@@ -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,
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/vm/ksm_tests.c | 37 ++++++++++++++++++++++++-- 1 file changed, 35 insertions(+), 2 deletions(-)