[PATCH] perf test: Fix test 21 for s390x

[Thomas Richter <tmricht@linux.vnet.ibm.com>]

Test case 21 (Number of exit events of a simple workload) fails
on s390x. The reason is the invalid sample frequency supplied for
this test. On s390x the minimum sample frequency is much higher
(see output of /proc/service_levels:

[root@s35lp76 linux-devel]# cat /proc/service_levels 
CPU-MF: Counter facility: version=3.5 authorization=002f
CPU-MF: Sampling facility: min_rate=18228 max_rate=170650536 cpu_speed=5208
...
[root@s35lp76 linux-devel]#
).

Supply a save sample frequency value for s390x to fix this.
The value will be adjusted by the s390x CPUMF frequency
convertion function to a value well below the
sysctl kernel.perf_event_max_sample_rate value.

Signed-off-by: Thomas Richter <tmricht@linux.vnet.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
---
 tools/perf/tests/task-exit.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/tools/perf/tests/task-exit.c b/tools/perf/tests/task-exit.c
index bc4a7344e274..1073670dd1f2 100644
--- a/tools/perf/tests/task-exit.c
+++ b/tools/perf/tests/task-exit.c
@@ -84,7 +84,11 @@ int test__task_exit(struct test *test __maybe_unused, int subtest __maybe_unused
 
 	evsel = perf_evlist__first(evlist);
 	evsel->attr.task = 1;
+#ifdef __s390x__
+	evsel->attr.sample_freq = 1000000;
+#else
 	evsel->attr.sample_freq = 1;
+#endif
 	evsel->attr.inherit = 0;
 	evsel->attr.watermark = 0;
 	evsel->attr.wakeup_events = 1;
-- 
2.13.4