| Message ID | 20170430161600.15845-1-rabin@rab.in (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
2017-05-01 1:16 GMT+09:00 Rabin Vincent <rabin@rab.in>: > Evaluate LDFLAGS_BUILD_ID (which involves invoking the compiler) only > once instead of over and over. > > This provides a ~20% reduction in null build time with x86 allnoconfig: > > $ make allnoconfig && make -j8 > $ perf stat -r5 -e sched:sched_process_exec make -j8 > - 2 119 sched:sched_process_exec > + 1 878 sched:sched_process_exec > > - 1,238817018 seconds time elapsed > + 0,971020553 seconds time elapsed > > Signed-off-by: Rabin Vincent <rabin@rab.in> Applied to linux-kbuild/kbuild. Thanks!
diff --git a/Makefile b/Makefile index 779302695453..c78a266594c1 100644 --- a/Makefile +++ b/Makefile @@ -815,7 +815,7 @@ KBUILD_AFLAGS += $(ARCH_AFLAGS) $(KAFLAGS) KBUILD_CFLAGS += $(ARCH_CFLAGS) $(KCFLAGS) # Use --build-id when available. -LDFLAGS_BUILD_ID = $(patsubst -Wl$(comma)%,%,\ +LDFLAGS_BUILD_ID := $(patsubst -Wl$(comma)%,%,\ $(call cc-ldoption, -Wl$(comma)--build-id,)) KBUILD_LDFLAGS_MODULE += $(LDFLAGS_BUILD_ID) LDFLAGS_vmlinux += $(LDFLAGS_BUILD_ID)
Evaluate LDFLAGS_BUILD_ID (which involves invoking the compiler) only once instead of over and over. This provides a ~20% reduction in null build time with x86 allnoconfig: $ make allnoconfig && make -j8 $ perf stat -r5 -e sched:sched_process_exec make -j8 - 2 119 sched:sched_process_exec + 1 878 sched:sched_process_exec - 1,238817018 seconds time elapsed + 0,971020553 seconds time elapsed Signed-off-by: Rabin Vincent <rabin@rab.in> --- Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)