diff options
author | Andi Kleen <ak@linux.intel.com> | 2013-07-18 15:33:46 -0700 |
---|---|---|
committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2013-07-22 12:41:56 -0300 |
commit | a198996c7afae0097c67a61851f19863e59697b2 (patch) | |
tree | f62c96cb1b67ae9bbc465134bc9e66180ff07092 /tools/perf/util/callchain.c | |
parent | 2b821cce1c950cead081d779db0dda680192c4bd (diff) | |
download | op-kernel-dev-a198996c7afae0097c67a61851f19863e59697b2.zip op-kernel-dev-a198996c7afae0097c67a61851f19863e59697b2.tar.gz |
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>
Diffstat (limited to 'tools/perf/util/callchain.c')
0 files changed, 0 insertions, 0 deletions