects",
+       "hierarchy":"push/pack-objects"
+}
+------------
++
+Normally, the "name" field contains the canonical name of the
+command.  When a canonical name is not available, one of
+these special values are used:
++
+------------
+"_query_"            # "git --html-path"
+"_run_dashed_"       # when "git foo" tries to run "git-foo"
+"_run_shell_alias_"  # alias expansion to a shell command
+"_run_git_alias_"    # alias expansion to a git command
+"_usage_"            # usage error
+------------
+
+`"cmd_mode"`::
+       This event, when present, describes the command variant This
+       event may be emitted more than once.
++
+------------
+{
+       "event":"cmd_mode",
+       ...
+       "name":"branch"
+}
+------------
++
+The "name" field is an arbitrary string to describe the command mode.
+For example, checkout can checkout a branch or an individual file.
+And these variations typically have different performance
+characteristics that are not comparable.
+
+`"alias"`::
+       This event is present when an alias is expanded.
++
+------------
+{
+       "event":"alias",
+       ...
+       "alias":"l",             # registered alias
+       "argv":["log","--graph"] # alias expansion
+}
+------------
+
+`"child_start"`::
+       This event describes a child process that is about to be
+       spawned.
++
+------------
+{
+       "event":"child_start",
+       ...
+       "child_id":2,
+       "child_class":"?",
+       "use_shell":false,
+       "argv":["git","rev-list","--objects","--stdin","--not","--all","--quiet"]
+
+       "hook_name":"<hook_name>"  # present when child_class is "hook"
+       "cd":"<path>"              # present when cd is required
+}
+------------
++
+The "child_id" field can be used to match this child_start with the
+corresponding child_exit event.
++
+The "child_class" field is a rough classification, such as "editor",
+"pager", "transport/*", and "hook".  Unclassified children are classified
+with "?".
+
+`"child_exit"`::
+       This event is generated after the current process has returned
+       from the waitpid() and collected the exit information from the
+       child.
++
+------------
+{
+       "event":"child_exit",
+       ...
+       "child_id":2,
+       "pid":14708,     # child PID
+       "code":0,        # child exit-code
+       "t_rel":0.110605 # observed run-time of child process
+}
+------------
++
+Note that the session-id of the child process is not available to
+the current/spawning process, so the child's PID is reported here as
+a hint for post-processing.  (But it is only a hint because the child
+proces may be a shell script which doesn't have a session-id.)
++
+Note that the `t_rel` field contains the observed run time in seconds
+for the child process (starting before the fork/exec/spawn and
+stopping after the waitpid() and includes OS process creation overhead).
+So this time will be slightly larger than the atexit time reported by
+the child process itself.
+
+`"exec"`::
+       This event is generated before git attempts to `exec()`
+       another command rather than starting a child process.
++
+------------
+{
+       "event":"exec",
+       ...
+       "exec_id":0,
+       "exe":"git",
+       "argv":["foo", "bar"]
+}
+------------
++
+The "exec_id" field is a command-unique id and is only useful if the
+`exec()` fails and a corresponding exec_result event is generated.
+
+`"exec_result"`::
+       This event is generated if the `exec()` fails and control
+       returns to the current git command.
++
+------------
+{
+       "event":"exec_result",
+       ...
+       "exec_id":0,
+       "code":1      # error code (errno) from exec()
+}
+------------
+
+`"thread_start"`::
+       This event is generated when a thread is started.  It is
+       generated from *within* the new thread's thread-proc (for TLS
+       reasons).
++
+------------
+{
+       "event":"thread_start",
+       ...
+       "thread":"th02:preload_thread" # thread name
+}
+------------
+
+`"thread_exit"`::
+       This event is generated when a thread exits.  It is generated
+       from *within* the thread's thread-proc (for TLS reasons).
++
+------------
+{
+       "event":"thread_exit",
+       ...
+       "thread":"th02:preload_thread", # thread name
+       "t_rel":0.007328                # thread elapsed time
+}
+------------
+
+`"def_param"`::
+       This event is generated to log a global parameter.
++
+------------
+{
+       "event":"def_param",
+       ...
+       "param":"core.abbrev",
+       "value":"7"
+}
+------------
+
+`"def_repo"`::
+       This event defines a repo-id and associates it with the root
+       of the worktree.
++
+------------
+{
+       "event":"def_repo",
+       ...
+       "repo":1,
+       "worktree":"/Users/jeffhost/work/gfw"
+}
+------------
++
+As stated earlier, the repo-id is currently always 1, so there will
+only be one def_repo event.  Later, if in-proc submodules are
+supported, a def_repo event should be emitted for each submodule
+visited.
+
+`"region_enter"`::
+       This event is generated when entering a region.
++
+------------
+{
+       "event":"region_enter",
+       ...
+       "repo":1,                # optional
+       "nesting":1,             # current region stack depth
+       "category":"index",      # optional
+       "label":"do_read_index", # optional
+       "msg":".git/index"       # optional
+}
+------------
++
+The `category` field may be used in a future enhancement to
+do category-based filtering.
++
+The `GIT_TR2_EVENT_NESTING` environment variable can be used to
+filter deeply nested regions and data events.  It defaults to "2".
+
+`"region_leave"`::
+       This event is generated when leaving a region.
++
+------------
+{
+       "event":"region_leave",
+       ...
+       "repo":1,                # optional
+       "t_rel":0.002876,        # time spent in region in seconds
+       "nesting":1,             # region stack depth
+       "category":"index",      # optional
+       "label":"do_read_index", # optional
+       "msg":".git/index"       # optional
+}
+------------
+
+`"data"`::
+       This event is generated to log a thread- and region-local
+       key/value pair.
++
+------------
+{
+       "event":"data",
+       ...
+       "repo":1,              # optional
+       "t_abs":0.024107,      # absolute elapsed time
+       "t_rel":0.001031,      # elapsed time in region/thread
+       "nesting":2,           # region stack depth
+       "category":"index",
+       "key":"read/cache_nr",
+       "value":"3552"
+}
+------------
++
+The "value" field may be an integer or a string.
+
+`"data-json"`::
+       This event is generated to log a pre-formatted JSON string
+       containing structured data.
++
+------------
+{
+       "event":"data_json",
+       ...
+       "repo":1,              # optional
+       "t_abs":0.015905,
+       "t_rel":0.015905,
+       "nesting":1,
+       "category":"process",
+       "key":"windows/ancestry",
+       "value":["bash.exe","bash.exe"]
+}
+------------
+
+== Example Trace2 API Usage
+
+Here is a hypothetical usage of the Trace2 API showing the intended
+usage (without worrying about the actual Git details).
+
+Initialization::
+
+       Initialization happens in `main()`.  Behind the scenes, an
+       `atexit` and `signal` handler are registered.
++
+----------------
+int main(int argc, const char **argv)
+{
+       int exit_code;
+
+       trace2_initialize();
+       trace2_cmd_start(argv);
+
+       exit_code = cmd_main(argc, argv);
+
+       trace2_cmd_exit(exit_code);
+
+       return exit_code;
+}
+----------------
+
+Command Details::
+
+       After the basics are established, additional command
+       information can be sent to Trace2 as it is discovered.
++
+----------------
+int cmd_checkout(int argc, const char **argv)
+{
+       trace2_cmd_name("checkout");
+       trace2_cmd_mode("branch");
+       trace2_def_repo(the_repository);
+
+       // emit "def_param" messages for "interesting" config settings.
+       trace2_cmd_list_config();
+
+       if (do_something())
+           trace2_cmd_error("Path '%s': cannot do something", path);
+
+       return 0;
+}
+----------------
+
+Child Processes::
+
+       Wrap code spawning child processes.
++
+----------------
+void run_child(...)
+{
+       int child_exit_code;
+       struct child_process cmd = CHILD_PROCESS_INIT;
+       ...
+       cmd.trace2_child_class = "editor";
+
+       trace2_child_start(&cmd);
+       child_exit_code = spawn_child_and_wait_for_it();
+       trace2_child_exit(&cmd, child_exit_code);
+}
+----------------
++
+For example, the following fetch command spawned ssh, index-pack,
+rev-list, and gc.  This example also shows that fetch took
+5.199 seconds and of that 4.932 was in ssh.
++
+----------------
+$ export GIT_TR2_BRIEF=1
+$ export GIT_TR2=~/log.normal
+$ git fetch origin
+...
+----------------
++
+----------------
+$ cat ~/log.normal
+version 2.20.1.vfs.1.1.47.g534dbe1ad1
+start git fetch origin
+worktree /Users/jeffhost/work/gfw
+cmd_name fetch (fetch)
+child_start[0] ssh git@github.com ...
+child_start[1] git index-pack ...
+... (Trace2 events from child processes omitted)
+child_exit[1] pid:14707 code:0 elapsed:0.076353
+child_exit[0] pid:14706 code:0 elapsed:4.931869
+child_start[2] git rev-list ...
+... (Trace2 events from child process omitted)
+child_exit[2] pid:14708 code:0 elapsed:0.110605
+child_start[3] git gc --auto
+... (Trace2 events from child process omitted)
+child_exit[3] pid:14709 code:0 elapsed:0.006240
+exit elapsed:5.198503 code:0
+atexit elapsed:5.198541 code:0
+----------------
++
+When a git process is a (direct or indirect) child of another
+git process, it inherits Trace2 context information.  This
+allows the child to print the command hierarchy.  This example
+shows gc as child[3] of fetch.  When the gc process reports
+its name as "gc", it also reports the hierarchy as "fetch/gc".
+(In this example, trace2 messages from the child process is
+indented for clarity.)
++
+----------------
+$ export GIT_TR2_BRIEF=1
+$ export GIT_TR2=~/log.normal
+$ git fetch origin
+...
+----------------
++
+----------------
+$ cat ~/log.normal
+version 2.20.1.160.g5676107ecd.dirty
+start git fetch official
+worktree /Users/jeffhost/work/gfw
+cmd_name fetch (fetch)
+...
+child_start[3] git gc --auto
+    version 2.20.1.160.g5676107ecd.dirty
+    start /Users/jeffhost/work/gfw/git gc --auto
+    worktree /Users/jeffhost/work/gfw
+    cmd_name gc (fetch/gc)
+    exit elapsed:0.001959 code:0
+    atexit elapsed:0.001997 code:0
+child_exit[3] pid:20303 code:0 elapsed:0.007564
+exit elapsed:3.868938 code:0
+atexit elapsed:3.868970 code:0
+----------------
+
+Regions::
+
+       Regions can be use to time an interesting section of code.
++
+----------------
+void wt_status_collect(struct wt_status *s)
+{
+       trace2_region_enter("status", "worktrees", s->repo);
+       wt_status_collect_changes_worktree(s);
+       trace2_region_leave("status", "worktrees", s->repo);
+
+       trace2_region_enter("status", "index", s->repo);
+       wt_status_collect_changes_index(s);
+       trace2_region_leave("status", "index", s->repo);
+
+       trace2_region_enter("status", "untracked", s->repo);
+       wt_status_collect_untracked(s);
+       trace2_region_leave("status", "untracked", s->repo);
+}
+
+void wt_status_print(struct wt_status *s)
+{
+       trace2_region_enter("status", "print", s->repo);
+       switch (s->status_format) {
+           ...
+       }
+       trace2_region_leave("status", "print", s->repo);
+}
+----------------
++
+In this example, scanning for untracked files ran from +0.012568 to
++0.027149 (since the process started) and took 0.014581 seconds.
++
+----------------
+$ export GIT_TR2_PERF_BRIEF=1
+$ export GIT_TR2_PERF=~/log.perf
+$ git status
+...
+
+$ cat ~/log.perf
+d0 | main                     | version      |     |           |           |            | 2.20.1.160.g5676107ecd.dirty
+d0 | main                     | start        |     |           |           |            | git status
+d0 | main                     | def_repo     | r1  |           |           |            | worktree:/Users/jeffhost/work/gfw
+d0 | main                     | cmd_name     |     |           |           |            | status (status)
+...
+d0 | main                     | region_enter | r1  |  0.010988 |           | status     | label:worktrees
+d0 | main                     | region_leave | r1  |  0.011236 |  0.000248 | status     | label:worktrees
+d0 | main                     | region_enter | r1  |  0.011260 |           | status     | label:index
+d0 | main                     | region_leave | r1  |  0.012542 |  0.001282 | status     | label:index
+d0 | main                     | region_enter | r1  |  0.012568 |           | status     | label:untracked
+d0 | main                     | region_leave | r1  |  0.027149 |  0.014581 | status     | label:untracked
+d0 | main                     | region_enter | r1  |  0.027411 |           | status     | label:print
+d0 | main                     | region_leave | r1  |  0.028741 |  0.001330 | status     | label:print
+d0 | main                     | exit         |     |  0.028778 |           |            | code:0
+d0 | main                     | atexit       |     |  0.028809 |           |            | code:0
+----------------
++
+Regions may be nested.  This causes messages to be indented in the
+PERF target, for example.
+Elapsed times are relative to the start of the correpsonding nesting
+level as expected.  For example, if we add region message to:
++
+----------------
+static enum path_treatment read_directory_recursive(struct dir_struct *dir,
+       struct index_state *istate, const char *base, int baselen,
+       struct untracked_cache_dir *untracked, int check_only,
+       int stop_at_first_file, const struct pathspec *pathspec)
+{
+       enum path_treatment state, subdir_state, dir_state = path_none;
+
+       trace2_region_enter_printf("dir", "read_recursive", NULL, "%.*s", baselen, base);
+       ...
+       trace2_region_leave_printf("dir", "read_recursive", NULL, "%.*s", baselen, base);
+       return dir_state;
+}
+----------------
++
+We can further investigate the time spent scanning for untracked files.
++
+----------------
+$ export GIT_TR2_PERF_BRIEF=1
+$ export GIT_TR2_PERF=~/log.perf
+$ git status
+...
+$ cat ~/log.perf
+d0 | main                     | version      |     |           |           |            | 2.20.1.162.gb4ccea44db.dirty
+d0 | main                     | start        |     |           |           |            | git status
+d0 | main                     | def_repo     | r1  |           |           |            | worktree:/Users/jeffhost/work/gfw
+d0 | main                     | cmd_name     |     |           |           |            | status (status)
+...
+d0 | main                     | region_enter | r1  |  0.015047 |           | status     | label:untracked
+d0 | main                     | region_enter |     |  0.015132 |           | dir        | ..label:read_recursive
+d0 | main                     | region_enter |     |  0.016341 |           | dir        | ....label:read_recursive vcs-svn/
+d0 | main                     | region_leave |     |  0.016422 |  0.000081 | dir        | ....label:read_recursive vcs-svn/
+d0 | main                     | region_enter |     |  0.016446 |           | dir        | ....label:read_recursive xdiff/
+d0 | main                     | region_leave |     |  0.016522 |  0.000076 | dir        | ....label:read_recursive xdiff/
+d0 | main                     | region_enter |     |  0.016612 |           | dir        | ....label:read_recursive git-gui/
+d0 | main                     | region_enter |     |  0.016698 |           | dir        | ......label:read_recursive git-gui/po/
+d0 | main                     | region_enter |     |  0.016810 |           | dir        | ........label:read_recursive git-gui/po/glossary/
+d0 | main                     | region_leave |     |  0.016863 |  0.000053 | dir        | ........label:read_recursive git-gui/po/glossary/
+...
+d0 | main                     | region_enter |     |  0.031876 |           | dir        | ....label:read_recursive builtin/
+d0 | main                     | region_leave |     |  0.032270 |  0.000394 | dir        | ....label:read_recursive builtin/
+d0 | main                     | region_leave |     |  0.032414 |  0.017282 | dir        | ..label:read_recursive
+d0 | main                     | region_leave | r1  |  0.032454 |  0.017407 | status     | label:untracked
+...
+d0 | main                     | exit         |     |  0.034279 |           |            | code:0
+d0 | main                     | atexit       |     |  0.034322 |           |            | code:0
+----------------
++
+Trace2 regions are similar to the existing trace_performance_enter()
+and trace_performance_leave() routines, but are thread safe and
+maintain per-thread stacks of timers.
+
+Data Messages::
+
+       Data messages added to a region.
++
+----------------
+int read_index_from(struct index_state *istate, const char *path,
+       const char *gitdir)
+{
+       trace2_region_enter_printf("index", "do_read_index", the_repository, "%s", path);
+
+       ...
+
+       trace2_data_intmax("index", the_repository, "read/version", istate->version);
+       trace2_data_intmax("index", the_repository, "read/cache_nr", istate->cache_nr);
+
+       trace2_region_leave_printf("index", "do_read_index", the_repository, "%s", path);
+}
+----------------
++
+This example shows that the index contained 3552 entries.
++
+----------------
+$ export GIT_TR2_PERF_BRIEF=1
+$ export GIT_TR2_PERF=~/log.perf
+$ git status
+...
+$ cat ~/log.perf
+d0 | main                     | version      |     |           |           |            | 2.20.1.156.gf9916ae094.dirty
+d0 | main                     | start        |     |           |           |            | git status
+d0 | main                     | def_repo     | r1  |           |           |            | worktree:/Users/jeffhost/work/gfw
+d0 | main                     | cmd_name     |     |           |           |            | status (status)
+d0 | main                     | region_enter | r1  |  0.001791 |           | index      | label:do_read_index .git/index
+d0 | main                     | data         | r1  |  0.002494 |  0.000703 | index      | ..read/version:2
+d0 | main                     | data         | r1  |  0.002520 |  0.000729 | index      | ..read/cache_nr:3552
+d0 | main                     | region_leave | r1  |  0.002539 |  0.000748 | index      | label:do_read_index .git/index
+...
+----------------
+
+Thread Events::
+
+       Thread messages added to a thread-proc.
++
+For example, the multithreaded preload-index code can be
+instrumented with a region around the thread pool and then
+per-thread start and exit events within the threadproc.
++
+----------------
+static void *preload_thread(void *_data)
+{
+       // start the per-thread clock and emit a message.
+       trace2_thread_start("preload_thread");
+
+       // report which chunk of the array this thread was assigned.
+       trace2_data_intmax("index", the_repository, "offset", p->offset);
+       trace2_data_intmax("index", the_repository, "count", nr);
+
+       do {
+           ...
+       } while (--nr > 0);
+       ...
+
+       // report elapsed time taken by this thread.
+       trace2_thread_exit();
+       return NULL;
+}
+
+void preload_index(struct index_state *index,
+       const struct pathspec *pathspec,
+       unsigned int refresh_flags)
+{
+       trace2_region_enter("index", "preload", the_repository);
+
+       for (i = 0; i < threads; i++) {
+           ... /* create thread */
+       }
+
+       for (i = 0; i < threads; i++) {
+           ... /* join thread */
+       }
+
+       trace2_region_leave("index", "preload", the_repository);
+}
+----------------
++
+In this example preload_index() was executed by the `main` thread
+and started the `preload` region.  Seven threads, named
+`th01:preload_thread` through `th07:preload_thread`, were started.
+Events from each thread are atomically appended to the shared target
+stream as they occur so they may appear in random order with respect
+other threads. Finally, the main thread waits for the threads to
+finish and leaves the region.
++
+Data events are tagged with the active thread name.  They are used
+to report the per-thread parameters.
++
+----------------
+$ export GIT_TR2_PERF_BRIEF=1
+$ export GIT_TR2_PERF=~/log.perf
+$ git status
+...
+$ cat ~/log.perf
+...
+d0 | main                     | region_enter | r1  |  0.002595 |           | index      | label:preload
+d0 | th01:preload_thread      | thread_start |     |  0.002699 |           |            |
+d0 | th02:preload_thread      | thread_start |     |  0.002721 |           |            |
+d0 | th01:preload_thread      | data         | r1  |  0.002736 |  0.000037 | index      | offset:0
+d0 | th02:preload_thread      | data         | r1  |  0.002751 |  0.000030 | index      | offset:2032
+d0 | th03:preload_thread      | thread_start |     |  0.002711 |           |            |
+d0 | th06:preload_thread      | thread_start |     |  0.002739 |           |            |
+d0 | th01:preload_thread      | data         | r1  |  0.002766 |  0.000067 | index      | count:508
+d0 | th06:preload_thread      | data         | r1  |  0.002856 |  0.000117 | index      | offset:2540
+d0 | th03:preload_thread      | data         | r1  |  0.002824 |  0.000113 | index      | offset:1016
+d0 | th04:preload_thread      | thread_start |     |  0.002710 |           |            |
+d0 | th02:preload_thread      | data         | r1  |  0.002779 |  0.000058 | index      | count:508
+d0 | th06:preload_thread      | data         | r1  |  0.002966 |  0.000227 | index      | count:508
+d0 | th07:preload_thread      | thread_start |     |  0.002741 |           |            |
+d0 | th07:preload_thread      | data         | r1  |  0.003017 |  0.000276 | index      | offset:3048
+d0 | th05:preload_thread      | thread_start |     |  0.002712 |           |            |
+d0 | th05:preload_thread      | data         | r1  |  0.003067 |  0.000355 | index      | offset:1524
+d0 | th05:preload_thread      | data         | r1  |  0.003090 |  0.000378 | index      | count:508
+d0 | th07:preload_thread      | data         | r1  |  0.003037 |  0.000296 | index      | count:504
+d0 | th03:preload_thread      | data         | r1  |  0.002971 |  0.000260 | index      | count:508
+d0 | th04:preload_thread      | data         | r1  |  0.002983 |  0.000273 | index      | offset:508
+d0 | th04:preload_thread      | data         | r1  |  0.007311 |  0.004601 | index      | count:508
+d0 | th05:preload_thread      | thread_exit  |     |  0.008781 |  0.006069 |            |
+d0 | th01:preload_thread      | thread_exit  |     |  0.009561 |  0.006862 |            |
+d0 | th03:preload_thread      | thread_exit  |     |  0.009742 |  0.007031 |            |
+d0 | th06:preload_thread      | thread_exit  |     |  0.009820 |  0.007081 |            |
+d0 | th02:preload_thread      | thread_exit  |     |  0.010274 |  0.007553 |            |
+d0 | th07:preload_thread      | thread_exit  |     |  0.010477 |  0.007736 |            |
+d0 | th04:preload_thread      | thread_exit  |     |  0.011657 |  0.008947 |            |
+d0 | main                     | region_leave | r1  |  0.011717 |  0.009122 | index      | label:preload
+...
+d0 | main                     | exit         |     |  0.029996 |           |            | code:0
+d0 | main                     | atexit       |     |  0.030027 |           |            | code:0
+----------------
++
+In this example, the preload region took 0.009122 seconds.  The 7 threads
+took between 0.006069 and 0.008947 seconds to work on their portion of
+the index.  Thread "th01" worked on 508 items at offset 0.  Thread "th02"
+worked on 508 items at offset 2032.  Thread "th04" worked on 508 itemts
+at offset 508.
++
+This example also shows that thread names are assigned in a racy manner
+as each thread starts and allocates TLS storage.
+
+== Future Work
+
+=== Relationship to the Existing Trace Api (api-trace.txt)
+
+There are a few issues to resolve before we can completely
+switch to Trace2.
+
+* Updating existing tests that assume GIT_TRACE format messages.
+
+* How to best handle custom GIT_TRACE_<key> messages?
+
+** The GIT_TRACE_<key> mechanism allows each <key> to write to a
+different file (in addition to just stderr).
+
+** Do we want to maintain that ability or simply write to the existing
+Trace2 targets (and convert <key> to a "category").
index c5240942f29e788ac08daa9329de52aaa3415708..148668368bf1708900bf4a62120004747718e8c9 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -773,6 +773,7 @@ TEST_BUILTINS_OBJS += test-string-list.o
 TEST_BUILTINS_OBJS += test-submodule-config.o
 TEST_BUILTINS_OBJS += test-submodule-nested-repo-config.o
 TEST_BUILTINS_OBJS += test-subprocess.o
+TEST_BUILTINS_OBJS += test-trace2.o
 TEST_BUILTINS_OBJS += test-urlmatch-normalization.o
 TEST_BUILTINS_OBJS += test-xml-encode.o
 TEST_BUILTINS_OBJS += test-wildmatch.o
@@ -1017,6 +1018,16 @@ LIB_OBJS += tempfile.o
 LIB_OBJS += thread-utils.o
 LIB_OBJS += tmp-objdir.o
 LIB_OBJS += trace.o
+LIB_OBJS += trace2.o
+LIB_OBJS += trace2/tr2_cfg.o
+LIB_OBJS += trace2/tr2_cmd_name.o
+LIB_OBJS += trace2/tr2_dst.o
+LIB_OBJS += trace2/tr2_sid.o
+LIB_OBJS += trace2/tr2_tbuf.o
+LIB_OBJS += trace2/tr2_tgt_event.o
+LIB_OBJS += trace2/tr2_tgt_normal.o
+LIB_OBJS += trace2/tr2_tgt_perf.o
+LIB_OBJS += trace2/tr2_tls.o
 LIB_OBJS += trailer.o
 LIB_OBJS += transport.o
 LIB_OBJS += transport-helper.o
@@ -1596,7 +1607,9 @@ ifdef NO_INET_PTON
        LIB_OBJS += compat/inet_pton.o
        BASIC_CFLAGS += -DNO_INET_PTON
 endif
-ifndef NO_UNIX_SOCKETS
+ifdef NO_UNIX_SOCKETS
+       BASIC_CFLAGS += -DNO_UNIX_SOCKETS
+else
        LIB_OBJS += unix-socket.o
        PROGRAM_OBJS += credential-cache.o
        PROGRAM_OBJS += credential-cache--daemon.o
index cd051fecdfc8e178496a698d9c7e7df5a6dd894e..86e33495b039bd44d4b59625388d55cd624ccd26 100644 (file)
@@ -453,6 +453,7 @@ static int run_post_rewrite_hook(const struct am_state *state)
 
        cp.in = xopen(am_path(state, "rewritten"), O_RDONLY);
        cp.stdout_to_stderr = 1;
+       cp.trace2_hook_name = "post-rewrite";
 
        ret = run_command(&cp);
 
index bea08ef959189cff99e34170a2999a52953a3020..0e6037b2968f326ca2781fa141d74683e52c983c 100644 (file)
@@ -325,6 +325,8 @@ static int checkout_paths(const struct checkout_opts *opts,
        struct lock_file lock_file = LOCK_INIT;
        int nr_checkouts = 0, nr_unmerged = 0;
 
+       trace2_cmd_mode(opts->patch_mode ? "patch" : "path");
+
        if (opts->track != BRANCH_TRACK_UNSPECIFIED)
                die(_("'%s' cannot be used with updating paths"), "--track");
 
@@ -1014,6 +1016,9 @@ static int switch_branches(const struct checkout_opts *opts,
        void *path_to_free;
        struct object_id rev;
        int flag, writeout_error = 0;
+
+       trace2_cmd_mode("branch");
+
        memset(&old_branch_info, 0, sizeof(old_branch_info));
        old_branch_info.path = path_to_free = resolve_refdup("HEAD", 0, &rev, &flag);
        if (old_branch_info.path)
@@ -1251,6 +1256,8 @@ static int switch_unborn_to_new_branch(const struct checkout_opts *opts)
        int status;
        struct strbuf branch_ref = STRBUF_INIT;
 
+       trace2_cmd_mode("unborn");
+
        if (!opts->new_branch)
                die(_("You are on a branch yet to be born"));
        strbuf_addf(&branch_ref, "refs/heads/%s", opts->new_branch);
index a9fac7c128c1eb45026965a79db1387a8bdb92de..a154fc29f6b7841c2417ca302b631437e7376baa 100644 (file)
@@ -33,6 +33,7 @@
 #include "object-store.h"
 #include "dir.h"
 #include "midx.h"
+#include "trace2.h"
 
 #define IN_PACK(obj) oe_in_pack(&to_pack, obj)
 #define SIZE(obj) oe_size(&to_pack, obj)
@@ -3473,6 +3474,8 @@ int cmd_pack_objects(int argc, const char **argv, const char *prefix)
                }
        }
 
+       trace2_region_enter("pack-objects", "enumerate-objects",
+                           the_repository);
        prepare_packing_data(the_repository, &to_pack);
 
        if (progress)
@@ -3487,12 +3490,23 @@ int cmd_pack_objects(int argc, const char **argv, const char *prefix)
        if (include_tag && nr_result)
                for_each_ref(add_ref_tag, NULL);
        stop_progress(&progress_state);
+       trace2_region_leave("pack-objects", "enumerate-objects",
+                           the_repository);
 
        if (non_empty && !nr_result)
                return 0;
-       if (nr_result)
+       if (nr_result) {
+               trace2_region_enter("pack-objects", "prepare-pack",
+                                   the_repository);
                prepare_pack(window, depth);
+               trace2_region_leave("pack-objects", "prepare-pack",
+                                   the_repository);
+       }
+
+       trace2_region_enter("pack-objects", "write-pack-file", the_repository);
        write_pack_file();
+       trace2_region_leave("pack-objects", "write-pack-file", the_repository);
+
        if (progress)
                fprintf_ln(stderr,
                           _("Total %"PRIu32" (delta %"PRIu32"),"
index 7c7bc13e912aa8ba5d2c4dfa781fb74cd20ac6d4..52114cbf0d9f98d52a5b48d8806019d14b1c7029 100644 (file)
@@ -1027,6 +1027,14 @@ int cmd_rebase(int argc, const char **argv, const char *prefix)
                ACTION_EDIT_TODO,
                ACTION_SHOW_CURRENT_PATCH,
        } action = NO_ACTION;
+       static const char *action_names[] = { N_("undefined"),
+                                             N_("continue"),
+                                             N_("skip"),
+                                             N_("abort"),
+                                             N_("quit"),
+                                             N_("edit_todo"),
+                                             N_("show_current_patch"),
+                                             NULL };
        const char *gpg_sign = NULL;
        struct string_list exec = STRING_LIST_INIT_NODUP;
        const char *rebase_merges = NULL;
@@ -1212,6 +1220,15 @@ int cmd_rebase(int argc, const char **argv, const char *prefix)
                die(_("The --edit-todo action can only be used during "
                      "interactive rebase."));
 
+       if (trace2_is_enabled()) {
+               if (is_interactive(&options))
+                       trace2_cmd_mode("interactive");
+               else if (exec.nr)
+                       trace2_cmd_mode("interactive-exec");
+               else
+                       trace2_cmd_mode(action_names[action]);
+       }
+
        switch (action) {
        case ACTION_CONTINUE: {
                struct object_id head;
index d58b7750b6b46565ca4ebb8299e5260943aa364e..8bc714a5fc30e13cff98dc7ff7e68578b4842863 100644 (file)
@@ -694,6 +694,8 @@ static int run_and_feed_hook(const char *hook_name, feed_fn feed,
        proc.argv = argv;
        proc.in = -1;
        proc.stdout_to_stderr = 1;
+       proc.trace2_hook_name = hook_name;
+
        if (feed_state->push_options) {
                int i;
                for (i = 0; i < feed_state->push_options->nr; i++)
@@ -807,6 +809,7 @@ static int run_update_hook(struct command *cmd)
        proc.stdout_to_stderr = 1;
        proc.err = use_sideband ? -1 : 0;
        proc.argv = argv;
+       proc.trace2_hook_name = "update";
 
        code = start_command(&proc);
        if (code)
@@ -1190,6 +1193,7 @@ static void run_update_post_hook(struct command *commands)
        proc.no_stdin = 1;
        proc.stdout_to_stderr = 1;
        proc.err = use_sideband ? -1 : 0;
+       proc.trace2_hook_name = "post-update";
 
        if (!start_command(&proc)) {
                if (use_sideband)
index 4d18a461fab631dd752adec3b95197a3a2657a62..7882829a95d8294ea5bb5bcba3335e651233d79a 100644 (file)
@@ -341,6 +341,7 @@ int cmd_reset(int argc, const char **argv, const char *prefix)
        if (patch_mode) {
                if (reset_type != NONE)
                        die(_("--patch is incompatible with --{hard,mixed,soft}"));
+               trace2_cmd_mode("patch-interactive");
                return run_add_interactive(rev, "--patch=reset", &pathspec);
        }
 
@@ -357,6 +358,11 @@ int cmd_reset(int argc, const char **argv, const char *prefix)
        if (reset_type == NONE)
                reset_type = MIXED; /* by default */
 
+       if (pathspec.nr)
+               trace2_cmd_mode("path");
+       else
+               trace2_cmd_mode(reset_type_names[reset_type]);
+
        if (reset_type != SOFT && (reset_type != MIXED || get_git_work_tree()))
                setup_work_tree();
 
index b80fc4ba3d88b56436fa3f6b9a132bfe9e82b79b..6bcc4f1bd773b38f5895d3404419e362ded63d2a 100644 (file)
@@ -1816,11 +1816,10 @@ static int update_submodules(struct submodule_update_clone *suc)
 {
        int i;
 
-       run_processes_parallel(suc->max_jobs,
-                              update_clone_get_next_task,
-                              update_clone_start_failure,
-                              update_clone_task_finished,
-                              suc);
+       run_processes_parallel_tr2(suc->max_jobs, update_clone_get_next_task,
+                                  update_clone_start_failure,
+                                  update_clone_task_finished, suc, "submodule",
+                                  "parallel/update");
 
        /*
         * We saved the output and put it out all at once now.
index 3f9907fcc994d248ba604509f6feb5bdc0499329..6cc094a453806308442d054a7d1c073ecf18b87b 100644 (file)
@@ -402,6 +402,7 @@ static int add_worktree(const char *path, const char *refname,
                        cp.dir = path;
                        cp.env = env;
                        cp.argv = NULL;
+                       cp.trace2_hook_name = "post-checkout";
                        argv_array_pushl(&cp.args, absolute_path(hook),
                                         oid_to_hex(&null_oid),
                                         oid_to_hex(&commit->object.oid),
diff --git a/cache.h b/cache.h
index bff556e7720b2aec7c2824b7101a0c5bd175551b..abd518a9a23394fd47b572c6957c712abac139a2 100644 (file)
--- a/cache.h
+++ b/cache.h
@@ -9,6 +9,7 @@
 #include "gettext.h"
 #include "convert.h"
 #include "trace.h"
+#include "trace2.h"
 #include "string-list.h"
 #include "pack-revindex.h"
 #include "hash.h"
index 3728f66b4cce80d298aab0e551a2d3c03e2c4357..d484aec20979ac9a1ea6d49b166f51436a24dfad 100644 (file)
@@ -25,12 +25,19 @@ static void restore_sigpipe_to_default(void)
 
 int main(int argc, const char **argv)
 {
+       int result;
+
        /*
         * Always open file descriptors 0/1/2 to avoid clobbering files
         * in die().  It also avoids messing up when the pipes are dup'ed
         * onto stdin/stdout/stderr in the child processes we spawn.
         */
        sanitize_stdfds();
+       restore_sigpipe_to_default();
+
+       trace2_initialize();
+       trace2_cmd_start(argv);
+       trace2_collect_process_info();
 
        git_resolve_executable_dir(argv[0]);
 
@@ -40,7 +47,9 @@ int main(int argc, const char **argv)
 
        attr_start();
 
-       restore_sigpipe_to_default();
+       result = cmd_main(argc, argv);
+
+       trace2_cmd_exit(result);
 
-       return cmd_main(argc, argv);
+       return result;
 }
index 8141f77189c66b07a1e1cd5ab92418d0de4617e5..6b04514cdc62167da027b48bae816e72811f1584 100644 (file)
@@ -1551,19 +1551,23 @@ static int try_shell_exec(const char *cmd, char *const *argv)
                return 0;
        prog = path_lookup(interpr, 1);
        if (prog) {
+               int exec_id;
                int argc = 0;
                const char **argv2;
                while (argv[argc]) argc++;
                ALLOC_ARRAY(argv2, argc + 1);
                argv2[0] = (char *)cmd; /* full path to the script file */
                memcpy(&argv2[1], &argv[1], sizeof(*argv) * argc);
+               exec_id = trace2_exec(prog, argv2);
                pid = mingw_spawnv(prog, argv2, 1);
                if (pid >= 0) {
                        int status;
                        if (waitpid(pid, &status, 0) < 0)
                                status = 255;
+                       trace2_exec_result(exec_id, status);
                        exit(status);
                }
+               trace2_exec_result(exec_id, -1);
                pid = 1;        /* indicate that we tried but failed */
                free(prog);
                free(argv2);
@@ -1576,12 +1580,17 @@ int mingw_execv(const char *cmd, char *const *argv)
        /* check if git_command is a shell script */
        if (!try_shell_exec(cmd, argv)) {
                int pid, status;
+               int exec_id;
 
+               exec_id = trace2_exec(cmd, (const char **)argv);
                pid = mingw_spawnv(cmd, (const char **)argv, 0);
-               if (pid < 0)
+               if (pid < 0) {
+                       trace2_exec_result(exec_id, -1);
                        return -1;
+               }
                if (waitpid(pid, &status, 0) < 0)
                        status = 255;
+               trace2_exec_result(exec_id, status);
                exit(status);
        }
        return -1;
index 30d9fb3e36274657e5d2a63ef2f5eb3e1c55ce61..4d73f8aa9d0d0937b1fcbe8d854485327fc3896c 100644 (file)
@@ -147,8 +147,7 @@ static inline int fcntl(int fd, int cmd, ...)
        errno = EINVAL;
        return -1;
 }
-/* bash cannot reliably detect negative return codes as failure */
-#define exit(code) exit((code) & 0xff)
+
 #define sigemptyset(x) (void)0
 static inline int sigaddset(sigset_t *set, int signum)
 { return 0; }
diff --git a/compat/win32/trace2_win32_process_info.c b/compat/win32/trace2_win32_process_info.c
new file mode 100644 (file)
index 0000000..52bd620
--- /dev/null
@@ -0,0 +1,147 @@
+#include "../../cache.h"
+#include "../../json-writer.h"
+#include <Psapi.h>
+#include <tlHelp32.h>
+
+/*
+ * An arbitrarily chosen value to limit the size of the ancestor
+ * array built in git_processes().
+ */
+#define NR_PIDS_LIMIT 10
+
+/*
+ * Find the process data for the given PID in the given snapshot
+ * and update the PROCESSENTRY32 data.
+ */
+static int find_pid(DWORD pid, HANDLE hSnapshot, PROCESSENTRY32 *pe32)
+{
+       pe32->dwSize = sizeof(PROCESSENTRY32);
+
+       if (Process32First(hSnapshot, pe32)) {
+               do {
+                       if (pe32->th32ProcessID == pid)
+                               return 1;
+               } while (Process32Next(hSnapshot, pe32));
+       }
+       return 0;
+}
+
+/*
+ * Accumulate JSON array of our parent processes:
+ *     [
+ *         exe-name-parent,
+ *         exe-name-grand-parent,
+ *         ...
+ *     ]
+ *
+ * Note: we only report the filename of the process executable; the
+ *       only way to get its full pathname is to use OpenProcess()
+ *       and GetModuleFileNameEx() or QueryfullProcessImageName()
+ *       and that seems rather expensive (on top of the cost of
+ *       getting the snapshot).
+ *
+ * Note: we compute the set of parent processes by walking the PPID
+ *       link in each visited PROCESSENTRY32 record.  This search
+ *       stops when an ancestor process is not found in the snapshot
+ *       (because it exited before the current or intermediate parent
+ *       process exited).
+ *
+ *       This search may compute an incorrect result if the PPID link
+ *       refers to the PID of an exited parent and that PID has been
+ *       recycled and given to a new unrelated process.
+ *
+ *       Worse, it is possible for a child or descendant of the
+ *       current process to be given the recycled PID and cause a
+ *       PPID-cycle.  This would cause an infinite loop building our
+ *       parent process array.
+ *
+ * Note: for completeness, the "System Idle" process has PID=0 and
+ *       PPID=0 and could cause another PPID-cycle.  We don't expect
+ *       Git to be a descendant of the idle process, but because of
+ *       PID recycling, it might be possible to get a PPID link value
+ *       of 0.  This too would cause an infinite loop.
+ *
+ * Therefore, we keep an array of the visited PPIDs to guard against
+ * cycles.
+ *
+ * We use a fixed-size array rather than ALLOC_GROW to keep things
+ * simple and avoid the alloc/realloc overhead.  It is OK if we
+ * truncate the search and return a partial answer.
+ */
+static void get_processes(struct json_writer *jw, HANDLE hSnapshot)
+{
+       PROCESSENTRY32 pe32;
+       DWORD pid;
+       DWORD pid_list[NR_PIDS_LIMIT];
+       int k, nr_pids = 0;
+
+       pid = GetCurrentProcessId();
+       while (find_pid(pid, hSnapshot, &pe32)) {
+               /* Only report parents. Omit self from the JSON output. */
+               if (nr_pids)
+                       jw_array_string(jw, pe32.szExeFile);
+
+               /* Check for cycle in snapshot. (Yes, it happened.) */
+               for (k = 0; k < nr_pids; k++)
+                       if (pid == pid_list[k]) {
+                               jw_array_string(jw, "(cycle)");
+                               return;
+                       }
+
+               if (nr_pids == NR_PIDS_LIMIT) {
+                       jw_array_string(jw, "(truncated)");
+                       return;
+               }
+
+               pid_list[nr_pids++] = pid;
+
+               pid = pe32.th32ParentProcessID;
+       }
+}
+
+/*
+ * Emit JSON data for the current and parent processes.  Individual
+ * trace2 targets can decide how to actually print it.
+ */
+static void get_ancestry(void)
+{
+       HANDLE hSnapshot = CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, 0);
+
+       if (hSnapshot != INVALID_HANDLE_VALUE) {
+               struct json_writer jw = JSON_WRITER_INIT;
+
+               jw_array_begin(&jw, 0);
+               get_processes(&jw, hSnapshot);
+               jw_end(&jw);
+
+               trace2_data_json("process", the_repository, "windows/ancestry",
+                                &jw);
+
+               jw_release(&jw);
+               CloseHandle(hSnapshot);
+       }
+}
+
+/*
+ * Is a debugger attached to the current process?
+ *
+ * This will catch debug runs (where the debugger started the process).
+ * This is the normal case.  Since this code is called during our startup,
+ * it will not report instances where a debugger is attached dynamically
+ * to a running git process, but that is relatively rare.
+ */
+static void get_is_being_debugged(void)
+{
+       if (IsDebuggerPresent())
+               trace2_data_intmax("process", the_repository,
+                                  "windows/debugger_present", 1);
+}
+
+void trace2_collect_process_info(void)
+{
+       if (!trace2_is_enabled())
+               return;
+
+       get_is_being_debugged();
+       get_ancestry();
+}
index 921f73dc962e578e9aed7ae11ae6746f4f6b75c8..0f0cdd8c0fc9ee40c1f56d1935c1816eb03601ad 100644 (file)
--- a/config.c
+++ b/config.c
@@ -2657,6 +2657,8 @@ int git_config_set_gently(const char *key, const char *value)
 void git_config_set(const char *key, const char *value)
 {
        git_config_set_multivar(key, value, NULL, 0);
+
+       trace2_cmd_set_config(key, value);
 }
 
 /*
index b37fa8424c88cae23abf02f8276e8b4f6ffef19a..c8b0e34c3144da9ac384a56b1d2903d4d9e70ec9 100644 (file)
@@ -393,6 +393,7 @@ ifeq ($(uname_S),Windows)
        BASIC_CFLAGS = -nologo -I. -I../zlib -Icompat/vcbuild -Icompat/vcbuild/include -DWIN32 -D_CONSOLE -DHAVE_STRING_H -D_CRT_SECURE_NO_WARNINGS -D_CRT_NONSTDC_NO_DEPRECATE
        COMPAT_OBJS = compat/msvc.o compat/winansi.o \
                compat/win32/pthread.o compat/win32/syslog.o \
+               compat/win32/trace2_win32_process_info.o \
                compat/win32/dirent.o
        COMPAT_CFLAGS = -D__USE_MINGW_ACCESS -DNOGDI -DHAVE_STRING_H -Icompat -Icompat/regex -Icompat/win32 -DSTRIP_EXTENSION=\".exe\"
        BASIC_LDFLAGS = -IGNORE:4217 -IGNORE:4049 -NOLOGO -SUBSYSTEM:CONSOLE
@@ -546,6 +547,7 @@ ifneq (,$(findstring MINGW,$(uname_S)))
        COMPAT_CFLAGS += -DNOGDI -Icompat -Icompat/win32
        COMPAT_CFLAGS += -DSTRIP_EXTENSION=\".exe\"
        COMPAT_OBJS += compat/mingw.o compat/winansi.o \
+               compat/win32/trace2_win32_process_info.o \
                compat/win32/path-utils.o \
                compat/win32/pthread.o compat/win32/syslog.o \
                compat/win32/dirent.o
index 4813f005ab05279a72ef2894cfae8887965d9640..2778481264d0e1fdd8864743fc860ef63718524e 100644 (file)
--- a/connect.c
+++ b/connect.c
@@ -1248,6 +1248,7 @@ struct child_process *git_connect(int fd[2], const char *url,
                conn = NULL;
        } else if (protocol == PROTO_GIT) {
                conn = git_connect_git(fd, hostandport, path, prog, version, flags);
+               conn->trace2_child_class = "transport/git";
        } else {
                struct strbuf cmd = STRBUF_INIT;
                const char *const *var;
@@ -1290,9 +1291,11 @@ struct child_process *git_connect(int fd[2], const char *url,
                                strbuf_release(&cmd);
                                return NULL;
                        }
+                       conn->trace2_child_class = "transport/ssh";
                        fill_ssh_args(conn, ssh_host, port, version, flags);
                } else {
                        transport_check_allowed("file");
+                       conn->trace2_child_class = "transport/file";
                        if (version > 0) {
                                argv_array_pushf(&conn->env_array, GIT_PROTOCOL_ENVIRONMENT "=version=%d",
                                                 version);
index c985eee1f9d1c7307b7f533cb2d38de5a42ccb23..71547674ab4e885bd06560a547e78fddb0849158 100644 (file)
--- a/editor.c
+++ b/editor.c
@@ -78,6 +78,7 @@ static int launch_specified_editor(const char *editor, const char *path,
                p.argv = args;
                p.env = env;
                p.use_shell = 1;
+               p.trace2_child_class = "editor";
                if (start_command(&p) < 0)
                        return error("unable to start editor '%s'", editor);
 
index 4f81f443105f071e488a0436b7fe0579e22bc816..7deeab30397cf2edbee622717acd94de87256c8e 100644 (file)
@@ -209,6 +209,8 @@ static int git_get_exec_path(struct strbuf *buf, const char *argv0)
                return -1;
        }
 
+       trace2_cmd_path(buf->buf);
+
        return 0;
 }
 
index 6573808ebd991b52eca7cc644af4c9611b9c3747..31b47932bd5144f306a9aa1b122fdf3cb0886284 100644 (file)
@@ -1259,6 +1259,13 @@ static inline int is_missing_file_error(int errno_)
 
 extern int cmd_main(int, const char **);
 
+/*
+ * Intercept all calls to exit() and route them to trace2 to
+ * optionally emit a message before calling the real exit().
+ */
+int trace2_cmd_exit_fl(const char *file, int line, int code);
+#define exit(code) exit(trace2_cmd_exit_fl(__FILE__, __LINE__, (code)))
+
 /*
  * You can mark a stack variable with UNLEAK(var) to avoid it being
  * reported as a leak by tools like LSAN or valgrind. The argument
diff --git a/git.c b/git.c
index 2dd588674f621e2df2af1a3833c2cb3fa8417de4..2014aab6b83c61695d50ac39a18864a8d77858e0 100644 (file)
--- a/git.c
+++ b/git.c
@@ -147,16 +147,20 @@ static int handle_options(const char ***argv, int *argc, int *envchanged)
                                git_set_exec_path(cmd + 1);
                        else {
                                puts(git_exec_path());
+                               trace2_cmd_name("_query_");
                                exit(0);
                        }
                } else if (!strcmp(cmd, "--html-path")) {
                        puts(system_path(GIT_HTML_PATH));
+                       trace2_cmd_name("_query_");
                        exit(0);
                } else if (!strcmp(cmd, "--man-path")) {
                        puts(system_path(GIT_MAN_PATH));
+                       trace2_cmd_name("_query_");
                        exit(0);
                } else if (!strcmp(cmd, "--info-path")) {
                        puts(system_path(GIT_INFO_PATH));
+                       trace2_cmd_name("_query_");
                        exit(0);
                } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
                        use_pager = 1;
@@ -285,6 +289,7 @@ static int handle_options(const char ***argv, int *argc, int *envchanged)
                        (*argv)++;
                        (*argc)--;
                } else if (skip_prefix(cmd, "--list-cmds=", &cmd)) {
+                       trace2_cmd_name("_query_");
                        if (!strcmp(cmd, "parseopt")) {
                                struct string_list list = STRING_LIST_INIT_DUP;
                                int i;
@@ -332,9 +337,14 @@ static int handle_alias(int *argcp, const char ***argv)
                        commit_pager_choice();
 
                        child.use_shell = 1;
+                       child.trace2_child_class = "shell_alias";
                        argv_array_push(&child.args, alias_string + 1);
                        argv_array_pushv(&child.args, (*argv) + 1);
 
+                       trace2_cmd_alias(alias_command, child.args.argv);
+                       trace2_cmd_list_config();
+                       trace2_cmd_name("_run_shell_alias_");
+
                        ret = run_command(&child);
                        if (ret >= 0)   /* normal exit */
                                exit(ret);
@@ -369,6 +379,9 @@ static int handle_alias(int *argcp, const char ***argv)
                /* insert after command name */
                memcpy(new_argv + count, *argv + 1, sizeof(char *) * *argcp);
 
+               trace2_cmd_alias(alias_command, new_argv);
+               trace2_cmd_list_config();
+
                *argv = new_argv;
                *argcp += count - 1;
 
@@ -417,6 +430,8 @@ static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
                setup_work_tree();
 
        trace_argv_printf(argv, "trace: built-in: git");
+       trace2_cmd_name(p->cmd);
+       trace2_cmd_list_config();
 
        validate_cache_entries(the_repository->index);
        status = p->fn(argc, argv, prefix);
@@ -666,7 +681,14 @@ static void execv_dashed_external(const char **argv)
        cmd.clean_on_exit = 1;
        cmd.wait_after_clean = 1;
        cmd.silent_exec_failure = 1;
+       cmd.trace2_child_class = "dashed";
 
+       trace2_cmd_name("_run_dashed_");
+
+       /*
+        * The code in run_command() logs trace2 child_start/child_exit
+        * events, so we do not need to report exec/exec_result events here.
+        */
        trace_argv_printf(cmd.args.argv, "trace: exec:");
 
        /*
@@ -676,6 +698,12 @@ static void execv_dashed_external(const char **argv)
         * the program.
         */
        status = run_command(&cmd);
+
+       /*
+        * If the child process ran and we are now going to exit, emit a
+        * generic string as our trace2 command verb to indicate that we
+        * launched a dashed command.
+        */
        if (status >= 0)
                exit(status);
        else if (errno != ENOENT)
@@ -701,6 +729,43 @@ static int run_argv(int *argcp, const char ***argv)
                if (!done_alias)
                        handle_builtin(*argcp, *argv);
 
+#if 0 // TODO In GFW, need to amend a7924b655e940b06cb547c235d6bed9767929673 to include trace2_ and _tr2 lines.
+               else if (get_builtin(**argv)) {
+                       struct argv_array args = ARGV_ARRAY_INIT;
+                       int i;
+
+                       /*
+                        * The current process is committed to launching a
+                        * child process to run the command named in (**argv)
+                        * and exiting.  Log a generic string as the trace2
+                        * command verb to indicate this.  Note that the child
+                        * process will log the actual verb when it runs.
+                        */
+                       trace2_cmd_name("_run_git_alias_");
+
+                       if (get_super_prefix())
+                               die("%s doesn't support --super-prefix", **argv);
+
+                       commit_pager_choice();
+
+                       argv_array_push(&args, "git");
+                       for (i = 0; i < *argcp; i++)
+                               argv_array_push(&args, (*argv)[i]);
+
+                       trace_argv_printf(args.argv, "trace: exec:");
+
+                       /*
+                        * if we fail because the command is not found, it is
+                        * OK to return. Otherwise, we just pass along the status code.
+                        */
+                       i = run_command_v_opt_tr2(args.argv, RUN_SILENT_EXEC_FAILURE |
+                                                 RUN_CLEAN_ON_EXIT, "git_alias");
+                       if (i >= 0 || errno != ENOENT)
+                               exit(i);
+                       die("could not execute builtin %s", **argv);
+               }
+#endif // a7924b655e940b06cb547c235d6bed9767929673
+
                /* .. then try the external ones */
                execv_dashed_external(*argv);
 
diff --git a/pager.c b/pager.c
index a768797fcfcc44de4dbe4d983a45ade8c81b2e1c..4168460ae92ceb18b4a31c4d0524b411231cf137 100644 (file)
--- a/pager.c
+++ b/pager.c
@@ -100,6 +100,7 @@ void prepare_pager_args(struct child_process *pager_process, const char *pager)
        argv_array_push(&pager_process->args, pager);
        pager_process->use_shell = 1;
        setup_pager_env(&pager_process->env_array);
+       pager_process->trace2_child_class = "pager";
 }
 
 void setup_pager(void)
index 441537032f65bcbb0182f8c7f82d78e86afc3022..4dc6de1b55b0a6047e49f188b28c431f0167d7ef 100644 (file)
@@ -2226,6 +2226,16 @@ int do_read_index(struct index_state *istate, const char *path, int must_exist)
                load_index_extensions(&p);
        }
        munmap((void *)mmap, mmap_size);
+
+       /*
+        * TODO trace2: replace "the_repository" with the actual repo instance
+        * that is associated with the given "istate".
+        */
+       trace2_data_intmax("index", the_repository, "read/version",
+                          istate->version);
+       trace2_data_intmax("index", the_repository, "read/cache_nr",
+                          istate->cache_nr);
+
        return istate->cache_nr;
 
 unmap:
@@ -2257,9 +2267,17 @@ int read_index_from(struct index_state *istate, const char *path,
        if (istate->initialized)
                return istate->cache_nr;
 
+       /*
+        * TODO trace2: replace "the_repository" with the actual repo instance
+        * that is associated with the given "istate".
+        */
+       trace2_region_enter_printf("index", "do_read_index", the_repository,
+                                  "%s", path);
        trace_performance_enter();
        ret = do_read_index(istate, path, 0);
        trace_performance_leave("read cache %s", path);
+       trace2_region_leave_printf("index", "do_read_index", the_repository,
+                                  "%s", path);
 
        split_index = istate->split_index;
        if (!split_index || is_null_oid(&split_index->base_oid)) {
@@ -2275,7 +2293,11 @@ int read_index_from(struct index_state *istate, const char *path,
 
        base_oid_hex = oid_to_hex(&split_index->base_oid);
        base_path = xstrfmt("%s/sharedindex.%s", gitdir, base_oid_hex);
+       trace2_region_enter_printf("index", "shared/do_read_index",
+                                  the_repository, "%s", base_path);
        ret = do_read_index(split_index->base, base_path, 1);
+       trace2_region_leave_printf("index", "shared/do_read_index",
+                                  the_repository, "%s", base_path);
        if (!oideq(&split_index->base_oid, &split_index->base->oid))
                die(_("broken index, expect %s in %s, got %s"),
                    base_oid_hex, base_path,
@@ -2983,6 +3005,16 @@ static int do_write_index(struct index_state *istate, struct tempfile *tempfile,
        istate->timestamp.sec = (unsigned int)st.st_mtime;
        istate->timestamp.nsec = ST_MTIME_NSEC(st);
        trace_performance_since(start, "write index, changed mask = %x", istate->cache_changed);
+
+       /*
+        * TODO trace2: replace "the_repository" with the actual repo instance
+        * that is associated with the given "istate".
+        */
+       trace2_data_intmax("index", the_repository, "write/version",
+                          istate->version);
+       trace2_data_intmax("index", the_repository, "write/cache_nr",
+                          istate->cache_nr);
+
        return 0;
 }
 
@@ -3002,7 +3034,18 @@ static int commit_locked_index(struct lock_file *lk)
 static int do_write_locked_index(struct index_state *istate, struct lock_file *lock,
                                 unsigned flags)
 {
-       int ret = do_write_index(istate, lock->tempfile, 0);
+       int ret;
+
+       /*
+        * TODO trace2: replace "the_repository" with the actual repo instance
+        * that is associated with the given "istate".
+        */
+       trace2_region_enter_printf("index", "do_write_index", the_repository,
+                                  "%s", lock->tempfile->filename.buf);
+       ret = do_write_index(istate, lock->tempfile, 0);
+       trace2_region_leave_printf("index", "do_write_index", the_repository,
+                                  "%s", lock->tempfile->filename.buf);
+
        if (ret)
                return ret;
        if (flags & COMMIT_LOCK)
@@ -3087,7 +3130,13 @@ static int write_shared_index(struct index_state *istate,
        int ret;
 
        move_cache_to_base_index(istate);
+
+       trace2_region_enter_printf("index", "shared/do_write_index",
+                                  the_repository, "%s", (*temp)->filename.buf);
        ret = do_write_index(si->base, *temp, 1);
+       trace2_region_enter_printf("index", "shared/do_write_index",
+                                  the_repository, "%s", (*temp)->filename.buf);
+
        if (ret)
                return ret;
        ret = adjust_shared_perm(get_tempfile_path(*temp));
index bb7421023ba584d59592124aa6f3ff2028bc5356..aad02dcc74b61d0701f1dd599339430df90f8465 100644 (file)
@@ -1385,6 +1385,13 @@ int cmd_main(int argc, const char **argv)
        string_list_init(&options.deepen_not, 1);
        string_list_init(&options.push_options, 1);
 
+       /*
+        * Just report "remote-curl" here (folding all the various aliases
+        * ("git-remote-http", "git-remote-https", and etc.) here since they
+        * are all just copies of the same actual executable.
+        */
+       trace2_cmd_name("remote-curl");
+
        remote = remote_get(argv[1]);
 
        if (argc > 2) {
index 65e6f8b8fdfcf89e5c86cbee9590aa555f7b0b47..5cad2dcc86a530ab088cda98a5c64bbe78102038 100644 (file)
@@ -126,6 +126,8 @@ static int repo_init_gitdir(struct repository *repo, const char *gitdir)
 void repo_set_worktree(struct repository *repo, const char *path)
 {
        repo->worktree = real_pathdup(path, 1);
+
+       trace2_def_repo(repo);
 }
 
 static int read_and_verify_repository_format(struct repository_format *format,
index 8981649d43736ee283fcd23cd3185288252d5357..4fb6a5885f794dea9ff7a1ecf37f27bc34e4d218 100644 (file)
@@ -92,6 +92,9 @@ struct repository {
        /* Repository's current hash algorithm, as serialized on disk. */
        const struct git_hash_algo *hash_algo;
 
+       /* A unique-id for tracing purposes. */
+       int trace2_repo_id;
+
        /* Configurations */
 
        /* Indicate if a repository has a different 'commondir' from 'gitdir' */
index 3db26b7b0e2ab9b6b615387b36a2cd6b64800e9e..3449db319b95d17133abcdb39048730a4c922515 100644 (file)
@@ -219,9 +219,29 @@ static int exists_in_PATH(const char *file)
 
 int sane_execvp(const char *file, char * const argv[])
 {
+#ifndef GIT_WINDOWS_NATIVE
+       /*
+        * execvp() doesn't return, so we all we can do is tell trace2
+        * what we are about to do and let it leave a hint in the log
+        * (unless of course the execvp() fails).
+        *
+        * we skip this for Windows because the compat layer already
+        * has to emulate the execvp() call anyway.
+        */
+       int exec_id = trace2_exec(file, (const char **)argv);
+#endif
+
        if (!execvp(file, argv))
                return 0; /* cannot happen ;-) */
 
+#ifndef GIT_WINDOWS_NATIVE
+       {
+               int ec = errno;
+               trace2_exec_result(exec_id, ec);
+               errno = ec;
+       }
+#endif
+
        /*
         * When a command can't be found because one of the directories
         * listed in $PATH is unsearchable, execvp reports EACCES, but
@@ -712,6 +732,7 @@ int start_command(struct child_process *cmd)
                cmd->err = fderr[0];
        }
 
+       trace2_child_start(cmd);
        trace_run_command(cmd);
 
        fflush(NULL);
@@ -926,6 +947,8 @@ int start_command(struct child_process *cmd)
 #endif
 
        if (cmd->pid < 0) {
+               trace2_child_exit(cmd, -1);
+
                if (need_in)
                        close_pair(fdin);
                else if (cmd->in)
@@ -964,13 +987,16 @@ int start_command(struct child_process *cmd)
 int finish_command(struct child_process *cmd)
 {
        int ret = wait_or_whine(cmd->pid, cmd->argv[0], 0);
+       trace2_child_exit(cmd, ret);
        child_process_clear(cmd);
        return ret;
 }
 
 int finish_command_in_signal(struct child_process *cmd)
 {
-       return wait_or_whine(cmd->pid, cmd->argv[0], 1);
+       int ret = wait_or_whine(cmd->pid, cmd->argv[0], 1);
+       trace2_child_exit(cmd, ret);
+       return ret;
 }
 
 
@@ -992,7 +1018,18 @@ int run_command_v_opt(const char **argv, int opt)
        return run_command_v_opt_cd_env(argv, opt, NULL, NULL);
 }
 
+int run_command_v_opt_tr2(const char **argv, int opt, const char *tr2_class)
+{
+       return run_command_v_opt_cd_env_tr2(argv, opt, NULL, NULL, tr2_class);
+}
+
 int run_command_v_opt_cd_env(const char **argv, int opt, const char *dir, const char *const *env)
+{
+       return run_command_v_opt_cd_env_tr2(argv, opt, dir, env, NULL);
+}
+
+int run_command_v_opt_cd_env_tr2(const char **argv, int opt, const char *dir,
+                                const char *const *env, const char *tr2_class)
 {
        struct child_process cmd = CHILD_PROCESS_INIT;
        cmd.argv = argv;
@@ -1004,6 +1041,7 @@ int run_command_v_opt_cd_env(const char **argv, int opt, const char *dir, const
        cmd.clean_on_exit = opt & RUN_CLEAN_ON_EXIT ? 1 : 0;
        cmd.dir = dir;
        cmd.env = env;
+       cmd.trace2_child_class = tr2_class;
        return run_command(&cmd);
 }
 
@@ -1319,6 +1357,7 @@ int run_hook_ve(const char *const *env, const char *name, va_list args)
        hook.env = env;
        hook.no_stdin = 1;
        hook.stdout_to_stderr = 1;
+       hook.trace2_hook_name = name;
 
        return run_command(&hook);
 }
@@ -1807,3 +1846,21 @@ int run_processes_parallel(int n,
        pp_cleanup(&pp);
        return 0;
 }
+
+int run_processes_parallel_tr2(int n, get_next_task_fn get_next_task,
+                              start_failure_fn start_failure,
+                              task_finished_fn task_finished, void *pp_cb,
+                              const char *tr2_category, const char *tr2_label)
+{
+       int result;
+
+       trace2_region_enter_printf(tr2_category, tr2_label, NULL, "max:%d",
+                                  ((n < 1) ? online_cpus() : n));
+
+       result = run_processes_parallel(n, get_next_task, start_failure,
+                                       task_finished, pp_cb);
+
+       trace2_region_leave(tr2_category, tr2_label, NULL);
+
+       return result;
+}
index 68f5369fc2d432e8b4b504e9625b541056814216..a6950691c042e6234b46c0b8c94f5312da58f734 100644 (file)
@@ -10,6 +10,12 @@ struct child_process {
        struct argv_array args;
        struct argv_array env_array;
        pid_t pid;
+
+       int trace2_child_id;
+       uint64_t trace2_child_us_start;
+       const char *trace2_child_class;
+       const char *trace2_hook_name;
+
        /*
         * Using .in, .out, .err:
         * - Specify 0 for no redirections (child inherits stdin, stdout,
@@ -73,12 +79,14 @@ extern int run_hook_ve(const char *const *env, const char *name, va_list args);
 #define RUN_USING_SHELL 16
 #define RUN_CLEAN_ON_EXIT 32
 int run_command_v_opt(const char **argv, int opt);
-
+int run_command_v_opt_tr2(const char **argv, int opt, const char *tr2_class);
 /*
  * env (the environment) is to be formatted like environ: "VAR=VALUE".
  * To unset an environment variable use just "VAR".
  */
 int run_command_v_opt_cd_env(const char **argv, int opt, const char *dir, const char *const *env);
+int run_command_v_opt_cd_env_tr2(const char **argv, int opt, const char *dir,
+                                const char *const *env, const char *tr2_class);
 
 /**
  * Execute the given command, sending "in" to its stdin, and capturing its
@@ -220,5 +228,8 @@ int run_processes_parallel(int n,
                           start_failure_fn,
                           task_finished_fn,
                           void *pp_cb);
+int run_processes_parallel_tr2(int n, get_next_task_fn, start_failure_fn,
+                              task_finished_fn, void *pp_cb,
+                              const char *tr2_category, const char *tr2_label);
 
 #endif
index 3209cdefd1d9287ecd8c077cc254fd63a600112c..95dda23eee450d1d60a70434d254071c6c05146b 100644 (file)
@@ -1103,6 +1103,7 @@ static int run_rewrite_hook(const struct object_id *oldoid,
        proc.argv = argv;
        proc.in = -1;
        proc.stdout_to_stderr = 1;
+       proc.trace2_hook_name = "post-rewrite";
 
        code = start_command(&proc);
        if (code)
@@ -3786,6 +3787,7 @@ static int pick_commits(struct repository *r,
                                hook.in = open(rebase_path_rewritten_list(),
                                        O_RDONLY);
                                hook.stdout_to_stderr = 1;
+                               hook.trace2_hook_name = "post-rewrite";
                                argv_array_push(&hook.args, post_rewrite_hook);
                                argv_array_push(&hook.args, "rebase");
                                /* we don't care if this hook failed */
index 09c6b445b9631202c69d2a1804a757148b43beb0..cecfdd36c7e696dce6188aea3398fbe8857d798b 100644 (file)
@@ -14,6 +14,7 @@
  */
 
 #include "git-compat-util.h"
+#include "trace2.h"
 
 /* Substitution of environment variables in shell format strings.
    Copyright (C) 2003-2007 Free Software Foundation, Inc.
@@ -67,6 +68,8 @@ cmd_main (int argc, const char *argv[])
   /* Default values for command line options.  */
   /* unsigned short int show_variables = 0; */
 
+  trace2_cmd_name("sh-i18n--envsubst");
+
   switch (argc)
        {
        case 1:
index 8d2a1707cfe1a7d0fb6b589f0857a6389a8a3d70..3f4af935557c5ee22b0b1b9b43d2778161210765 100644 (file)
@@ -88,6 +88,7 @@ int subprocess_start(struct hashmap *hashmap, struct subprocess_entry *entry, co
        process->out = -1;
        process->clean_on_exit = 1;
        process->clean_on_exit_handler = subprocess_exit_handler;
+       process->trace2_child_class = "subprocess";
 
        err = start_command(process);
        if (err) {
index 934ecfa2943bcb5ee87e7ac431b5332a5f3adcde..174003a847aa9a8c6de666fc24ece9213ccb0921 100644 (file)
@@ -1609,11 +1609,12 @@ int fetch_populated_submodules(struct repository *r,
 
        calculate_changed_submodule_paths(r, &spf.changed_submodule_names);
        string_list_sort(&spf.changed_submodule_names);
-       run_processes_parallel(max_parallel_jobs,
-                              get_next_submodule,
-                              fetch_start_failure,
-                              fetch_finish,
-                              &spf);
+       run_processes_parallel_tr2(max_parallel_jobs,
+                                  get_next_submodule,
+                                  fetch_start_failure,
+                                  fetch_finish,
+                                  &spf,
+                                  "submodule", "parallel/fetch");
 
        argv_array_clear(&spf.args);
 out:
index 47fee660b86a6e6977735e2c940de79d4330d519..cc88fba05752cbf67c2669c219cc0a65d4a354ee 100644 (file)
@@ -2,6 +2,7 @@
 #include "cache.h"
 #include "parse-options.h"
 #include "string-list.h"
+#include "trace2.h"
 
 static int boolean = 0;
 static int integer = 0;
@@ -153,6 +154,8 @@ int cmd__parse_options(int argc, const char **argv)
        int i;
        int ret = 0;
 
+       trace2_cmd_name("_parse_");
+
        argc = parse_options(argc, (const char **)argv, prefix, options, usage, 0);
 
        if (length_cb.called) {
index 99db7409b812898b461e75c8bd14e910f9e10e5c..53c06932c45c17bcb2981c9b1cc081df8135dded 100644 (file)
@@ -1,5 +1,6 @@
 #include "git-compat-util.h"
 #include "test-tool.h"
+#include "trace2.h"
 
 struct test_cmd {
        const char *name;
@@ -51,6 +52,7 @@ static struct test_cmd cmds[] = {
        { "submodule-config", cmd__submodule_config },
        { "submodule-nested-repo-config", cmd__submodule_nested_repo_config },
        { "subprocess", cmd__subprocess },
+       { "trace2", cmd__trace2 },
        { "urlmatch-normalization", cmd__urlmatch_normalization },
        { "xml-encode", cmd__xml_encode },
        { "wildmatch", cmd__wildmatch },
@@ -82,6 +84,8 @@ int cmd_main(int argc, const char **argv)
                if (!strcmp(cmds[i].name, argv[1])) {
                        argv++;
                        argc--;
+                       trace2_cmd_name(cmds[i].name);
+                       trace2_cmd_list_config();
                        return cmds[i].fn(argc, argv);
                }
        }
index 25abed1cf2acc9e84cf1ed78eebe97c7c4d728ca..ffab4d19d701e79cac1283a749e03ae8cf437e2e 100644 (file)
@@ -48,6 +48,7 @@ int cmd__string_list(int argc, const char **argv);
 int cmd__submodule_config(int argc, const char **argv);
 int cmd__submodule_nested_repo_config(int argc, const char **argv);
 int cmd__subprocess(int argc, const char **argv);
+int cmd__trace2(int argc, const char **argv);
 int cmd__urlmatch_normalization(int argc, const char **argv);
 int cmd__xml_encode(int argc, const char **argv);
 int cmd__wildmatch(int argc, const char **argv);
diff --git a/t/helper/test-trace2.c b/t/helper/test-trace2.c
new file mode 100644 (file)
index 0000000..197819c
--- /dev/null
@@ -0,0 +1,273 @@
+#include "test-tool.h"
+#include "cache.h"
+#include "argv-array.h"
+#include "run-command.h"
+#include "exec-cmd.h"
+#include "config.h"
+
+typedef int(fn_unit_test)(int argc, const char **argv);
+
+struct unit_test {
+       fn_unit_test *ut_fn;
+       const char *ut_name;
+       const char *ut_usage;
+};
+
+#define MyOk 0
+#define MyError 1
+
+static int get_i(int *p_value, const char *data)
+{
+       char *endptr;
+
+       if (!data || !*data)
+               return MyError;
+
+       *p_value = strtol(data, &endptr, 10);
+       if (*endptr || errno == ERANGE)
+               return MyError;
+
+       return MyOk;
+}
+
+/*
+ * Cause process to exit with the requested value via "return".
+ *
+ * Rely on test-tool.c:cmd_main() to call trace2_cmd_exit()
+ * with our result.
+ *
+ * Test harness can confirm:
+ * [] the process-exit value.
+ * [] the "code" field in the "exit" trace2 event.
+ * [] the "code" field in the "atexit" trace2 event.
+ * [] the "name" field in the "cmd_name" trace2 event.
+ * [] "def_param" events for all of the "interesting" pre-defined
+ * config settings.
+ */
+static int ut_001return(int argc, const char **argv)
+{
+       int rc;
+
+       if (get_i(&rc, argv[0]))
+               die("expect <exit_code>");
+
+       return rc;
+}
+
+/*
+ * Cause the process to exit with the requested value via "exit()".
+ *
+ * Test harness can confirm:
+ * [] the "code" field in the "exit" trace2 event.
+ * [] the "code" field in the "atexit" trace2 event.
+ * [] the "name" field in the "cmd_name" trace2 event.
+ * [] "def_param" events for all of the "interesting" pre-defined
+ * config settings.
+ */
+static int ut_002exit(int argc, const char **argv)
+{
+       int rc;
+
+       if (get_i(&rc, argv[0]))
+               die("expect <exit_code>");
+
+       exit(rc);
+}
+
+/*
+ * Send an "error" event with each value in argv.  Normally, git only issues
+ * a single "error" event immediately before issuing an "exit" event (such
+ * as in die() or BUG()), but multiple "error" events are allowed.
+ *
+ * Test harness can confirm:
+ * [] a trace2 "error" event for each value in argv.
+ * [] the "name" field in the "cmd_name" trace2 event.
+ * [] (optional) the file:line in the "exit" event refers to this function.
+ */
+static int ut_003error(int argc, const char **argv)
+{
+       int k;
+
+       if (!argv[0] || !*argv[0])
+               die("expect <error_message>");
+
+       for (k = 0; k < argc; k++)
+               error("%s", argv[k]);
+
+       return 0;
+}
+
+/*
+ * Run a child process and wait for it to finish and exit with its return code.
+ * test-tool trace2 004child [<child-command-line>]
+ *
+ * For example:
+ * test-tool trace2 004child git version
+ * test-tool trace2 004child test-tool trace2 001return 0
+ * test-tool trace2 004child test-tool trace2 004child test-tool trace2 004child
+ * test-tool trace2 004child git -c alias.xyz=version xyz
+ *
+ * Test harness can confirm:
+ * [] the "name" field in the "cmd_name" trace2 event.
+ * [] that the outer process has a single component SID (or depth "d0" in
+ *    the PERF stream).
+ * [] that "child_start" and "child_exit" events are generated for the child.
+ * [] if the child process is an instrumented executable:
+ *    [] that "version", "start", ..., "exit", and "atexit" events are
+ *       generated by the child process.
+ *    [] that the child process events have a multiple component SID (or
+ *       depth "dN+1" in the PERF stream).
+ * [] that the child exit code is propagated to the parent process "exit"
+ *    and "atexit" events..
+ * [] (optional) that the "t_abs" field in the child process "atexit" event
+ *    is less than the "t_rel" field in the "child_exit" event of the parent
+ *    process.
+ * [] if the child process is like the alias example above,
+ *    [] (optional) the child process attempts to run "git-xyx" as a dashed
+ *       command.
+ *    [] the child process emits an "alias" event with "xyz" => "version"
+ *    [] the child process runs "git version" as a child process.
+ *    [] the child process has a 3 component SID (or depth "d2" in the PERF
+ *       stream).
+ */
+static int ut_004child(int argc, const char **argv)
+{
+       int result;
+
+       /*
+        * Allow empty <child_command_line> so we can do arbitrarily deep
+        * command nesting and let the last one be null.
+        */
+       if (!argc)
+               return 0;
+
+       result = run_command_v_opt(argv, 0);
+       exit(result);
+}
+
+/*
+ * Exec a git command.  This may either create a child process (Windows)
+ * or replace the existing process.
+ * test-tool trace2 005exec <git_command_args>
+ *
+ * For example:
+ * test-tool trace2 005exec version
+ *
+ * Test harness can confirm (on Windows):
+ * [] the "name" field in the "cmd_name" trace2 event.
+ * [] that the outer process has a single component SID (or depth "d0" in
+ *    the PERF stream).
+ * [] that "exec" and "exec_result" events are generated for the child
+ *    process (since the Windows compatibility layer fakes an exec() with
+ *    a CreateProcess(), WaitForSingleObject(), and exit()).
+ * [] that the child process has multiple component SID (or depth "dN+1"
+ *    in the PERF stream).
+ *
+ * Test harness can confirm (on platforms with a real exec() function):
+ * [] TODO talk about process replacement and how it affects SID.
+ */
+static int ut_005exec(int argc, const char **argv)
+{
+       int result;
+
+       if (!argc)
+               return 0;
+
+       result = execv_git_cmd(argv);
+       return result;
+}
+
+static int ut_006data(int argc, const char **argv)
+{
+       const char *usage_error =
+               "expect <cat0> <k0> <v0> [<cat1> <k1> <v1> [...]]";
+
+       if (argc % 3 != 0)
+               die("%s", usage_error);
+
+       while (argc) {
+               if (!argv[0] || !*argv[0] || !argv[1] || !*argv[1] ||
+                   !argv[2] || !*argv[2])
+                       die("%s", usage_error);
+
+               trace2_data_string(argv[0], the_repository, argv[1], argv[2]);
+               argv += 3;
+               argc -= 3;
+       }
+
+       return 0;
+}
+
+/*
+ * Usage:
+ *     test-tool trace2 <ut_name_1> <ut_usage_1>
+ *     test-tool trace2 <ut_name_2> <ut_usage_2>
+ *     ...
+ */
+#define USAGE_PREFIX "test-tool trace2"
+
+/* clang-format off */
+static struct unit_test ut_table[] = {
+       { ut_001return,   "001return", "<exit_code>" },
+       { ut_002exit,     "002exit",   "<exit_code>" },
+       { ut_003error,    "003error",  "<error_message>+" },
+       { ut_004child,    "004child",  "[<child_command_line>]" },
+       { ut_005exec,     "005exec",   "<git_command_args>" },
+       { ut_006data,     "006data",   "[<category> <key> <value>]+" },
+};
+/* clang-format on */
+
+/* clang-format off */
+#define for_each_ut(k, ut_k)                   \
+       for (k = 0, ut_k = &ut_table[k];        \
+            k < ARRAY_SIZE(ut_table);          \
+            k++, ut_k = &ut_table[k])
+/* clang-format on */
+
+static int print_usage(void)
+{
+       int k;
+       struct unit_test *ut_k;
+
+       fprintf(stderr, "usage:\n");
+       for_each_ut (k, ut_k)
+               fprintf(stderr, "\t%s %s %s\n", USAGE_PREFIX, ut_k->ut_name,
+                       ut_k->ut_usage);
+
+       return 129;
+}
+
+/*
+ * Issue various trace2 events for testing.
+ *
+ * We assume that these trace2 routines has already been called:
+ *    [] trace2_initialize()      [common-main.c:main()]
+ *    [] trace2_cmd_start()       [common-main.c:main()]
+ *    [] trace2_cmd_name()        [test-tool.c:cmd_main()]
+ *    [] tracd2_cmd_list_config() [test-tool.c:cmd_main()]
+ * So that:
+ *    [] the various trace2 streams are open.
+ *    [] the process SID has been created.
+ *    [] the "version" event has been generated.
+ *    [] the "start" event has been generated.
+ *    [] the "cmd_name" event has been generated.
+ *    [] this writes various "def_param" events for interesting config values.
+ *
+ * We further assume that if we return (rather than exit()), trace2_cmd_exit()
+ * will be called by test-tool.c:cmd_main().
+ */
+int cmd__trace2(int argc, const char **argv)
+{
+       int k;
+       struct unit_test *ut_k;
+
+       argc--; /* skip over "trace2" arg */
+       argv++;
+
+       if (argc)
+               for_each_ut (k, ut_k)
+                       if (!strcmp(argv[0], ut_k->ut_name))
+                               return ut_k->ut_fn(argc - 1, argv + 1);
+
+       return print_usage();
+}
index 42a263cadafe55803bacf5e8bc071b9999618fc4..5e27604b24a7357575c1d51c7cafda9f5cb06471 100755 (executable)
@@ -93,6 +93,7 @@ test_expect_success 'No extra GIT_* on alias scripts' '
                sed -n \
                        -e "/^GIT_PREFIX=/d" \
                        -e "/^GIT_TEXTDOMAINDIR=/d" \
+                       -e "/^GIT_TR2_PARENT/d" \
                        -e "/^GIT_/s/=.*//p" |
                sort
        EOF
diff --git a/t/t0210-trace2-normal.sh b/t/t0210-trace2-normal.sh
new file mode 100755 (executable)
index 0000000..03a0aed
--- /dev/null
@@ -0,0 +1,135 @@
+#!/bin/sh
+
+test_description='test trace2 facility (normal target)'
+. ./test-lib.sh
+
+# Add t/helper directory to PATH so that we can use a relative
+# path to run nested instances of test-tool.exe (see 004child).
+# This helps with HEREDOC comparisons later.
+TTDIR="$GIT_BUILD_DIR/t/helper/" && export TTDIR
+PATH="$TTDIR:$PATH" && export PATH
+
+# Warning: use of 'test_cmp' may run test-tool.exe and/or git.exe
+# Warning: to do the actual diff/comparison, so the HEREDOCs here
+# Warning: only cover our actual calls to test-tool and/or git.
+# Warning: So you may see extra lines in artifact files when
+# Warning: interactively debugging.
+
+# Turn off any inherited trace2 settings for this test.
+unset GIT_TR2 GIT_TR2_PERF GIT_TR2_EVENT
+unset GIT_TR2_BRIEF
+unset GIT_TR2_CONFIG_PARAMS
+
+V=$(git version | sed -e 's/^git version //') && export V
+
+# There are multiple trace2 targets: normal, perf, and event.
+# Trace2 events will/can be written to each active target (subject
+# to whatever filtering that target decides to do).
+# This script tests the normal target in isolation.
+#
+# Defer setting GIT_TR2 until the actual command line we want to test
+# because hidden git and test-tool commands run by the test harness
+# can contaminate our output.
+
+# Enable "brief" feature which turns off "<clock> <file>:<line> " prefix.
+GIT_TR2_BRIEF=1 && export GIT_TR2_BRIEF
+
+# Basic tests of the trace2 normal stream.  Since this stream is used
+# primarily with printf-style debugging/tracing, we do limited testing
+# here.
+#
+# We do confirm the following API features:
+# [] the 'version <v>' event
+# [] the 'start <argv>' event
+# [] the 'cmd_name <name>' event
+# [] the 'exit <time> code:<code>' event
+# [] the 'atexit <time> code:<code>' event
+#
+# Fields of the form _FIELD_ are tokens that have been replaced (such
+# as the elapsed time).
+
+# Verb 001return
+#
+# Implicit return from cmd_<verb> function propagates <code>.
+
+test_expect_success 'normal stream, return code 0' '
+       test_when_finished "rm trace.normal actual expect" &&
+       GIT_TR2="$(pwd)/trace.normal" test-tool trace2 001return 0 &&
+       perl "$TEST_DIRECTORY/t0210/scrub_normal.perl" <trace.normal >actual &&
+       cat >expect <<-EOF &&
+               version $V
+               start _EXE_ trace2 001return 0
+               cmd_name trace2 (trace2)
+               exit elapsed:_TIME_ code:0
+               atexit elapsed:_TIME_ code:0
+       EOF
+       test_cmp expect actual
+'
+
+test_expect_success 'normal stream, return code 1' '
+       test_when_finished "rm trace.normal actual expect" &&
+       test_must_fail env GIT_TR2="$(pwd)/trace.normal" test-tool trace2 001return 1 &&
+       perl "$TEST_DIRECTORY/t0210/scrub_normal.perl" <trace.normal >actual &&
+       cat >expect <<-EOF &&
+               version $V
+               start _EXE_ trace2 001return 1
+               cmd_name trace2 (trace2)
+               exit elapsed:_TIME_ code:1
+               atexit elapsed:_TIME_ code:1
+       EOF
+       test_cmp expect actual
+'
+
+# Verb 002exit
+#
+# Explicit exit(code) from within cmd_<verb> propagates <code>.
+
+test_expect_success 'normal stream, exit code 0' '
+       test_when_finished "rm trace.normal actual expect" &&
+       GIT_TR2="$(pwd)/trace.normal" test-tool trace2 002exit 0 &&
+       perl "$TEST_DIRECTORY/t0210/scrub_normal.perl" <trace.normal >actual &&
+       cat >expect <<-EOF &&
+               version $V
+               start _EXE_ trace2 002exit 0
+               cmd_name trace2 (trace2)
+               exit elapsed:_TIME_ code:0
+               atexit elapsed:_TIME_ code:0
+       EOF
+       test_cmp expect actual
+'
+
+test_expect_success 'normal stream, exit code 1' '
+       test_when_finished "rm trace.normal actual expect" &&
+       test_must_fail env GIT_TR2="$(pwd)/trace.normal" test-tool trace2 002exit 1 &&
+       perl "$TEST_DIRECTORY/t0210/scrub_normal.perl" <trace.normal >actual &&
+       cat >expect <<-EOF &&
+               version $V
+               start _EXE_ trace2 002exit 1
+               cmd_name trace2 (trace2)
+               exit elapsed:_TIME_ code:1
+               atexit elapsed:_TIME_ code:1
+       EOF
+       test_cmp expect actual
+'
+
+# Verb 003error
+#
+# To the above, add multiple 'error <msg>' events
+
+test_expect_success 'normal stream, error event' '
+       test_when_finished "rm trace.normal actual expect" &&
+       GIT_TR2="$(pwd)/trace.normal" test-tool trace2 003error "hello world" "this is a test" &&
+       perl "$TEST_DIRECTORY/t0210/scrub_normal.perl" <trace.normal >actual &&
+       cat >expect <<-EOF &&
+               version $V
+               start _EXE_ trace2 003error '\''hello world'\'' '\''this is a test'\''
+               cmd_name trace2 (trace2)
+               error hello world
+               error this is a test
+               exit elapsed:_TIME_ code:0
+               atexit elapsed:_TIME_ code:0
+       EOF
+       test_cmp expect actual
+'
+
+test_done
diff --git a/t/t0210/scrub_normal.perl b/t/t0210/scrub_normal.perl
new file mode 100644 (file)
index 0000000..c65d1a8
--- /dev/null
@@ -0,0 +1,48 @@
+#!/usr/bin/perl
+#
+# Scrub the variable fields from the normal trace2 output to
+# make testing easier.
+
+use strict;
+use warnings;
+
+my $float = '[0-9]*\.[0-9]+([eE][-+]?[0-9]+)?';
+
+# This code assumes that the trace2 data was written with bare
+# turned on (which omits the "<clock> <file>:<line>" prefix.
+
+while (<>) {
+    # Various messages include an elapsed time in the middle
+    # of the message.  Replace the time with a placeholder to
+    # simplify our HEREDOC in the test script.
+    s/elapsed:$float/elapsed:_TIME_/g;
+
+    my $line = $_;
+
+    # we expect:
+    #    start <argv0> [<argv1> [<argv2> [...]]]
+    #
+    # where argv0 might be a relative or absolute path, with
+    # or without quotes, and platform dependent.  Replace argv0
+    # with a token for HEREDOC matching in the test script.
+
+    if ($line =~ m/^start/) {
+       $line =~ /^start\s+(.*)/;
+       my $argv = $1;
+       $argv =~ m/(\'[^\']*\'|[^ ]+)\s+(.*)/;
+       my $argv_0 = $1;
+       my $argv_rest = $2;
+
+       print "start _EXE_ $argv_rest\n";
+    }
+    elsif ($line =~ m/^cmd_path/) {
+       # Likewise, the 'cmd_path' message breaks out argv[0].
+       #
+       # This line is only emitted when RUNTIME_PREFIX is defined,
+       # so just omit it for testing purposes.
+       # print "cmd_path _EXE_\n";
+    }
+    else {
+       print "$line";
+    }
+}
diff --git a/t/t0211-trace2-perf.sh b/t/t0211-trace2-perf.sh
new file mode 100755 (executable)
index 0000000..953e2f7
--- /dev/null
@@ -0,0 +1,153 @@
+#!/bin/sh
+
+test_description='test trace2 facility (perf target)'
+. ./test-lib.sh
+
+# Add t/helper directory to PATH so that we can use a relative
+# path to run nested instances of test-tool.exe (see 004child).
+# This helps with HEREDOC comparisons later.
+TTDIR="$GIT_BUILD_DIR/t/helper/" && export TTDIR
+PATH="$TTDIR:$PATH" && export PATH
+
+# Warning: use of 'test_cmp' may run test-tool.exe and/or git.exe
+# Warning: to do the actual diff/comparison, so the HEREDOCs here
+# Warning: only cover our actual calls to test-tool and/or git.
+# Warning: So you may see extra lines in artifact files when
+# Warning: interactively debugging.
+
+# Turn off any inherited trace2 settings for this test.
+unset GIT_TR2 GIT_TR2_PERF GIT_TR2_EVENT
+unset GIT_TR2_PERF_BRIEF
+unset GIT_TR2_CONFIG_PARAMS
+
+V=$(git version | sed -e 's/^git version //') && export V
+
+# There are multiple trace2 targets: normal, perf, and event.
+# Trace2 events will/can be written to each active target (subject
+# to whatever filtering that target decides to do).
+# Test each target independently.
+#
+# Defer setting GIT_TR2_PERF until the actual command we want to
+# test because hidden git and test-tool commands in the test
+# harness can contaminate our output.
+
+# Enable "brief" feature which turns off the prefix:
+#     "<clock> <file>:<line> | <nr_parents> | "
+GIT_TR2_PERF_BRIEF=1 && export GIT_TR2_PERF_BRIEF
+
+# Repeat some of the t0210 tests using the perf target stream instead of
+# the normal stream.
+#
+# Tokens here of the form _FIELD_ have been replaced in the observed output.
+
+# Verb 001return
+#
+# Implicit return from cmd_<verb> function propagates <code>.
+
+test_expect_success 'perf stream, return code 0' '
+       test_when_finished "rm trace.perf actual expect" &&
+       GIT_TR2_PERF="$(pwd)/trace.perf" test-tool trace2 001return 0 &&
+       perl "$TEST_DIRECTORY/t0211/scrub_perf.perl" <trace.perf >actual &&
+       cat >expect <<-EOF &&
+               d0|main|version|||||$V
+               d0|main|start|||||_EXE_ trace2 001return 0
+               d0|main|cmd_name|||||trace2 (trace2)
+               d0|main|exit||_T_ABS_|||code:0
+               d0|main|atexit||_T_ABS_|||code:0
+       EOF
+       test_cmp expect actual
+'
+
+test_expect_success 'perf stream, return code 1' '
+       test_when_finished "rm trace.perf actual expect" &&
+       test_must_fail env GIT_TR2_PERF="$(pwd)/trace.perf" test-tool trace2 001return 1 &&
+       perl "$TEST_DIRECTORY/t0211/scrub_perf.perl" <trace.perf >actual &&
+       cat >expect <<-EOF &&
+               d0|main|version|||||$V
+               d0|main|start|||||_EXE_ trace2 001return 1
+               d0|main|cmd_name|||||trace2 (trace2)
+               d0|main|exit||_T_ABS_|||code:1
+               d0|main|atexit||_T_ABS_|||code:1
+       EOF
+       test_cmp expect actual
+'
+
+# Verb 003error
+#
+# To the above, add multiple 'error <msg>' events
+
+test_expect_success 'perf stream, error event' '
+       test_when_finished "rm trace.perf actual expect" &&
+       GIT_TR2_PERF="$(pwd)/trace.perf" test-tool trace2 003error "hello world" "this is a test" &&
+       perl "$TEST_DIRECTORY/t0211/scrub_perf.perl" <trace.perf >actual &&
+       cat >expect <<-EOF &&
+               d0|main|version|||||$V
+               d0|main|start|||||_EXE_ trace2 003error '\''hello world'\'' '\''this is a test'\''
+               d0|main|cmd_name|||||trace2 (trace2)
+               d0|main|error|||||hello world
+               d0|main|error|||||this is a test
+               d0|main|exit||_T_ABS_|||code:0
+               d0|main|atexit||_T_ABS_|||code:0
+       EOF
+       test_cmp expect actual
+'
+
+# Verb 004child
+#
+# Test nested spawning of child processes.
+#
+# Conceptually, this looks like:
+#    P1: TT trace2 004child
+#    P2: |--- TT trace2 004child
+#    P3:      |--- TT trace2 001return 0
+#
+# Which should generate events:
+#    P1: version
+#    P1: start
+#    P1: cmd_name
+#    P1: child_start
+#        P2: version
+#        P2: start
+#        P2: cmd_name
+#        P2: child_start
+#            P3: version
+#            P3: start
+#            P3: cmd_name
+#            P3: exit
+#            P3: atexit
+#        P2: child_exit
+#        P2: exit
+#        P2: atexit
+#    P1: child_exit
+#    P1: exit
+#    P1: atexit
+
+test_expect_success 'perf stream, child processes' '
+       test_when_finished "rm trace.perf actual expect" &&
+       GIT_TR2_PERF="$(pwd)/trace.perf" test-tool trace2 004child test-tool trace2 004child test-tool trace2 001return 0 &&
+       perl "$TEST_DIRECTORY/t0211/scrub_perf.perl" <trace.perf >actual &&
+       cat >expect <<-EOF &&
+               d0|main|version|||||$V
+               d0|main|start|||||_EXE_ trace2 004child test-tool trace2 004child test-tool trace2 001return 0
+               d0|main|cmd_name|||||trace2 (trace2)
+               d0|main|child_start||_T_ABS_|||[ch0] class:? argv: test-tool trace2 004child test-tool trace2 001return 0
+               d1|main|version|||||$V
+               d1|main|start|||||_EXE_ trace2 004child test-tool trace2 001return 0
+               d1|main|cmd_name|||||trace2 (trace2/trace2)
+               d1|main|child_start||_T_ABS_|||[ch0] class:? argv: test-tool trace2 001return 0
+               d2|main|version|||||$V
+               d2|main|start|||||_EXE_ trace2 001return 0
+               d2|main|cmd_name|||||trace2 (trace2/trace2/trace2)
+               d2|main|exit||_T_ABS_|||code:0
+               d2|main|atexit||_T_ABS_|||code:0
+               d1|main|child_exit||_T_ABS_|_T_REL_||[ch0] pid:_PID_ code:0
+               d1|main|exit||_T_ABS_|||code:0
+               d1|main|atexit||_T_ABS_|||code:0
+               d0|main|child_exit||_T_ABS_|_T_REL_||[ch0] pid:_PID_ code:0
+               d0|main|exit||_T_ABS_|||code:0
+               d0|main|atexit||_T_ABS_|||code:0
+       EOF
+       test_cmp expect actual
+'
+
+test_done
diff --git a/t/t0211/scrub_perf.perl b/t/t0211/scrub_perf.perl
new file mode 100644 (file)
index 0000000..351af78
--- /dev/null
@@ -0,0 +1,76 @@
+#!/usr/bin/perl
+#
+# Scrub the variable fields from the perf trace2 output to
+# make testing easier.
+
+use strict;
+use warnings;
+
+my $qpath = '\'[^\']*\'|[^ ]*';
+
+my $col_depth=0;
+my $col_thread=1;
+my $col_event=2;
+my $col_repo=3;
+my $col_t_abs=4;
+my $col_t_rel=5;
+my $col_category=6;
+my $col_rest=7;
+
+# This code assumes that the trace2 data was written with bare
+# turned on (which omits the "<clock> <file>:<line> | <parents>"
+# prefix.
+
+while (<>) {
+    my @tokens = split /\|/;
+
+    foreach my $col (@tokens) { $col =~ s/^\s+|\s+$//g; }
+
+    if ($tokens[$col_event] =~ m/^start/) {
+       # The 'start' message lists the contents of argv in $col_rest.
+       # On some platforms (Windows), argv[0] is *sometimes* a canonical
+       # absolute path to the EXE rather than the value passed in the
+       # shell script.  Replace it with a placeholder to simplify our
+       # HEREDOC in the test script.
+       my $argv0;
+       my $argvRest;
+       $tokens[$col_rest] =~ s/^($qpath)\W*(.*)/_EXE_ $2/;
+    }
+    elsif ($tokens[$col_event] =~ m/cmd_path/) {
+       # Likewise, the 'cmd_path' message breaks out argv[0].
+       #
+       # This line is only emitted when RUNTIME_PREFIX is defined,
+       # so just omit it for testing purposes.
+       # $tokens[$col_rest] = "_EXE_";
+       goto SKIP_LINE;
+    }
+    elsif ($tokens[$col_event] =~ m/child_exit/) {
+       $tokens[$col_rest] =~ s/ pid:\d* / pid:_PID_ /;
+    }
+    elsif ($tokens[$col_event] =~ m/data/) {
+       if ($tokens[$col_category] =~ m/process/) {
+           # 'data' and 'data_json' events containing 'process'
+           # category data are assumed to be platform-specific
+           # and highly variable.  Just omit them.
+           goto SKIP_LINE;
+       }
+    }
+
+    # t_abs and t_rel are either blank or a float.  Replace the float
+    # with a constant for matching the HEREDOC in the test script.
+    if ($tokens[$col_t_abs] =~ m/\d/) {
+       $tokens[$col_t_abs] = "_T_ABS_";
+    }
+    if ($tokens[$col_t_rel] =~ m/\d/) {
+       $tokens[$col_t_rel] = "_T_REL_";
+    }
+
+    my $out;
+
+    $out = join('|', @tokens);
+    print "$out\n";
+
+  SKIP_LINE:
+}
+
+
diff --git a/t/t0212-trace2-event.sh b/t/t0212-trace2-event.sh
new file mode 100755 (executable)
index 0000000..028b6c5
--- /dev/null
@@ -0,0 +1,236 @@
+#!/bin/sh
+
+test_description='test trace2 facility'
+. ./test-lib.sh
+
+perl -MJSON::PP -e 0 >/dev/null 2>&1 && test_set_prereq JSON_PP
+
+# Add t/helper directory to PATH so that we can use a relative
+# path to run nested instances of test-tool.exe (see 004child).
+# This helps with HEREDOC comparisons later.
+TTDIR="$GIT_BUILD_DIR/t/helper/" && export TTDIR
+PATH="$TTDIR:$PATH" && export PATH
+
+# Warning: use of 'test_cmp' may run test-tool.exe and/or git.exe
+# Warning: to do the actual diff/comparison, so the HEREDOCs here
+# Warning: only cover our actual calls to test-tool and/or git.
+# Warning: So you may see extra lines in artifact files when
+# Warning: interactively debugging.
+
+# Turn off any inherited trace2 settings for this test.
+unset GIT_TR2 GIT_TR2_PERF GIT_TR2_EVENT
+unset GIT_TR2_BARE
+unset GIT_TR2_CONFIG_PARAMS
+
+V=$(git version | sed -e 's/^git version //') && export V
+
+# There are multiple trace2 targets: normal, perf, and event.
+# Trace2 events will/can be written to each active target (subject
+# to whatever filtering that target decides to do).
+# Test each target independently.
+#
+# Defer setting GIT_TR2_PERF until the actual command we want to
+# test because hidden git and test-tool commands in the test
+# harness can contaminate our output.
+
+# We don't bother repeating the 001return and 002exit tests, since they
+# have coverage in the normal and perf targets.
+
+# Verb 003error
+#
+# To the above, add multiple 'error <msg>' events
+
+test_expect_success JSON_PP 'event stream, error event' '
+       test_when_finished "rm trace.event actual expect" &&
+       GIT_TR2_EVENT="$(pwd)/trace.event" test-tool trace2 003error "hello world" "this is a test" &&
+       perl "$TEST_DIRECTORY/t0212/parse_events.perl" <trace.event >actual &&
+       sed -e "s/^|//" >expect <<-EOF &&
+       |VAR1 = {
+       |  "_SID0_":{
+       |    "argv":[
+       |      "_EXE_",
+       |      "trace2",
+       |      "003error",
+       |      "hello world",
+       |      "this is a test"
+       |    ],
+       |    "errors":[
+       |      "%s",
+       |      "%s"
+       |    ],
+       |    "exit_code":0,
+       |    "hierarchy":"trace2",
+       |    "name":"trace2",
+       |    "version":"$V"
+       |  }
+       |};
+       EOF
+       test_cmp expect actual
+'
+
+# Verb 004child
+#
+# Test nested spawning of child processes.
+#
+# Conceptually, this looks like:
+#    P1: TT trace2 004child
+#    P2: |--- TT trace2 004child
+#    P3:      |--- TT trace2 001return 0
+
+test_expect_success JSON_PP 'event stream, return code 0' '
+       test_when_finished "rm trace.event actual expect" &&
+       GIT_TR2_EVENT="$(pwd)/trace.event" test-tool trace2 004child test-tool trace2 004child test-tool trace2 001return 0 &&
+       perl "$TEST_DIRECTORY/t0212/parse_events.perl" <trace.event >actual &&
+       sed -e "s/^|//" >expect <<-EOF &&
+       |VAR1 = {
+       |  "_SID0_":{
+       |    "argv":[
+       |      "_EXE_",
+       |      "trace2",
+       |      "004child",
+       |      "test-tool",
+       |      "trace2",
+       |      "004child",
+       |      "test-tool",
+       |      "trace2",
+       |      "001return",
+       |      "0"
+       |    ],
+       |    "child":{
+       |      "0":{
+       |        "child_argv":[
+       |          "_EXE_",
+       |          "trace2",
+       |          "004child",
+       |          "test-tool",
+       |          "trace2",
+       |          "001return",
+       |          "0"
+       |        ],
+       |        "child_class":"?",
+       |        "child_code":0,
+       |        "use_shell":0
+       |      }
+       |    },
+       |    "exit_code":0,
+       |    "hierarchy":"trace2",
+       |    "name":"trace2",
+       |    "version":"$V"
+       |  },
+       |  "_SID0_/_SID1_":{
+       |    "argv":[
+       |      "_EXE_",
+       |      "trace2",
+       |      "004child",
+       |      "test-tool",
+       |      "trace2",
+       |      "001return",
+       |      "0"
+       |    ],
+       |    "child":{
+       |      "0":{
+       |        "child_argv":[
+       |          "_EXE_",
+       |          "trace2",
+       |          "001return",
+       |          "0"
+       |        ],
+       |        "child_class":"?",
+       |        "child_code":0,
+       |        "use_shell":0
+       |      }
+       |    },
+       |    "exit_code":0,
+       |    "hierarchy":"trace2/trace2",
+       |    "name":"trace2",
+       |    "version":"$V"
+       |  },
+       |  "_SID0_/_SID1_/_SID2_":{
+       |    "argv":[
+       |      "_EXE_",
+       |      "trace2",
+       |      "001return",
+       |      "0"
+       |    ],
+       |    "exit_code":0,
+       |    "hierarchy":"trace2/trace2/trace2",
+       |    "name":"trace2",
+       |    "version":"$V"
+       |  }
+       |};
+       EOF
+       test_cmp expect actual
+'
+
+# Test listing of all "interesting" config settings.
+
+test_expect_success JSON_PP 'event stream, list config' '
+       test_when_finished "rm trace.event actual expect" &&
+       git config --local t0212.abc 1 &&
+       git config --local t0212.def "hello world" &&
+       GIT_TR2_EVENT="$(pwd)/trace.event" GIT_TR2_CONFIG_PARAMS="t0212.*" test-tool trace2 001return 0 &&
+       perl "$TEST_DIRECTORY/t0212/parse_events.perl" <trace.event >actual &&
+       sed -e "s/^|//" >expect <<-EOF &&
+       |VAR1 = {
+       |  "_SID0_":{
+       |    "argv":[
+       |      "_EXE_",
+       |      "trace2",
+       |      "001return",
+       |      "0"
+       |    ],
+       |    "exit_code":0,
+       |    "hierarchy":"trace2",
+       |    "name":"trace2",
+       |    "params":[
+       |      {
+       |        "param":"t0212.abc",
+       |        "value":"1"
+       |      },
+       |      {
+       |        "param":"t0212.def",
+       |        "value":"hello world"
+       |      }
+       |    ],
+       |    "version":"$V"
+       |  }
+       |};
+       EOF
+       test_cmp expect actual
+'
+
+test_expect_success JSON_PP 'basic trace2_data' '
+       test_when_finished "rm trace.event actual expect" &&
+       GIT_TR2_EVENT="$(pwd)/trace.event" test-tool trace2 006data test_category k1 v1 test_category k2 v2 &&
+       perl "$TEST_DIRECTORY/t0212/parse_events.perl" <trace.event >actual &&
+       sed -e "s/^|//" >expect <<-EOF &&
+       |VAR1 = {
+       |  "_SID0_":{
+       |    "argv":[
+       |      "_EXE_",
+       |      "trace2",
+       |      "006data",
+       |      "test_category",
+       |      "k1",
+       |      "v1",
+       |      "test_category",
+       |      "k2",
+       |      "v2"
+       |    ],
+       |    "data":{
+       |      "test_category":{
+       |        "k1":"v1",
+       |        "k2":"v2"
+       |      }
+       |    },
+       |    "exit_code":0,
+       |    "hierarchy":"trace2",
+       |    "name":"trace2",
+       |    "version":"$V"
+       |  }
+       |};
+       EOF
+       test_cmp expect actual
+'
+
+test_done
diff --git a/t/t0212/parse_events.perl b/t/t0212/parse_events.perl
new file mode 100644 (file)
index 0000000..a2776ba
--- /dev/null
@@ -0,0 +1,251 @@
+#!/usr/bin/perl
+#
+# Parse event stream and convert individual events into a summary
+# record for the process.
+#
+# Git.exe generates one or more "event" records for each API method,
+# such as "start <argv>" and "exit <code>", during the life of the git
+# process.  Additionally, the input may contain interleaved events
+# from multiple concurrent git processes and/or multiple threads from
+# within a git process.
+#
+# Accumulate events for each process (based on its unique SID) in a
+# dictionary and emit process summary records.
+#
+# Convert some of the variable fields (such as elapsed time) into
+# placeholders (or omit them) to make HEREDOC comparisons easier in
+# the test scripts.
+#
+# We may also omit fields not (currently) useful for testing purposes.
+
+use strict;
+use warnings;
+use JSON::PP;
+use Data::Dumper;
+use Getopt::Long;
+
+# The version of the trace2 event target format that we understand.
+# This is reported in the 'version' event in the 'evt' field.
+# It comes from the GIT_TR2_EVENT_VERSION macro in trace2/tr2_tgt_event.c
+my $evt_version = '1';
+
+my $show_children = 1;
+my $show_exec     = 1;
+my $show_threads  = 1;
+
+# A hack to generate test HEREDOC data for pasting into the test script.
+# Usage:
+#    cd "t/trash directory.t0212-trace2-event"
+#    $TT trace ... >trace.event
+#    VV=$(../../git.exe version | sed -e 's/^git version //')
+#    perl ../t0212/parse_events.perl --HEREDOC --VERSION=$VV <trace.event >heredoc
+# Then paste heredoc into your new test.
+
+my $gen_heredoc = 0;
+my $gen_version = '';
+
+GetOptions("children!" => \$show_children,
+          "exec!"     => \$show_exec,
+          "threads!"  => \$show_threads,
+          "HEREDOC!"  => \$gen_heredoc,
+          "VERSION=s" => \$gen_version    )
+    or die("Error in command line arguments\n");
+
+
+# SIDs contains timestamps and PIDs of the process and its parents.
+# This makes it difficult to match up in a HEREDOC in the test script.
+# Build a map from actual SIDs to predictable constant values and yet
+# keep the parent/child relationships.  For example:
+# {..., "sid":"1539706952458276-8652", ...}
+# {..., "sid":"1539706952458276-8652/1539706952649493-15452", ...}
+# becomes:
+# {..., "sid":"_SID1_", ...}
+# {..., "sid":"_SID1_/_SID2_", ...}
+my $sid_map;
+my $sid_count = 0;
+
+my $processes;
+
+while (<>) {
+    my $line = decode_json( $_ );
+
+    my $sid = "";
+    my $sid_sep = "";
+
+    my $raw_sid = $line->{'sid'};
+    my @raw_sid_parts = split /\//, $raw_sid;
+    foreach my $raw_sid_k (@raw_sid_parts) {
+       if (!exists $sid_map->{$raw_sid_k}) {
+           $sid_map->{$raw_sid_k} = '_SID' . $sid_count . '_';
+           $sid_count++;
+       }
+       $sid = $sid . $sid_sep . $sid_map->{$raw_sid_k};
+       $sid_sep = '/';
+    }
+    
+    my $event = $line->{'event'};
+
+    if ($event eq 'version') {
+       $processes->{$sid}->{'version'} = $line->{'exe'};
+       if ($gen_heredoc == 1 && $gen_version eq $line->{'exe'}) {
+           # If we are generating data FOR the test script, replace
+           # the reported git.exe version with a reference to an
+           # environment variable.  When our output is pasted into
+           # the test script, it will then be expanded in future
+           # test runs to the THEN current version of git.exe.
+           # We assume that the test script uses env var $V.
+           $processes->{$sid}->{'version'} = "\$V";
+       }
+    }
+
+    elsif ($event eq 'start') {
+       $processes->{$sid}->{'argv'} = $line->{'argv'};
+       $processes->{$sid}->{'argv'}[0] = "_EXE_";
+    }
+
+    elsif ($event eq 'exit') {
+       $processes->{$sid}->{'exit_code'} = $line->{'code'};
+    }
+
+    elsif ($event eq 'atexit') {
+       $processes->{$sid}->{'exit_code'} = $line->{'code'};
+    }
+
+    elsif ($event eq 'error') {
+       # For HEREDOC purposes, use the error message format string if
+       # available, rather than the formatted message (which probably
+       # has an absolute pathname).
+       if (exists $line->{'fmt'}) {
+           push( @{$processes->{$sid}->{'errors'}}, $line->{'fmt'} );
+       }
+       elsif (exists $line->{'msg'}) {
+           push( @{$processes->{$sid}->{'errors'}}, $line->{'msg'} );
+       }
+    }
+
+    elsif ($event eq 'cmd_path') {
+       ## $processes->{$sid}->{'path'} = $line->{'path'};
+       #
+       # Like in the 'start' event, we need to replace the value of
+       # argv[0] with a token for HEREDOC purposes.  However, the
+       # event is only emitted when RUNTIME_PREFIX is defined, so
+       # just omit it for testing purposes.
+       # $processes->{$sid}->{'path'} = "_EXE_";
+    }
+    
+    elsif ($event eq 'cmd_name') {
+       $processes->{$sid}->{'name'} = $line->{'name'};
+       $processes->{$sid}->{'hierarchy'} = $line->{'hierarchy'};
+    }
+
+    elsif ($event eq 'alias') {
+       $processes->{$sid}->{'alias'}->{'key'} = $line->{'alias'};
+       $processes->{$sid}->{'alias'}->{'argv'} = $line->{'argv'};
+    }
+
+    elsif ($event eq 'def_param') {
+       my $kv;
+       $kv->{'param'} = $line->{'param'};
+       $kv->{'value'} = $line->{'value'};
+       push( @{$processes->{$sid}->{'params'}}, $kv );
+    }
+
+    elsif ($event eq 'child_start') {
+       if ($show_children == 1) {
+           $processes->{$sid}->{'child'}->{$line->{'child_id'}}->{'child_class'} = $line->{'child_class'};
+           $processes->{$sid}->{'child'}->{$line->{'child_id'}}->{'child_argv'} = $line->{'argv'};
+           $processes->{$sid}->{'child'}->{$line->{'child_id'}}->{'child_argv'}[0] = "_EXE_";
+           $processes->{$sid}->{'child'}->{$line->{'child_id'}}->{'use_shell'} = $line->{'use_shell'} ? 1 : 0;
+       }
+    }
+
+    elsif ($event eq 'child_exit') {
+       if ($show_children == 1) {
+           $processes->{$sid}->{'child'}->{$line->{'child_id'}}->{'child_code'} = $line->{'code'};
+       }
+    }
+
+    # TODO decide what information we want to test from thread events.
+
+    elsif ($event eq 'thread_start') {
+       if ($show_threads == 1) {
+       }
+    }
+
+    elsif ($event eq 'thread_exit') {
+       if ($show_threads == 1) {
+       }
+    }
+
+    # TODO decide what information we want to test from exec events.
+
+    elsif ($event eq 'exec') {
+       if ($show_exec == 1) {
+       }
+    }
+
+    elsif ($event eq 'exec_result') {
+       if ($show_exec == 1) {
+       }
+    }
+
+    elsif ($event eq 'def_param') {
+       # Accumulate parameter key/value pairs by key rather than in an array
+       # so that we get overwrite (last one wins) effects.
+       $processes->{$sid}->{'params'}->{$line->{'param'}} = $line->{'value'};
+    }
+
+    elsif ($event eq 'def_repo') {
+       # $processes->{$sid}->{'repos'}->{$line->{'repo'}} = $line->{'worktree'};
+       $processes->{$sid}->{'repos'}->{$line->{'repo'}} = "_WORKTREE_";
+    }
+
+    # A series of potentially nested and threaded region and data events
+    # is fundamentally incompatibile with the type of summary record we
+    # are building in this script.  Since they are intended for
+    # perf-trace-like analysis rather than a result summary, we ignore
+    # most of them here.
+
+    # elsif ($event eq 'region_enter') {
+    # }
+    # elsif ($event eq 'region_leave') {
+    # }
+
+    elsif ($event eq 'data') {
+       my $cat = $line->{'category'};
+       if ($cat eq 'test_category') {
+           
+           my $key = $line->{'key'};
+           my $value = $line->{'value'};
+           $processes->{$sid}->{'data'}->{$cat}->{$key} = $value;
+       }
+    }
+
+    # This trace2 target does not emit 'printf' events.
+    #
+    # elsif ($event eq 'printf') {
+    # }
+}
+
+# Dump the resulting hash into something that we can compare against
+# in the test script.  These options make Dumper output look a little
+# bit like JSON.  Also convert variable references of the form "$VAR*"
+# so that the matching HEREDOC doesn't need to escape it.
+
+$Data::Dumper::Sortkeys = 1;
+$Data::Dumper::Indent = 1;
+$Data::Dumper::Purity = 1;
+$Data::Dumper::Pair = ':';
+
+my $out = Dumper($processes);
+$out =~ s/'/"/g;
+$out =~ s/\$VAR/VAR/g;
+
+# Finally, if we're running this script to generate (manually confirmed)
+# data to add to the test script, guard the indentation.
+
+if ($gen_heredoc == 1) {
+    $out =~ s/^/\t\|/gms;
+}
+
+print $out;
diff --git a/trace2.c b/trace2.c
new file mode 100644 (file)
index 0000000..ccccd4e
--- /dev/null
+++ b/trace2.c
@@ -0,0 +1,761 @@
+#include "cache.h"
+#include "config.h"
+#include "json-writer.h"
+#include "quote.h"
+#include "run-command.h"
+#include "sigchain.h"
+#include "thread-utils.h"
+#include "version.h"
+#include "trace2/tr2_cfg.h"
+#include "trace2/tr2_cmd_name.h"
+#include "trace2/tr2_dst.h"
+#include "trace2/tr2_sid.h"
+#include "trace2/tr2_tgt.h"
+#include "trace2/tr2_tls.h"
+
+static int trace2_enabled;
+
+static int tr2_next_child_id; /* modify under lock */
+static int tr2_next_exec_id; /* modify under lock */
+static int tr2_next_repo_id = 1; /* modify under lock. zero is reserved */
+
+/*
+ * A table of the builtin TRACE2 targets.  Each of these may be independently
+ * enabled or disabled.  Each TRACE2 API method will try to write an event to
+ * *each* of the enabled targets.
+ */
+/* clang-format off */
+static struct tr2_tgt *tr2_tgt_builtins[] =
+{
+       &tr2_tgt_normal,
+       &tr2_tgt_perf,
+       &tr2_tgt_event,
+       NULL
+};
+/* clang-format on */
+
+/* clang-format off */
+#define for_each_builtin(j, tgt_j)                     \
+       for (j = 0, tgt_j = tr2_tgt_builtins[j];        \
+            tgt_j;                                     \
+            j++, tgt_j = tr2_tgt_builtins[j])
+/* clang-format on */
+
+/* clang-format off */
+#define for_each_wanted_builtin(j, tgt_j)            \
+       for_each_builtin(j, tgt_j)                   \
+               if (tr2_dst_trace_want(tgt_j->pdst))
+/* clang-format on */
+
+/*
+ * Force (rather than lazily) initialize any of the requested
+ * builtin TRACE2 targets at startup (and before we've seen an
+ * actual TRACE2 event call) so we can see if we need to setup
+ * the TR2 and TLS machinery.
+ *
+ * Return the number of builtin targets enabled.
+ */
+static int tr2_tgt_want_builtins(void)
+{
+       struct tr2_tgt *tgt_j;
+       int j;
+       int sum = 0;
+
+       for_each_builtin (j, tgt_j)
+               if (tgt_j->pfn_init())
+                       sum++;
+
+       return sum;
+}
+
+/*
+ * Properly terminate each builtin target.  Give each target
+ * a chance to write a summary event and/or flush if necessary
+ * and then close the fd.
+ */
+static void tr2_tgt_disable_builtins(void)
+{
+       struct tr2_tgt *tgt_j;
+       int j;
+
+       for_each_builtin (j, tgt_j)
+               tgt_j->pfn_term();
+}
+
+static int tr2main_exit_code;
+
+/*
+ * Our atexit routine should run after everything has finished.
+ *
+ * Note that events generated here might not actually appear if
+ * we are writing to fd 1 or 2 and our atexit routine runs after
+ * the pager's atexit routine (since it closes them to shutdown
+ * the pipes).
+ */
+static void tr2main_atexit_handler(void)
+{
+       struct tr2_tgt *tgt_j;
+       int j;
+       uint64_t us_now;
+       uint64_t us_elapsed_absolute;
+
+       us_now = getnanotime() / 1000;
+       us_elapsed_absolute = tr2tls_absolute_elapsed(us_now);
+
+       /*
+        * Clear any unbalanced regions so that our atexit message
+        * does not appear nested.  This improves the appearance of
+        * the trace output if someone calls die(), for example.
+        */
+       tr2tls_pop_unwind_self();
+
+       for_each_wanted_builtin (j, tgt_j)
+               if (tgt_j->pfn_atexit)
+                       tgt_j->pfn_atexit(us_elapsed_absolute,
+                                         tr2main_exit_code);
+
+       tr2_tgt_disable_builtins();
+
+       tr2tls_release();
+       tr2_sid_release();
+       tr2_cmd_name_release();
+       tr2_cfg_free_patterns();
+
+       trace2_enabled = 0;
+}
+
+static void tr2main_signal_handler(int signo)
+{
+       struct tr2_tgt *tgt_j;
+       int j;
+       uint64_t us_now;
+       uint64_t us_elapsed_absolute;
+
+       us_now = getnanotime() / 1000;
+       us_elapsed_absolute = tr2tls_absolute_elapsed(us_now);
+
+       for_each_wanted_builtin (j, tgt_j)
+               if (tgt_j->pfn_signal)
+                       tgt_j->pfn_signal(us_elapsed_absolute, signo);
+
+       sigchain_pop(signo);
+       raise(signo);
+}
+
+void trace2_initialize_fl(const char *file, int line)
+{
+       struct tr2_tgt *tgt_j;
+       int j;
+
+       if (trace2_enabled)
+               return;
+
+       if (!tr2_tgt_want_builtins())
+               return;
+       trace2_enabled = 1;
+
+       tr2_sid_get();
+
+       atexit(tr2main_atexit_handler);
+       sigchain_push(SIGPIPE, tr2main_signal_handler);
+       tr2tls_init();
+
+       /*
+        * Emit 'version' message on each active builtin target.
+        */
+       for_each_wanted_builtin (j, tgt_j)
+               if (tgt_j->pfn_version_fl)
+                       tgt_j->pfn_version_fl(file, line);
+}
+
+int trace2_is_enabled(void)
+{
+       return trace2_enabled;
+}
+
+void trace2_cmd_start_fl(const char *file, int line, const char **argv)
+{
+       struct tr2_tgt *tgt_j;
+       int j;
+
+       if (!trace2_enabled)
+               return;
+
+       for_each_wanted_builtin (j, tgt_j)
+               if (tgt_j->pfn_start_fl)
+                       tgt_j->pfn_start_fl(file, line, argv);
+}
+
+int trace2_cmd_exit_fl(const char *file, int line, int code)
+{
+       struct tr2_tgt *tgt_j;
+       int j;
+       uint64_t us_now;
+       uint64_t us_elapsed_absolute;
+
+       code &= 0xff;
+
+       if (!trace2_enabled)
+               return code;
+
+       tr2main_exit_code = code;
+
+       us_now = getnanotime() / 1000;
+       us_elapsed_absolute = tr2tls_absolute_elapsed(us_now);
+
+       for_each_wanted_builtin (j, tgt_j)
+               if (tgt_j->pfn_exit_fl)
+                       tgt_j->pfn_exit_fl(file, line, us_elapsed_absolute,
+                                          code);
+
+       return code;
+}
+
+void trace2_cmd_error_va_fl(const char *file, int line, const char *fmt,
+                           va_list ap)
+{
+       struct tr2_tgt *tgt_j;
+       int j;
+
+       if (!trace2_enabled)
+               return;
+
+       /*
+        * We expect each target function to treat 'ap' as constant
+        * and use va_copy (because an 'ap' can only be walked once).
+        */
+       for_each_wanted_builtin (j, tgt_j)
+               if (tgt_j->pfn_error_va_fl)
+                       tgt_j->pfn_error_va_fl(file, line, fmt, ap);
+}
+
+void trace2_cmd_path_fl(const char *file, int line, const char *pathname)
+{
+       struct tr2_tgt *tgt_j;
+       int j;
+
+       if (!trace2_enabled)
+               return;
+
+       for_each_wanted_builtin (j, tgt_j)
+               if (tgt_j->pfn_command_path_fl)
+                       tgt_j->pfn_command_path_fl(file, line, pathname);
+}
+
+void trace2_cmd_name_fl(const char *file, int line, const char *name)
+{
+       struct tr2_tgt *tgt_j;
+       const char *hierarchy;
+       int j;
+
+       if (!trace2_enabled)
+               return;
+
+       tr2_cmd_name_append_hierarchy(name);
+       hierarchy = tr2_cmd_name_get_hierarchy();
+
+       for_each_wanted_builtin (j, tgt_j)
+               if (tgt_j->pfn_command_name_fl)
+                       tgt_j->pfn_command_name_fl(file, line, name, hierarchy);
+}
+
+void trace2_cmd_mode_fl(const char *file, int line, const char *mode)
+{
+       struct tr2_tgt *tgt_j;
+       int j;
+
+       if (!trace2_enabled)
+               return;
+
+       for_each_wanted_builtin (j, tgt_j)
+               if (tgt_j->pfn_command_mode_fl)
+                       tgt_j->pfn_command_mode_fl(file, line, mode);
+}
+
+void trace2_cmd_alias_fl(const char *file, int line, const char *alias,
+                        const char **argv)
+{
+       struct tr2_tgt *tgt_j;
+       int j;
+
+       if (!trace2_enabled)
+               return;
+
+       for_each_wanted_builtin (j, tgt_j)
+               if (tgt_j->pfn_alias_fl)
+                       tgt_j->pfn_alias_fl(file, line, alias, argv);
+}
+
+void trace2_cmd_list_config_fl(const char *file, int line)
+{
+       if (!trace2_enabled)
+               return;
+
+       tr2_cfg_list_config_fl(file, line);
+}
+
+void trace2_cmd_set_config_fl(const char *file, int line, const char *key,
+                             const char *value)
+{
+       if (!trace2_enabled)
+               return;
+
+       tr2_cfg_set_fl(file, line, key, value);
+}
+
+void trace2_child_start_fl(const char *file, int line,
+                          struct child_process *cmd)
+{
+       struct tr2_tgt *tgt_j;
+       int j;
+       uint64_t us_now;
+       uint64_t us_elapsed_absolute;
+
+       if (!trace2_enabled)
+               return;
+
+       us_now = getnanotime() / 1000;
+       us_elapsed_absolute = tr2tls_absolute_elapsed(us_now);
+
+       cmd->trace2_child_id = tr2tls_locked_increment(&tr2_next_child_id);
+       cmd->trace2_child_us_start = us_now;
+
+       for_each_wanted_builtin (j, tgt_j)
+               if (tgt_j->pfn_child_start_fl)
+                       tgt_j->pfn_child_start_fl(file, line,
+                                                 us_elapsed_absolute, cmd);
+}
+
+void trace2_child_exit_fl(const char *file, int line, struct child_process *cmd,
+                         int child_exit_code)
+{
+       struct tr2_tgt *tgt_j;
+       int j;
+       uint64_t us_now;
+       uint64_t us_elapsed_absolute;
+       uint64_t us_elapsed_child;
+
+       if (!trace2_enabled)
+               return;
+
+       us_now = getnanotime() / 1000;
+       us_elapsed_absolute = tr2tls_absolute_elapsed(us_now);
+
+       if (cmd->trace2_child_us_start)
+               us_elapsed_child = us_now - cmd->trace2_child_us_start;
+       else
+               us_elapsed_child = 0;
+
+       for_each_wanted_builtin (j, tgt_j)
+               if (tgt_j->pfn_child_exit_fl)
+                       tgt_j->pfn_child_exit_fl(file, line,
+                                                us_elapsed_absolute,
+                                                cmd->trace2_child_id, cmd->pid,
+                                                child_exit_code,
+                                                us_elapsed_child);
+}
+
+int trace2_exec_fl(const char *file, int line, const char *exe,
+                  const char **argv)
+{
+       struct tr2_tgt *tgt_j;
+       int j;
+       int exec_id;
+       uint64_t us_now;
+       uint64_t us_elapsed_absolute;
+
+       if (!trace2_enabled)
+               return -1;
+
+       us_now = getnanotime() / 1000;
+       us_elapsed_absolute = tr2tls_absolute_elapsed(us_now);
+
+       exec_id = tr2tls_locked_increment(&tr2_next_exec_id);
+
+       for_each_wanted_builtin (j, tgt_j)
+               if (tgt_j->pfn_exec_fl)
+                       tgt_j->pfn_exec_fl(file, line, us_elapsed_absolute,
+                                          exec_id, exe, argv);
+
+       return exec_id;
+}
+
+void trace2_exec_result_fl(const char *file, int line, int exec_id, int code)
+{
+       struct tr2_tgt *tgt_j;
+       int j;
+       uint64_t us_now;
+       uint64_t us_elapsed_absolute;
+
+       if (!trace2_enabled)
+               return;
+
+       us_now = getnanotime() / 1000;
+       us_elapsed_absolute = tr2tls_absolute_elapsed(us_now);
+
+       for_each_wanted_builtin (j, tgt_j)
+               if (tgt_j->pfn_exec_result_fl)
+                       tgt_j->pfn_exec_result_fl(
+                               file, line, us_elapsed_absolute, exec_id, code);
+}
+
+void trace2_thread_start_fl(const char *file, int line, const char *thread_name)
+{
+       struct tr2_tgt *tgt_j;
+       int j;
+       uint64_t us_now;
+       uint64_t us_elapsed_absolute;
+
+       if (!trace2_enabled)
+               return;
+
+       if (tr2tls_is_main_thread()) {
+               /*
+                * We should only be called from the new thread's thread-proc,
+                * so this is technically a bug.  But in those cases where the
+                * main thread also runs the thread-proc function (or when we
+                * are built with threading disabled), we need to allow it.
+                *
+                * Convert this call to a region-enter so the nesting looks
+                * correct.
+                */
+               trace2_region_enter_printf_fl(file, line, NULL, NULL, NULL,
+                                             "thread-proc on main: %s",
+                                             thread_name);
+               return;
+       }
+
+       us_now = getnanotime() / 1000;
+       us_elapsed_absolute = tr2tls_absolute_elapsed(us_now);
+
+       tr2tls_create_self(thread_name);
+
+       for_each_wanted_builtin (j, tgt_j)
+               if (tgt_j->pfn_thread_start_fl)
+                       tgt_j->pfn_thread_start_fl(file, line,
+                                                  us_elapsed_absolute);
+}
+
+void trace2_thread_exit_fl(const char *file, int line)
+{
+       struct tr2_tgt *tgt_j;
+       int j;
+       uint64_t us_now;
+       uint64_t us_elapsed_absolute;
+       uint64_t us_elapsed_thread;
+
+       if (!trace2_enabled)
+               return;
+
+       if (tr2tls_is_main_thread()) {
+               /*
+                * We should only be called from the exiting thread's
+                * thread-proc, so this is technically a bug.  But in
+                * those cases where the main thread also runs the
+                * thread-proc function (or when we are built with
+                * threading disabled), we need to allow it.
+                *
+                * Convert this call to a region-leave so the nesting
+                * looks correct.
+                */
+               trace2_region_leave_printf_fl(file, line, NULL, NULL, NULL,
+                                             "thread-proc on main");
+               return;
+       }
+
+       us_now = getnanotime() / 1000;
+       us_elapsed_absolute = tr2tls_absolute_elapsed(us_now);
+
+       /*
+        * Clear any unbalanced regions and then get the relative time
+        * for the outer-most region (which we pushed when the thread
+        * started).  This gives us the run time of the thread.
+        */
+       tr2tls_pop_unwind_self();
+       us_elapsed_thread = tr2tls_region_elasped_self(us_now);
+
+       for_each_wanted_builtin (j, tgt_j)
+               if (tgt_j->pfn_thread_exit_fl)
+                       tgt_j->pfn_thread_exit_fl(file, line,
+                                                 us_elapsed_absolute,
+                                                 us_elapsed_thread);
+
+       tr2tls_unset_self();
+}
+
+void trace2_def_param_fl(const char *file, int line, const char *param,
+                        const char *value)
+{
+       struct tr2_tgt *tgt_j;
+       int j;
+
+       if (!trace2_enabled)
+               return;
+
+       for_each_wanted_builtin (j, tgt_j)
+               if (tgt_j->pfn_param_fl)
+                       tgt_j->pfn_param_fl(file, line, param, value);
+}
+
+void trace2_def_repo_fl(const char *file, int line, struct repository *repo)
+{
+       struct tr2_tgt *tgt_j;
+       int j;
+
+       if (!trace2_enabled)
+               return;
+
+       if (repo->trace2_repo_id)
+               return;
+
+       repo->trace2_repo_id = tr2tls_locked_increment(&tr2_next_repo_id);
+
+       for_each_wanted_builtin (j, tgt_j)
+               if (tgt_j->pfn_repo_fl)
+                       tgt_j->pfn_repo_fl(file, line, repo);
+}
+
+void trace2_region_enter_printf_va_fl(const char *file, int line,
+                                     const char *category, const char *label,
+                                     const struct repository *repo,
+                                     const char *fmt, va_list ap)
+{
+       struct tr2_tgt *tgt_j;
+       int j;
+       uint64_t us_now;
+       uint64_t us_elapsed_absolute;
+
+       if (!trace2_enabled)
+               return;
+
+       us_now = getnanotime() / 1000;
+       us_elapsed_absolute = tr2tls_absolute_elapsed(us_now);
+
+       /*
+        * Print the region-enter message at the current nesting
+        * (indentation) level and then push a new level.
+        *
+        * We expect each target function to treat 'ap' as constant
+        * and use va_copy.
+        */
+       for_each_wanted_builtin (j, tgt_j)
+               if (tgt_j->pfn_region_enter_printf_va_fl)
+                       tgt_j->pfn_region_enter_printf_va_fl(
+                               file, line, us_elapsed_absolute, category,
+                               label, repo, fmt, ap);
+
+       tr2tls_push_self(us_now);
+}
+
+void trace2_region_enter_fl(const char *file, int line, const char *category,
+                           const char *label, const struct repository *repo)
+{
+       trace2_region_enter_printf_va_fl(file, line, category, label, repo,
+                                        NULL, NULL);
+}
+
+void trace2_region_enter_printf_fl(const char *file, int line,
+                                  const char *category, const char *label,
+                                  const struct repository *repo,
+                                  const char *fmt, ...)
+{
+       va_list ap;
+
+       va_start(ap, fmt);
+       trace2_region_enter_printf_va_fl(file, line, category, label, repo, fmt,
+                                        ap);
+       va_end(ap);
+}
+
+#ifndef HAVE_VARIADIC_MACROS
+void trace2_region_enter_printf(const char *category, const char *label,
+                               const struct repository *repo, const char *fmt,
+                               ...)
+{
+       va_list ap;
+
+       va_start(ap, fmt);
+       trace2_region_enter_printf_va_fl(NULL, 0, category, label, repo, fmt,
+                                        ap);
+       va_end(ap);
+}
+#endif
+
+void trace2_region_leave_printf_va_fl(const char *file, int line,
+                                     const char *category, const char *label,
+                                     const struct repository *repo,
+                                     const char *fmt, va_list ap)
+{
+       struct tr2_tgt *tgt_j;
+       int j;
+       uint64_t us_now;
+       uint64_t us_elapsed_absolute;
+       uint64_t us_elapsed_region;
+
+       if (!trace2_enabled)
+               return;
+
+       us_now = getnanotime() / 1000;
+       us_elapsed_absolute = tr2tls_absolute_elapsed(us_now);
+
+       /*
+        * Get the elapsed time in the current region before we
+        * pop it off the stack.  Pop the stack.  And then print
+        * the perf message at the new (shallower) level so that
+        * it lines up with the corresponding push/enter.
+        */
+       us_elapsed_region = tr2tls_region_elasped_self(us_now);
+
+       tr2tls_pop_self();
+
+       /*
+        * We expect each target function to treat 'ap' as constant
+        * and use va_copy.
+        */
+       for_each_wanted_builtin (j, tgt_j)
+               if (tgt_j->pfn_region_leave_printf_va_fl)
+                       tgt_j->pfn_region_leave_printf_va_fl(
+                               file, line, us_elapsed_absolute,
+                               us_elapsed_region, category, label, repo, fmt,
+                               ap);
+}
+
+void trace2_region_leave_fl(const char *file, int line, const char *category,
+                           const char *label, const struct repository *repo)
+{
+       trace2_region_leave_printf_va_fl(file, line, category, label, repo,
+                                        NULL, NULL);
+}
+
+void trace2_region_leave_printf_fl(const char *file, int line,
+                                  const char *category, const char *label,
+                                  const struct repository *repo,
+                                  const char *fmt, ...)
+{
+       va_list ap;
+
+       va_start(ap, fmt);
+       trace2_region_leave_printf_va_fl(file, line, category, label, repo, fmt,
+                                        ap);
+       va_end(ap);
+}
+
+#ifndef HAVE_VARIADIC_MACROS
+void trace2_region_leave_printf(const char *category, const char *label,
+                               const struct repository *repo, const char *fmt,
+                               ...)
+{
+       va_list ap;
+
+       va_start(ap, fmt);
+       trace2_region_leave_printf_va_fl(NULL, 0, category, label, repo, fmt,
+                                        ap);
+       va_end(ap);
+}
+#endif
+
+void trace2_data_string_fl(const char *file, int line, const char *category,
+                          const struct repository *repo, const char *key,
+                          const char *value)
+{
+       struct tr2_tgt *tgt_j;
+       int j;
+       uint64_t us_now;
+       uint64_t us_elapsed_absolute;
+       uint64_t us_elapsed_region;
+
+       if (!trace2_enabled)
+               return;
+
+       us_now = getnanotime() / 1000;
+       us_elapsed_absolute = tr2tls_absolute_elapsed(us_now);
+       us_elapsed_region = tr2tls_region_elasped_self(us_now);
+
+       for_each_wanted_builtin (j, tgt_j)
+               if (tgt_j->pfn_data_fl)
+                       tgt_j->pfn_data_fl(file, line, us_elapsed_absolute,
+                                          us_elapsed_region, category, repo,
+                                          key, value);
+}
+
+void trace2_data_intmax_fl(const char *file, int line, const char *category,
+                          const struct repository *repo, const char *key,
+                          intmax_t value)
+{
+       struct strbuf buf_string = STRBUF_INIT;
+
+       if (!trace2_enabled)
+               return;
+
+       strbuf_addf(&buf_string, "%" PRIdMAX, value);
+       trace2_data_string_fl(file, line, category, repo, key, buf_string.buf);
+       strbuf_release(&buf_string);
+}
+
+void trace2_data_json_fl(const char *file, int line, const char *category,
+                        const struct repository *repo, const char *key,
+                        const struct json_writer *value)
+{
+       struct tr2_tgt *tgt_j;
+       int j;
+       uint64_t us_now;
+       uint64_t us_elapsed_absolute;
+       uint64_t us_elapsed_region;
+
+       if (!trace2_enabled)
+               return;
+
+       us_now = getnanotime() / 1000;
+       us_elapsed_absolute = tr2tls_absolute_elapsed(us_now);
+       us_elapsed_region = tr2tls_region_elasped_self(us_now);
+
+       for_each_wanted_builtin (j, tgt_j)
+               if (tgt_j->pfn_data_fl)
+                       tgt_j->pfn_data_json_fl(file, line, us_elapsed_absolute,
+                                               us_elapsed_region, category,
+                                               repo, key, value);
+}
+
+void trace2_printf_va_fl(const char *file, int line, const char *fmt,
+                        va_list ap)
+{
+       struct tr2_tgt *tgt_j;
+       int j;
+       uint64_t us_now;
+       uint64_t us_elapsed_absolute;
+
+       if (!trace2_enabled)
+               return;
+
+       us_now = getnanotime() / 1000;
+       us_elapsed_absolute = tr2tls_absolute_elapsed(us_now);
+
+       /*
+        * We expect each target function to treat 'ap' as constant
+        * and use va_copy.
+        */
+       for_each_wanted_builtin (j, tgt_j)
+               if (tgt_j->pfn_printf_va_fl)
+                       tgt_j->pfn_printf_va_fl(file, line, us_elapsed_absolute,
+                                               fmt, ap);
+}
+
+void trace2_printf_fl(const char *file, int line, const char *fmt, ...)
+{
+       va_list ap;
+
+       va_start(ap, fmt);
+       trace2_printf_va_fl(file, line, fmt, ap);
+       va_end(ap);
+}
+
+#ifndef HAVE_VARIADIC_MACROS
+void trace2_printf(const char *fmt, ...)
+{
+       va_list ap;
+
+       va_start(ap, fmt);
+       trace2_printf_va_fl(NULL, 0, fmt, ap);
+       va_end(ap);
+}
+#endif
diff --git a/trace2.h b/trace2.h
new file mode 100644 (file)
index 0000000..ae5020d
--- /dev/null
+++ b/trace2.h
@@ -0,0 +1,385 @@
+#ifndef TRACE2_H
+#define TRACE2_H
+
+struct child_process;
+struct repository;
+struct json_writer;
+
+/*
+ * The public TRACE2 routines are grouped into the following groups:
+ *
+ * [] trace2_initialize -- initialization.
+ * [] trace2_cmd_*      -- emit command/control messages.
+ * [] trace2_child*     -- emit child start/stop messages.
+ * [] trace2_exec*      -- emit exec start/stop messages.
+ * [] trace2_thread*    -- emit thread start/stop messages.
+ * [] trace2_def*       -- emit definition/parameter mesasges.
+ * [] trace2_region*    -- emit region nesting messages.
+ * [] trace2_data*      -- emit region/thread/repo data messages.
+ * [] trace2_printf*    -- legacy trace[1] messages.
+ */
+
+/*
+ * Initialize TRACE2 tracing facility if any of the builtin TRACE2
+ * targets are enabled in the environment.  Emits a 'version' event.
+ *
+ * Cleanup/Termination is handled automatically by a registered
+ * atexit() routine.
+ */
+void trace2_initialize_fl(const char *file, int line);
+
+#define trace2_initialize() trace2_initialize_fl(__FILE__, __LINE__)
+
+/*
+ * Return true if trace2 is enabled.
+ */
+int trace2_is_enabled(void);
+
+/*
+ * Emit a 'start' event with the original (unmodified) argv.
+ */
+void trace2_cmd_start_fl(const char *file, int line, const char **argv);
+
+#define trace2_cmd_start(argv) trace2_cmd_start_fl(__FILE__, __LINE__, (argv))
+
+/*
+ * Emit an 'exit' event.
+ *
+ * Write the exit-code that will be passed to exit() or returned
+ * from main().
+ *
+ * Use this prior to actually calling exit().
+ * See "#define exit()" in git-compat-util.h
+ */
+int trace2_cmd_exit_fl(const char *file, int line, int code);
+
+#define trace2_cmd_exit(code) (trace2_cmd_exit_fl(__FILE__, __LINE__, (code)))
+
+/*
+ * Emit an 'error' event.
+ *
+ * Write an error message to the TRACE2 targets.
+ */
+void trace2_cmd_error_va_fl(const char *file, int line, const char *fmt,
+                           va_list ap);
+
+#define trace2_cmd_error_va(fmt, ap) \
+       trace2_cmd_error_va_fl(__FILE__, __LINE__, (fmt), (ap))
+
+/*
+ * Emit a 'pathname' event with the canonical pathname of the current process
+ * This gives post-processors a simple field to identify the command without
+ * having to parse the argv.  For example, to distinguish invocations from
+ * installed versus debug executables.
+ */
+void trace2_cmd_path_fl(const char *file, int line, const char *pathname);
+
+#define trace2_cmd_path(p) trace2_cmd_path_fl(__FILE__, __LINE__, (p))
+
+/*
+ * Emit a 'cmd_name' event with the canonical name of the command.
+ * This gives post-processors a simple field to identify the command
+ * without having to parse the argv.
+ */
+void trace2_cmd_name_fl(const char *file, int line, const char *name);
+
+#define trace2_cmd_name(v) trace2_cmd_name_fl(__FILE__, __LINE__, (v))
+
+/*
+ * Emit a 'cmd_mode' event to further describe the command being run.
+ * For example, "checkout" can checkout a single file or can checkout a
+ * different branch.  This gives post-processors a simple field to compare
+ * equivalent commands without having to parse the argv.
+ */
+void trace2_cmd_mode_fl(const char *file, int line, const char *mode);
+
+#define trace2_cmd_mode(sv) trace2_cmd_mode_fl(__FILE__, __LINE__, (sv))
+
+/*
+ * Emit an 'alias' expansion event.
+ */
+void trace2_cmd_alias_fl(const char *file, int line, const char *alias,
+                        const char **argv);
+
+#define trace2_cmd_alias(alias, argv) \
+       trace2_cmd_alias_fl(__FILE__, __LINE__, (alias), (argv))
+
+/*
+ * Emit one or more 'def_param' events for "interesting" configuration
+ * settings.
+ *
+ * The environment variable "GIT_TR2_CONFIG_PARAMS" can be set to a
+ * list of patterns considered important.  For example:
+ *
+ *    GIT_TR2_CONFIG_PARAMS="core.*,remote.*.url"
+ *
+ * Note: this routine does a read-only iteration on the config data
+ * (using read_early_config()), so it must not be called until enough
+ * of the process environment has been established.  This includes the
+ * location of the git and worktree directories, expansion of any "-c"
+ * and "-C" command line options, and etc.
+ */
+void trace2_cmd_list_config_fl(const char *file, int line);
+
+#define trace2_cmd_list_config() trace2_cmd_list_config_fl(__FILE__, __LINE__)
+
+/*
+ * Emit a "def_param" event for the given config key/value pair IF
+ * we consider the key to be "interesting".
+ *
+ * Use this for new/updated config settings created/updated after
+ * trace2_cmd_list_config() is called.
+ */
+void trace2_cmd_set_config_fl(const char *file, int line, const char *key,
+                             const char *value);
+
+#define trace2_cmd_set_config(k, v) \
+       trace2_cmd_set_config_fl(__FILE__, __LINE__, (k), (v))
+
+/*
+ * Emit a 'child_start' event prior to spawning a child process.
+ *
+ * Before calling optionally set "cmd->trace2_child_class" to a string
+ * describing the type of the child process.  For example, "editor" or
+ * "pager".
+ */
+void trace2_child_start_fl(const char *file, int line,
+                          struct child_process *cmd);
+
+#define trace2_child_start(cmd) trace2_child_start_fl(__FILE__, __LINE__, (cmd))
+
+/*
+ * Emit a 'child_exit' event after the child process completes.
+ */
+void trace2_child_exit_fl(const char *file, int line, struct child_process *cmd,
+                         int child_exit_code);
+
+#define trace2_child_exit(cmd, code) \
+       trace2_child_exit_fl(__FILE__, __LINE__, (cmd), (code))
+
+/*
+ * Emit an 'exec' event prior to calling one of exec(), execv(),
+ * execvp(), and etc.  On Unix-derived systems, this will be the
+ * last event emitted for the current process, unless the exec
+ * fails.  On Windows, exec() behaves like 'child_start' and a
+ * waitpid(), so additional events may be emitted.
+ *
+ * Returns the "exec_id".
+ */
+int trace2_exec_fl(const char *file, int line, const char *exe,
+                  const char **argv);
+
+#define trace2_exec(exe, argv) trace2_exec_fl(__FILE__, __LINE__, (exe), (argv))
+
+/*
+ * Emit an 'exec_result' when possible.  On Unix-derived systems,
+ * this should be called after exec() returns (which only happens
+ * when there is an error starting the new process).  On Windows,
+ * this should be called after the waitpid().
+ *
+ * The "exec_id" should be the value returned from trace2_exec().
+ */
+void trace2_exec_result_fl(const char *file, int line, int exec_id, int code);
+
+#define trace2_exec_result(id, code) \
+       trace2_exec_result_fl(__FILE__, __LINE__, (id), (code))
+
+/*
+ * Emit a 'thread_start' event.  This must be called from inside the
+ * thread-proc to set up the trace2 TLS data for the thread.
+ *
+ * Thread names should be descriptive, like "preload_index".
+ * Thread names will be decorated with an instance number automatically.
+ */
+void trace2_thread_start_fl(const char *file, int line,
+                           const char *thread_name);
+
+#define trace2_thread_start(thread_name) \
+       trace2_thread_start_fl(__FILE__, __LINE__, (thread_name))
+
+/*
+ * Emit a 'thread_exit' event.  This must be called from inside the
+ * thread-proc to report thread-specific data and cleanup TLS data
+ * for the thread.
+ */
+void trace2_thread_exit_fl(const char *file, int line);
+
+#define trace2_thread_exit() trace2_thread_exit_fl(__FILE__, __LINE__)
+
+/*
+ * Emit a 'param' event.
+ *
+ * Write a "<param> = <value>" pair describing some aspect of the
+ * run such as an important configuration setting or command line
+ * option that significantly changes command behavior.
+ */
+void trace2_def_param_fl(const char *file, int line, const char *param,
+                        const char *value);
+
+#define trace2_def_param(param, value) \
+       trace2_def_param_fl(__FILE__, __LINE__, (param), (value))
+
+/*
+ * Tell trace2 about a newly instantiated repo object and assign
+ * a trace2-repo-id to be used in subsequent activity events.
+ *
+ * Emits a 'worktree' event for this repo instance.
+ */
+void trace2_def_repo_fl(const char *file, int line, struct repository *repo);
+
+#define trace2_def_repo(repo) trace2_def_repo_fl(__FILE__, __LINE__, repo)
+
+/*
+ * Emit a 'region_enter' event for <category>.<label> with optional
+ * repo-id and printf message.
+ *
+ * Enter a new nesting level on the current thread and remember the
+ * current time.  This controls the indenting of all subsequent events
+ * on this thread.
+ */
+void trace2_region_enter_fl(const char *file, int line, const char *category,
+                           const char *label, const struct repository *repo);
+
+#define trace2_region_enter(category, label, repo) \
+       trace2_region_enter_fl(__FILE__, __LINE__, (category), (label), (repo))
+
+void trace2_region_enter_printf_va_fl(const char *file, int line,
+                                     const char *category, const char *label,
+                                     const struct repository *repo,
+                                     const char *fmt, va_list ap);
+
+#define trace2_region_enter_printf_va(category, label, repo, fmt, ap)    \
+       trace2_region_enter_printf_va_fl(__FILE__, __LINE__, (category), \
+                                        (label), (repo), (fmt), (ap))
+
+void trace2_region_enter_printf_fl(const char *file, int line,
+                                  const char *category, const char *label,
+                                  const struct repository *repo,
+                                  const char *fmt, ...);
+
+#ifdef HAVE_VARIADIC_MACROS
+#define trace2_region_enter_printf(category, label, repo, ...)                 \
+       trace2_region_enter_printf_fl(__FILE__, __LINE__, (category), (label), \
+                                     (repo), __VA_ARGS__)
+#else
+/* clang-format off */
+__attribute__((format (region_enter_printf, 4, 5)))
+void trace2_region_enter_printf(const char *category, const char *label,
+                               const struct repository *repo, const char *fmt,
+                               ...);
+/* clang-format on */
+#endif
+
+/*
+ * Emit a 'region_leave' event for <category>.<label> with optional
+ * repo-id and printf message.
+ *
+ * Leave current nesting level and report the elapsed time spent
+ * in this nesting level.
+ */
+void trace2_region_leave_fl(const char *file, int line, const char *category,
+                           const char *label, const struct repository *repo);
+
+#define trace2_region_leave(category, label, repo) \
+       trace2_region_leave_fl(__FILE__, __LINE__, (category), (label), (repo))
+
+void trace2_region_leave_printf_va_fl(const char *file, int line,
+                                     const char *category, const char *label,
+                                     const struct repository *repo,
+                                     const char *fmt, va_list ap);
+
+#define trace2_region_leave_printf_va(category, label, repo, fmt, ap)    \
+       trace2_region_leave_printf_va_fl(__FILE__, __LINE__, (category), \
+                                        (label), (repo), (fmt), (ap))
+
+void trace2_region_leave_printf_fl(const char *file, int line,
+                                  const char *category, const char *label,
+                                  const struct repository *repo,
+                                  const char *fmt, ...);
+
+#ifdef HAVE_VARIADIC_MACROS
+#define trace2_region_leave_printf(category, label, repo, ...)                 \
+       trace2_region_leave_printf_fl(__FILE__, __LINE__, (category), (label), \
+                                     (repo), __VA_ARGS__)
+#else
+/* clang-format off */
+__attribute__((format (region_leave_printf, 4, 5)))
+void trace2_region_leave_printf(const char *category, const char *label,
+                               const struct repository *repo, const char *fmt,
+                               ...);
+/* clang-format on */
+#endif
+
+/*
+ * Emit a key-value pair 'data' event of the form <category>.<key> = <value>.
+ * This event implicitly contains information about thread, nesting region,
+ * and optional repo-id.
+ *
+ * On event-based TRACE2 targets, this generates a 'data' event suitable
+ * for post-processing.  On printf-based TRACE2 targets, this is converted
+ * into a fixed-format printf message.
+ */
+void trace2_data_string_fl(const char *file, int line, const char *category,
+                          const struct repository *repo, const char *key,
+                          const char *value);
+
+#define trace2_data_string(category, repo, key, value)                       \
+       trace2_data_string_fl(__FILE__, __LINE__, (category), (repo), (key), \
+                             (value))
+
+void trace2_data_intmax_fl(const char *file, int line, const char *category,
+                          const struct repository *repo, const char *key,
+                          intmax_t value);
+
+#define trace2_data_intmax(category, repo, key, value)                       \
+       trace2_data_intmax_fl(__FILE__, __LINE__, (category), (repo), (key), \
+                             (value))
+
+void trace2_data_json_fl(const char *file, int line, const char *category,
+                        const struct repository *repo, const char *key,
+                        const struct json_writer *jw);
+
+#define trace2_data_json(category, repo, key, value)                       \
+       trace2_data_json_fl(__FILE__, __LINE__, (category), (repo), (key), \
+                           (value))
+
+/*
+ * Emit a 'printf' event.
+ *
+ * Write an arbitrary formatted message to the TRACE2 targets.  These
+ * text messages should be considered as human-readable strings without
+ * any formatting guidelines.  Post-processors may choose to ignore
+ * them.
+ */
+void trace2_printf_va_fl(const char *file, int line, const char *fmt,
+                        va_list ap);
+
+#define trace2_printf_va(fmt, ap) \
+       trace2_printf_va_fl(__FILE__, __LINE__, (fmt), (ap))
+
+void trace2_printf_fl(const char *file, int line, const char *fmt, ...);
+
+#ifdef HAVE_VARIADIC_MACROS
+#define trace2_printf(...) trace2_printf_fl(__FILE__, __LINE__, __VA_ARGS__)
+#else
+/* clang-format off */
+__attribute__((format (printf, 1, 2)))
+void trace2_printf(const char *fmt, ...);
+/* clang-format on */
+#endif
+
+/*
+ * Optional platform-specific code to dump information about the
+ * current and any parent process(es).  This is intended to allow
+ * post-processors to know who spawned this git instance and anything
+ * else the platform may be able to tell us about the current process.
+ */
+#if defined(GIT_WINDOWS_NATIVE)
+void trace2_collect_process_info(void);
+#else
+#define trace2_collect_process_info() \
+       do {                          \
+       } while (0)
+#endif
+
+#endif /* TRACE2_H */
diff --git a/trace2/tr2_cfg.c b/trace2/tr2_cfg.c
new file mode 100644 (file)
index 0000000..b329921
--- /dev/null
@@ -0,0 +1,90 @@
+#include "cache.h"
+#include "config.h"
+#include "tr2_cfg.h"
+
+#define TR2_ENVVAR_CFG_PARAM "GIT_TR2_CONFIG_PARAMS"
+
+static struct strbuf **tr2_cfg_patterns;
+static int tr2_cfg_count_patterns;
+static int tr2_cfg_loaded;
+
+/*
+ * Parse a string containing a comma-delimited list of config keys
+ * or wildcard patterns into a list of strbufs.
+ */
+static int tr2_cfg_load_patterns(void)
+{
+       struct strbuf **s;
+       const char *envvar;
+
+       if (tr2_cfg_loaded)
+               return tr2_cfg_count_patterns;
+       tr2_cfg_loaded = 1;
+
+       envvar = getenv(TR2_ENVVAR_CFG_PARAM);
+       if (!envvar || !*envvar)
+               return tr2_cfg_count_patterns;
+
+       tr2_cfg_patterns = strbuf_split_buf(envvar, strlen(envvar), ',', -1);
+       for (s = tr2_cfg_patterns; *s; s++) {
+               struct strbuf *buf = *s;
+
+               if (buf->len && buf->buf[buf->len - 1] == ',')
+                       strbuf_setlen(buf, buf->len - 1);
+               strbuf_trim_trailing_newline(*s);
+               strbuf_trim(*s);
+       }
+
+       tr2_cfg_count_patterns = s - tr2_cfg_patterns;
+       return tr2_cfg_count_patterns;
+}
+
+void tr2_cfg_free_patterns(void)
+{
+       if (tr2_cfg_patterns)
+               strbuf_list_free(tr2_cfg_patterns);
+       tr2_cfg_count_patterns = 0;
+       tr2_cfg_loaded = 0;
+}
+
+struct tr2_cfg_data {
+       const char *file;
+       int line;
+};
+
+/*
+ * See if the given config key matches any of our patterns of interest.
+ */
+static int tr2_cfg_cb(const char *key, const char *value, void *d)
+{
+       struct strbuf **s;
+       struct tr2_cfg_data *data = (struct tr2_cfg_data *)d;
+
+       for (s = tr2_cfg_patterns; *s; s++) {
+               struct strbuf *buf = *s;
+               int wm = wildmatch(buf->buf, key, WM_CASEFOLD);
+               if (wm == WM_MATCH) {
+                       trace2_def_param_fl(data->file, data->line, key, value);
+                       return 0;
+               }
+       }
+
+       return 0;
+}
+
+void tr2_cfg_list_config_fl(const char *file, int line)
+{
+       struct tr2_cfg_data data = { file, line };
+
+       if (tr2_cfg_load_patterns() > 0)
+               read_early_config(tr2_cfg_cb, &data);
+}
+
+void tr2_cfg_set_fl(const char *file, int line, const char *key,
+                   const char *value)
+{
+       struct tr2_cfg_data data = { file, line };
+
+       if (tr2_cfg_load_patterns() > 0)
+               tr2_cfg_cb(key, value, &data);
+}
diff --git a/trace2/tr2_cfg.h b/trace2/tr2_cfg.h
new file mode 100644 (file)
index 0000000..d9c98f6
--- /dev/null
@@ -0,0 +1,19 @@
+#ifndef TR2_CFG_H
+#define TR2_CFG_H
+
+/*
+ * Iterate over all config settings and emit 'def_param' events for the
+ * "interesting" ones to TRACE2.
+ */
+void tr2_cfg_list_config_fl(const char *file, int line);
+
+/*
+ * Emit a "def_param" event for the given key/value pair IF we consider
+ * the key to be "interesting".
+ */
+void tr2_cfg_set_fl(const char *file, int line, const char *key,
+                   const char *value);
+
+void tr2_cfg_free_patterns(void);
+
+#endif /* TR2_CFG_H */
diff --git a/trace2/tr2_cmd_name.c b/trace2/tr2_cmd_name.c
new file mode 100644 (file)
index 0000000..e999592
--- /dev/null
@@ -0,0 +1,30 @@
+#include "cache.h"
+#include "trace2/tr2_cmd_name.h"
+
+#define TR2_ENVVAR_PARENT_NAME "GIT_TR2_PARENT_NAME"
+
+static struct strbuf tr2cmdname_hierarchy = STRBUF_INIT;
+
+void tr2_cmd_name_append_hierarchy(const char *name)
+{
+       const char *parent_name = getenv(TR2_ENVVAR_PARENT_NAME);
+
+       strbuf_reset(&tr2cmdname_hierarchy);
+       if (parent_name && *parent_name) {
+               strbuf_addstr(&tr2cmdname_hierarchy, parent_name);
+               strbuf_addch(&tr2cmdname_hierarchy, '/');
+       }
+       strbuf_addstr(&tr2cmdname_hierarchy, name);
+
+       setenv(TR2_ENVVAR_PARENT_NAME, tr2cmdname_hierarchy.buf, 1);
+}
+
+const char *tr2_cmd_name_get_hierarchy(void)
+{
+       return tr2cmdname_hierarchy.buf;
+}
+
+void tr2_cmd_name_release(void)
+{
+       strbuf_release(&tr2cmdname_hierarchy);
+}
diff --git a/trace2/tr2_cmd_name.h b/trace2/tr2_cmd_name.h
new file mode 100644 (file)
index 0000000..ab70b67
--- /dev/null
@@ -0,0 +1,24 @@
+#ifndef TR2_CMD_NAME_H
+#define TR2_CMD_NAME_H
+
+/*
+ * Append the current command name to the list being maintained
+ * in the environment.
+ *
+ * The hierarchy for a top-level git command is just the current
+ * command name.  For a child git process, the hierarchy includes the
+ * names of the parent processes.
+ *
+ * The hierarchy for the current process will be exported to the
+ * environment and inherited by child processes.
+ */
+void tr2_cmd_name_append_hierarchy(const char *name);
+
+/*
+ * Get the command name hierarchy for the current process.
+ */
+const char *tr2_cmd_name_get_hierarchy(void);
+
+void tr2_cmd_name_release(void);
+
+#endif /* TR2_CMD_NAME_H */
diff --git a/trace2/tr2_dst.c b/trace2/tr2_dst.c
new file mode 100644 (file)
index 0000000..fd490a4
--- /dev/null
@@ -0,0 +1,252 @@
+#include "cache.h"
+#include "trace2/tr2_dst.h"
+
+/*
+ * If a Trace2 target cannot be opened for writing, we should issue a
+ * warning to stderr, but this is very annoying if the target is a pipe
+ * or socket and beyond the user's control -- especially since every
+ * git command (and sub-command) will print the message.  So we silently
+ * eat these warnings and just discard the trace data.
+ *
+ * Enable the following environment variable to see these warnings.
+ */
+#define TR2_ENVVAR_DST_DEBUG "GIT_TR2_DST_DEBUG"
+
+static int tr2_dst_want_warning(void)
+{
+       static int tr2env_dst_debug = -1;
+
+       if (tr2env_dst_debug == -1) {
+               const char *env_value = getenv(TR2_ENVVAR_DST_DEBUG);
+               if (!env_value || !*env_value)
+                       tr2env_dst_debug = 0;
+               else
+                       tr2env_dst_debug = atoi(env_value) > 0;
+       }
+
+       return tr2env_dst_debug;
+}
+
+void tr2_dst_trace_disable(struct tr2_dst *dst)
+{
+       if (dst->need_close)
+               close(dst->fd);
+       dst->fd = 0;
+       dst->initialized = 1;
+       dst->need_close = 0;
+}
+
+static int tr2_dst_try_path(struct tr2_dst *dst, const char *tgt_value)
+{
+       int fd = open(tgt_value, O_WRONLY | O_APPEND | O_CREAT, 0666);
+       if (fd == -1) {
+               if (tr2_dst_want_warning())
+                       warning("trace2: could not open '%s' for '%s' tracing: %s",
+                               tgt_value, dst->env_var_name, strerror(errno));
+
+               tr2_dst_trace_disable(dst);
+               return 0;
+       }
+
+       dst->fd = fd;
+       dst->need_close = 1;
+       dst->initialized = 1;
+
+       return dst->fd;
+}
+
+#ifndef NO_UNIX_SOCKETS
+#define PREFIX_AF_UNIX "af_unix:"
+#define PREFIX_AF_UNIX_STREAM "af_unix:stream:"
+#define PREFIX_AF_UNIX_DGRAM "af_unix:dgram:"
+
+static int tr2_dst_try_uds_connect(const char *path, int sock_type, int *out_fd)
+{
+       int fd;
+       struct sockaddr_un sa;
+
+       fd = socket(AF_UNIX, sock_type, 0);
+       if (fd == -1)
+               return errno;
+
+       sa.sun_family = AF_UNIX;
+       strlcpy(sa.sun_path, path, sizeof(sa.sun_path));
+
+       if (connect(fd, (struct sockaddr *)&sa, sizeof(sa)) == -1) {
+               int e = errno;
+               close(fd);
+               return e;
+       }
+
+       *out_fd = fd;
+       return 0;
+}
+
+#define TR2_DST_UDS_TRY_STREAM (1 << 0)
+#define TR2_DST_UDS_TRY_DGRAM  (1 << 1)
+
+static int tr2_dst_try_unix_domain_socket(struct tr2_dst *dst,
+                                         const char *tgt_value)
+{
+       unsigned int uds_try = 0;
+       int fd;
+       int e;
+       const char *path = NULL;
+
+       /*
+        * Allow "af_unix:[<type>:]<absolute_path>"
+        *
+        * Trace2 always writes complete individual messages (without
+        * chunking), so we can talk to either DGRAM or STREAM type sockets.
+        *
+        * Allow the user to explicitly request the socket type.
+        *
+        * If they omit the socket type, try one and then the other.
+        */
+
+       if (skip_prefix(tgt_value, PREFIX_AF_UNIX_STREAM, &path))
+               uds_try |= TR2_DST_UDS_TRY_STREAM;
+
+       else if (skip_prefix(tgt_value, PREFIX_AF_UNIX_DGRAM, &path))
+               uds_try |= TR2_DST_UDS_TRY_DGRAM;
+
+       else if (skip_prefix(tgt_value, PREFIX_AF_UNIX, &path))
+               uds_try |= TR2_DST_UDS_TRY_STREAM | TR2_DST_UDS_TRY_DGRAM;
+
+       if (!path || !*path) {
+               if (tr2_dst_want_warning())
+                       warning("trace2: invalid AF_UNIX value '%s' for '%s' tracing",
+                               tgt_value, dst->env_var_name);
+
+               tr2_dst_trace_disable(dst);
+               return 0;
+       }
+
+       if (!is_absolute_path(path) ||
+           strlen(path) >= sizeof(((struct sockaddr_un *)0)->sun_path)) {
+               if (tr2_dst_want_warning())
+                       warning("trace2: invalid AF_UNIX path '%s' for '%s' tracing",
+                               path, dst->env_var_name);
+
+               tr2_dst_trace_disable(dst);
+               return 0;
+       }
+
+       if (uds_try & TR2_DST_UDS_TRY_STREAM) {
+               e = tr2_dst_try_uds_connect(path, SOCK_STREAM, &fd);
+               if (!e)
+                       goto connected;
+               if (e != EPROTOTYPE)
+                       goto error;
+       }
+       if (uds_try & TR2_DST_UDS_TRY_DGRAM) {
+               e = tr2_dst_try_uds_connect(path, SOCK_DGRAM, &fd);
+               if (!e)
+                       goto connected;
+       }
+
+error:
+       if (tr2_dst_want_warning())
+               warning("trace2: could not connect to socket '%s' for '%s' tracing: %s",
+                       path, dst->env_var_name, strerror(e));
+
+       tr2_dst_trace_disable(dst);
+       return 0;
+
+connected:
+       dst->fd = fd;
+       dst->need_close = 1;
+       dst->initialized = 1;
+
+       return dst->fd;
+}
+#endif
+
+static void tr2_dst_malformed_warning(struct tr2_dst *dst,
+                                     const char *tgt_value)
+{
+       struct strbuf buf = STRBUF_INIT;
+
+       strbuf_addf(&buf, "trace2: unknown value for '%s': '%s'",
+                   dst->env_var_name, tgt_value);
+       warning("%s", buf.buf);
+
+       strbuf_release(&buf);
+}
+
+int tr2_dst_get_trace_fd(struct tr2_dst *dst)
+{
+       const char *tgt_value;
+
+       /* don't open twice */
+       if (dst->initialized)
+               return dst->fd;
+
+       dst->initialized = 1;
+
+       tgt_value = getenv(dst->env_var_name);
+
+       if (!tgt_value || !strcmp(tgt_value, "") || !strcmp(tgt_value, "0") ||
+           !strcasecmp(tgt_value, "false")) {
+               dst->fd = 0;
+               return dst->fd;
+       }
+
+       if (!strcmp(tgt_value, "1") || !strcasecmp(tgt_value, "true")) {
+               dst->fd = STDERR_FILENO;
+               return dst->fd;
+       }
+
+       if (strlen(tgt_value) == 1 && isdigit(*tgt_value)) {
+               dst->fd = atoi(tgt_value);
+               return dst->fd;
+       }
+
+       if (is_absolute_path(tgt_value))
+               return tr2_dst_try_path(dst, tgt_value);
+
+#ifndef NO_UNIX_SOCKETS
+       if (starts_with(tgt_value, PREFIX_AF_UNIX))
+               return tr2_dst_try_unix_domain_socket(dst, tgt_value);
+#endif
+
+       /* Always warn about malformed values. */
+       tr2_dst_malformed_warning(dst, tgt_value);
+       tr2_dst_trace_disable(dst);
+       return 0;
+}
+
+int tr2_dst_trace_want(struct tr2_dst *dst)
+{
+       return !!tr2_dst_get_trace_fd(dst);
+}
+
+void tr2_dst_write_line(struct tr2_dst *dst, struct strbuf *buf_line)
+{
+       int fd = tr2_dst_get_trace_fd(dst);
+
+       strbuf_complete_line(buf_line); /* ensure final NL on buffer */
+
+       /*
+        * We do not use write_in_full() because we do not want
+        * a short-write to try again.  We are using O_APPEND mode
+        * files and the kernel handles the atomic seek+write. If
+        * another thread or git process is concurrently writing to
+        * this fd or file, our remainder-write may not be contiguous
+        * with our initial write of this message.  And that will
+        * confuse readers.  So just don't bother.
+        *
+        * It is assumed that TRACE2 messages are short enough that
+        * the system can write them in 1 attempt and we won't see
+        * a short-write.
+        *
+        * If we get an IO error, just close the trace dst.
+        */
+       if (write(fd, buf_line->buf, buf_line->len) >= 0)
+               return;
+
+       if (tr2_dst_want_warning())
+               warning("unable to write trace to '%s': %s", dst->env_var_name,
+                       strerror(errno));
+       tr2_dst_trace_disable(dst);
+}
diff --git a/trace2/tr2_dst.h b/trace2/tr2_dst.h
new file mode 100644 (file)
index 0000000..9a64f05
--- /dev/null
@@ -0,0 +1,36 @@
+#ifndef TR2_DST_H
+#define TR2_DST_H
+
+struct strbuf;
+
+struct tr2_dst {
+       const char *const env_var_name;
+       int fd;
+       unsigned int initialized : 1;
+       unsigned int need_close : 1;
+};
+
+/*
+ * Disable TRACE2 on the destination.  In TRACE2 a destination (DST)
+ * wraps a file descriptor; it is associated with a TARGET which
+ * defines the formatting.
+ */
+void tr2_dst_trace_disable(struct tr2_dst *dst);
+
+/*
+ * Return the file descriptor for the DST.
+ * If 0, the dst is closed or disabled.
+ */
+int tr2_dst_get_trace_fd(struct tr2_dst *dst);
+
+/*
+ * Return true if the DST is opened for writing.
+ */
+int tr2_dst_trace_want(struct tr2_dst *dst);
+
+/*
+ * Write a single line/message to the trace file.
+ */
+void tr2_dst_write_line(struct tr2_dst *dst, struct strbuf *buf_line);
+
+#endif /* TR2_DST_H */
diff --git a/trace2/tr2_sid.c b/trace2/tr2_sid.c
new file mode 100644 (file)
index 0000000..984524a
--- /dev/null
@@ -0,0 +1,67 @@
+#include "cache.h"
+#include "trace2/tr2_sid.h"
+
+#define TR2_ENVVAR_PARENT_SID "GIT_TR2_PARENT_SID"
+
+static struct strbuf tr2sid_buf = STRBUF_INIT;
+static int tr2sid_nr_git_parents;
+
+/*
+ * Compute a "unique" session id (SID) for the current process.  This allows
+ * all events from this process to have a single label (much like a PID).
+ *
+ * Export this into our environment so that all child processes inherit it.
+ *
+ * If we were started by another git instance, use our parent's SID as a
+ * prefix.  (This lets us track parent/child relationships even if there
+ * is an intermediate shell process.)
+ *
+ * Additionally, count the number of nested git processes.
+ */
+static void tr2_sid_compute(void)
+{
+       uint64_t us_now;
+       const char *parent_sid;
+
+       if (tr2sid_buf.len)
+               return;
+
+       parent_sid = getenv(TR2_ENVVAR_PARENT_SID);
+       if (parent_sid && *parent_sid) {
+               const char *p;
+               for (p = parent_sid; *p; p++)
+                       if (*p == '/')
+                               tr2sid_nr_git_parents++;
+
+               strbuf_addstr(&tr2sid_buf, parent_sid);
+               strbuf_addch(&tr2sid_buf, '/');
+               tr2sid_nr_git_parents++;
+       }
+
+       us_now = getnanotime() / 1000;
+       strbuf_addf(&tr2sid_buf, "%" PRIuMAX "-%" PRIdMAX, (uintmax_t)us_now,
+                   (intmax_t)getpid());
+
+       setenv(TR2_ENVVAR_PARENT_SID, tr2sid_buf.buf, 1);
+}
+
+const char *tr2_sid_get(void)
+{
+       if (!tr2sid_buf.len)
+               tr2_sid_compute();
+
+       return tr2sid_buf.buf;
+}
+
+int tr2_sid_depth(void)
+{
+       if (!tr2sid_buf.len)
+               tr2_sid_compute();
+
+       return tr2sid_nr_git_parents;
+}
+
+void tr2_sid_release(void)
+{
+       strbuf_release(&tr2sid_buf);
+}
diff --git a/trace2/tr2_sid.h b/trace2/tr2_sid.h
new file mode 100644 (file)
index 0000000..9bef321
--- /dev/null
@@ -0,0 +1,18 @@
+#ifndef TR2_SID_H
+#define TR2_SID_H
+
+/*
+ * Get our session id. Compute if necessary.
+ */
+const char *tr2_sid_get(void);
+
+/*
+ * Get our process depth.  A top-level git process invoked from the
+ * command line will have depth=0.  A child git process will have
+ * depth=1 and so on.
+ */
+int tr2_sid_depth(void);
+
+void tr2_sid_release(void);
+
+#endif /* TR2_SID_H */
diff --git a/trace2/tr2_tbuf.c b/trace2/tr2_tbuf.c
new file mode 100644 (file)
index 0000000..0844910
--- /dev/null
@@ -0,0 +1,32 @@
+#include "cache.h"
+#include "tr2_tbuf.h"
+
+void tr2_tbuf_local_time(struct tr2_tbuf *tb)
+{
+       struct timeval tv;
+       struct tm tm;
+       time_t secs;
+
+       gettimeofday(&tv, NULL);
+       secs = tv.tv_sec;
+       localtime_r(&secs, &tm);
+
+       xsnprintf(tb->buf, sizeof(tb->buf), "%02d:%02d:%02d.%06ld", tm.tm_hour,
+                 tm.tm_min, tm.tm_sec, (long)tv.tv_usec);
+}
+
+void tr2_tbuf_utc_time(struct tr2_tbuf *tb)
+{
+       struct timeval tv;
+       struct tm tm;
+       time_t secs;
+
+       gettimeofday(&tv, NULL);
+       secs = tv.tv_sec;
+       gmtime_r(&secs, &tm);
+
+       xsnprintf(tb->buf, sizeof(tb->buf),
+                 "%4d-%02d-%02d %02d:%02d:%02d.%06ld", tm.tm_year + 1900,
+                 tm.tm_mon + 1, tm.tm_mday, tm.tm_hour, tm.tm_min, tm.tm_sec,
+                 (long)tv.tv_usec);
+}
diff --git a/trace2/tr2_tbuf.h b/trace2/tr2_tbuf.h
new file mode 100644 (file)
index 0000000..9cdefa3
--- /dev/null
@@ -0,0 +1,23 @@
+#ifndef TR2_TBUF_H
+#define TR2_TBUF_H
+
+/*
+ * A simple wrapper around a fixed buffer to avoid C syntax
+ * quirks and the need to pass around an additional size_t
+ * argument.
+ */
+struct tr2_tbuf {
+       char buf[32];
+};
+
+/*
+ * Fill buffer with formatted local time string.
+ */
+void tr2_tbuf_local_time(struct tr2_tbuf *tb);
+
+/*
+ * Fill buffer with formatted UTC time string.
+ */
+void tr2_tbuf_utc_time(struct tr2_tbuf *tb);
+
+#endif /* TR2_TBUF_H */
diff --git a/trace2/tr2_tgt.h b/trace2/tr2_tgt.h
new file mode 100644 (file)
index 0000000..297bb8f
--- /dev/null
@@ -0,0 +1,133 @@
+#ifndef TR2_TGT_H
+#define TR2_TGT_H
+
+struct child_process;
+struct repository;
+struct json_writer;
+
+/*
+ * Function prototypes for a TRACE2 "target" vtable.
+ */
+
+typedef int(tr2_tgt_init_t)(void);
+typedef void(tr2_tgt_term_t)(void);
+
+typedef void(tr2_tgt_evt_version_fl_t)(const char *file, int line);
+
+typedef void(tr2_tgt_evt_start_fl_t)(const char *file, int line,
+                                    const char **argv);
+typedef void(tr2_tgt_evt_exit_fl_t)(const char *file, int line,
+                                   uint64_t us_elapsed_absolute, int code);
+typedef void(tr2_tgt_evt_signal_t)(uint64_t us_elapsed_absolute, int signo);
+typedef void(tr2_tgt_evt_atexit_t)(uint64_t us_elapsed_absolute, int code);
+
+typedef void(tr2_tgt_evt_error_va_fl_t)(const char *file, int line,
+                                       const char *fmt, va_list ap);
+
+typedef void(tr2_tgt_evt_command_path_fl_t)(const char *file, int line,
+                                           const char *command_path);
+typedef void(tr2_tgt_evt_command_name_fl_t)(const char *file, int line,
+                                           const char *name,
+                                           const char *hierarchy);
+typedef void(tr2_tgt_evt_command_mode_fl_t)(const char *file, int line,
+                                           const char *mode);
+
+typedef void(tr2_tgt_evt_alias_fl_t)(const char *file, int line,
+                                    const char *alias, const char **argv);
+
+typedef void(tr2_tgt_evt_child_start_fl_t)(const char *file, int line,
+                                          uint64_t us_elapsed_absolute,
+                                          const struct child_process *cmd);
+typedef void(tr2_tgt_evt_child_exit_fl_t)(const char *file, int line,
+                                         uint64_t us_elapsed_absolute, int cid,
+                                         int pid, int code,
+                                         uint64_t us_elapsed_child);
+
+typedef void(tr2_tgt_evt_thread_start_fl_t)(const char *file, int line,
+                                           uint64_t us_elapsed_absolute);
+typedef void(tr2_tgt_evt_thread_exit_fl_t)(const char *file, int line,
+                                          uint64_t us_elapsed_absolute,
+                                          uint64_t us_elapsed_thread);
+
+typedef void(tr2_tgt_evt_exec_fl_t)(const char *file, int line,
+                                   uint64_t us_elapsed_absolute, int exec_id,
+                                   const char *exe, const char **argv);
+typedef void(tr2_tgt_evt_exec_result_fl_t)(const char *file, int line,
+                                          uint64_t us_elapsed_absolute,
+                                          int exec_id, int code);
+
+typedef void(tr2_tgt_evt_param_fl_t)(const char *file, int line,
+                                    const char *param, const char *value);
+
+typedef void(tr2_tgt_evt_repo_fl_t)(const char *file, int line,
+                                   const struct repository *repo);
+
+typedef void(tr2_tgt_evt_region_enter_printf_va_fl_t)(
+       const char *file, int line, uint64_t us_elapsed_absolute,
+       const char *category, const char *label, const struct repository *repo,
+       const char *fmt, va_list ap);
+typedef void(tr2_tgt_evt_region_leave_printf_va_fl_t)(
+       const char *file, int line, uint64_t us_elapsed_absolute,
+       uint64_t us_elapsed_region, const char *category, const char *label,
+       const struct repository *repo, const char *fmt, va_list ap);
+
+typedef void(tr2_tgt_evt_data_fl_t)(const char *file, int line,
+                                   uint64_t us_elapsed_absolute,
+                                   uint64_t us_elapsed_region,
+                                   const char *category,
+                                   const struct repository *repo,
+                                   const char *key, const char *value);
+typedef void(tr2_tgt_evt_data_json_fl_t)(const char *file, int line,
+                                        uint64_t us_elapsed_absolute,
+                                        uint64_t us_elapsed_region,
+                                        const char *category,
+                                        const struct repository *repo,
+                                        const char *key,
+                                        const struct json_writer *value);
+
+typedef void(tr2_tgt_evt_printf_va_fl_t)(const char *file, int line,
+                                        uint64_t us_elapsed_absolute,
+                                        const char *fmt, va_list ap);
+
+/*
+ * "vtable" for a TRACE2 target.  Use NULL if a target does not want
+ * to emit that message.
+ */
+/* clang-format off */
+struct tr2_tgt {
+       struct tr2_dst                          *pdst;
+
+       tr2_tgt_init_t                          *pfn_init;
+       tr2_tgt_term_t                          *pfn_term;
+
+       tr2_tgt_evt_version_fl_t                *pfn_version_fl;
+       tr2_tgt_evt_start_fl_t                  *pfn_start_fl;
+       tr2_tgt_evt_exit_fl_t                   *pfn_exit_fl;
+       tr2_tgt_evt_signal_t                    *pfn_signal;
+       tr2_tgt_evt_atexit_t                    *pfn_atexit;
+       tr2_tgt_evt_error_va_fl_t               *pfn_error_va_fl;
+       tr2_tgt_evt_command_path_fl_t           *pfn_command_path_fl;
+       tr2_tgt_evt_command_name_fl_t           *pfn_command_name_fl;
+       tr2_tgt_evt_command_mode_fl_t           *pfn_command_mode_fl;
+       tr2_tgt_evt_alias_fl_t                  *pfn_alias_fl;
+       tr2_tgt_evt_child_start_fl_t            *pfn_child_start_fl;
+       tr2_tgt_evt_child_exit_fl_t             *pfn_child_exit_fl;
+       tr2_tgt_evt_thread_start_fl_t           *pfn_thread_start_fl;
+       tr2_tgt_evt_thread_exit_fl_t            *pfn_thread_exit_fl;
+       tr2_tgt_evt_exec_fl_t                   *pfn_exec_fl;
+       tr2_tgt_evt_exec_result_fl_t            *pfn_exec_result_fl;
+       tr2_tgt_evt_param_fl_t                  *pfn_param_fl;
+       tr2_tgt_evt_repo_fl_t                   *pfn_repo_fl;
+       tr2_tgt_evt_region_enter_printf_va_fl_t *pfn_region_enter_printf_va_fl;
+       tr2_tgt_evt_region_leave_printf_va_fl_t *pfn_region_leave_printf_va_fl;
+       tr2_tgt_evt_data_fl_t                   *pfn_data_fl;
+       tr2_tgt_evt_data_json_fl_t              *pfn_data_json_fl;
+       tr2_tgt_evt_printf_va_fl_t              *pfn_printf_va_fl;
+};
+/* clang-format on */
+
+extern struct tr2_tgt tr2_tgt_event;
+extern struct tr2_tgt tr2_tgt_normal;
+extern struct tr2_tgt tr2_tgt_perf;
+
+#endif /* TR2_TGT_H */
diff --git a/trace2/tr2_tgt_event.c b/trace2/tr2_tgt_event.c
new file mode 100644 (file)
index 0000000..107cb53
--- /dev/null
@@ -0,0 +1,588 @@
+#include "cache.h"
+#include "config.h"
+#include "json-writer.h"
+#include "run-command.h"
+#include "version.h"
+#include "trace2/tr2_dst.h"
+#include "trace2/tr2_tbuf.h"
+#include "trace2/tr2_sid.h"
+#include "trace2/tr2_tgt.h"
+#include "trace2/tr2_tls.h"
+
+static struct tr2_dst tr2dst_event = { "GIT_TR2_EVENT", 0, 0, 0 };
+
+/*
+ * The version number of the JSON data generated by the EVENT target
+ * in this source file.  Update this if you make a significant change
+ * to the JSON fields or message structure.  You probably do not need
+ * to update this if you just add another call to one of the existing
+ * TRACE2 API methods.
+ */
+#define TR2_EVENT_VERSION "1"
+
+/*
+ * Region nesting limit for messages written to the event target.
+ *
+ * The "region_enter" and "region_leave" messages (especially recursive
+ * messages such as those produced while diving the worktree or index)
+ * are primarily intended for the performance target during debugging.
+ *
+ * Some of the outer-most messages, however, may be of interest to the
+ * event target.  Set this environment variable to a larger integer for
+ * more detail in the event target.
+ */
+#define TR2_ENVVAR_EVENT_NESTING "GIT_TR2_EVENT_NESTING"
+static int tr2env_event_nesting_wanted = 2;
+
+/*
+ * Set this environment variable to true to omit the <time>, <file>, and
+ * <line> fields from most events.
+ */
+#define TR2_ENVVAR_EVENT_BRIEF "GIT_TR2_EVENT_BRIEF"
+static int tr2env_event_brief;
+
+static int fn_init(void)
+{
+       int want = tr2_dst_trace_want(&tr2dst_event);
+       int want_nesting;
+       int want_brief;
+       char *nesting;
+       char *brief;
+
+       if (!want)
+               return want;
+
+       nesting = getenv(TR2_ENVVAR_EVENT_NESTING);
+       if (nesting && ((want_nesting = atoi(nesting)) > 0))
+               tr2env_event_nesting_wanted = want_nesting;
+
+       brief = getenv(TR2_ENVVAR_EVENT_BRIEF);
+       if (brief && ((want_brief = atoi(brief)) > 0))
+               tr2env_event_brief = want_brief;
+
+       return want;
+}
+
+static void fn_term(void)
+{
+       tr2_dst_trace_disable(&tr2dst_event);
+}
+
+/*
+ * Append common key-value pairs to the currently open JSON object.
+ *     "event:"<event_name>"
+ *      "sid":"<sid>"
+ *   "thread":"<thread_name>"
+ *     "time":"<time>"
+ *     "file":"<filename>"
+ *     "line":<line_number>
+ *     "repo":<repo_id>
+ */
+static void event_fmt_prepare(const char *event_name, const char *file,
+                             int line, const struct repository *repo,
+                             struct json_writer *jw)
+{
+       struct tr2tls_thread_ctx *ctx = tr2tls_get_self();
+       struct tr2_tbuf tb_now;
+
+       jw_object_string(jw, "event", event_name);
+       jw_object_string(jw, "sid", tr2_sid_get());
+       jw_object_string(jw, "thread", ctx->thread_name.buf);
+
+       /*
+        * In brief mode, only emit <time> on these 2 event types.
+        */
+       if (!tr2env_event_brief || !strcmp(event_name, "version") ||
+           !strcmp(event_name, "atexit")) {
+               tr2_tbuf_utc_time(&tb_now);
+               jw_object_string(jw, "time", tb_now.buf);
+       }
+
+       if (!tr2env_event_brief && file && *file) {
+               jw_object_string(jw, "file", file);
+               jw_object_intmax(jw, "line", line);
+       }
+
+       if (repo)
+               jw_object_intmax(jw, "repo", repo->trace2_repo_id);
+}
+
+static void fn_version_fl(const char *file, int line)
+{
+       const char *event_name = "version";
+       struct json_writer jw = JSON_WRITER_INIT;
+
+       jw_object_begin(&jw, 0);
+       event_fmt_prepare(event_name, file, line, NULL, &jw);
+       jw_object_string(&jw, "evt", TR2_EVENT_VERSION);
+       jw_object_string(&jw, "exe", git_version_string);
+       jw_end(&jw);
+
+       tr2_dst_write_line(&tr2dst_event, &jw.json);
+       jw_release(&jw);
+}
+
+static void fn_start_fl(const char *file, int line, const char **argv)
+{
+       const char *event_name = "start";
+       struct json_writer jw = JSON_WRITER_INIT;
+
+       jw_object_begin(&jw, 0);
+       event_fmt_prepare(event_name, file, line, NULL, &jw);
+       jw_object_inline_begin_array(&jw, "argv");
+       jw_array_argv(&jw, argv);
+       jw_end(&jw);
+       jw_end(&jw);
+
+       tr2_dst_write_line(&tr2dst_event, &jw.json);
+       jw_release(&jw);
+}
+
+static void fn_exit_fl(const char *file, int line, uint64_t us_elapsed_absolute,
+                      int code)
+{
+       const char *event_name = "exit";
+       struct json_writer jw = JSON_WRITER_INIT;
+       double t_abs = (double)us_elapsed_absolute / 1000000.0;
+
+       jw_object_begin(&jw, 0);
+       event_fmt_prepare(event_name, file, line, NULL, &jw);
+       jw_object_double(&jw, "t_abs", 6, t_abs);
+       jw_object_intmax(&jw, "code", code);
+       jw_end(&jw);
+
+       tr2_dst_write_line(&tr2dst_event, &jw.json);
+       jw_release(&jw);
+}
+
+static void fn_signal(uint64_t us_elapsed_absolute, int signo)
+{
+       const char *event_name = "signal";
+       struct json_writer jw = JSON_WRITER_INIT;
+       double t_abs = (double)us_elapsed_absolute / 1000000.0;
+
+       jw_object_begin(&jw, 0);
+       event_fmt_prepare(event_name, __FILE__, __LINE__, NULL, &jw);
+       jw_object_double(&jw, "t_abs", 6, t_abs);
+       jw_object_intmax(&jw, "signo", signo);
+       jw_end(&jw);
+
+       tr2_dst_write_line(&tr2dst_event, &jw.json);
+       jw_release(&jw);
+}
+
+static void fn_atexit(uint64_t us_elapsed_absolute, int code)
+{
+       const char *event_name = "atexit";
+       struct json_writer jw = JSON_WRITER_INIT;
+       double t_abs = (double)us_elapsed_absolute / 1000000.0;
+
+       jw_object_begin(&jw, 0);
+       event_fmt_prepare(event_name, __FILE__, __LINE__, NULL, &jw);
+       jw_object_double(&jw, "t_abs", 6, t_abs);
+       jw_object_intmax(&jw, "code", code);
+       jw_end(&jw);
+
+       tr2_dst_write_line(&tr2dst_event, &jw.json);
+       jw_release(&jw);
+}
+
+static void maybe_add_string_va(struct json_writer *jw, const char *field_name,
+                               const char *fmt, va_list ap)
+{
+       if (fmt && *fmt && ap) {
+               va_list copy_ap;
+               struct strbuf buf = STRBUF_INIT;
+
+               va_copy(copy_ap, ap);
+               strbuf_vaddf(&buf, fmt, copy_ap);
+               va_end(copy_ap);
+
+               jw_object_string(jw, field_name, buf.buf);
+               strbuf_release(&buf);
+               return;
+       }
+
+       if (fmt && *fmt) {
+               jw_object_string(jw, field_name, fmt);
+               return;
+       }
+}
+
+static void fn_error_va_fl(const char *file, int line, const char *fmt,
+                          va_list ap)
+{
+       const char *event_name = "error";
+       struct json_writer jw = JSON_WRITER_INIT;
+
+       jw_object_begin(&jw, 0);
+       event_fmt_prepare(event_name, file, line, NULL, &jw);
+       maybe_add_string_va(&jw, "msg", fmt, ap);
+       /*
+        * Also emit the format string as a field in case
+        * post-processors want to aggregate common error
+        * messages by type without argument fields (such
+        * as pathnames or branch names) cluttering it up.
+        */
+       if (fmt && *fmt)
+               jw_object_string(&jw, "fmt", fmt);
+       jw_end(&jw);
+
+       tr2_dst_write_line(&tr2dst_event, &jw.json);
+       jw_release(&jw);
+}
+
+static void fn_command_path_fl(const char *file, int line, const char *pathname)
+{
+       const char *event_name = "cmd_path";
+       struct json_writer jw = JSON_WRITER_INIT;
+
+       jw_object_begin(&jw, 0);
+       event_fmt_prepare(event_name, file, line, NULL, &jw);
+       jw_object_string(&jw, "path", pathname);
+       jw_end(&jw);
+
+       tr2_dst_write_line(&tr2dst_event, &jw.json);
+       jw_release(&jw);
+}
+
+static void fn_command_name_fl(const char *file, int line, const char *name,
+                              const char *hierarchy)
+{
+       const char *event_name = "cmd_name";
+       struct json_writer jw = JSON_WRITER_INIT;
+
+       jw_object_begin(&jw, 0);
+       event_fmt_prepare(event_name, file, line, NULL, &jw);
+       jw_object_string(&jw, "name", name);
+       if (hierarchy && *hierarchy)
+               jw_object_string(&jw, "hierarchy", hierarchy);
+       jw_end(&jw);
+
+       tr2_dst_write_line(&tr2dst_event, &jw.json);
+       jw_release(&jw);
+}
+
+static void fn_command_mode_fl(const char *file, int line, const char *mode)
+{
+       const char *event_name = "cmd_mode";
+       struct json_writer jw = JSON_WRITER_INIT;
+
+       jw_object_begin(&jw, 0);
+       event_fmt_prepare(event_name, file, line, NULL, &jw);
+       jw_object_string(&jw, "name", mode);
+       jw_end(&jw);
+
+       tr2_dst_write_line(&tr2dst_event, &jw.json);
+       jw_release(&jw);
+}
+
+static void fn_alias_fl(const char *file, int line, const char *alias,
+                       const char **argv)
+{
+       const char *event_name = "alias";
+       struct json_writer jw = JSON_WRITER_INIT;
+
+       jw_object_begin(&jw, 0);
+       event_fmt_prepare(event_name, file, line, NULL, &jw);
+       jw_object_string(&jw, "alias", alias);
+       jw_object_inline_begin_array(&jw, "argv");
+       jw_array_argv(&jw, argv);
+       jw_end(&jw);
+       jw_end(&jw);
+
+       tr2_dst_write_line(&tr2dst_event, &jw.json);
+       jw_release(&jw);
+}
+
+static void fn_child_start_fl(const char *file, int line,
+                             uint64_t us_elapsed_absolute,
+                             const struct child_process *cmd)
+{
+       const char *event_name = "child_start";
+       struct json_writer jw = JSON_WRITER_INIT;
+
+       jw_object_begin(&jw, 0);
+       event_fmt_prepare(event_name, file, line, NULL, &jw);
+       jw_object_intmax(&jw, "child_id", cmd->trace2_child_id);
+       if (cmd->trace2_hook_name) {
+               jw_object_string(&jw, "child_class", "hook");
+               jw_object_string(&jw, "hook_name", cmd->trace2_hook_name);
+       } else {
+               const char *child_class =
+                       cmd->trace2_child_class ? cmd->trace2_child_class : "?";
+               jw_object_string(&jw, "child_class", child_class);
+       }
+       if (cmd->dir)
+               jw_object_string(&jw, "cd", cmd->dir);
+       jw_object_bool(&jw, "use_shell", cmd->use_shell);
+       jw_object_inline_begin_array(&jw, "argv");
+       if (cmd->git_cmd)
+               jw_array_string(&jw, "git");
+       jw_array_argv(&jw, cmd->argv);
+       jw_end(&jw);
+       jw_end(&jw);
+
+       tr2_dst_write_line(&tr2dst_event, &jw.json);
+       jw_release(&jw);
+}
+
+static void fn_child_exit_fl(const char *file, int line,
+                            uint64_t us_elapsed_absolute, int cid, int pid,
+                            int code, uint64_t us_elapsed_child)
+{
+       const char *event_name = "child_exit";
+       struct json_writer jw = JSON_WRITER_INIT;
+       double t_rel = (double)us_elapsed_child / 1000000.0;
+
+       jw_object_begin(&jw, 0);
+       event_fmt_prepare(event_name, file, line, NULL, &jw);
+       jw_object_intmax(&jw, "child_id", cid);
+       jw_object_intmax(&jw, "pid", pid);
+       jw_object_intmax(&jw, "code", code);
+       jw_object_double(&jw, "t_rel", 6, t_rel);
+       jw_end(&jw);
+
+       tr2_dst_write_line(&tr2dst_event, &jw.json);
+
+       jw_release(&jw);
+}
+
+static void fn_thread_start_fl(const char *file, int line,
+                              uint64_t us_elapsed_absolute)
+{
+       const char *event_name = "thread_start";
+       struct json_writer jw = JSON_WRITER_INIT;
+
+       jw_object_begin(&jw, 0);
+       event_fmt_prepare(event_name, file, line, NULL, &jw);
+       jw_end(&jw);
+
+       tr2_dst_write_line(&tr2dst_event, &jw.json);
+       jw_release(&jw);
+}
+
+static void fn_thread_exit_fl(const char *file, int line,
+                             uint64_t us_elapsed_absolute,
+                             uint64_t us_elapsed_thread)
+{
+       const char *event_name = "thread_exit";
+       struct json_writer jw = JSON_WRITER_INIT;
+       double t_rel = (double)us_elapsed_thread / 1000000.0;
+
+       jw_object_begin(&jw, 0);
+       event_fmt_prepare(event_name, file, line, NULL, &jw);
+       jw_object_double(&jw, "t_rel", 6, t_rel);
+       jw_end(&jw);
+
+       tr2_dst_write_line(&tr2dst_event, &jw.json);
+       jw_release(&jw);
+}
+
+static void fn_exec_fl(const char *file, int line, uint64_t us_elapsed_absolute,
+                      int exec_id, const char *exe, const char **argv)
+{
+       const char *event_name = "exec";
+       struct json_writer jw = JSON_WRITER_INIT;
+
+       jw_object_begin(&jw, 0);
+       event_fmt_prepare(event_name, file, line, NULL, &jw);
+       jw_object_intmax(&jw, "exec_id", exec_id);
+       if (exe)
+               jw_object_string(&jw, "exe", exe);
+       jw_object_inline_begin_array(&jw, "argv");
+       jw_array_argv(&jw, argv);
+       jw_end(&jw);
+       jw_end(&jw);
+
+       tr2_dst_write_line(&tr2dst_event, &jw.json);
+       jw_release(&jw);
+}
+
+static void fn_exec_result_fl(const char *file, int line,
+                             uint64_t us_elapsed_absolute, int exec_id,
+                             int code)
+{
+       const char *event_name = "exec_result";
+       struct json_writer jw = JSON_WRITER_INIT;
+
+       jw_object_begin(&jw, 0);
+       event_fmt_prepare(event_name, file, line, NULL, &jw);
+       jw_object_intmax(&jw, "exec_id", exec_id);
+       jw_object_intmax(&jw, "code", code);
+       jw_end(&jw);
+
+       tr2_dst_write_line(&tr2dst_event, &jw.json);
+       jw_release(&jw);
+}
+
+static void fn_param_fl(const char *file, int line, const char *param,
+                       const char *value)
+{
+       const char *event_name = "def_param";
+       struct json_writer jw = JSON_WRITER_INIT;
+
+       jw_object_begin(&jw, 0);
+       event_fmt_prepare(event_name, file, line, NULL, &jw);
+       jw_object_string(&jw, "param", param);
+       jw_object_string(&jw, "value", value);
+       jw_end(&jw);
+
+       tr2_dst_write_line(&tr2dst_event, &jw.json);
+       jw_release(&jw);
+}
+
+static void fn_repo_fl(const char *file, int line,
+                      const struct repository *repo)
+{
+       const char *event_name = "def_repo";
+       struct json_writer jw = JSON_WRITER_INIT;
+
+       jw_object_begin(&jw, 0);
+       event_fmt_prepare(event_name, file, line, repo, &jw);
+       jw_object_string(&jw, "worktree", repo->worktree);
+       jw_end(&jw);
+
+       tr2_dst_write_line(&tr2dst_event, &jw.json);
+       jw_release(&jw);
+}
+
+static void fn_region_enter_printf_va_fl(const char *file, int line,
+                                        uint64_t us_elapsed_absolute,
+                                        const char *category,
+                                        const char *label,
+                                        const struct repository *repo,
+                                        const char *fmt, va_list ap)
+{
+       const char *event_name = "region_enter";
+       struct tr2tls_thread_ctx *ctx = tr2tls_get_self();
+       if (ctx->nr_open_regions <= tr2env_event_nesting_wanted) {
+               struct json_writer jw = JSON_WRITER_INIT;
+
+               jw_object_begin(&jw, 0);
+               event_fmt_prepare(event_name, file, line, repo, &jw);
+               jw_object_intmax(&jw, "nesting", ctx->nr_open_regions);
+               if (category)
+                       jw_object_string(&jw, "category", category);
+               if (label)
+                       jw_object_string(&jw, "label", label);
+               maybe_add_string_va(&jw, "msg", fmt, ap);
+               jw_end(&jw);
+
+               tr2_dst_write_line(&tr2dst_event, &jw.json);
+               jw_release(&jw);
+       }
+}
+
+static void fn_region_leave_printf_va_fl(
+       const char *file, int line, uint64_t us_elapsed_absolute,
+       uint64_t us_elapsed_region, const char *category, const char *label,
+       const struct repository *repo, const char *fmt, va_list ap)
+{
+       const char *event_name = "region_leave";
+       struct tr2tls_thread_ctx *ctx = tr2tls_get_self();
+       if (ctx->nr_open_regions <= tr2env_event_nesting_wanted) {
+               struct json_writer jw = JSON_WRITER_INIT;
+               double t_rel = (double)us_elapsed_region / 1000000.0;
+
+               jw_object_begin(&jw, 0);
+               event_fmt_prepare(event_name, file, line, repo, &jw);
+               jw_object_double(&jw, "t_rel", 6, t_rel);
+               jw_object_intmax(&jw, "nesting", ctx->nr_open_regions);
+               if (category)
+                       jw_object_string(&jw, "category", category);
+               if (label)
+                       jw_object_string(&jw, "label", label);
+               maybe_add_string_va(&jw, "msg", fmt, ap);
+               jw_end(&jw);
+
+               tr2_dst_write_line(&tr2dst_event, &jw.json);
+               jw_release(&jw);
+       }
+}
+
+static void fn_data_fl(const char *file, int line, uint64_t us_elapsed_absolute,
+                      uint64_t us_elapsed_region, const char *category,
+                      const struct repository *repo, const char *key,
+                      const char *value)
+{
+       const char *event_name = "data";
+       struct tr2tls_thread_ctx *ctx = tr2tls_get_self();
+       if (ctx->nr_open_regions <= tr2env_event_nesting_wanted) {
+               struct json_writer jw = JSON_WRITER_INIT;
+               double t_abs = (double)us_elapsed_absolute / 1000000.0;
+               double t_rel = (double)us_elapsed_region / 1000000.0;
+
+               jw_object_begin(&jw, 0);
+               event_fmt_prepare(event_name, file, line, repo, &jw);
+               jw_object_double(&jw, "t_abs", 6, t_abs);
+               jw_object_double(&jw, "t_rel", 6, t_rel);
+               jw_object_intmax(&jw, "nesting", ctx->nr_open_regions);
+               jw_object_string(&jw, "category", category);
+               jw_object_string(&jw, "key", key);
+               jw_object_string(&jw, "value", value);
+               jw_end(&jw);
+
+               tr2_dst_write_line(&tr2dst_event, &jw.json);
+               jw_release(&jw);
+       }
+}
+
+static void fn_data_json_fl(const char *file, int line,
+                           uint64_t us_elapsed_absolute,
+                           uint64_t us_elapsed_region, const char *category,
+                           const struct repository *repo, const char *key,
+                           const struct json_writer *value)
+{
+       const char *event_name = "data_json";
+       struct tr2tls_thread_ctx *ctx = tr2tls_get_self();
+       if (ctx->nr_open_regions <= tr2env_event_nesting_wanted) {
+               struct json_writer jw = JSON_WRITER_INIT;
+               double t_abs = (double)us_elapsed_absolute / 1000000.0;
+               double t_rel = (double)us_elapsed_region / 1000000.0;
+
+               jw_object_begin(&jw, 0);
+               event_fmt_prepare(event_name, file, line, repo, &jw);
+               jw_object_double(&jw, "t_abs", 6, t_abs);
+               jw_object_double(&jw, "t_rel", 6, t_rel);
+               jw_object_intmax(&jw, "nesting", ctx->nr_open_regions);
+               jw_object_string(&jw, "category", category);
+               jw_object_string(&jw, "key", key);
+               jw_object_sub_jw(&jw, "value", value);
+               jw_end(&jw);
+
+               tr2_dst_write_line(&tr2dst_event, &jw.json);
+               jw_release(&jw);
+       }
+}
+
+struct tr2_tgt tr2_tgt_event = {
+       &tr2dst_event,
+
+       fn_init,
+       fn_term,
+
+       fn_version_fl,
+       fn_start_fl,
+       fn_exit_fl,
+       fn_signal,
+       fn_atexit,
+       fn_error_va_fl,
+       fn_command_path_fl,
+       fn_command_name_fl,
+       fn_command_mode_fl,
+       fn_alias_fl,
+       fn_child_start_fl,
+       fn_child_exit_fl,
+       fn_thread_start_fl,
+       fn_thread_exit_fl,
+       fn_exec_fl,
+       fn_exec_result_fl,
+       fn_param_fl,
+       fn_repo_fl,
+       fn_region_enter_printf_va_fl,
+       fn_region_leave_printf_va_fl,
+       fn_data_fl,
+       fn_data_json_fl,
+       NULL, /* printf */
+};
diff --git a/trace2/tr2_tgt_normal.c b/trace2/tr2_tgt_normal.c
new file mode 100644 (file)
index 0000000..547183d
--- /dev/null
@@ -0,0 +1,323 @@
+#include "cache.h"
+#include "config.h"
+#include "run-command.h"
+#include "quote.h"
+#include "version.h"
+#include "trace2/tr2_dst.h"
+#include "trace2/tr2_tbuf.h"
+#include "trace2/tr2_tgt.h"
+#include "trace2/tr2_tls.h"
+
+static struct tr2_dst tr2dst_normal = { "GIT_TR2", 0, 0, 0 };
+
+/*
+ * Set this environment variable to true to omit the "<time> <file>:<line>"
+ * fields from each line written to the builtin normal target.
+ *
+ * Unit tests may want to use this to help with testing.
+ */
+#define TR2_ENVVAR_NORMAL_BRIEF "GIT_TR2_BRIEF"
+static int tr2env_normal_brief;
+
+#define TR2FMT_NORMAL_FL_WIDTH (50)
+
+static int fn_init(void)
+{
+       int want = tr2_dst_trace_want(&tr2dst_normal);
+       int want_brief;
+       char *brief;
+
+       if (!want)
+               return want;
+
+       brief = getenv(TR2_ENVVAR_NORMAL_BRIEF);
+       if (brief && *brief &&
+           ((want_brief = git_parse_maybe_bool(brief)) != -1))
+               tr2env_normal_brief = want_brief;
+
+       return want;
+}
+
+static void fn_term(void)
+{
+       tr2_dst_trace_disable(&tr2dst_normal);
+}
+
+static void normal_fmt_prepare(const char *file, int line, struct strbuf *buf)
+{
+       strbuf_setlen(buf, 0);
+
+       if (!tr2env_normal_brief) {
+               struct tr2_tbuf tb_now;
+
+               tr2_tbuf_local_time(&tb_now);
+               strbuf_addstr(buf, tb_now.buf);
+               strbuf_addch(buf, ' ');
+
+               if (file && *file)
+                       strbuf_addf(buf, "%s:%d ", file, line);
+               while (buf->len < TR2FMT_NORMAL_FL_WIDTH)
+                       strbuf_addch(buf, ' ');
+       }
+}
+
+static void normal_io_write_fl(const char *file, int line,
+                              const struct strbuf *buf_payload)
+{
+       struct strbuf buf_line = STRBUF_INIT;
+
+       normal_fmt_prepare(file, line, &buf_line);
+       strbuf_addbuf(&buf_line, buf_payload);
+       tr2_dst_write_line(&tr2dst_normal, &buf_line);
+       strbuf_release(&buf_line);
+}
+
+static void fn_version_fl(const char *file, int line)
+{
+       struct strbuf buf_payload = STRBUF_INIT;
+
+       strbuf_addf(&buf_payload, "version %s", git_version_string);
+       normal_io_write_fl(file, line, &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void fn_start_fl(const char *file, int line, const char **argv)
+{
+       struct strbuf buf_payload = STRBUF_INIT;
+
+       strbuf_addstr(&buf_payload, "start ");
+       sq_quote_argv_pretty(&buf_payload, argv);
+       normal_io_write_fl(file, line, &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void fn_exit_fl(const char *file, int line, uint64_t us_elapsed_absolute,
+                      int code)
+{
+       struct strbuf buf_payload = STRBUF_INIT;
+       double elapsed = (double)us_elapsed_absolute / 1000000.0;
+
+       strbuf_addf(&buf_payload, "exit elapsed:%.6f code:%d", elapsed, code);
+       normal_io_write_fl(file, line, &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void fn_signal(uint64_t us_elapsed_absolute, int signo)
+{
+       struct strbuf buf_payload = STRBUF_INIT;
+       double elapsed = (double)us_elapsed_absolute / 1000000.0;
+
+       strbuf_addf(&buf_payload, "signal elapsed:%.6f code:%d", elapsed,
+                   signo);
+       normal_io_write_fl(__FILE__, __LINE__, &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void fn_atexit(uint64_t us_elapsed_absolute, int code)
+{
+       struct strbuf buf_payload = STRBUF_INIT;
+       double elapsed = (double)us_elapsed_absolute / 1000000.0;
+
+       strbuf_addf(&buf_payload, "atexit elapsed:%.6f code:%d", elapsed, code);
+       normal_io_write_fl(__FILE__, __LINE__, &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void maybe_append_string_va(struct strbuf *buf, const char *fmt,
+                                  va_list ap)
+{
+       if (fmt && *fmt && ap) {
+               va_list copy_ap;
+
+               va_copy(copy_ap, ap);
+               strbuf_vaddf(buf, fmt, copy_ap);
+               va_end(copy_ap);
+               return;
+       }
+
+       if (fmt && *fmt) {
+               strbuf_addstr(buf, fmt);
+               return;
+       }
+}
+
+static void fn_error_va_fl(const char *file, int line, const char *fmt,
+                          va_list ap)
+{
+       struct strbuf buf_payload = STRBUF_INIT;
+
+       strbuf_addstr(&buf_payload, "error ");
+       maybe_append_string_va(&buf_payload, fmt, ap);
+       normal_io_write_fl(file, line, &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void fn_command_path_fl(const char *file, int line, const char *pathname)
+{
+       struct strbuf buf_payload = STRBUF_INIT;
+
+       strbuf_addf(&buf_payload, "cmd_path %s", pathname);
+       normal_io_write_fl(file, line, &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void fn_command_name_fl(const char *file, int line, const char *name,
+                              const char *hierarchy)
+{
+       struct strbuf buf_payload = STRBUF_INIT;
+
+       strbuf_addf(&buf_payload, "cmd_name %s", name);
+       if (hierarchy && *hierarchy)
+               strbuf_addf(&buf_payload, " (%s)", hierarchy);
+       normal_io_write_fl(file, line, &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void fn_command_mode_fl(const char *file, int line, const char *mode)
+{
+       struct strbuf buf_payload = STRBUF_INIT;
+
+       strbuf_addf(&buf_payload, "cmd_mode %s", mode);
+       normal_io_write_fl(file, line, &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void fn_alias_fl(const char *file, int line, const char *alias,
+                       const char **argv)
+{
+       struct strbuf buf_payload = STRBUF_INIT;
+
+       strbuf_addf(&buf_payload, "alias %s ->", alias);
+       sq_quote_argv_pretty(&buf_payload, argv);
+       normal_io_write_fl(file, line, &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void fn_child_start_fl(const char *file, int line,
+                             uint64_t us_elapsed_absolute,
+                             const struct child_process *cmd)
+{
+       struct strbuf buf_payload = STRBUF_INIT;
+
+       strbuf_addf(&buf_payload, "child_start[%d] ", cmd->trace2_child_id);
+
+       if (cmd->dir) {
+               strbuf_addstr(&buf_payload, " cd");
+               sq_quote_buf_pretty(&buf_payload, cmd->dir);
+               strbuf_addstr(&buf_payload, "; ");
+       }
+
+       /*
+        * TODO if (cmd->env) { Consider dumping changes to environment. }
+        * See trace_add_env() in run-command.c as used by original trace.c
+        */
+
+       if (cmd->git_cmd)
+               strbuf_addstr(&buf_payload, "git");
+       sq_quote_argv_pretty(&buf_payload, cmd->argv);
+
+       normal_io_write_fl(file, line, &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void fn_child_exit_fl(const char *file, int line,
+                            uint64_t us_elapsed_absolute, int cid, int pid,
+                            int code, uint64_t us_elapsed_child)
+{
+       struct strbuf buf_payload = STRBUF_INIT;
+       double elapsed = (double)us_elapsed_child / 1000000.0;
+
+       strbuf_addf(&buf_payload, "child_exit[%d] pid:%d code:%d elapsed:%.6f",
+                   cid, pid, code, elapsed);
+       normal_io_write_fl(file, line, &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void fn_exec_fl(const char *file, int line, uint64_t us_elapsed_absolute,
+                      int exec_id, const char *exe, const char **argv)
+{
+       struct strbuf buf_payload = STRBUF_INIT;
+
+       strbuf_addf(&buf_payload, "exec[%d] ", exec_id);
+       if (exe)
+               strbuf_addstr(&buf_payload, exe);
+       sq_quote_argv_pretty(&buf_payload, argv);
+       normal_io_write_fl(file, line, &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void fn_exec_result_fl(const char *file, int line,
+                             uint64_t us_elapsed_absolute, int exec_id,
+                             int code)
+{
+       struct strbuf buf_payload = STRBUF_INIT;
+
+       strbuf_addf(&buf_payload, "exec_result[%d] code:%d", exec_id, code);
+       if (code > 0)
+               strbuf_addf(&buf_payload, " err:%s", strerror(code));
+       normal_io_write_fl(file, line, &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void fn_param_fl(const char *file, int line, const char *param,
+                       const char *value)
+{
+       struct strbuf buf_payload = STRBUF_INIT;
+
+       strbuf_addf(&buf_payload, "def_param %s=%s", param, value);
+       normal_io_write_fl(file, line, &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void fn_repo_fl(const char *file, int line,
+                      const struct repository *repo)
+{
+       struct strbuf buf_payload = STRBUF_INIT;
+
+       strbuf_addstr(&buf_payload, "worktree ");
+       sq_quote_buf_pretty(&buf_payload, repo->worktree);
+       normal_io_write_fl(file, line, &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void fn_printf_va_fl(const char *file, int line,
+                           uint64_t us_elapsed_absolute, const char *fmt,
+                           va_list ap)
+{
+       struct strbuf buf_payload = STRBUF_INIT;
+
+       maybe_append_string_va(&buf_payload, fmt, ap);
+       normal_io_write_fl(file, line, &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+struct tr2_tgt tr2_tgt_normal = {
+       &tr2dst_normal,
+
+       fn_init,
+       fn_term,
+
+       fn_version_fl,
+       fn_start_fl,
+       fn_exit_fl,
+       fn_signal,
+       fn_atexit,
+       fn_error_va_fl,
+       fn_command_path_fl,
+       fn_command_name_fl,
+       fn_command_mode_fl,
+       fn_alias_fl,
+       fn_child_start_fl,
+       fn_child_exit_fl,
+       NULL, /* thread_start */
+       NULL, /* thread_exit */
+       fn_exec_fl,
+       fn_exec_result_fl,
+       fn_param_fl,
+       fn_repo_fl,
+       NULL, /* region_enter */
+       NULL, /* region_leave */
+       NULL, /* data */
+       NULL, /* data_json */
+       fn_printf_va_fl,
+};
diff --git a/trace2/tr2_tgt_perf.c b/trace2/tr2_tgt_perf.c
new file mode 100644 (file)
index 0000000..f0746fc
--- /dev/null
@@ -0,0 +1,534 @@
+#include "cache.h"
+#include "config.h"
+#include "run-command.h"
+#include "quote.h"
+#include "version.h"
+#include "json-writer.h"
+#include "trace2/tr2_dst.h"
+#include "trace2/tr2_sid.h"
+#include "trace2/tr2_tbuf.h"
+#include "trace2/tr2_tgt.h"
+#include "trace2/tr2_tls.h"
+
+static struct tr2_dst tr2dst_perf = { "GIT_TR2_PERF", 0, 0, 0 };
+
+/*
+ * Set this environment variable to true to omit the "<time> <file>:<line>"
+ * fields from each line written to the builtin performance target.
+ *
+ * Unit tests may want to use this to help with testing.
+ */
+#define TR2_ENVVAR_PERF_BRIEF "GIT_TR2_PERF_BRIEF"
+static int tr2env_perf_brief;
+
+#define TR2FMT_PERF_FL_WIDTH (50)
+#define TR2FMT_PERF_MAX_EVENT_NAME (12)
+#define TR2FMT_PERF_REPO_WIDTH (4)
+#define TR2FMT_PERF_CATEGORY_WIDTH (10)
+
+#define TR2_DOTS_BUFFER_SIZE (100)
+#define TR2_INDENT (2)
+#define TR2_INDENT_LENGTH(ctx) (((ctx)->nr_open_regions - 1) * TR2_INDENT)
+
+static struct strbuf dots = STRBUF_INIT;
+
+static int fn_init(void)
+{
+       int want = tr2_dst_trace_want(&tr2dst_perf);
+       int want_brief;
+       char *brief;
+
+       if (!want)
+               return want;
+
+       strbuf_addchars(&dots, '.', TR2_DOTS_BUFFER_SIZE);
+
+       brief = getenv(TR2_ENVVAR_PERF_BRIEF);
+       if (brief && *brief &&
+           ((want_brief = git_parse_maybe_bool(brief)) != -1))
+               tr2env_perf_brief = want_brief;
+
+       return want;
+}
+
+static void fn_term(void)
+{
+       tr2_dst_trace_disable(&tr2dst_perf);
+
+       strbuf_release(&dots);
+}
+
+/*
+ * Format trace line prefix in human-readable classic format for
+ * the performance target:
+ *     "[<time> [<file>:<line>] <bar>] <nr_parents> <bar>
+ *         <thread_name> <bar> <event_name> <bar> [<repo>] <bar>
+ *         [<elapsed_absolute>] [<elapsed_relative>] <bar>
+ *         [<category>] <bar> [<dots>] "
+ */
+static void perf_fmt_prepare(const char *event_name,
+                            struct tr2tls_thread_ctx *ctx, const char *file,
+                            int line, const struct repository *repo,
+                            uint64_t *p_us_elapsed_absolute,
+                            uint64_t *p_us_elapsed_relative,
+                            const char *category, struct strbuf *buf)
+{
+       int len;
+
+       strbuf_setlen(buf, 0);
+
+       if (!tr2env_perf_brief) {
+               struct tr2_tbuf tb_now;
+
+               tr2_tbuf_local_time(&tb_now);
+               strbuf_addstr(buf, tb_now.buf);
+               strbuf_addch(buf, ' ');
+
+               if (file && *file)
+                       strbuf_addf(buf, "%s:%d ", file, line);
+               while (buf->len < TR2FMT_PERF_FL_WIDTH)
+                       strbuf_addch(buf, ' ');
+
+               strbuf_addstr(buf, "| ");
+       }
+
+       strbuf_addf(buf, "d%d | ", tr2_sid_depth());
+       strbuf_addf(buf, "%-*s | %-*s | ", TR2_MAX_THREAD_NAME,
+                   ctx->thread_name.buf, TR2FMT_PERF_MAX_EVENT_NAME,
+                   event_name);
+
+       len = buf->len + TR2FMT_PERF_REPO_WIDTH;
+       if (repo)
+               strbuf_addf(buf, "r%d ", repo->trace2_repo_id);
+       while (buf->len < len)
+               strbuf_addch(buf, ' ');
+       strbuf_addstr(buf, "| ");
+
+       if (p_us_elapsed_absolute)
+               strbuf_addf(buf, "%9.6f | ",
+                           ((double)(*p_us_elapsed_absolute)) / 1000000.0);
+       else
+               strbuf_addf(buf, "%9s | ", " ");
+
+       if (p_us_elapsed_relative)
+               strbuf_addf(buf, "%9.6f | ",
+                           ((double)(*p_us_elapsed_relative)) / 1000000.0);
+       else
+               strbuf_addf(buf, "%9s | ", " ");
+
+       strbuf_addf(buf, "%-*s | ", TR2FMT_PERF_CATEGORY_WIDTH,
+                   (category ? category : ""));
+
+       if (ctx->nr_open_regions > 0) {
+               int len_indent = TR2_INDENT_LENGTH(ctx);
+               while (len_indent > dots.len) {
+                       strbuf_addbuf(buf, &dots);
+                       len_indent -= dots.len;
+               }
+               strbuf_addf(buf, "%.*s", len_indent, dots.buf);
+       }
+}
+
+static void perf_io_write_fl(const char *file, int line, const char *event_name,
+                            const struct repository *repo,
+                            uint64_t *p_us_elapsed_absolute,
+                            uint64_t *p_us_elapsed_relative,
+                            const char *category,
+                            const struct strbuf *buf_payload)
+{
+       struct tr2tls_thread_ctx *ctx = tr2tls_get_self();
+       struct strbuf buf_line = STRBUF_INIT;
+
+       perf_fmt_prepare(event_name, ctx, file, line, repo,
+                        p_us_elapsed_absolute, p_us_elapsed_relative, category,
+                        &buf_line);
+       strbuf_addbuf(&buf_line, buf_payload);
+       tr2_dst_write_line(&tr2dst_perf, &buf_line);
+       strbuf_release(&buf_line);
+}
+
+static void fn_version_fl(const char *file, int line)
+{
+       const char *event_name = "version";
+       struct strbuf buf_payload = STRBUF_INIT;
+
+       strbuf_addstr(&buf_payload, git_version_string);
+
+       perf_io_write_fl(file, line, event_name, NULL, NULL, NULL, NULL,
+                        &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void fn_start_fl(const char *file, int line, const char **argv)
+{
+       const char *event_name = "start";
+       struct strbuf buf_payload = STRBUF_INIT;
+
+       sq_quote_argv_pretty(&buf_payload, argv);
+
+       perf_io_write_fl(file, line, event_name, NULL, NULL, NULL, NULL,
+                        &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void fn_exit_fl(const char *file, int line, uint64_t us_elapsed_absolute,
+                      int code)
+{
+       const char *event_name = "exit";
+       struct strbuf buf_payload = STRBUF_INIT;
+
+       strbuf_addf(&buf_payload, "code:%d", code);
+
+       perf_io_write_fl(file, line, event_name, NULL, &us_elapsed_absolute,
+                        NULL, NULL, &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void fn_signal(uint64_t us_elapsed_absolute, int signo)
+{
+       const char *event_name = "signal";
+       struct strbuf buf_payload = STRBUF_INIT;
+
+       strbuf_addf(&buf_payload, "signo:%d", signo);
+
+       perf_io_write_fl(__FILE__, __LINE__, event_name, NULL,
+                        &us_elapsed_absolute, NULL, NULL, &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void fn_atexit(uint64_t us_elapsed_absolute, int code)
+{
+       const char *event_name = "atexit";
+       struct strbuf buf_payload = STRBUF_INIT;
+
+       strbuf_addf(&buf_payload, "code:%d", code);
+
+       perf_io_write_fl(__FILE__, __LINE__, event_name, NULL,
+                        &us_elapsed_absolute, NULL, NULL, &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void maybe_append_string_va(struct strbuf *buf, const char *fmt,
+                                  va_list ap)
+{
+       if (fmt && *fmt && ap) {
+               va_list copy_ap;
+
+               va_copy(copy_ap, ap);
+               strbuf_vaddf(buf, fmt, copy_ap);
+               va_end(copy_ap);
+               return;
+       }
+
+       if (fmt && *fmt) {
+               strbuf_addstr(buf, fmt);
+               return;
+       }
+}
+
+static void fn_error_va_fl(const char *file, int line, const char *fmt,
+                          va_list ap)
+{
+       const char *event_name = "error";
+       struct strbuf buf_payload = STRBUF_INIT;
+
+       maybe_append_string_va(&buf_payload, fmt, ap);
+
+       perf_io_write_fl(file, line, event_name, NULL, NULL, NULL, NULL,
+                        &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void fn_command_path_fl(const char *file, int line, const char *pathname)
+{
+       const char *event_name = "cmd_path";
+       struct strbuf buf_payload = STRBUF_INIT;
+
+       strbuf_addstr(&buf_payload, pathname);
+
+       perf_io_write_fl(file, line, event_name, NULL, NULL, NULL, NULL,
+                        &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void fn_command_name_fl(const char *file, int line, const char *name,
+                              const char *hierarchy)
+{
+       const char *event_name = "cmd_name";
+       struct strbuf buf_payload = STRBUF_INIT;
+
+       strbuf_addstr(&buf_payload, name);
+       if (hierarchy && *hierarchy)
+               strbuf_addf(&buf_payload, " (%s)", hierarchy);
+
+       perf_io_write_fl(file, line, event_name, NULL, NULL, NULL, NULL,
+                        &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void fn_command_mode_fl(const char *file, int line, const char *mode)
+{
+       const char *event_name = "cmd_mode";
+       struct strbuf buf_payload = STRBUF_INIT;
+
+       strbuf_addstr(&buf_payload, mode);
+
+       perf_io_write_fl(file, line, event_name, NULL, NULL, NULL, NULL,
+                        &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void fn_alias_fl(const char *file, int line, const char *alias,
+                       const char **argv)
+{
+       const char *event_name = "alias";
+       struct strbuf buf_payload = STRBUF_INIT;
+
+       strbuf_addf(&buf_payload, "alias:%s argv:", alias);
+       sq_quote_argv_pretty(&buf_payload, argv);
+
+       perf_io_write_fl(file, line, event_name, NULL, NULL, NULL, NULL,
+                        &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void fn_child_start_fl(const char *file, int line,
+                             uint64_t us_elapsed_absolute,
+                             const struct child_process *cmd)
+{
+       const char *event_name = "child_start";
+       struct strbuf buf_payload = STRBUF_INIT;
+
+       if (cmd->trace2_hook_name) {
+               strbuf_addf(&buf_payload, "[ch%d] class:hook hook:%s",
+                           cmd->trace2_child_id, cmd->trace2_hook_name);
+       } else {
+               const char *child_class =
+                       cmd->trace2_child_class ? cmd->trace2_child_class : "?";
+               strbuf_addf(&buf_payload, "[ch%d] class:%s",
+                           cmd->trace2_child_id, child_class);
+       }
+
+       if (cmd->dir) {
+               strbuf_addstr(&buf_payload, " cd:");
+               sq_quote_buf_pretty(&buf_payload, cmd->dir);
+       }
+
+       strbuf_addstr(&buf_payload, " argv:");
+       if (cmd->git_cmd)
+               strbuf_addstr(&buf_payload, " git");
+       sq_quote_argv_pretty(&buf_payload, cmd->argv);
+
+       perf_io_write_fl(file, line, event_name, NULL, &us_elapsed_absolute,
+                        NULL, NULL, &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void fn_child_exit_fl(const char *file, int line,
+                            uint64_t us_elapsed_absolute, int cid, int pid,
+                            int code, uint64_t us_elapsed_child)
+{
+       const char *event_name = "child_exit";
+       struct strbuf buf_payload = STRBUF_INIT;
+
+       strbuf_addf(&buf_payload, "[ch%d] pid:%d code:%d", cid, pid, code);
+
+       perf_io_write_fl(file, line, event_name, NULL, &us_elapsed_absolute,
+                        &us_elapsed_child, NULL, &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void fn_thread_start_fl(const char *file, int line,
+                              uint64_t us_elapsed_absolute)
+{
+       const char *event_name = "thread_start";
+       struct strbuf buf_payload = STRBUF_INIT;
+
+       perf_io_write_fl(file, line, event_name, NULL, &us_elapsed_absolute,
+                        NULL, NULL, &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void fn_thread_exit_fl(const char *file, int line,
+                             uint64_t us_elapsed_absolute,
+                             uint64_t us_elapsed_thread)
+{
+       const char *event_name = "thread_exit";
+       struct strbuf buf_payload = STRBUF_INIT;
+
+       perf_io_write_fl(file, line, event_name, NULL, &us_elapsed_absolute,
+                        &us_elapsed_thread, NULL, &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void fn_exec_fl(const char *file, int line, uint64_t us_elapsed_absolute,
+                      int exec_id, const char *exe, const char **argv)
+{
+       const char *event_name = "exec";
+       struct strbuf buf_payload = STRBUF_INIT;
+
+       strbuf_addf(&buf_payload, "id:%d ", exec_id);
+       strbuf_addstr(&buf_payload, "argv:");
+       if (exe)
+               strbuf_addf(&buf_payload, " %s", exe);
+       sq_quote_argv_pretty(&buf_payload, argv);
+
+       perf_io_write_fl(file, line, event_name, NULL, &us_elapsed_absolute,
+                        NULL, NULL, &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void fn_exec_result_fl(const char *file, int line,
+                             uint64_t us_elapsed_absolute, int exec_id,
+                             int code)
+{
+       const char *event_name = "exec_result";
+       struct strbuf buf_payload = STRBUF_INIT;
+
+       strbuf_addf(&buf_payload, "id:%d code:%d", exec_id, code);
+       if (code > 0)
+               strbuf_addf(&buf_payload, " err:%s", strerror(code));
+
+       perf_io_write_fl(file, line, event_name, NULL, &us_elapsed_absolute,
+                        NULL, NULL, &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void fn_param_fl(const char *file, int line, const char *param,
+                       const char *value)
+{
+       const char *event_name = "def_param";
+       struct strbuf buf_payload = STRBUF_INIT;
+
+       strbuf_addf(&buf_payload, "%s:%s", param, value);
+
+       perf_io_write_fl(file, line, event_name, NULL, NULL, NULL, NULL,
+                        &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void fn_repo_fl(const char *file, int line,
+                      const struct repository *repo)
+{
+       const char *event_name = "def_repo";
+       struct strbuf buf_payload = STRBUF_INIT;
+
+       strbuf_addstr(&buf_payload, "worktree:");
+       sq_quote_buf_pretty(&buf_payload, repo->worktree);
+
+       perf_io_write_fl(file, line, event_name, repo, NULL, NULL, NULL,
+                        &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void fn_region_enter_printf_va_fl(const char *file, int line,
+                                        uint64_t us_elapsed_absolute,
+                                        const char *category,
+                                        const char *label,
+                                        const struct repository *repo,
+                                        const char *fmt, va_list ap)
+{
+       const char *event_name = "region_enter";
+       struct strbuf buf_payload = STRBUF_INIT;
+
+       if (label)
+               strbuf_addf(&buf_payload, "label:%s ", label);
+       maybe_append_string_va(&buf_payload, fmt, ap);
+
+       perf_io_write_fl(file, line, event_name, repo, &us_elapsed_absolute,
+                        NULL, category, &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void fn_region_leave_printf_va_fl(
+       const char *file, int line, uint64_t us_elapsed_absolute,
+       uint64_t us_elapsed_region, const char *category, const char *label,
+       const struct repository *repo, const char *fmt, va_list ap)
+{
+       const char *event_name = "region_leave";
+       struct strbuf buf_payload = STRBUF_INIT;
+
+       if (label)
+               strbuf_addf(&buf_payload, "label:%s ", label);
+       maybe_append_string_va(&buf_payload, fmt, ap);
+
+       perf_io_write_fl(file, line, event_name, repo, &us_elapsed_absolute,
+                        &us_elapsed_region, category, &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void fn_data_fl(const char *file, int line, uint64_t us_elapsed_absolute,
+                      uint64_t us_elapsed_region, const char *category,
+                      const struct repository *repo, const char *key,
+                      const char *value)
+{
+       const char *event_name = "data";
+       struct strbuf buf_payload = STRBUF_INIT;
+
+       strbuf_addf(&buf_payload, "%s:%s", key, value);
+
+       perf_io_write_fl(file, line, event_name, repo, &us_elapsed_absolute,
+                        &us_elapsed_region, category, &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void fn_data_json_fl(const char *file, int line,
+                           uint64_t us_elapsed_absolute,
+                           uint64_t us_elapsed_region, const char *category,
+                           const struct repository *repo, const char *key,
+                           const struct json_writer *value)
+{
+       const char *event_name = "data_json";
+       struct strbuf buf_payload = STRBUF_INIT;
+
+       strbuf_addf(&buf_payload, "%s:%s", key, value->json.buf);
+
+       perf_io_write_fl(file, line, event_name, repo, &us_elapsed_absolute,
+                        &us_elapsed_region, category, &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+static void fn_printf_va_fl(const char *file, int line,
+                           uint64_t us_elapsed_absolute, const char *fmt,
+                           va_list ap)
+{
+       const char *event_name = "printf";
+       struct strbuf buf_payload = STRBUF_INIT;
+
+       maybe_append_string_va(&buf_payload, fmt, ap);
+
+       perf_io_write_fl(file, line, event_name, NULL, &us_elapsed_absolute,
+                        NULL, NULL, &buf_payload);
+       strbuf_release(&buf_payload);
+}
+
+struct tr2_tgt tr2_tgt_perf = {
+       &tr2dst_perf,
+
+       fn_init,
+       fn_term,
+
+       fn_version_fl,
+       fn_start_fl,
+       fn_exit_fl,
+       fn_signal,
+       fn_atexit,
+       fn_error_va_fl,
+       fn_command_path_fl,
+       fn_command_name_fl,
+       fn_command_mode_fl,
+       fn_alias_fl,
+       fn_child_start_fl,
+       fn_child_exit_fl,
+       fn_thread_start_fl,
+       fn_thread_exit_fl,
+       fn_exec_fl,
+       fn_exec_result_fl,
+       fn_param_fl,
+       fn_repo_fl,
+       fn_region_enter_printf_va_fl,
+       fn_region_leave_printf_va_fl,
+       fn_data_fl,
+       fn_data_json_fl,
+       fn_printf_va_fl,
+};
diff --git a/trace2/tr2_tls.c b/trace2/tr2_tls.c
new file mode 100644 (file)
index 0000000..8e65b03
--- /dev/null
@@ -0,0 +1,164 @@
+#include "cache.h"
+#include "thread-utils.h"
+#include "trace2/tr2_tls.h"
+
+/*
+ * Initialize size of the thread stack for nested regions.
+ * This is used to store nested region start times.  Note that
+ * this stack is per-thread and not per-trace-key.
+ */
+#define TR2_REGION_NESTING_INITIAL_SIZE (100)
+
+static struct tr2tls_thread_ctx *tr2tls_thread_main;
+static uint64_t tr2tls_us_start_main;
+
+static pthread_mutex_t tr2tls_mutex;
+static pthread_key_t tr2tls_key;
+
+static int tr2_next_thread_id; /* modify under lock */
+
+struct tr2tls_thread_ctx *tr2tls_create_self(const char *thread_name)
+{
+       uint64_t us_now = getnanotime() / 1000;
+       struct tr2tls_thread_ctx *ctx = xcalloc(1, sizeof(*ctx));
+
+       /*
+        * Implicitly "tr2tls_push_self()" to capture the thread's start
+        * time in array_us_start[0].  For the main thread this gives us the
+        * application run time.
+        */
+       ctx->alloc = TR2_REGION_NESTING_INITIAL_SIZE;
+       ctx->array_us_start = (uint64_t *)xcalloc(ctx->alloc, sizeof(uint64_t));
+       ctx->array_us_start[ctx->nr_open_regions++] = us_now;
+
+       ctx->thread_id = tr2tls_locked_increment(&tr2_next_thread_id);
+
+       strbuf_init(&ctx->thread_name, 0);
+       if (ctx->thread_id)
+               strbuf_addf(&ctx->thread_name, "th%02d:", ctx->thread_id);
+       strbuf_addstr(&ctx->thread_name, thread_name);
+       if (ctx->thread_name.len > TR2_MAX_THREAD_NAME)
+               strbuf_setlen(&ctx->thread_name, TR2_MAX_THREAD_NAME);
+
+       pthread_setspecific(tr2tls_key, ctx);
+
+       return ctx;
+}
+
+struct tr2tls_thread_ctx *tr2tls_get_self(void)
+{
+       struct tr2tls_thread_ctx *ctx = pthread_getspecific(tr2tls_key);
+
+       /*
+        * If the thread-proc did not call trace2_thread_start(), we won't
+        * have any TLS data associated with the current thread.  Fix it
+        * here and silently continue.
+        */
+       if (!ctx)
+               ctx = tr2tls_create_self("unknown");
+
+       return ctx;
+}
+
+int tr2tls_is_main_thread(void)
+{
+       struct tr2tls_thread_ctx *ctx = pthread_getspecific(tr2tls_key);
+
+       return ctx == tr2tls_thread_main;
+}
+
+void tr2tls_unset_self(void)
+{
+       struct tr2tls_thread_ctx *ctx;
+
+       ctx = tr2tls_get_self();
+
+       pthread_setspecific(tr2tls_key, NULL);
+
+       free(ctx->array_us_start);
+       free(ctx);
+}
+
+void tr2tls_push_self(uint64_t us_now)
+{
+       struct tr2tls_thread_ctx *ctx = tr2tls_get_self();
+
+       ALLOC_GROW(ctx->array_us_start, ctx->nr_open_regions + 1, ctx->alloc);
+       ctx->array_us_start[ctx->nr_open_regions++] = us_now;
+}
+
+void tr2tls_pop_self(void)
+{
+       struct tr2tls_thread_ctx *ctx = tr2tls_get_self();
+
+       if (!ctx->nr_open_regions)
+               BUG("no open regions in thread '%s'", ctx->thread_name.buf);
+
+       ctx->nr_open_regions--;
+}
+
+void tr2tls_pop_unwind_self(void)
+{
+       struct tr2tls_thread_ctx *ctx = tr2tls_get_self();
+
+       while (ctx->nr_open_regions > 1)
+               tr2tls_pop_self();
+}
+
+uint64_t tr2tls_region_elasped_self(uint64_t us)
+{
+       struct tr2tls_thread_ctx *ctx;
+       uint64_t us_start;
+
+       ctx = tr2tls_get_self();
+       if (!ctx->nr_open_regions)
+               return 0;
+
+       us_start = ctx->array_us_start[ctx->nr_open_regions - 1];
+
+       return us - us_start;
+}
+
+uint64_t tr2tls_absolute_elapsed(uint64_t us)
+{
+       if (!tr2tls_thread_main)
+               return 0;
+
+       return us - tr2tls_us_start_main;
+}
+
+void tr2tls_init(void)
+{
+       pthread_key_create(&tr2tls_key, NULL);
+       init_recursive_mutex(&tr2tls_mutex);
+
+       tr2tls_thread_main = tr2tls_create_self("main");
+       /*
+        * Keep a copy of the absolute start time of the main thread
+        * in a fixed variable since other threads need to access it.
+        * This also eliminates the need to lock accesses to the main
+        * thread's array (because of reallocs).
+        */
+       tr2tls_us_start_main = tr2tls_thread_main->array_us_start[0];
+}
+
+void tr2tls_release(void)
+{
+       tr2tls_unset_self();
+       tr2tls_thread_main = NULL;
+
+       pthread_mutex_destroy(&tr2tls_mutex);
+       pthread_key_delete(tr2tls_key);
+}
+
+int tr2tls_locked_increment(int *p)
+{
+       int current_value;
+
+       pthread_mutex_lock(&tr2tls_mutex);
+       current_value = *p;
+       *p = current_value + 1;
+       pthread_mutex_unlock(&tr2tls_mutex);
+
+       return current_value;
+}
diff --git a/trace2/tr2_tls.h b/trace2/tr2_tls.h
new file mode 100644 (file)
index 0000000..bb80e3f
--- /dev/null
@@ -0,0 +1,97 @@
+#ifndef TR2_TLS_H
+#define TR2_TLS_H
+
+#include "strbuf.h"
+
+/*
+ * Arbitry limit for thread names for column alignment.
+ */
+#define TR2_MAX_THREAD_NAME (24)
+
+struct tr2tls_thread_ctx {
+       struct strbuf thread_name;
+       uint64_t *array_us_start;
+       int alloc;
+       int nr_open_regions; /* plays role of "nr" in ALLOC_GROW */
+       int thread_id;
+};
+
+/*
+ * Create TLS data for the current thread.  This gives us a place to
+ * put per-thread data, such as thread start time, function nesting
+ * and a per-thread label for our messages.
+ *
+ * We assume the first thread is "main".  Other threads are given
+ * non-zero thread-ids to help distinguish messages from concurrent
+ * threads.
+ *
+ * Truncate the thread name if necessary to help with column alignment
+ * in printf-style messages.
+ *
+ * In this and all following functions the term "self" refers to the
+ * current thread.
+ */
+struct tr2tls_thread_ctx *tr2tls_create_self(const char *thread_name);
+
+/*
+ * Get our TLS data.
+ */
+struct tr2tls_thread_ctx *tr2tls_get_self(void);
+
+/*
+ * return true if the current thread is the main thread.
+ */
+int tr2tls_is_main_thread(void);
+
+/*
+ * Free our TLS data.
+ */
+void tr2tls_unset_self(void);
+
+/*
+ * Begin a new nested region and remember the start time.
+ */
+void tr2tls_push_self(uint64_t us_now);
+
+/*
+ * End the innermost nested region.
+ */
+void tr2tls_pop_self(void);
+
+/*
+ * Pop any extra (above the first) open regions on the current
+ * thread and discard.  During a thread-exit, we should only
+ * have region[0] that was pushed in trace2_thread_start() if
+ * the thread exits normally.
+ */
+void tr2tls_pop_unwind_self(void);
+
+/*
+ * Compute the elapsed time since the innermost region in the
+ * current thread started and the given time (usually now).
+ */
+uint64_t tr2tls_region_elasped_self(uint64_t us);
+
+/*
+ * Compute the elapsed time since the main thread started
+ * and the given time (usually now).  This is assumed to
+ * be the absolute run time of the process.
+ */
+uint64_t tr2tls_absolute_elapsed(uint64_t us);
+
+/*
+ * Initialize the tr2 TLS system.
+ */
+void tr2tls_init(void);
+
+/*
+ * Free all tr2 TLS resources.
+ */
+void tr2tls_release(void);
+
+/*
+ * Protected increment of an integer.
+ */
+int tr2tls_locked_increment(int *p);
+
+#endif /* TR2_TLS_H */
index 1f52c95fd87b1a02968727bde71dcc1eddc50410..cec83bd663d0f27589bd09176e38b084270f56c4 100644 (file)
@@ -127,6 +127,8 @@ static struct child_process *get_helper(struct transport *transport)
                argv_array_pushf(&helper->env_array, "%s=%s",
                                 GIT_DIR_ENVIRONMENT, get_git_dir());
 
+       helper->trace2_child_class = helper->args.argv[0]; /* "remote-<name>" */
+
        code = start_command(helper);
        if (code < 0 && errno == ENOENT)
                die(_("unable to find remote helper for '%s'"), data->name);
index e078812897eddefcd5a55a7d474dd4a7a89434fc..d0608df5c90cab4d2e2a2071a7416aeac75004e1 100644 (file)
@@ -1062,6 +1062,7 @@ static int run_pre_push_hook(struct transport *transport,
 
        proc.argv = argv;
        proc.in = -1;
+       proc.trace2_hook_name = "pre-push";
 
        if (start_command(&proc)) {
                finish_command(&proc);
diff --git a/usage.c b/usage.c
index cc803336bd5e6761b7fd50c33dba5aa9f734c4ba..2fdb20086bd695eaad57ef7574ce4e02655e96c1 100644 (file)
--- a/usage.c
+++ b/usage.c
@@ -22,17 +22,48 @@ void vreportf(const char *prefix, const char *err, va_list params)
 static NORETURN void usage_builtin(const char *err, va_list params)
 {
        vreportf("usage: ", err, params);
+
+       /*
+        * When we detect a usage error *before* the command dispatch in
+        * cmd_main(), we don't know what verb to report.  Force it to this
+        * to facilitate post-processing.
+        */
+       trace2_cmd_name("_usage_");
+
+       /*
+        * Currently, the (err, params) are usually just the static usage
+        * string which isn't very useful here.  Usually, the call site
+        * manually calls fprintf(stderr,...) with the actual detailed
+        * syntax error before calling usage().
+        *
+        * TODO It would be nice to update the call sites to pass both
+        * the static usage string and the detailed error message.
+        */
+
        exit(129);
 }
 
 static NORETURN void die_builtin(const char *err, va_list params)
 {
+       /*
+        * We call this trace2 function first and expect it to va_copy 'params'
+        * before using it (because an 'ap' can only be walked once).
+        */
+       trace2_cmd_error_va(err, params);
+
        vreportf("fatal: ", err, params);
+
        exit(128);
 }
 
 static void error_builtin(const char *err, va_list params)
 {
+       /*
+        * We call this trace2 function first and expect it to va_copy 'params'
+        * before using it (because an 'ap' can only be walked once).
+        */
+       trace2_cmd_error_va(err, params);
+
        vreportf("error: ", err, params);
 }
 
index 1f564b12d259956fa71fb0dce78c6e4c3c006897..445a36204a69cf69f2d3e87ea6d308a6b5a9ab29 100644 (file)
@@ -748,12 +748,23 @@ static int has_unmerged(struct wt_status *s)
 
 void wt_status_collect(struct wt_status *s)
 {
+       trace2_region_enter("status", "worktrees", s->repo);
        wt_status_collect_changes_worktree(s);
-       if (s->is_initial)
+       trace2_region_leave("status", "worktrees", s->repo);
+
+       if (s->is_initial) {
+               trace2_region_enter("status", "initial", s->repo);
                wt_status_collect_changes_initial(s);
-       else
+               trace2_region_leave("status", "initial", s->repo);
+       } else {
+               trace2_region_enter("status", "index", s->repo);
                wt_status_collect_changes_index(s);
+               trace2_region_leave("status", "index", s->repo);
+       }
+
+       trace2_region_enter("status", "untracked", s->repo);
        wt_status_collect_untracked(s);
+       trace2_region_leave("status", "untracked", s->repo);
 
        wt_status_get_state(s->repo, &s->state, s->branch && !strcmp(s->branch, "HEAD"));
        if (s->state.merge_in_progress && !has_unmerged(s))
@@ -2291,6 +2302,13 @@ static void wt_porcelain_v2_print(struct wt_status *s)
 
 void wt_status_print(struct wt_status *s)
 {
+       trace2_data_intmax("status", s->repo, "count/changed", s->change.nr);
+       trace2_data_intmax("status", s->repo, "count/untracked",
+                          s->untracked.nr);
+       trace2_data_intmax("status", s->repo, "count/ignored", s->ignored.nr);
+
+       trace2_region_enter("status", "print", s->repo);
+
        switch (s->status_format) {
        case STATUS_FORMAT_SHORT:
                wt_shortstatus_print(s);
@@ -2309,6 +2327,8 @@ void wt_status_print(struct wt_status *s)
                wt_longstatus_print(s);
                break;
        }
+
+       trace2_region_leave("status", "print", s->repo);
 }
 
 /**