4 files changed, 39 insertions, 13 deletions

diff --git a/tools/testing/selftests/resctrl/cat_test.c b/tools/testing/selftests/resctrl/cat_test.c
index 94cfdba5308d..f00b622c1460 100644
--- a/tools/testing/selftests/resctrl/cat_test.c
+++ b/tools/testing/selftests/resctrl/cat_test.c
@@ -290,8 +290,10 @@ static int cat_run_test(const struct resctrl_test *test, const struct user_param
 
 static bool arch_supports_noncont_cat(const struct resctrl_test *test)
 {
-	/* AMD always supports non-contiguous CBM. */
-	if (get_vendor() == ARCH_AMD)
+	unsigned int vendor_id = get_vendor();
+
+	/* AMD and Hygon always support non-contiguous CBM. */
+	if (vendor_id == ARCH_AMD || vendor_id == ARCH_HYGON)
 		return true;
 
 #if defined(__i386__) || defined(__x86_64__) /* arch */
diff --git a/tools/testing/selftests/resctrl/resctrl.h b/tools/testing/selftests/resctrl/resctrl.h
index 3c51bdac2dfa..afe635b6e48d 100644
--- a/tools/testing/selftests/resctrl/resctrl.h
+++ b/tools/testing/selftests/resctrl/resctrl.h
@@ -23,6 +23,7 @@
 #include <asm/unistd.h>
 #include <linux/perf_event.h>
 #include <linux/compiler.h>
+#include <linux/bits.h>
 #include "kselftest.h"
 
 #define MB			(1024 * 1024)
@@ -36,8 +37,9 @@
  * Define as bits because they're used for vendor_specific bitmask in
  * the struct resctrl_test.
  */
-#define ARCH_INTEL     1
-#define ARCH_AMD       2
+#define ARCH_INTEL	BIT(0)
+#define ARCH_AMD	BIT(1)
+#define ARCH_HYGON	BIT(2)
 
 #define END_OF_TESTS	1
 
@@ -163,7 +165,7 @@ extern int snc_unreliable;
 extern char llc_occup_path[1024];
 
 int snc_nodes_per_l3_cache(void);
-int get_vendor(void);
+unsigned int get_vendor(void);
 bool check_resctrlfs_support(void);
 int filter_dmesg(void);
 int get_domain_id(const char *resource, int cpu_no, int *domain_id);
diff --git a/tools/testing/selftests/resctrl/resctrl_tests.c b/tools/testing/selftests/resctrl/resctrl_tests.c
index 5154ffd821c4..dbcd5eea9fbc 100644
--- a/tools/testing/selftests/resctrl/resctrl_tests.c
+++ b/tools/testing/selftests/resctrl/resctrl_tests.c
@@ -23,16 +23,24 @@ static struct resctrl_test *resctrl_tests[] = {
 	&l2_noncont_cat_test,
 };
 
-static int detect_vendor(void)
+static unsigned int detect_vendor(void)
 {
-	FILE *inf = fopen("/proc/cpuinfo", "r");
-	int vendor_id = 0;
+	static unsigned int vendor_id;
+	static bool initialized;
 	char *s = NULL;
+	FILE *inf;
 	char *res;
 
-	if (!inf)
+	if (initialized)
 		return vendor_id;
 
+	inf = fopen("/proc/cpuinfo", "r");
+	if (!inf) {
+		vendor_id = 0;
+		initialized = true;
+		return vendor_id;
+	}
+
 	res = fgrep(inf, "vendor_id");
 
 	if (res)
@@ -42,18 +50,22 @@ static int detect_vendor(void)
 		vendor_id = ARCH_INTEL;
 	else if (s && !strcmp(s, ": AuthenticAMD\n"))
 		vendor_id = ARCH_AMD;
+	else if (s && !strcmp(s, ": HygonGenuine\n"))
+		vendor_id = ARCH_HYGON;
 
 	fclose(inf);
 	free(res);
+
+	initialized = true;
 	return vendor_id;
 }
 
-int get_vendor(void)
+unsigned int get_vendor(void)
 {
-	static int vendor = -1;
+	unsigned int vendor;
+
+	vendor = detect_vendor();
 
-	if (vendor == -1)
-		vendor = detect_vendor();
 	if (vendor == 0)
 		ksft_print_msg("Can not get vendor info...\n");
 
diff --git a/tools/testing/selftests/resctrl/resctrlfs.c b/tools/testing/selftests/resctrl/resctrlfs.c
index 195f04c4d158..b9c1bfb6cc02 100644
--- a/tools/testing/selftests/resctrl/resctrlfs.c
+++ b/tools/testing/selftests/resctrl/resctrlfs.c
@@ -243,6 +243,16 @@ int snc_nodes_per_l3_cache(void)
 		}
 		snc_mode = cache_cpus / node_cpus;
 
+		/*
+		 * On some platforms (e.g. Hygon),
+		 * cache_cpus < node_cpus, the calculated snc_mode is 0.
+		 *
+		 * Set snc_mode = 1 to indicate that SNC mode is not
+		 * supported on the platform.
+		 */
+		if (!snc_mode)
+			snc_mode = 1;
+
 		if (snc_mode > 1)
 			ksft_print_msg("SNC-%d mode discovered.\n", snc_mode);
 	}