Add tests for both L2 and L3 CAT to verify the return values
generated by writing non-contiguous CBMs don't contradict the
reported non-contiguous support information.
Use a logical XOR to confirm return value of write_schemata() and
non-contiguous CBMs support information match.
Signed-off-by: Maciej Wieczor-Retman <maciej.wieczor-retman@xxxxxxxxx>
Reviewed-by: Reinette Chatre <reinette.chatre@xxxxxxxxx>
---
Changelog v6:
- Change ret to int type for proper error returns. (Reinette)
- Add a check for bit_center variable to verify the CBM width isn't too
small. Also add a comment to explain the check. (Reinette)
Changelog v5:
- Add Reinette's reviewed-by tag.
- Make 0xf UL in case the CBMs get bigger in the future. (Ilpo)
Changelog v4:
- Return failure instead of error on check of cpuid against sparse_masks
and on contiguous write_schemata fail. (Reinette)
Changelog v3:
- Roll back __cpuid_count part. (Reinette)
- Update function name to read sparse_masks file.
- Roll back get_cache_level() changes.
- Add ksft_print_msg() to contiguous schemata write error handling
(Reinette).
Changelog v2:
- Redo the patch message. (Ilpo)
- Tidy up __cpuid_count calls. (Ilpo)
- Remove redundant AND in noncont_mask calculations (Ilpo)
- Fix bit_center offset.
- Add newline before function return. (Ilpo)
- Group non-contiguous tests with CAT tests. (Ilpo)
- Use a helper for reading sparse_masks file. (Ilpo)
- Make get_cache_level() available in other source files. (Ilpo)
tools/testing/selftests/resctrl/cat_test.c | 89 +++++++++++++++++++
tools/testing/selftests/resctrl/resctrl.h | 2 +
.../testing/selftests/resctrl/resctrl_tests.c | 2 +
3 files changed, 93 insertions(+)
diff --git a/tools/testing/selftests/resctrl/cat_test.c b/tools/testing/selftests/resctrl/cat_test.c
index 39fc9303b8e8..4cb991be8e31 100644
--- a/tools/testing/selftests/resctrl/cat_test.c
+++ b/tools/testing/selftests/resctrl/cat_test.c
@@ -294,6 +294,79 @@ static int cat_run_test(const struct resctrl_test *test, const struct user_param
return ret;
}
+static int noncont_cat_run_test(const struct resctrl_test *test,
+ const struct user_params *uparams)
+{
+ unsigned long full_cache_mask, cont_mask, noncont_mask;
+ unsigned int eax, ebx, ecx, edx, sparse_masks;
+ int bit_center, ret;
+ char schemata[64];
+
+ /* Check to compare sparse_masks content to CPUID output. */
+ ret = resource_info_unsigned_get(test->resource, "sparse_masks", &sparse_masks);
+ if (ret)
+ return ret;
+
+ if (!strcmp(test->resource, "L3"))
+ __cpuid_count(0x10, 1, eax, ebx, ecx, edx);
+ else if (!strcmp(test->resource, "L2"))
+ __cpuid_count(0x10, 2, eax, ebx, ecx, edx);
+ else
+ return -EINVAL;
+
+ if (sparse_masks != ((ecx >> 3) & 1)) {
+ ksft_print_msg("CPUID output doesn't match 'sparse_masks' file content!\n");
+ return 1;
+ }
+
+ /* Write checks initialization. */
+ ret = get_full_cbm(test->resource, &full_cache_mask);
+ if (ret < 0)
+ return ret;
+ bit_center = count_bits(full_cache_mask) / 2;
+
+ /*
+ * The bit_center needs to be at least 3 to properly calculate the CBM
+ * hole in the noncont_mask. If it's smaller return an error since the
+ * cache mask is too short and that shouldn't happen.
+ */
+ if (bit_center < 3)
+ return -EINVAL;
+ cont_mask = full_cache_mask >> bit_center;
+
+ /* Contiguous mask write check. */
+ snprintf(schemata, sizeof(schemata), "%lx", cont_mask);
+ ret = write_schemata("", schemata, uparams->cpu, test->resource);
+ if (ret) {
+ ksft_print_msg("Write of contiguous CBM failed\n");
+ return 1;
+ }
+
+ /*
+ * Non-contiguous mask write check. CBM has a 0xf hole approximately in the middle.
+ * Output is compared with support information to catch any edge case errors.
+ */
+ noncont_mask = ~(0xfUL << (bit_center - 2)) & full_cache_mask;
+ snprintf(schemata, sizeof(schemata), "%lx", noncont_mask);
+ ret = write_schemata("", schemata, uparams->cpu, test->resource);
+ if (ret && sparse_masks)
+ ksft_print_msg("Non-contiguous CBMs supported but write of non-contiguous CBM failed\n");
+ else if (ret && !sparse_masks)
+ ksft_print_msg("Non-contiguous CBMs not supported and write of non-contiguous CBM failed as expected\n");
+ else if (!ret && !sparse_masks)
+ ksft_print_msg("Non-contiguous CBMs not supported but write of non-contiguous CBM succeeded\n");
+
+ return !ret == !sparse_masks;
+}
+
+static bool noncont_cat_feature_check(const struct resctrl_test *test)
+{
+ if (!resctrl_resource_exists(test->resource))
+ return false;
+
+ return resource_info_file_exists(test->resource, "sparse_masks");
+}
+
struct resctrl_test l3_cat_test = {
.name = "L3_CAT",
.group = "CAT",
@@ -301,3 +374,19 @@ struct resctrl_test l3_cat_test = {
.feature_check = test_resource_feature_check,
.run_test = cat_run_test,
};
+
+struct resctrl_test l3_noncont_cat_test = {
+ .name = "L3_NONCONT_CAT",
+ .group = "CAT",
+ .resource = "L3",
+ .feature_check = noncont_cat_feature_check,
+ .run_test = noncont_cat_run_test,
+};
+
+struct resctrl_test l2_noncont_cat_test = {
+ .name = "L2_NONCONT_CAT",
+ .group = "CAT",
+ .resource = "L2",
+ .feature_check = noncont_cat_feature_check,
+ .run_test = noncont_cat_run_test,
+};
diff --git a/tools/testing/selftests/resctrl/resctrl.h b/tools/testing/selftests/resctrl/resctrl.h
index f434a6543b4f..2051bd135e0d 100644
--- a/tools/testing/selftests/resctrl/resctrl.h
+++ b/tools/testing/selftests/resctrl/resctrl.h
@@ -209,5 +209,7 @@ extern struct resctrl_test mbm_test;
extern struct resctrl_test mba_test;
extern struct resctrl_test cmt_test;
extern struct resctrl_test l3_cat_test;
+extern struct resctrl_test l3_noncont_cat_test;
+extern struct resctrl_test l2_noncont_cat_test;
#endif /* RESCTRL_H */
diff --git a/tools/testing/selftests/resctrl/resctrl_tests.c b/tools/testing/selftests/resctrl/resctrl_tests.c
index 3044179ee6e9..f3dc1b9696e7 100644
--- a/tools/testing/selftests/resctrl/resctrl_tests.c
+++ b/tools/testing/selftests/resctrl/resctrl_tests.c
@@ -19,6 +19,8 @@ static struct resctrl_test *resctrl_tests[] = {
&mba_test,
&cmt_test,
&l3_cat_test,
+ &l3_noncont_cat_test,
+ &l2_noncont_cat_test,
};
static int detect_vendor(void)
--
2.43.0
