Re: [PATCH v1 2/2] Add selftests for pidfd polling

On Thu, Apr 25, 2019 at 03:00:10PM -0400, Joel Fernandes (Google) wrote:

+void *test_pidfd_poll_exec_thread(void *priv)

I think everything in this file can be static, there's this one and 3-4 below.

+int test_pidfd_poll_exec(int use_waitpid) +{

• int pid, pidfd = 0;
• int status, ret;
• pthread_t t1;
• time_t prog_start = time(NULL);
• const char *test_name = "pidfd_poll check for premature notification on child thread exec";
• ksft_print_msg("Parent: pid: %d\n", getpid());
• pid = pidfd_clone(CLONE_PIDFD, &pidfd, child_poll_exec_test);

If pidfd_clone() fails here, I think things will go haywire below.

• ksft_print_msg("Parent: Waiting for Child (%d) to complete.\n", pid);
• if (use_waitpid) {

• ret = waitpid(pid, &status, 0);
  

• if (ret == -1)
  

• 	ksft_print_msg("Parent: error\n");
  

• if (ret == pid)
  

• 	ksft_print_msg("Parent: Child process waited for.\n");
  

• } else {

• poll_pidfd(test_name, pidfd);
  

• }
• time_t prog_time = time(NULL) - prog_start;
• ksft_print_msg("Time waited for child: %lu\n", prog_time);
• close(pidfd);
• if (prog_time < CHILD_THREAD_MIN_WAIT || prog_time > CHILD_THREAD_MIN_WAIT + 2)

• ksft_exit_fail_msg("%s test: Failed\n", test_name);
  

• else

• ksft_test_result_pass("%s test: Passed\n", test_name);
  

+}

+void *test_pidfd_poll_leader_exit_thread(void *priv) +{

• char waittime[256];
• ksft_print_msg("Child Thread: starting. pid %d tid %d ; and sleeping\n",

• 	getpid(), syscall(SYS_gettid));
  

• sleep(CHILD_THREAD_MIN_WAIT);
• ksft_print_msg("Child Thread: DONE. pid %d tid %d\n", getpid(), syscall(SYS_gettid));
• return NULL;

+}

+static time_t *child_exit_secs; +static int child_poll_leader_exit_test(void *args) +{

• pthread_t t1, t2;
• ksft_print_msg("Child: starting. pid %d tid %d\n", getpid(), syscall(SYS_gettid));
• pthread_create(&t1, NULL, test_pidfd_poll_leader_exit_thread, NULL);
• pthread_create(&t2, NULL, test_pidfd_poll_leader_exit_thread, NULL);
• /*

• * glibc exit calls exit_group syscall, so explicity call exit only
  

• * so that only the group leader exits, leaving the threads alone.
  

• */
  

• *child_exit_secs = time(NULL);
• syscall(SYS_exit, 0);

+}

+int test_pidfd_poll_leader_exit(int use_waitpid) +{

• int pid, pidfd = 0;
• int status, ret;
• time_t prog_start = time(NULL);
• const char *test_name = "pidfd_poll check for premature notification on non-empty"

• 		"group leader exit";
  

• child_exit_secs = mmap(NULL, sizeof *child_exit_secs, PROT_READ | PROT_WRITE,

• 	MAP_SHARED | MAP_ANONYMOUS, -1, 0);
  

• ksft_print_msg("Parent: pid: %d\n", getpid());
• pid = pidfd_clone(CLONE_PIDFD, &pidfd, child_poll_leader_exit_test);

Same problem here, I think.

Tycho