Re: [PATCH V2 2/2] tools/perf/tests: Fix session topology test to skip the test in guest environment

[Michael Ellerman]

Athira Rajeev  writes:
> The session topology test fails in powerpc pSeries platform.
> Test logs:
> <<>>
> Session topology : FAILED!
> <<>>
>
> This testcases tests cpu topology by checking the core_id and
> socket_id stored in perf_env from perf session. The data from
> perf session is compared with the cpu topology information
> from "/sys/devices/system/cpu/cpuX/topology" like core_id,
> physical_package_id. In case of virtual environment, detail
> like physical_package_id is restricted to be exposed. Hence
> physical_package_id is set to -1. The testcase fails on such
> platforms since socket_id can't be fetched from topology info.
>
> Skip the testcase in powerpc for pSeries. Use the utility
> function "cpuinfo_field" to check platform from /proc/cpuinfo.

I don't think that's the right way to fix it.

If we ever had a "pseries" machine that did expose physical_package_id
then this test would continue to skip, even when it could succeed.

So if physical_package_id being -1 is the problem then you should skip
the test based on that.

cheers

[PATCH V2 2/2] tools/perf/tests: Fix session topology test to skip the test in guest environment

[Athira Rajeev]

The session topology test fails in powerpc pSeries platform.
Test logs:
<<>>
Session topology : FAILED!
<<>>

This testcases tests cpu topology by checking the core_id and
socket_id stored in perf_env from perf session. The data from
perf session is compared with the cpu topology information
from "/sys/devices/system/cpu/cpuX/topology" like core_id,
physical_package_id. In case of virtual environment, detail
like physical_package_id is restricted to be exposed. Hence
physical_package_id is set to -1. The testcase fails on such
platforms since socket_id can't be fetched from topology info.

Skip the testcase in powerpc for pSeries. Use the utility
function "cpuinfo_field" to check platform from /proc/cpuinfo.

Results:

 After the patch:
 
 # ./perf test 41
 41: Session topology  : Skip

Signed-off-by: Athira Rajeev 
---
 tools/perf/tests/topology.c | 17 +
 1 file changed, 17 insertions(+)

diff --git a/tools/perf/tests/topology.c b/tools/perf/tests/topology.c
index ee1e3dcbc0bd..036143928023 100644
--- a/tools/perf/tests/topology.c
+++ b/tools/perf/tests/topology.c
@@ -109,6 +109,23 @@ static int check_cpu_topology(char *path, struct 
perf_cpu_map *map)
&& strncmp(session->header.env.arch, "aarch64", 7))
return TEST_SKIP;
 
+   /*
+* In powerpc pSeries platform, not all the topology information
+* are exposed via sysfs. Due to restriction, detail like
+* physical_package_id will be set to -1. Hence skip this
+* test for pSeries.
+*/
+   if (strncmp(session->header.env.arch, "powerpc", 7)) {
+   char *cpuinfo_platform = NULL;
+
+   cpuinfo_platform = cpuinfo_field("platform");
+   if (cpuinfo_platform && !strcmp(cpuinfo_platform, "pSeries")) {
+   free(cpuinfo_platform);
+   return TEST_SKIP;
+   }
+   free(cpuinfo_platform);
+   }
+
TEST_ASSERT_VAL("Session header CPU map not set", 
session->header.env.cpu);
 
for (i = 0; i < session->header.env.nr_cpus_avail; i++) {
-- 
2.35.1