linux-kernel - [tip:perf/core] perf tests: No need to set attr.sample_freq for tracking !PERF_RECORD

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Date:	Sat, 9 Jan 2016 08:34:43 -0800
From:	tip-bot for Arnaldo Carvalho de Melo <tipbot@...or.com>
To:	linux-tip-commits@...r.kernel.org
Cc:	adrian.hunter@...el.com, wangnan0@...wei.com, namhyung@...nel.org,
	tglx@...utronix.de, acme@...hat.com, linux-kernel@...r.kernel.org,
	dsahern@...il.com, mingo@...nel.org, hpa@...or.com,
	jolsa@...hat.com
Subject: [tip:perf/core] perf tests:
  No need to set attr.sample_freq for tracking !PERF_RECORD_SAMPLE

Commit-ID:  239849dde350c9f7356974ca4f62171f50a2c86e
Gitweb:     http://git.kernel.org/tip/239849dde350c9f7356974ca4f62171f50a2c86e
Author:     Arnaldo Carvalho de Melo <acme@...hat.com>
AuthorDate: Thu, 7 Jan 2016 16:51:58 -0300
Committer:  Arnaldo Carvalho de Melo <acme@...hat.com>
CommitDate: Thu, 7 Jan 2016 16:51:58 -0300

perf tests: No need to set attr.sample_freq for tracking !PERF_RECORD_SAMPLE

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@...el.com>
Cc: David Ahern <dsahern@...il.com>
Cc: Jiri Olsa <jolsa@...hat.com>
Cc: Namhyung Kim <namhyung@...nel.org>
Cc: Wang Nan <wangnan0@...wei.com>
Link: http://lkml.kernel.org/n/tip-487iquegrs2379e5n0pi0tcp@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@...hat.com>
---
 tools/perf/tests/keep-tracking.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/tools/perf/tests/keep-tracking.c b/tools/perf/tests/keep-tracking.c
index a337a6d..6158132 100644
--- a/tools/perf/tests/keep-tracking.c
+++ b/tools/perf/tests/keep-tracking.c
@@ -55,7 +55,6 @@ int test__keep_tracking(int subtest __maybe_unused)
 		.mmap_pages	     = UINT_MAX,
 		.user_freq	     = UINT_MAX,
 		.user_interval	     = ULLONG_MAX,
-		.freq		     = 4000,
 		.target		     = {
 			.uses_mmap   = true,
 		},