coccicheck: optionally batch spatch invocations

diff --git a/Makefile b/Makefile
index 9f1b6e8926682c82530baa597794544b89d88c3a..daba958b8f4514af18ecd1c6b116b9fe38a40afc 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -1174,8 +1174,10 @@ PTHREAD_CFLAGS =
 SPARSE_FLAGS ?=
 SP_EXTRA_FLAGS =
 
-# For the 'coccicheck' target
+# For the 'coccicheck' target; setting SPATCH_BATCH_SIZE higher will
+# usually result in less CPU usage at the cost of higher peak memory.
 SPATCH_FLAGS = --all-includes --patch .
+SPATCH_BATCH_SIZE = 1
 
 include config.mak.uname
 -include config.mak.autogen
@@ -2790,12 +2792,9 @@ endif
 
 %.cocci.patch: %.cocci $(COCCI_SOURCES)
        @echo '    ' SPATCH $<; \
-       ret=0; \
-       for f in $(COCCI_SOURCES); do \
-               $(SPATCH) --sp-file $< $$f $(SPATCH_FLAGS) || \
-                       { ret=$$?; break; }; \
-       done >$@+ 2>$@.log; \
-       if test $$ret != 0; \
+       if ! echo $(COCCI_SOURCES) | xargs -n $(SPATCH_BATCH_SIZE) \
+               $(SPATCH) --sp-file $< $(SPATCH_FLAGS) \
+               >$@+ 2>$@.log; \
        then \
                cat $@.log; \
                exit 1; \