From d4ff92659244a4783e424fa41b6f83645d8920c1 Mon Sep 17 00:00:00 2001 From: John Garry Date: Wed, 30 Mar 2022 18:22:54 +0800 Subject: [PATCH] perf tools: Stop depending on .git files for building PERF-VERSION-FILE This essentially reverts commit c72e3f04b45fb2e5 ("tools/perf/build: Speed up git-version test on re-make") and commit 4e666cdb06eede20 ("perf tools: Fix dependency for version file creation") In commit c72e3f04b45fb2e5 ("tools/perf/build: Speed up git-version test on re-make"), a makefile dependency on .git/HEAD was added. The background is that running PERF-VERSION-FILE is relatively slow, and commands like "git describe" are particularly slow. In commit 4e666cdb06eede20 ("perf tools: Fix dependency for version file creation"), an additional dependency on .git/ORIG_HEAD was added, as .git/HEAD may not change for "git reset --hard HEAD^" command. However, depending on whether we're on a branch or not, a "git cherry-pick" may not lead to the version being updated. As discussed with the git community in [0], using git internal files for dependencies is not reliable. Commit 4e666cdb06ee also breaks some build scenarios [1]. As mentioned, c72e3f04b45fb2e5 ("tools/perf/build: Speed up git-version test on re-make") was added to speed up the build. However in commit 7572733b84997d23 ("perf tools: Fix version kernel tag") we removed the call to "git describe", so just revert Makefile.perf back to same as pre c72e3f04b45fb2e5 ("tools/perf/build: Speed up git-version test on re-make") and the build should not be so slow, as below: Pre 7572733b8499: $> time util/PERF-VERSION-GEN PERF_VERSION = 5.17.rc8.g4e666cdb06ee real 0m0.110s user 0m0.091s sys 0m0.019s Post 7572733b8499: $> time util/PERF-VERSION-GEN PERF_VERSION = 5.17.rc8.g7572733b8499 real 0m0.039s user 0m0.036s sys 0m0.007s [0] https://lore.kernel.org/git/87wngkpddp.fsf@igel.home/T/#m4a4dd6de52fdbe21179306cd57b3761eb07f45f8 [1] https://lore.kernel.org/linux-perf-users/20220329093120.4173283-1-matthieu.baerts@tessares.net/T/#u Committer testing: After a fresh rebuild using 'make -C tools/perf O=/tmp/build/perf install-bin': $ perf -v perf version 5.17.g162f9db407b6 $ git log --oneline -1 162f9db407b6a6e5 (HEAD -> perf/core) perf tools: Stop depending on .git files for building PERF-VERSION-FILE $ Now using a detached tarball, i.e. outside the kernel source tree: $ ls -la perf*tar ls: cannot access 'perf*tar': No such file or directory $ make perf-tar-src-pkg TAR PERF_VERSION = 5.17.g31d10b3ef133 $ ls -la perf*tar -rw-r--r--. 1 acme acme 22241280 Mar 30 13:26 perf-5.17.0.tar $ mv perf-5.17.0.tar /tmp $ cd /tmp $ tar xf perf-5.17.0.tar $ cd perf-5.17.0/ $ make -C tools/perf |& tail CC util/pmu.o CC util/pmu-flex.o CC util/expr-flex.o CC util/expr.o LD util/scripting-engines/perf-in.o LD util/intel-pt-decoder/perf-in.o LD util/perf-in.o LD perf-in.o LINK perf make: Leaving directory '/tmp/perf-5.17.0/tools/perf' $ tools/perf/perf -v perf version 5.17.g31d10b3ef133 $ pwd /tmp/perf-5.17.0 $ cat PERF-VERSION-FILE #define PERF_VERSION "5.17.g31d10b3ef133" $ Fixes: 4e666cdb06eede20 ("perf tools: Fix dependency for version file creation") Reported-by: Matthieu Baerts Signed-off-by: John Garry Tested-by: Arnaldo Carvalho de Melo Tested-by: Matthieu Baerts Cc: Alexander Shishkin Cc: Ian Rogers Cc: Ingo Molnar Cc: Jiri Olsa Cc: John Garry Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Link: https://lore.kernel.org/r/1648635774-14581-1-git-send-email-john.garry@huawei.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/Makefile.perf | 14 ++------------ 1 file changed, 2 insertions(+), 12 deletions(-) diff --git a/tools/perf/Makefile.perf b/tools/perf/Makefile.perf index 0520c8635d18..69473a836bae 100644 --- a/tools/perf/Makefile.perf +++ b/tools/perf/Makefile.perf @@ -691,9 +691,8 @@ $(OUTPUT)common-cmds.h: $(wildcard Documentation/perf-*.txt) $(SCRIPTS) : % : %.sh $(QUIET_GEN)$(INSTALL) '$@.sh' '$(OUTPUT)$@' -$(OUTPUT)PERF-VERSION-FILE: ../../.git/HEAD ../../.git/ORIG_HEAD +$(OUTPUT)PERF-VERSION-FILE: .FORCE-PERF-VERSION-FILE $(Q)$(SHELL_PATH) util/PERF-VERSION-GEN $(OUTPUT) - $(Q)touch $(OUTPUT)PERF-VERSION-FILE # These can record PERF_VERSION perf.spec $(SCRIPTS) \ @@ -1139,21 +1138,12 @@ else @echo "FEATURE-DUMP file available in $(OUTPUT)FEATURE-DUMP" endif -# -# Trick: if ../../.git does not exist - we are building out of tree for example, -# then force version regeneration: -# -ifeq ($(wildcard ../../.git/HEAD),) - GIT-HEAD-PHONY = ../../.git/HEAD ../../.git/ORIG_HEAD -else - GIT-HEAD-PHONY = -endif FORCE: .PHONY: all install clean config-clean strip install-gtk .PHONY: shell_compatibility_test please_set_SHELL_PATH_to_a_more_modern_shell -.PHONY: $(GIT-HEAD-PHONY) TAGS tags cscope FORCE prepare +.PHONY: .FORCE-PERF-VERSION-FILE TAGS tags cscope FORCE prepare .PHONY: libtraceevent_plugins archheaders endif # force_fixdep -- 2.34.1