[PATCH v5 12/13] cocci: run against a generated ALL.cocci
- From
Ævar Arnfjörð Bjarmason <avarab@gmail.com>
- Date
- Nov 1, 2022, 22:35 UTC
- Message-ID
- <patch-v5-12.13-55d2f638359-20221101T222616Z-avarab@gmail.com>
- In-Reply-To
- <cover-v5-00.13-00000000000-20221101T222616Z-avarab@gmail.com>
The preceding commits to make the "coccicheck" target incremental made it slower in some cases. As an optimization let's not have the many=many mapping of <*.cocci>=<*.[ch]>, but instead concat the <*.cocci> into an ALL.cocci, and then run one-to-many ALL.cocci=<*.[ch]>.
A "make coccicheck" is now around 2x as fast as it was on "master", and around 1.5x as fast as the preceding change to make the run incremental:
$ git hyperfine -L rev origin/master,HEAD~,HEAD -p 'make clean' 'make coccicheck SPATCH=spatch COCCI_SOURCES="$(echo $(ls o*.c builtin/h*.c))"' -r 3 Benchmark 1: make coccicheck SPATCH=spatch COCCI_SOURCES="$(echo $(ls o*.c builtin/h*.c))"' in 'origin/master Time (mean ± σ): 4.258 s ± 0.015 s [User: 27.432 s, System: 1.532 s] Range (min … max): 4.241 s … 4.268 s 3 runs
Benchmark 2: make coccicheck SPATCH=spatch COCCI_SOURCES="$(echo $(ls o*.c builtin/h*.c))"' in 'HEAD~ Time (mean ± σ): 5.365 s ± 0.079 s [User: 36.899 s, System: 1.810 s] Range (min … max): 5.281 s … 5.436 s 3 runs
Benchmark 3: make coccicheck SPATCH=spatch COCCI_SOURCES="$(echo $(ls o*.c builtin/h*.c))"' in 'HEAD Time (mean ± σ): 2.725 s ± 0.063 s [User: 14.796 s, System: 0.233 s] Range (min … max): 2.667 s … 2.792 s 3 runs
Summary 'make coccicheck SPATCH=spatch COCCI_SOURCES="$(echo $(ls o*.c builtin/h*.c))"' in 'HEAD' ran 1.56 ± 0.04 times faster than 'make coccicheck SPATCH=spatch COCCI_SOURCES="$(echo $(ls o*.c builtin/h*.c))"' in 'origin/master' 1.97 ± 0.05 times faster than 'make coccicheck SPATCH=spatch COCCI_SOURCES="$(echo $(ls o*.c builtin/h*.c))"' in 'HEAD~'
This can be turned off with SPATCH_CONCAT_COCCI, but as the beneficiaries of "SPATCH_CONCAT_COCCI=" would mainly be those developing the *.cocci rules themselves, let's leave this optimization on by default.
For more information see my "Optimizing *.cocci rules by concat'ing them" (<220901.8635dbjfko.gmgdl@evledraar.gmail.com>) on the cocci@inria.fr mailing list.
This potentially changes the results of our *.cocci rules, but as noted in that discussion it should be safe for our use. We don't name rules, or if we do their names don't conflict across our *.cocci files.
To the extent that we'd have any inter-dependencies between rules this doesn't make that worse, as we'd have them now if we ran "make coccicheck", applied the results, and would then have (due to hypothetical interdependencies) suggested changes on the subsequent "make coccicheck".
Our "coccicheck-test" target makes use of the ALL.cocci when running tests, e.g. when testing unused.{c,out} we test it against ALL.cocci, not unused.cocci. We thus assert (to the extent that we have test coverage) that this concatenation doesn't change the expected results of running these rules.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> --- Makefile | 38 ++++++++++++++++++++++++++++++++++++++ contrib/coccinelle/README | 13 +++++++++++++ 2 files changed, 51 insertions(+)
diff --git a/Makefile b/Makefile index 44c906b65d5..36cefe3b1d6 100644 --- a/Makefile +++ b/Makefile @@ -1314,6 +1314,29 @@ SPATCH_TEST_FLAGS = # COMPUTE_HEADER_DEPENDENCIES=no this will be unset too. SPATCH_USE_O_DEPENDENCIES = YesPlease +# Set SPATCH_CONCAT_COCCI to concatenate the contrib/cocci/*.cocci +# files into a single contrib/cocci/ALL.cocci before running +# "coccicheck". +# +# Pros: +# +# - Speeds up a one-shot run of "make coccicheck", as we won't have to +# parse *.[ch] files N times for the N *.cocci rules +# +# Cons: +# +# - Will make incremental development of *.cocci slower, as +# e.g. changing strbuf.cocci will re-run all *.cocci. +# +# - Makes error and performance analysis harder, as rules will be +# applied from a monolithic ALL.cocci, rather than +# e.g. strbuf.cocci. To work around this either undefine this, or +# generate a specific patch, e.g. this will always use strbuf.cocci, +# not ALL.cocci: +# +# make contrib/coccinelle/strbuf.cocci.patch +SPATCH_CONCAT_COCCI = YesPlease + # Rebuild 'coccicheck' if $(SPATCH), its flags etc. change TRACK_SPATCH_DEFINES = TRACK_SPATCH_DEFINES += $(SPATCH) @@ -3163,9 +3186,12 @@ check: $(GENERATED_H) exit 1; \ fi +COCCI_GEN_ALL = .build/contrib/coccinelle/ALL.cocci COCCI_GLOB = $(wildcard contrib/coccinelle/*.cocci) COCCI_RULES_TRACKED = $(COCCI_GLOB:%=.build/%) +COCCI_RULES_TRACKED_NO_PENDING = $(filter-out %.pending.cocci,$(COCCI_RULES_TRACKED)) COCCI_RULES = +COCCI_RULES += $(COCCI_GEN_ALL) COCCI_RULES += $(COCCI_RULES_TRACKED) COCCI_NAMES = COCCI_NAMES += $(COCCI_RULES:.build/contrib/coccinelle/%.cocci=%) @@ -3200,6 +3226,10 @@ $(COCCI_RULES_TRACKED): .build/% : % $(call mkdir_p_parent_template) $(QUIET_GEN) >$@ +$(COCCI_GEN_ALL): $(COCCI_RULES_TRACKED_NO_PENDING) + $(call mkdir_p_parent_template) + $(QUIET_SPATCH_CAT)cat $^ >$@ + ifeq ($(COMPUTE_HEADER_DEPENDENCIES),no) SPATCH_USE_O_DEPENDENCIES = endif @@ -3256,7 +3286,11 @@ COCCI_TEST_RES_GEN = $(addprefix .build/,$(COCCI_TEST_RES)) $(COCCI_TEST_RES_GEN): GIT-SPATCH-DEFINES $(COCCI_TEST_RES_GEN): .build/%.res : %.c $(COCCI_TEST_RES_GEN): .build/%.res : %.res +ifdef SPATCH_CONCAT_COCCI +$(COCCI_TEST_RES_GEN): .build/contrib/coccinelle/tests/%.res : $(COCCI_GEN_ALL) +else $(COCCI_TEST_RES_GEN): .build/contrib/coccinelle/tests/%.res : contrib/coccinelle/%.cocci +endif $(call mkdir_p_parent_template) $(QUIET_SPATCH_TEST)$(SPATCH) $(SPATCH_TEST_FLAGS) \ --very-quiet --no-show-diff \ @@ -3269,7 +3303,11 @@ $(COCCI_TEST_RES_GEN): .build/contrib/coccinelle/tests/%.res : contrib/coccinell coccicheck-test: $(COCCI_TEST_RES_GEN) coccicheck: coccicheck-test +ifdef SPATCH_CONCAT_COCCI +coccicheck: contrib/coccinelle/ALL.cocci.patch +else coccicheck: $(COCCICHECK_PATCHES_INTREE) +endif # See contrib/coccinelle/README coccicheck-pending: coccicheck-test diff --git a/contrib/coccinelle/README b/contrib/coccinelle/README index 09ea8298e19..09b72bfd4e7 100644 --- a/contrib/coccinelle/README +++ b/contrib/coccinelle/README @@ -57,3 +57,16 @@ Git-specific tips & things to know about how we run "spatch": To disable this behavior use the "SPATCH_USE_O_DEPENDENCIES=NoThanks" flag. + + * To speed up our rules the "make coccicheck" target will by default + concatenate all of the *.cocci files here into an "ALL.cocci", and + apply it to each source file. + + This makes the run faster, as we don't need to run each rule + against each source file. See the Makefile for further discussion, + this behavior can be disabled with "SPATCH_CONCAT_COCCI=". + + But since they're concatenated any <id> in the <rulname> (e.g. "@ + my_name", v.s. anonymous "@@") needs to be unique across all our + *.cocci files. You should only need to name rules if other rules + depend on them (currently only one rule is named).
-- 2.38.0.1280.g8136eb6fab2