1 files changed, 20 insertions, 19 deletions

diff --git a/tools/testing/selftests/cgroup/test_kmem.c b/tools/testing/selftests/cgroup/test_kmem.c
index 96693d8772be..eeabd34bf083 100644
--- a/tools/testing/selftests/cgroup/test_kmem.c
+++ b/tools/testing/selftests/cgroup/test_kmem.c
@@ -14,7 +14,7 @@
 #include <sys/sysinfo.h>
 #include <pthread.h>
 
-#include "../kselftest.h"
+#include "kselftest.h"
 #include "cgroup_util.h"
 
 
@@ -26,6 +26,7 @@
  */
 #define MAX_VMSTAT_ERROR (4096 * 64 * get_nprocs())
 
+#define KMEM_DEAD_WAIT_RETRIES        80
 
 static int alloc_dcache(const char *cgroup, void *arg)
 {
@@ -306,8 +307,7 @@ static int test_kmem_dead_cgroups(const char *root)
 {
 	int ret = KSFT_FAIL;
 	char *parent;
-	long dead;
-	int i;
+	long dead = -1;
 
 	parent = cg_name(root, "kmem_dead_cgroups_test");
 	if (!parent)
@@ -322,19 +322,19 @@ static int test_kmem_dead_cgroups(const char *root)
 	if (cg_run_in_subcgroups(parent, alloc_dcache, (void *)100, 30))
 		goto cleanup;
 
-	for (i = 0; i < 5; i++) {
-		dead = cg_read_key_long(parent, "cgroup.stat",
-					"nr_dying_descendants ");
-		if (dead == 0) {
-			ret = KSFT_PASS;
-			break;
-		}
-		/*
-		 * Reclaiming cgroups might take some time,
-		 * let's wait a bit and repeat.
-		 */
-		sleep(1);
-	}
+	/*
+	 * Allow up to ~8s for reclaim of dying descendants to complete.
+	 * This is a generous upper bound derived from stress testing, not
+	 * from a specific kernel constant, and can be adjusted if reclaim
+	 * behavior changes in the future.
+	 */
+	dead = cg_read_key_long_poll(parent, "cgroup.stat",
+					"nr_dying_descendants ", 0, KMEM_DEAD_WAIT_RETRIES,
+					DEFAULT_WAIT_INTERVAL_US);
+	if (dead)
+		goto cleanup;
+
+	ret = KSFT_PASS;
 
 cleanup:
 	cg_destroy(parent);
@@ -418,8 +418,10 @@ struct kmem_test {
 int main(int argc, char **argv)
 {
 	char root[PATH_MAX];
-	int i, ret = EXIT_SUCCESS;
+	int i;
 
+	ksft_print_header();
+	ksft_set_plan(ARRAY_SIZE(tests));
 	if (cg_find_unified_root(root, sizeof(root), NULL))
 		ksft_exit_skip("cgroup v2 isn't mounted\n");
 
@@ -443,11 +445,10 @@ int main(int argc, char **argv)
 			ksft_test_result_skip("%s\n", tests[i].name);
 			break;
 		default:
-			ret = EXIT_FAILURE;
 			ksft_test_result_fail("%s\n", tests[i].name);
 			break;
 		}
 	}
 
-	return ret;
+	ksft_finished();
 }