Merge branch 'jk/cocci-batch' into jch

Optionally "make coccicheck" can feed multiple source files to
spatch, gaining performance while spending more memory.

* jk/cocci-batch:
  coccicheck: make batch size of 0 mean "unlimited"
  coccicheck: optionally batch spatch invocations

Author: gitster

Makefile

@@ -1173,8 +1173,11 @@ 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.
+# Setting it to 0 will feed all files in a single spatch invocation.
 SPATCH_FLAGS = --all-includes --patch .
+SPATCH_BATCH_SIZE = 1
 
 include config.mak.uname
 -include config.mak.autogen
@@ -2809,12 +2812,14 @@ 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 $$ret != 0; \
+	if test $(SPATCH_BATCH_SIZE) = 0; then \
+		limit=; \
+	else \
+		limit='-n $(SPATCH_BATCH_SIZE)'; \
+	fi; \
+	if ! echo $(COCCI_SOURCES) | xargs $$limit \
+		$(SPATCH) --sp-file $< $(SPATCH_FLAGS) \
+		>$@+ 2>$@.log; \
 	then \
 		cat $@.log; \
 		exit 1; \