[PATCH 4/4] selftests/resctrl: Skip the tests if iMC/UMC counters are unavailable

[Babu Moger <babu.moger@amd.com>]

Older systems do not support UMC (Unified Memory Controller) perf counters.
Skip the tests if the system does not support UMC counters.

Signed-off-by: Babu Moger <babu.moger@amd.com>
---
 tools/testing/selftests/resctrl/resctrl.h       |  1 +
 tools/testing/selftests/resctrl/resctrl_tests.c | 10 ++++++++++
 tools/testing/selftests/resctrl/resctrl_val.c   |  4 ++--
 3 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/resctrl/resctrl.h b/tools/testing/selftests/resctrl/resctrl.h
index a33f414f6019..5c2556af0649 100644
--- a/tools/testing/selftests/resctrl/resctrl.h
+++ b/tools/testing/selftests/resctrl/resctrl.h
@@ -116,5 +116,6 @@ int show_cache_info(unsigned long sum_llc_val, int no_of_bits,
 		    size_t cache_span, unsigned long max_diff,
 		    unsigned long max_diff_percent, unsigned long num_of_runs,
 		    bool platform, bool cmt);
+int get_number_of_mem_ctrls(void);
 
 #endif /* RESCTRL_H */
diff --git a/tools/testing/selftests/resctrl/resctrl_tests.c b/tools/testing/selftests/resctrl/resctrl_tests.c
index 231233b8d354..5423882529ec 100644
--- a/tools/testing/selftests/resctrl/resctrl_tests.c
+++ b/tools/testing/selftests/resctrl/resctrl_tests.c
@@ -98,6 +98,11 @@ static void run_mbm_test(const char * const *benchmark_cmd, int cpu_no)
 
 	ksft_print_msg("Starting MBM BW change ...\n");
 
+	if (get_number_of_mem_ctrls() < 0) {
+		ksft_test_result_skip("Unable find iMC/UMC counters!\n");
+		return;
+	}
+
 	if (test_prepare()) {
 		ksft_exit_fail_msg("Abnormal failure when preparing for the test\n");
 		return;
@@ -124,6 +129,11 @@ static void run_mba_test(const char * const *benchmark_cmd, int cpu_no)
 
 	ksft_print_msg("Starting MBA Schemata change ...\n");
 
+	if (get_number_of_mem_ctrls() < 0) {
+		ksft_test_result_skip("Unable find iMC/UMC counters!\n");
+		return;
+	}
+
 	if (test_prepare()) {
 		ksft_exit_fail_msg("Abnormal failure when preparing for the test\n");
 		return;
diff --git a/tools/testing/selftests/resctrl/resctrl_val.c b/tools/testing/selftests/resctrl/resctrl_val.c
index c5a4607aa9d9..68cee87c26ef 100644
--- a/tools/testing/selftests/resctrl/resctrl_val.c
+++ b/tools/testing/selftests/resctrl/resctrl_val.c
@@ -262,7 +262,7 @@ static int read_from_imc_dir(char *imc_dir, int count)
  *
  * Return: >= 0 on success. < 0 on failure.
  */
-static int get_number_of_mem_ctrls(void)
+int get_number_of_mem_ctrls(void)
 {
 	char imc_dir[512], *temp;
 	unsigned int count = 0;
@@ -323,7 +323,7 @@ static int get_number_of_mem_ctrls(void)
 		}
 		closedir(dp);
 		if (count == 0) {
-			perror("Unable find iMC counters!\n");
+			perror("Unable find iMC/UMC counters!\n");
 
 			return -1;
 		}
-- 
2.34.1