On 11/11/13 22:22, Arnaldo Carvalho de Melo wrote: > From: Arnaldo Carvalho de Melo <a...@redhat.com> > > 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.
Doesn't work for me: ./perf test -v 19 19: Test software clock events have valid period values : --- start --- mmap size 528384B mmap size 528384B All (0) samples have period value of 1! ---- end ---- Test software clock events have valid period values: FAILED! But this fixes it: diff --git a/tools/perf/tests/sw-clock.c b/tools/perf/tests/sw-clock.c index 93a7139..6664a7c 100644 --- a/tools/perf/tests/sw-clock.c +++ b/tools/perf/tests/sw-clock.c @@ -9,7 +9,7 @@ #include "util/cpumap.h" #include "util/thread_map.h" -#define NR_LOOPS 1000000 +#define NR_LOOPS 10000000 /* * This test will open software clock events (cpu-clock, task-clock) > > Cc: Adrian Hunter <adrian.hun...@intel.com> > Cc: David Ahern <dsah...@gmail.com> > Cc: Frederic Weisbecker <fweis...@gmail.com> > Cc: Jiri Olsa <jo...@redhat.com> > Cc: Mike Galbraith <efa...@gmx.de> > Cc: Namhyung Kim <namhy...@kernel.org> > Cc: Paul Mackerras <pau...@samba.org> > Cc: Peter Zijlstra <pet...@infradead.org> > Cc: Stephane Eranian <eran...@google.com> > Link: http://lkml.kernel.org/n/tip-548rhj1uo6xbwnxa95kw3...@git.kernel.org > Signed-off-by: Arnaldo Carvalho de Melo <a...@redhat.com> > --- > 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; > } > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
