From 0be314c20742cd62cd6e8fcfbcc4535fb2a99675 Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Fri, 4 Jul 2014 16:43:48 -0700 Subject: [PATCH 1/4] Use BASIC_FLAGS for profile feedback Use BASIC_CFLAGS instead of CFLAGS to set up the profile feedback option in the Makefile. This allows still overriding CFLAGS on the make command line without disabling profile feedback. Signed-off-by: Andi Kleen Signed-off-by: Junio C Hamano --- Makefile | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/Makefile b/Makefile index 07ea105837..a9770ac476 100644 --- a/Makefile +++ b/Makefile @@ -1552,13 +1552,13 @@ endif PROFILE_DIR := $(CURDIR) ifeq ("$(PROFILE)","GEN") - CFLAGS += -fprofile-generate=$(PROFILE_DIR) -DNO_NORETURN=1 + BASIC_CFLAGS += -fprofile-generate=$(PROFILE_DIR) -DNO_NORETURN=1 EXTLIBS += -lgcov export CCACHE_DISABLE = t V = 1 else ifneq ("$(PROFILE)","") - CFLAGS += -fprofile-use=$(PROFILE_DIR) -fprofile-correction -DNO_NORETURN=1 + BASIC_CFLAGS += -fprofile-use=$(PROFILE_DIR) -fprofile-correction -DNO_NORETURN=1 export CCACHE_DISABLE = t V = 1 endif From 8cd7ebc89e025f1d5bc4b247497e4cfd7fd8ec0f Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Fri, 4 Jul 2014 16:43:49 -0700 Subject: [PATCH 2/4] Don't define away __attribute__ on gcc Profile feedback sets -DNO_NORETURN, which causes the compat header file to go into a default #else block. That #else block defines away __attribute__(). Doing so causes all kinds of problems with the Linux and gcc system headers: in particular it makes the xmmintrin.h headers error out, breaking the build. Don't define away __attribute__ when __GNUC__ is set. Signed-off-by: Andi Kleen Signed-off-by: Junio C Hamano --- git-compat-util.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/git-compat-util.h b/git-compat-util.h index 96f55547a3..01e8695a2d 100644 --- a/git-compat-util.h +++ b/git-compat-util.h @@ -291,10 +291,12 @@ extern char *gitbasename(char *); #else #define NORETURN #define NORETURN_PTR +#ifndef __GNUC__ #ifndef __attribute__ #define __attribute__(x) #endif #endif +#endif /* The sentinel attribute is valid from gcc version 4.0 */ #if defined(__GNUC__) && (__GNUC__ >= 4) From 5d7fd6d06feb29acc9e6304a75b4e26eb23491c4 Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Mon, 7 Jul 2014 23:35:10 -0700 Subject: [PATCH 3/4] Run the perf test suite for profile feedback too Signed-off-by: Andi Kleen Signed-off-by: Junio C Hamano --- Makefile | 1 + 1 file changed, 1 insertion(+) diff --git a/Makefile b/Makefile index a9770ac476..ba64be9fb2 100644 --- a/Makefile +++ b/Makefile @@ -1647,6 +1647,7 @@ ifeq ($(filter all,$(MAKECMDGOALS)),all) all:: profile-clean $(MAKE) PROFILE=GEN all $(MAKE) PROFILE=GEN -j1 test + $(MAKE) PROFILE=GEN -j1 perf endif endif From 066dd2632acf11a348ff209b79f42c1a87a71fbb Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Mon, 7 Jul 2014 23:35:11 -0700 Subject: [PATCH 4/4] Fix profile feedback with -jN and add profile-fast Profile feedback always failed for me with -jN. The problem was that there was no implicit ordering between the profile generate stage and the profile use stage. So some objects in the later stage would be linked with profile generate objects, and fail due to the missing -lgcov. This adds a new profile target that implicitely enforces the correct ordering by using submakes. Plus a profile-install target to also install. This is also nicer to type that PROFILE=... Plus I always run the performance test suite now for the full profile run. In addition I also added a profile-fast / profile-fast-install target the only runs the performance test suite instead of the whole test suite. This significantly speeds up the profile build, which was totally dominated by test suite run time. However it may have less coverage of course. Signed-off-by: Andi Kleen Signed-off-by: Junio C Hamano --- INSTALL | 14 ++++++++++++-- Makefile | 21 +++++++++++++++++---- 2 files changed, 29 insertions(+), 6 deletions(-) diff --git a/INSTALL b/INSTALL index ba01e7421e..6ec7a24e1a 100644 --- a/INSTALL +++ b/INSTALL @@ -28,7 +28,7 @@ set up install paths (via config.mak.autogen), so you can write instead If you're willing to trade off (much) longer build time for a later faster git you can also do a profile feedback build with - $ make prefix=/usr PROFILE=BUILD all + $ make prefix=/usr profile # make prefix=/usr PROFILE=BUILD install This will run the complete test suite as training workload and then @@ -36,10 +36,20 @@ rebuild git with the generated profile feedback. This results in a git which is a few percent faster on CPU intensive workloads. This may be a good tradeoff for distribution packagers. +Alternatively you can run profile feedback only with the git benchmark +suite. This runs significantly faster than the full test suite, but +has less coverage: + + $ make prefix=/usr profile-fast + # make prefix=/usr PROFILE=BUILD install + Or if you just want to install a profile-optimized version of git into your home directory, you could run: - $ make PROFILE=BUILD install + $ make profile-install + +or + $ make profile-fast-install As a caveat: a profile-optimized build takes a *lot* longer since the git tree must be built twice, and in order for the profiling diff --git a/Makefile b/Makefile index ba64be9fb2..a760402370 100644 --- a/Makefile +++ b/Makefile @@ -1643,13 +1643,20 @@ SHELL = $(SHELL_PATH) all:: shell_compatibility_test ifeq "$(PROFILE)" "BUILD" -ifeq ($(filter all,$(MAKECMDGOALS)),all) -all:: profile-clean +all:: profile +endif + +profile:: profile-clean $(MAKE) PROFILE=GEN all $(MAKE) PROFILE=GEN -j1 test $(MAKE) PROFILE=GEN -j1 perf -endif -endif + $(MAKE) PROFILE=USE all + +profile-fast: profile-clean + $(MAKE) PROFILE=GEN all + $(MAKE) PROFILE=GEN -j1 perf + $(MAKE) PROFILE=USE all + all:: $(ALL_PROGRAMS) $(SCRIPT_LIB) $(BUILT_INS) $(OTHER_PROGRAMS) GIT-BUILD-OPTIONS ifneq (,$X) @@ -2336,6 +2343,12 @@ mergetools_instdir_SQ = $(subst ','\'',$(mergetools_instdir)) install_bindir_programs := $(patsubst %,%$X,$(BINDIR_PROGRAMS_NEED_X)) $(BINDIR_PROGRAMS_NO_X) +profile-install: profile + $(MAKE) install + +profile-fast-install: profile-fast + $(MAKE) install + install: all $(INSTALL) -d -m 755 '$(DESTDIR_SQ)$(bindir_SQ)' $(INSTALL) -d -m 755 '$(DESTDIR_SQ)$(gitexec_instdir_SQ)'