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.
Before:
# perf test -vv dummy
23: Test using a dummy software event to keep tracking :
--- start ---
test child forked, pid 32421
------------------------------------------------------------
perf_event_attr:
type 1
size 112
config 0x9
{ sample_period, sample_freq } 4000
sample_type IP|TID|ID|PERIOD
<SNIP>
sys_perf_event_open failed, error -22
Unable to open dummy and cycles event
test child finished with -2
---- end ----
Test using a dummy software event to keep tracking: Skip
#
[root@zoo ~]# cat /proc/sys/kernel/perf_event_max_sample_rate
1000
After:
[root@zoo ~]# perf test dummy
23: Test using a dummy software event to keep tracking : Ok
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-487iquegrs2379e5n0pi0tcp@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
239849dde3