This adds the -G flag to the ksm_tests to query if prctl has been used to enable ksm merging.
Signed-off-by: Stefan Roesch shr@devkernel.io --- tools/testing/selftests/mm/ksm_tests.c | 37 ++++++++++++++++++++++++-- 1 file changed, 35 insertions(+), 2 deletions(-)
diff --git a/tools/testing/selftests/mm/ksm_tests.c b/tools/testing/selftests/mm/ksm_tests.c index 386a0929c8a3..9667cb3b8c6a 100644 --- a/tools/testing/selftests/mm/ksm_tests.c +++ b/tools/testing/selftests/mm/ksm_tests.c @@ -45,6 +45,7 @@ enum ksm_merge_type { enum ksm_test_name { CHECK_KSM_MERGE, CHECK_KSM_UNMERGE, + CHECK_KSM_GET_MERGE_TYPE, CHECK_KSM_ZERO_PAGE_MERGE, CHECK_KSM_NUMA_MERGE, KSM_MERGE_TIME, @@ -124,7 +125,8 @@ static void print_help(void) " -D evaluate unmerging time and speed when disabling KSM.\n" " For this test, the size of duplicated memory area (in MiB)\n" " must be provided using -s option\n" - " -C evaluate the time required to break COW of merged pages.\n\n"); + " -C evaluate the time required to break COW of merged pages.\n" + " -G query merge mode\n\n");
printf(" -a: specify the access protections of pages.\n" " <prot> must be of the form [rwx].\n" @@ -323,6 +325,31 @@ static int check_ksm_merge(int merge_type, int mapping, int prot, return KSFT_FAIL; }
+static int check_ksm_get_merge_type(void) +{ + if (prctl(PR_SET_MEMORY_MERGE, 1)) { + perror("prctl set"); + return 1; + } + + int is_on = prctl(PR_GET_MEMORY_MERGE, 0); + + if (prctl(PR_SET_MEMORY_MERGE, 0)) { + perror("prctl set"); + return 1; + } + + int is_off = prctl(PR_GET_MEMORY_MERGE, 0); + + if (is_on && is_off) { + printf("OK\n"); + return KSFT_PASS; + } + + printf("Not OK\n"); + return KSFT_FAIL; +} + static int check_ksm_unmerge(int merge_type, int mapping, int prot, int timeout, size_t page_size) { void *map_ptr; @@ -733,7 +760,7 @@ int main(int argc, char *argv[]) bool merge_across_nodes = KSM_MERGE_ACROSS_NODES_DEFAULT; long size_MB = 0;
- while ((opt = getopt(argc, argv, "ha:p:l:z:m:s:t:MUZNPCHD")) != -1) { + while ((opt = getopt(argc, argv, "ha:p:l:z:m:s:t:GMUZNPCHD")) != -1) { switch (opt) { case 'a': prot = str_to_prot(optarg); @@ -792,6 +819,9 @@ int main(int argc, char *argv[]) case 'Z': test_name = CHECK_KSM_ZERO_PAGE_MERGE; break; + case 'G': + test_name = CHECK_KSM_GET_MERGE_TYPE; + break; case 'N': test_name = CHECK_KSM_NUMA_MERGE; break; @@ -841,6 +871,9 @@ int main(int argc, char *argv[]) ret = check_ksm_unmerge(merge_type, MAP_PRIVATE | MAP_ANONYMOUS, prot, ksm_scan_limit_sec, page_size); break; + case CHECK_KSM_GET_MERGE_TYPE: + ret = check_ksm_get_merge_type(); + break; case CHECK_KSM_ZERO_PAGE_MERGE: ret = check_ksm_zero_page_merge(merge_type, MAP_PRIVATE | MAP_ANONYMOUS, prot, page_count, ksm_scan_limit_sec, use_zero_pages,