Currently, ksm_tests operates "merge_across_nodes" with NUMA either enabled or disabled. In a system with NUMA disabled, these operations will fail and output a misleading report given "merge_across_nodes" does not exist in sysfs:
---------------------------- running ./ksm_tests -M -p 10 ---------------------------- f /sys/kernel/mm/ksm/merge_across_nodes fopen: No such file or directory Cannot save default tunables [FAIL] ----------------------
So check numa_available() before those operations to skip them if NUMA is disabled.
Signed-off-by: Patrick Wang patrick.wang.shcn@gmail.com --- tools/testing/selftests/vm/ksm_tests.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-)
diff --git a/tools/testing/selftests/vm/ksm_tests.c b/tools/testing/selftests/vm/ksm_tests.c index fd85f15869d1..2fcf24312da8 100644 --- a/tools/testing/selftests/vm/ksm_tests.c +++ b/tools/testing/selftests/vm/ksm_tests.c @@ -221,7 +221,8 @@ static bool assert_ksm_pages_count(long dupl_page_count) static int ksm_save_def(struct ksm_sysfs *ksm_sysfs) { if (ksm_read_sysfs(KSM_FP("max_page_sharing"), &ksm_sysfs->max_page_sharing) || - ksm_read_sysfs(KSM_FP("merge_across_nodes"), &ksm_sysfs->merge_across_nodes) || + numa_available() ? 0 : + ksm_read_sysfs(KSM_FP("merge_across_nodes"), &ksm_sysfs->merge_across_nodes) || ksm_read_sysfs(KSM_FP("sleep_millisecs"), &ksm_sysfs->sleep_millisecs) || ksm_read_sysfs(KSM_FP("pages_to_scan"), &ksm_sysfs->pages_to_scan) || ksm_read_sysfs(KSM_FP("run"), &ksm_sysfs->run) || @@ -236,7 +237,8 @@ static int ksm_save_def(struct ksm_sysfs *ksm_sysfs) static int ksm_restore(struct ksm_sysfs *ksm_sysfs) { if (ksm_write_sysfs(KSM_FP("max_page_sharing"), ksm_sysfs->max_page_sharing) || - ksm_write_sysfs(KSM_FP("merge_across_nodes"), ksm_sysfs->merge_across_nodes) || + numa_available() ? 0 : + ksm_write_sysfs(KSM_FP("merge_across_nodes"), ksm_sysfs->merge_across_nodes) || ksm_write_sysfs(KSM_FP("pages_to_scan"), ksm_sysfs->pages_to_scan) || ksm_write_sysfs(KSM_FP("run"), ksm_sysfs->run) || ksm_write_sysfs(KSM_FP("sleep_millisecs"), ksm_sysfs->sleep_millisecs) || @@ -720,7 +722,8 @@ int main(int argc, char *argv[])
if (ksm_write_sysfs(KSM_FP("run"), 2) || ksm_write_sysfs(KSM_FP("sleep_millisecs"), 0) || - ksm_write_sysfs(KSM_FP("merge_across_nodes"), 1) || + numa_available() ? 0 : + ksm_write_sysfs(KSM_FP("merge_across_nodes"), 1) || ksm_write_sysfs(KSM_FP("pages_to_scan"), page_count)) return KSFT_FAIL;