Commit-ID: 9ea811973d49a1df0be04ff6e4df449e4fca4fb5 Gitweb: http://git.kernel.org/tip/9ea811973d49a1df0be04ff6e4df449e4fca4fb5 Author: Jan Beulich <JBeulich@xxxxxxxx> AuthorDate: Wed, 18 Jan 2012 13:28:13 +0000 Committer: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> CommitDate: Tue, 24 Jan 2012 19:50:19 -0200 perf bench: Make "default" memcpy() selection actually use glibc's implementation Since arch/x86/lib/memcpy_64.S implements not only __memcpy, but also memcpy, without further precautions this function will get chose by the static linker for resolving all references, and hence the "default" measurement didn't really measure anything else than the "x86-64-unrolled" one. Fix this by renaming (through the pre-processor) the conflicting symbol. On my Westmere system, the glibc variant turns out to require about 4% less instructions, but 15% more cycles for the default 1Mb block size measured. Cc: Ingo Molnar <mingo@xxxxxxx> Cc: Paul Mackerras <paulus@xxxxxxxxx> Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> Link: http://lkml.kernel.org/r/4F16D6FD020000780006D72F@xxxxxxxxxxxxxxxxxxxx Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx> Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> --- tools/perf/bench/mem-memcpy-x86-64-asm.S | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/tools/perf/bench/mem-memcpy-x86-64-asm.S b/tools/perf/bench/mem-memcpy-x86-64-asm.S index a57b66e..384b607 100644 --- a/tools/perf/bench/mem-memcpy-x86-64-asm.S +++ b/tools/perf/bench/mem-memcpy-x86-64-asm.S @@ -1,2 +1,2 @@ - +#define memcpy MEMCPY /* don't hide glibc's memcpy() */ #include "../../../arch/x86/lib/memcpy_64.S" -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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