From: Aneesh Kumar K.V Date: Tue, 14 Apr 2015 07:35:57 +0000 (+0530) Subject: powerpc/mm: Add trace point for tracking hash pte fault X-Git-Tag: omap-for-v4.2/fixes-rc1^2~139^2~54 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=cfcb3d80a28380ba027331eb548ba309c4b66559;p=pandora-kernel.git powerpc/mm: Add trace point for tracking hash pte fault This enables us to understand how many hash fault we are taking when running benchmarks. For ex: -bash-4.2# ./perf stat -e powerpc:hash_fault -e page-faults /tmp/ebizzy.ppc64 -S 30 -P -n 1000 ... Performance counter stats for '/tmp/ebizzy.ppc64 -S 30 -P -n 1000': 1,10,04,075 powerpc:hash_fault 1,10,03,429 page-faults 30.865978991 seconds time elapsed NOTE: The impact of the tracepoint was not noticeable when running test. It was within the run-time variance of the test. For ex: without-patch: -------------- Performance counter stats for './a.out 3000 300': 643 page-faults # 0.089 M/sec 7.236562 task-clock (msec) # 0.928 CPUs utilized 2,179,213 stalled-cycles-frontend # 0.00% frontend cycles idle 17,174,367 stalled-cycles-backend # 0.00% backend cycles idle 0 context-switches # 0.000 K/sec 0.007794658 seconds time elapsed And with-patch: --------------- Performance counter stats for './a.out 3000 300': 643 page-faults # 0.089 M/sec 7.233746 task-clock (msec) # 0.921 CPUs utilized 0 context-switches # 0.000 K/sec 0.007854876 seconds time elapsed Performance counter stats for './a.out 3000 300': 643 page-faults # 0.087 M/sec 649 powerpc:hash_fault # 0.087 M/sec 7.430376 task-clock (msec) # 0.938 CPUs utilized 2,347,174 stalled-cycles-frontend # 0.00% frontend cycles idle 17,524,282 stalled-cycles-backend # 0.00% backend cycles idle 0 context-switches # 0.000 K/sec 0.007920284 seconds time elapsed Signed-off-by: Aneesh Kumar K.V Signed-off-by: Michael Ellerman --- Reading git-diff-tree failed