Merge branch 'ds/commit-graph-lockfile-fix'
authorJunio C Hamano <gitster@pobox.com>
Tue, 4 Sep 2018 21:31:39 +0000 (14:31 -0700)
committerJunio C Hamano <gitster@pobox.com>
Tue, 4 Sep 2018 21:31:39 +0000 (14:31 -0700)
"git merge-base" in 2.19-rc1 has performance regression when the
(experimental) commit-graph feature is in use, which has been
mitigated.

* ds/commit-graph-lockfile-fix:
commit: don't use generation numbers if not needed

1  2 
commit.c
diff --combined commit.c
index 1a6e632185346f518ed389f2d479c807a5f49927,23db654d64b8d3c10c21988f12b449d1d5bcbec5..449c1f4920cff631f5cf2479772c350c9b8b7325
+++ b/commit.c
@@@ -2,21 -2,17 +2,21 @@@
  #include "tag.h"
  #include "commit.h"
  #include "commit-graph.h"
 +#include "repository.h"
 +#include "object-store.h"
  #include "pkt-line.h"
  #include "utf8.h"
  #include "diff.h"
  #include "revision.h"
  #include "notes.h"
 +#include "alloc.h"
  #include "gpg-interface.h"
  #include "mergesort.h"
  #include "commit-slab.h"
  #include "prio-queue.h"
  #include "sha1-lookup.h"
  #include "wt-status.h"
 +#include "advice.h"
  
  static struct commit_extra_header *read_commit_extra_header_lines(const char *buf, size_t len, const char **);
  
@@@ -24,26 -20,24 +24,26 @@@ int save_commit_buffer = 1
  
  const char *commit_type = "commit";
  
 -struct commit *lookup_commit_reference_gently(const struct object_id *oid,
 -                                            int quiet)
 +struct commit *lookup_commit_reference_gently(struct repository *r,
 +              const struct object_id *oid, int quiet)
  {
 -      struct object *obj = deref_tag(parse_object(oid), NULL, 0);
 +      struct object *obj = deref_tag(r,
 +                                     parse_object(r, oid),
 +                                     NULL, 0);
  
        if (!obj)
                return NULL;
 -      return object_as_type(obj, OBJ_COMMIT, quiet);
 +      return object_as_type(r, obj, OBJ_COMMIT, quiet);
  }
  
 -struct commit *lookup_commit_reference(const struct object_id *oid)
 +struct commit *lookup_commit_reference(struct repository *r, const struct object_id *oid)
  {
 -      return lookup_commit_reference_gently(oid, 0);
 +      return lookup_commit_reference_gently(r, oid, 0);
  }
  
  struct commit *lookup_commit_or_die(const struct object_id *oid, const char *ref_name)
  {
 -      struct commit *c = lookup_commit_reference(oid);
 +      struct commit *c = lookup_commit_reference(the_repository, oid);
        if (!c)
                die(_("could not parse %s"), ref_name);
        if (oidcmp(oid, &c->object.oid)) {
        return c;
  }
  
 -struct commit *lookup_commit(const struct object_id *oid)
 +struct commit *lookup_commit(struct repository *r, const struct object_id *oid)
  {
 -      struct object *obj = lookup_object(oid->hash);
 +      struct object *obj = lookup_object(r, oid->hash);
        if (!obj)
 -              return create_object(oid->hash, alloc_commit_node());
 -      return object_as_type(obj, OBJ_COMMIT, 0);
 +              return create_object(r, oid->hash,
 +                                   alloc_commit_node(r));
 +      return object_as_type(r, obj, OBJ_COMMIT, 0);
  }
  
  struct commit *lookup_commit_reference_by_name(const char *name)
@@@ -69,7 -62,7 +69,7 @@@
  
        if (get_oid_committish(name, &oid))
                return NULL;
 -      commit = lookup_commit_reference(&oid);
 +      commit = lookup_commit_reference(the_repository, &oid);
        if (parse_commit(commit))
                return NULL;
        return commit;
@@@ -102,44 -95,41 +102,44 @@@ static timestamp_t parse_commit_date(co
        return parse_timestamp(dateptr, NULL, 10);
  }
  
 -static struct commit_graft **commit_graft;
 -static int commit_graft_alloc, commit_graft_nr;
 -
  static const unsigned char *commit_graft_sha1_access(size_t index, void *table)
  {
        struct commit_graft **commit_graft_table = table;
        return commit_graft_table[index]->oid.hash;
  }
  
 -static int commit_graft_pos(const unsigned char *sha1)
 +static int commit_graft_pos(struct repository *r, const unsigned char *sha1)
  {
 -      return sha1_pos(sha1, commit_graft, commit_graft_nr,
 +      return sha1_pos(sha1, r->parsed_objects->grafts,
 +                      r->parsed_objects->grafts_nr,
                        commit_graft_sha1_access);
  }
  
 -int register_commit_graft(struct commit_graft *graft, int ignore_dups)
 +int register_commit_graft(struct repository *r, struct commit_graft *graft,
 +                        int ignore_dups)
  {
 -      int pos = commit_graft_pos(graft->oid.hash);
 +      int pos = commit_graft_pos(r, graft->oid.hash);
  
        if (0 <= pos) {
                if (ignore_dups)
                        free(graft);
                else {
 -                      free(commit_graft[pos]);
 -                      commit_graft[pos] = graft;
 +                      free(r->parsed_objects->grafts[pos]);
 +                      r->parsed_objects->grafts[pos] = graft;
                }
                return 1;
        }
        pos = -pos - 1;
 -      ALLOC_GROW(commit_graft, commit_graft_nr + 1, commit_graft_alloc);
 -      commit_graft_nr++;
 -      if (pos < commit_graft_nr)
 -              MOVE_ARRAY(commit_graft + pos + 1, commit_graft + pos,
 -                         commit_graft_nr - pos - 1);
 -      commit_graft[pos] = graft;
 +      ALLOC_GROW(r->parsed_objects->grafts,
 +                 r->parsed_objects->grafts_nr + 1,
 +                 r->parsed_objects->grafts_alloc);
 +      r->parsed_objects->grafts_nr++;
 +      if (pos < r->parsed_objects->grafts_nr)
 +              memmove(r->parsed_objects->grafts + pos + 1,
 +                      r->parsed_objects->grafts + pos,
 +                      (r->parsed_objects->grafts_nr - pos - 1) *
 +                      sizeof(*r->parsed_objects->grafts));
 +      r->parsed_objects->grafts[pos] = graft;
        return 0;
  }
  
@@@ -181,27 -171,18 +181,27 @@@ bad_graft_data
        return NULL;
  }
  
 -static int read_graft_file(const char *graft_file)
 +static int read_graft_file(struct repository *r, const char *graft_file)
  {
        FILE *fp = fopen_or_warn(graft_file, "r");
        struct strbuf buf = STRBUF_INIT;
        if (!fp)
                return -1;
 +      if (advice_graft_file_deprecated)
 +              advise(_("Support for <GIT_DIR>/info/grafts is deprecated\n"
 +                       "and will be removed in a future Git version.\n"
 +                       "\n"
 +                       "Please use \"git replace --convert-graft-file\"\n"
 +                       "to convert the grafts into replace refs.\n"
 +                       "\n"
 +                       "Turn this message off by running\n"
 +                       "\"git config advice.graftFileDeprecated false\""));
        while (!strbuf_getwholeline(&buf, fp, '\n')) {
                /* The format is just "Commit Parent1 Parent2 ...\n" */
                struct commit_graft *graft = read_graft_line(&buf);
                if (!graft)
                        continue;
 -              if (register_commit_graft(graft, 1))
 +              if (register_commit_graft(r, graft, 1))
                        error("duplicate graft data: %s", buf.buf);
        }
        fclose(fp);
        return 0;
  }
  
 -static void prepare_commit_graft(void)
 +static void prepare_commit_graft(struct repository *r)
  {
 -      static int commit_graft_prepared;
        char *graft_file;
  
 -      if (commit_graft_prepared)
 +      if (r->parsed_objects->commit_graft_prepared)
 +              return;
 +      if (!startup_info->have_repository)
                return;
 -      graft_file = get_graft_file();
 -      read_graft_file(graft_file);
 +
 +      graft_file = get_graft_file(r);
 +      read_graft_file(r, graft_file);
        /* make sure shallows are read */
 -      is_repository_shallow();
 -      commit_graft_prepared = 1;
 +      is_repository_shallow(r);
 +      r->parsed_objects->commit_graft_prepared = 1;
  }
  
 -struct commit_graft *lookup_commit_graft(const struct object_id *oid)
 +struct commit_graft *lookup_commit_graft(struct repository *r, const struct object_id *oid)
  {
        int pos;
 -      prepare_commit_graft();
 -      pos = commit_graft_pos(oid->hash);
 +      prepare_commit_graft(r);
 +      pos = commit_graft_pos(r, oid->hash);
        if (pos < 0)
                return NULL;
 -      return commit_graft[pos];
 +      return r->parsed_objects->grafts[pos];
  }
  
  int for_each_commit_graft(each_commit_graft_fn fn, void *cb_data)
  {
        int i, ret;
 -      for (i = ret = 0; i < commit_graft_nr && !ret; i++)
 -              ret = fn(commit_graft[i], cb_data);
 +      for (i = ret = 0; i < the_repository->parsed_objects->grafts_nr && !ret; i++)
 +              ret = fn(the_repository->parsed_objects->grafts[i], cb_data);
        return ret;
  }
  
  int unregister_shallow(const struct object_id *oid)
  {
 -      int pos = commit_graft_pos(oid->hash);
 +      int pos = commit_graft_pos(the_repository, oid->hash);
        if (pos < 0)
                return -1;
 -      if (pos + 1 < commit_graft_nr)
 -              MOVE_ARRAY(commit_graft + pos, commit_graft + pos + 1,
 -                         commit_graft_nr - pos - 1);
 -      commit_graft_nr--;
 +      if (pos + 1 < the_repository->parsed_objects->grafts_nr)
 +              MOVE_ARRAY(the_repository->parsed_objects->grafts + pos,
 +                         the_repository->parsed_objects->grafts + pos + 1,
 +                         the_repository->parsed_objects->grafts_nr - pos - 1);
 +      the_repository->parsed_objects->grafts_nr--;
        return 0;
  }
  
@@@ -261,32 -239,18 +261,32 @@@ struct commit_buffer 
        unsigned long size;
  };
  define_commit_slab(buffer_slab, struct commit_buffer);
 -static struct buffer_slab buffer_slab = COMMIT_SLAB_INIT(1, buffer_slab);
  
 -void set_commit_buffer(struct commit *commit, void *buffer, unsigned long size)
 +struct buffer_slab *allocate_commit_buffer_slab(void)
 +{
 +      struct buffer_slab *bs = xmalloc(sizeof(*bs));
 +      init_buffer_slab(bs);
 +      return bs;
 +}
 +
 +void free_commit_buffer_slab(struct buffer_slab *bs)
  {
 -      struct commit_buffer *v = buffer_slab_at(&buffer_slab, commit);
 +      clear_buffer_slab(bs);
 +      free(bs);
 +}
 +
 +void set_commit_buffer(struct repository *r, struct commit *commit, void *buffer, unsigned long size)
 +{
 +      struct commit_buffer *v = buffer_slab_at(
 +              r->parsed_objects->buffer_slab, commit);
        v->buffer = buffer;
        v->size = size;
  }
  
 -const void *get_cached_commit_buffer(const struct commit *commit, unsigned long *sizep)
 +const void *get_cached_commit_buffer(struct repository *r, const struct commit *commit, unsigned long *sizep)
  {
 -      struct commit_buffer *v = buffer_slab_peek(&buffer_slab, commit);
 +      struct commit_buffer *v = buffer_slab_peek(
 +              r->parsed_objects->buffer_slab, commit);
        if (!v) {
                if (sizep)
                        *sizep = 0;
  
  const void *get_commit_buffer(const struct commit *commit, unsigned long *sizep)
  {
 -      const void *ret = get_cached_commit_buffer(commit, sizep);
 +      const void *ret = get_cached_commit_buffer(the_repository, commit, sizep);
        if (!ret) {
                enum object_type type;
                unsigned long size;
 -              ret = read_sha1_file(commit->object.oid.hash, &type, &size);
 +              ret = read_object_file(&commit->object.oid, &type, &size);
                if (!ret)
                        die("cannot read commit object %s",
                            oid_to_hex(&commit->object.oid));
  
  void unuse_commit_buffer(const struct commit *commit, const void *buffer)
  {
 -      struct commit_buffer *v = buffer_slab_peek(&buffer_slab, commit);
 +      struct commit_buffer *v = buffer_slab_peek(
 +              the_repository->parsed_objects->buffer_slab, commit);
        if (!(v && v->buffer == buffer))
                free((void *)buffer);
  }
  
  void free_commit_buffer(struct commit *commit)
  {
 -      struct commit_buffer *v = buffer_slab_peek(&buffer_slab, commit);
 +      struct commit_buffer *v = buffer_slab_peek(
 +              the_repository->parsed_objects->buffer_slab, commit);
        if (v) {
                FREE_AND_NULL(v->buffer);
                v->size = 0;
@@@ -342,7 -304,7 +342,7 @@@ struct tree *get_commit_tree(const stru
        if (commit->graph_pos == COMMIT_NOT_FROM_GRAPH)
                BUG("commit has NULL tree, but was not loaded from commit-graph");
  
 -      return get_commit_tree_in_graph(commit);
 +      return get_commit_tree_in_graph(the_repository, commit);
  }
  
  struct object_id *get_commit_tree_oid(const struct commit *commit)
        return &get_commit_tree(commit)->object.oid;
  }
  
 +void release_commit_memory(struct commit *c)
 +{
 +      c->maybe_tree = NULL;
 +      c->index = 0;
 +      free_commit_buffer(c);
 +      free_commit_list(c->parents);
 +      /* TODO: what about commit->util? */
 +
 +      c->object.parsed = 0;
 +}
 +
  const void *detach_commit_buffer(struct commit *commit, unsigned long *sizep)
  {
 -      struct commit_buffer *v = buffer_slab_peek(&buffer_slab, commit);
 +      struct commit_buffer *v = buffer_slab_peek(
 +              the_repository->parsed_objects->buffer_slab, commit);
        void *ret;
  
        if (!v) {
        return ret;
  }
  
 -int parse_commit_buffer(struct commit *item, const void *buffer, unsigned long size, int check_graph)
 +int parse_commit_buffer(struct repository *r, struct commit *item, const void *buffer, unsigned long size, int check_graph)
  {
        const char *tail = buffer;
        const char *bufptr = buffer;
        struct object_id parent;
        struct commit_list **pptr;
        struct commit_graft *graft;
 -      const int tree_entry_len = GIT_SHA1_HEXSZ + 5;
 -      const int parent_entry_len = GIT_SHA1_HEXSZ + 7;
 +      const int tree_entry_len = the_hash_algo->hexsz + 5;
 +      const int parent_entry_len = the_hash_algo->hexsz + 7;
  
        if (item->object.parsed)
                return 0;
        if (tail <= bufptr + tree_entry_len + 1 || memcmp(bufptr, "tree ", 5) ||
                        bufptr[tree_entry_len] != '\n')
                return error("bogus commit object %s", oid_to_hex(&item->object.oid));
 -      if (get_sha1_hex(bufptr + 5, parent.hash) < 0)
 +      if (get_oid_hex(bufptr + 5, &parent) < 0)
                return error("bad tree pointer in commit %s",
                             oid_to_hex(&item->object.oid));
 -      item->maybe_tree = lookup_tree(&parent);
 +      item->maybe_tree = lookup_tree(r, &parent);
        bufptr += tree_entry_len + 1; /* "tree " + "hex sha1" + "\n" */
        pptr = &item->parents;
  
 -      graft = lookup_commit_graft(&item->object.oid);
 +      graft = lookup_commit_graft(r, &item->object.oid);
        while (bufptr + parent_entry_len < tail && !memcmp(bufptr, "parent ", 7)) {
                struct commit *new_parent;
  
                if (tail <= bufptr + parent_entry_len + 1 ||
 -                  get_sha1_hex(bufptr + 7, parent.hash) ||
 +                  get_oid_hex(bufptr + 7, &parent) ||
                    bufptr[parent_entry_len] != '\n')
                        return error("bad parents in commit %s", oid_to_hex(&item->object.oid));
                bufptr += parent_entry_len + 1;
                 */
                if (graft && (graft->nr_parent < 0 || grafts_replace_parents))
                        continue;
 -              new_parent = lookup_commit(&parent);
 +              new_parent = lookup_commit(r, &parent);
                if (new_parent)
                        pptr = &commit_list_insert(new_parent, pptr)->next;
        }
                int i;
                struct commit *new_parent;
                for (i = 0; i < graft->nr_parent; i++) {
 -                      new_parent = lookup_commit(&graft->parent[i]);
 +                      new_parent = lookup_commit(r,
 +                                                 &graft->parent[i]);
                        if (!new_parent)
                                continue;
                        pptr = &commit_list_insert(new_parent, pptr)->next;
        item->date = parse_commit_date(bufptr, tail);
  
        if (check_graph)
 -              load_commit_graph_info(item);
 +              load_commit_graph_info(the_repository, item);
  
        return 0;
  }
  
 -int parse_commit_gently(struct commit *item, int quiet_on_missing)
 +int parse_commit_internal(struct commit *item, int quiet_on_missing, int use_commit_graph)
  {
        enum object_type type;
        void *buffer;
                return -1;
        if (item->object.parsed)
                return 0;
 -      if (parse_commit_in_graph(item))
 +      if (use_commit_graph && parse_commit_in_graph(the_repository, item))
                return 0;
 -      buffer = read_sha1_file(item->object.oid.hash, &type, &size);
 +      buffer = read_object_file(&item->object.oid, &type, &size);
        if (!buffer)
                return quiet_on_missing ? -1 :
                        error("Could not read %s",
                return error("Object %s not a commit",
                             oid_to_hex(&item->object.oid));
        }
 -      ret = parse_commit_buffer(item, buffer, size, 0);
 +
 +      ret = parse_commit_buffer(the_repository, item, buffer, size, 0);
        if (save_commit_buffer && !ret) {
 -              set_commit_buffer(item, buffer, size);
 +              set_commit_buffer(the_repository, item, buffer, size);
                return 0;
        }
        free(buffer);
        return ret;
  }
  
 +int parse_commit_gently(struct commit *item, int quiet_on_missing)
 +{
 +      return parse_commit_internal(item, quiet_on_missing, 1);
 +}
 +
  void parse_commit_or_die(struct commit *item)
  {
        if (parse_commit(item))
@@@ -656,7 -599,7 +656,7 @@@ struct commit *pop_commit(struct commit
  define_commit_slab(indegree_slab, int);
  
  /* record author-date for each commit object */
 -define_commit_slab(author_date_slab, unsigned long);
 +define_commit_slab(author_date_slab, timestamp_t);
  
  static void record_author_date(struct author_date_slab *author_date,
                               struct commit *commit)
@@@ -874,6 -817,9 +874,9 @@@ static struct commit_list *paint_down_t
        int i;
        uint32_t last_gen = GENERATION_NUMBER_INFINITY;
  
+       if (!min_generation)
+               queue.compare = compare_commits_by_commit_date;
        one->object.flags |= PARENT1;
        if (!n) {
                commit_list_append(one, &result);
                struct commit_list *parents;
                int flags;
  
-               if (commit->generation > last_gen)
+               if (min_generation && commit->generation > last_gen)
                        BUG("bad generation skip %8x > %8x at %s",
                            commit->generation, last_gen,
                            oid_to_hex(&commit->object.oid));
@@@ -1327,7 -1273,7 +1330,7 @@@ static void handle_signed_tag(struct co
        desc = merge_remote_util(parent);
        if (!desc || !desc->obj)
                return;
 -      buf = read_sha1_file(desc->obj->oid.hash, &type, &size);
 +      buf = read_object_file(&desc->obj->oid, &type, &size);
        if (!buf || type != OBJ_TAG)
                goto free_return;
        len = parse_signature(buf, size);
@@@ -1409,19 -1355,17 +1412,19 @@@ struct commit_extra_header *read_commit
        return extra;
  }
  
 -void for_each_mergetag(each_mergetag_fn fn, struct commit *commit, void *data)
 +int for_each_mergetag(each_mergetag_fn fn, struct commit *commit, void *data)
  {
        struct commit_extra_header *extra, *to_free;
 +      int res = 0;
  
        to_free = read_commit_extra_headers(commit, NULL);
 -      for (extra = to_free; extra; extra = extra->next) {
 +      for (extra = to_free; !res && extra; extra = extra->next) {
                if (strcmp(extra->key, "mergetag"))
                        continue; /* not a merge tag */
 -              fn(commit, extra, data);
 +              res = fn(commit, extra, data);
        }
        free_commit_extra_headers(to_free);
 +      return res;
  }
  
  static inline int standard_header_field(const char *field, size_t len)
@@@ -1640,7 -1584,7 +1643,7 @@@ int commit_tree_extended(const char *ms
        int encoding_is_utf8;
        struct strbuf buffer;
  
 -      assert_sha1_type(tree->hash, OBJ_TREE);
 +      assert_oid_type(tree, OBJ_TREE);
  
        if (memchr(msg, '\0', msg_len))
                return error("a NUL byte in commit log message not allowed.");
        return result;
  }
  
 +define_commit_slab(merge_desc_slab, struct merge_remote_desc *);
 +static struct merge_desc_slab merge_desc_slab = COMMIT_SLAB_INIT(1, merge_desc_slab);
 +
 +struct merge_remote_desc *merge_remote_util(struct commit *commit)
 +{
 +      return *merge_desc_slab_at(&merge_desc_slab, commit);
 +}
 +
  void set_merge_remote_desc(struct commit *commit,
                           const char *name, struct object *obj)
  {
        struct merge_remote_desc *desc;
        FLEX_ALLOC_STR(desc, name, name);
        desc->obj = obj;
 -      commit->util = desc;
 +      *merge_desc_slab_at(&merge_desc_slab, commit) = desc;
  }
  
  struct commit *get_merge_parent(const char *name)
        struct object_id oid;
        if (get_oid(name, &oid))
                return NULL;
 -      obj = parse_object(&oid);
 +      obj = parse_object(the_repository, &oid);
        commit = (struct commit *)peel_to_type(name, 0, obj, OBJ_COMMIT);
 -      if (commit && !commit->util)
 +      if (commit && !merge_remote_util(commit))
                set_merge_remote_desc(commit, name, obj);
        return commit;
  }