From 67c1e4a53b17894e6a24f95057cc374c4be051cb Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Mon, 11 Nov 2013 16:33:18 -0300 Subject: [PATCH] perf tests: Use lower sample_freq in sw clock event period test We were using it at 10 kHz, which doesn't work in machines where somehow the max freq was auto reduced by the kernel: [root@ssdandy ~]# perf test 19 19: Test software clock events have valid period values : FAILED! [root@ssdandy ~]# perf test -v 19 19: Test software clock events have valid period values : --- start --- Couldn't open evlist: Invalid argument ---- end ---- Test software clock events have valid period values: FAILED! [root@ssdandy ~]# [root@ssdandy ~]# cat /proc/sys/kernel/perf_event_max_sample_rate 7000 Reducing it to 500 Hz should be good enough for this test and also shouldn't affect what it is testing. But warn the user if it fails, informing the knob and the freq tried. Cc: Adrian Hunter Cc: David Ahern Cc: Frederic Weisbecker Cc: Jiri Olsa Cc: Mike Galbraith Cc: Namhyung Kim Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Stephane Eranian Link: http://lkml.kernel.org/n/tip-548rhj1uo6xbwnxa95kw3hqe@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/tests/sw-clock.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/tools/perf/tests/sw-clock.c b/tools/perf/tests/sw-clock.c index ed777728dfe7..93a7139ff5f7 100644 --- a/tools/perf/tests/sw-clock.c +++ b/tools/perf/tests/sw-clock.c @@ -34,7 +34,7 @@ static int __test__sw_clock_freq(enum perf_sw_ids clock_id) .freq = 1, }; - attr.sample_freq = 10000; + attr.sample_freq = 500; evlist = perf_evlist__new(); if (evlist == NULL) { @@ -58,8 +58,11 @@ static int __test__sw_clock_freq(enum perf_sw_ids clock_id) } if (perf_evlist__open(evlist)) { + const char *knob = "/proc/sys/kernel/perf_event_max_sample_rate"; + err = -errno; - pr_debug("Couldn't open evlist: %s\n", strerror(errno)); + pr_debug("Couldn't open evlist: %s\nHint: check %s, using %" PRIu64 " in this test.\n", + strerror(errno), knob, (u64)attr.sample_freq); goto out_delete_maps; } -- 2.39.5