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Diffstat (limited to 'tools/testing/selftests/resctrl/resctrlfs.c')
-rw-r--r--tools/testing/selftests/resctrl/resctrlfs.c32
1 files changed, 32 insertions, 0 deletions
diff --git a/tools/testing/selftests/resctrl/resctrlfs.c b/tools/testing/selftests/resctrl/resctrlfs.c
index dc7ce3cbdb27..195f04c4d158 100644
--- a/tools/testing/selftests/resctrl/resctrlfs.c
+++ b/tools/testing/selftests/resctrl/resctrlfs.c
@@ -957,3 +957,35 @@ unsigned int count_bits(unsigned long n)
return count;
}
+
+/**
+ * snc_kernel_support - Check for existence of mon_sub_L3_00 file that indicates
+ * SNC resctrl support on the kernel side.
+ *
+ * Return: 0 if not supported, 1 if SNC is disabled or SNC discovery is
+ * unreliable or SNC is both enabled and supported.
+ */
+int snc_kernel_support(void)
+{
+ char node_path[PATH_MAX];
+ struct stat statbuf;
+ int ret;
+
+ ret = snc_nodes_per_l3_cache();
+ /*
+ * If SNC is disabled then its kernel support isn't important. If SNC
+ * got disabled because the discovery process was unreliable the
+ * snc_unreliable variable was set. It can be used to verify the SNC
+ * discovery reliability elsewhere in the selftest.
+ */
+ if (ret == 1)
+ return ret;
+
+ snprintf(node_path, sizeof(node_path), "%s/%s", RESCTRL_PATH,
+ "mon_data/mon_L3_00/mon_sub_L3_00");
+
+ if (!stat(node_path, &statbuf))
+ return 1;
+
+ return 0;
+}