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

[Athira Rajeev <atrajeev@linux.vnet.ibm.com>]

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 <atrajeev@linux.vnet.ibm.com>
---
 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