From: Arnaldo Carvalho de Melo Date: Thu, 7 Jan 2016 12:54:56 +0000 (-0300) Subject: perf tests: No need to set attr.sample_freq in the perf time to TSC test X-Git-Tag: Ubuntu-5.4-5.4.0-11.14~11011^2^2~27 X-Git-Url: https://git.proxmox.com/?a=commitdiff_plain;h=4f4ba0e6afac4b181471f5f12bd87294bd8807f6;p=mirror_ubuntu-focal-kernel.git perf tests: No need to set attr.sample_freq in the perf time to TSC test We were asking for a 4kHz sample_freq, making the test fail needlessly when the system reduced /proc/sys/kernel/perf_event_max_sample_rate below that. In this test we only look at the PERF_SAMPLE_TIME fields in PERF_RECORD_ meta events, no need to set sample_freq. Thanks to Namhyung for suggesting that max_sample_rate could be the reason for the test failure, seeing the 'perf test -vv' output I sent. Before: # echo 1000 > /proc/sys/kernel/perf_event_max_sample_rate # perf test TSC 45: Test converting perf time to TSC : FAILED! After: # perf test TSC 45: Test converting perf time to TSC : Ok # cat /proc/sys/kernel/perf_event_max_sample_rate 1000 Cc: Adrian Hunter Cc: David Ahern Cc: Jiri Olsa Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Wang Nan Link: http://lkml.kernel.org/n/tip-lcob05qhawkuvsyuu9g1fld5@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- diff --git a/tools/perf/arch/x86/tests/perf-time-to-tsc.c b/tools/perf/arch/x86/tests/perf-time-to-tsc.c index a289aa8a083a..9d29ee283ac5 100644 --- a/tools/perf/arch/x86/tests/perf-time-to-tsc.c +++ b/tools/perf/arch/x86/tests/perf-time-to-tsc.c @@ -41,7 +41,6 @@ int test__perf_time_to_tsc(int subtest __maybe_unused) .mmap_pages = UINT_MAX, .user_freq = UINT_MAX, .user_interval = ULLONG_MAX, - .freq = 4000, .target = { .uses_mmap = true, },