The selftest noncont_cat_run_test fails on AMD with the warnings. Reason is, AMD supports non contiguous CBM masks but does not report it via CPUID.
Update noncont_cat_run_test to check for the vendor when verifying CPUID.
Fixes: ae638551ab64 ("selftests/resctrl: Add non-contiguous CBMs CAT test") Signed-off-by: Babu Moger babu.moger@amd.com --- v2: Moved the non contiguous verification to a new function arch_supports_noncont_cat.
v1: This was part of the series https://lore.kernel.org/lkml/cover.1708637563.git.babu.moger@amd.com/ Sending this as a separate fix per review comments. --- tools/testing/selftests/resctrl/cat_test.c | 32 +++++++++++++++------- 1 file changed, 22 insertions(+), 10 deletions(-)
diff --git a/tools/testing/selftests/resctrl/cat_test.c b/tools/testing/selftests/resctrl/cat_test.c index d4dffc934bc3..742782438ca3 100644 --- a/tools/testing/selftests/resctrl/cat_test.c +++ b/tools/testing/selftests/resctrl/cat_test.c @@ -288,11 +288,30 @@ static int cat_run_test(const struct resctrl_test *test, const struct user_param return ret; }
+static bool arch_supports_noncont_cat(const struct resctrl_test *test) +{ + unsigned int eax, ebx, ecx, edx; + + /* AMD always supports non-contiguous CBM. */ + if (get_vendor() == ARCH_AMD) + return true; + + /* Intel support for non-contiguous CBM needs to be discovered. */ + 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 false; + + return ((ecx >> 3) & 1); +} + 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; + unsigned int sparse_masks; int bit_center, ret; char schemata[64];
@@ -301,15 +320,8 @@ static int noncont_cat_run_test(const struct resctrl_test *test, 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"); + if (arch_supports_noncont_cat(test) != sparse_masks) { + ksft_print_msg("Hardware and kernel differ on non-contiguous CBM support!\n"); return 1; }