test_memcg_inotify_delete_file() and test_memcg_inotify_delete_dir() wait for IN_DELETE_SELF with a blocking read() on the inotify fd. On a kernel that does not send IN_DELETE_SELF for kernfs files and directories, the read() never returns and test_memcontrol hangs until it is killed by the kselftest timeout. The remaining tests do not run and no result is reported for the inotify tests.
Wait for the first event with poll() and a timeout. If IN_DELETE_SELF does not arrive in time, report it and fail the test instead of blocking, so that test_memcontrol completes and the remaining results are reported. Assisted-by: claude-opus-5-5 Signed-off-by: Sebastian Chlad <[email protected]> --- .../selftests/cgroup/test_memcontrol.c | 27 ++++++++++++++++--- 1 file changed, 23 insertions(+), 4 deletions(-) diff --git a/tools/testing/selftests/cgroup/test_memcontrol.c b/tools/testing/selftests/cgroup/test_memcontrol.c index 0ed82347044e..c00420acc9a1 100644 --- a/tools/testing/selftests/cgroup/test_memcontrol.c +++ b/tools/testing/selftests/cgroup/test_memcontrol.c @@ -11,6 +11,7 @@ #include <sys/types.h> #include <unistd.h> #include <sys/inotify.h> +#include <poll.h> #include <sys/socket.h> #include <sys/wait.h> #include <arpa/inet.h> @@ -1655,10 +1656,20 @@ static int test_memcg_oom_group_score_events(const char *root) return ret; } +#define INOTIFY_TIMEOUT_MS 5000 + static int read_event(int inotify_fd, int expected_event, int expected_wd) { + struct pollfd pfd = { .fd = inotify_fd, .events = POLLIN }; struct inotify_event event; ssize_t len = 0; + int ret; + + ret = poll(&pfd, 1, INOTIFY_TIMEOUT_MS); + if (ret == 0) + return -ETIMEDOUT; + if (ret < 0) + return -1; len = read(inotify_fd, &event, sizeof(event)); if (len < (ssize_t)sizeof(event)) @@ -1678,7 +1689,7 @@ static int test_memcg_inotify_delete_file(const char *root) { int ret = KSFT_FAIL; char *memcg = NULL; - int fd, wd; + int fd, wd, err; memcg = cg_name(root, "memcg_test_0"); @@ -1701,7 +1712,11 @@ static int test_memcg_inotify_delete_file(const char *root) free(memcg); memcg = NULL; - if (read_event(fd, IN_DELETE_SELF, wd)) + err = read_event(fd, IN_DELETE_SELF, wd); + if (err == -ETIMEDOUT) + fprintf(stderr, "no IN_DELETE_SELF event within %d ms\n", + INOTIFY_TIMEOUT_MS); + if (err) goto cleanup; if (read_event(fd, IN_IGNORED, wd)) @@ -1723,7 +1738,7 @@ static int test_memcg_inotify_delete_dir(const char *root) { int ret = KSFT_FAIL; char *memcg = NULL; - int fd, wd; + int fd, wd, err; memcg = cg_name(root, "memcg_test_0"); @@ -1746,7 +1761,11 @@ static int test_memcg_inotify_delete_dir(const char *root) free(memcg); memcg = NULL; - if (read_event(fd, IN_DELETE_SELF, wd)) + err = read_event(fd, IN_DELETE_SELF, wd); + if (err == -ETIMEDOUT) + fprintf(stderr, "no IN_DELETE_SELF event within %d ms\n", + INOTIFY_TIMEOUT_MS); + if (err) goto cleanup; if (read_event(fd, IN_IGNORED, wd)) -- 2.51.0
