alistair23-linux/tools/perf/bench
Andi Kleen a198996c7a perf bench: Fix memcpy benchmark for large sizes
The glibc calloc() function has an optimization to not explicitely
memset() very large calloc allocations that just came from mmap(),
because they are known to be zero.

This could result in the perf memcpy benchmark reading only from
the zero page, which gives unrealistic results.

Always call memset explicitly on the source area to avoid this problem.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Hitoshi Mitake <h.mitake@gmail.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Link: http://lkml.kernel.org/n/tip-pzz2qrdq9eymxda0y8yxdn33@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-07-22 12:41:56 -03:00
..
bench.h perf tools: Fix LIBNUMA build with glibc 2.12 and older. 2013-03-14 08:06:21 -03:00
mem-memcpy-arch.h perf bench: Add feature that measures the performance of the arch/x86/lib/memcpy_64.S memcpy routines via 'perf bench mem' 2010-11-26 08:15:57 +01:00
mem-memcpy-x86-64-asm-def.h perf bench: Also allow measuring alternative memcpy implementations 2012-01-24 19:51:01 -02:00
mem-memcpy-x86-64-asm.S Merge branch 'perf/urgent' into perf/core 2012-02-06 19:11:02 -02:00
mem-memcpy.c perf bench: Fix memcpy benchmark for large sizes 2013-07-22 12:41:56 -03:00
mem-memset-arch.h perf bench: Also allow measuring memset() 2012-01-24 20:25:32 -02:00
mem-memset-x86-64-asm-def.h perf bench: Also allow measuring memset() 2012-01-24 20:25:32 -02:00
mem-memset-x86-64-asm.S perf tool: Fix perf stack to non executable on x86_64 2012-02-06 19:14:17 -02:00
mem-memset.c perf bench: Fix memory allocation fail check in mem{set,cpy} workloads 2013-07-08 17:35:40 -03:00
numa.c perf: Add 'perf bench numa mem' NUMA performance measurement suite 2013-01-30 10:35:36 -03:00
sched-messaging.c perf tools: Use __maybe_used for unused variables 2012-09-11 12:19:15 -03:00
sched-pipe.c perf tools: Use __maybe_used for unused variables 2012-09-11 12:19:15 -03:00