tests/kqueue_close.c

   1 #include <unistd.h>
   2 #include <pthread.h>
   3 #include <errno.h>
   4
   5 #include <sys/event.h>
   6
   7 #include <darwintest.h>
   8
   9 /*
  10  * <rdar://problem/30231213> close() of kqueue FD races with kqueue_scan park
  11  *
  12  * When close concurrent with poll goes wrong, the close hangs
  13  * and the kevent never gets any more events.
  14  */
  15
  16 /* Both events should fire at about the same time */
  17 static uint32_t timeout_ms = 10;
  18
  19 static void *
  20 poll_kqueue(void *arg)
  21 {
  22         int fd = (int)arg;
  23
  24         struct kevent kev = {
  25                 .filter = EVFILT_TIMER,
  26                 .flags  = EV_ADD,
  27                 .data   = timeout_ms,
  28         };
  29
  30         int rv = kevent(fd, &kev, 1, NULL, 0, NULL);
  31
  32         if (rv == -1 && errno == EBADF) {
  33                 /* The close may race with this thread spawning */
  34                 T_LOG("kqueue already closed?");
  35                 return NULL;
  36         } else {
  37                 T_QUIET; T_ASSERT_POSIX_SUCCESS(rv, "kevent");
  38         }
  39
  40         while ((rv = kevent(fd, NULL, 0, &kev, 1, NULL)) == 1) {
  41                 T_LOG("poll\n");
  42         }
  43
  44         if (rv != -1 || errno != EBADF) {
  45                 T_ASSERT_POSIX_SUCCESS(rv, "fd should be closed");
  46         }
  47
  48         return NULL;
  49 }
  50
  51 static void
  52 run_test()
  53 {
  54         int fd = kqueue();
  55         T_QUIET; T_ASSERT_POSIX_SUCCESS(fd, "kqueue");
  56
  57         pthread_t thread;
  58         int rv = pthread_create(&thread, NULL, poll_kqueue,
  59                                 (void *)(uintptr_t)fd);
  60         T_QUIET; T_ASSERT_POSIX_SUCCESS(rv, "pthread_create");
  61
  62         usleep(timeout_ms * 1000);
  63
  64         rv = close(fd);
  65         T_ASSERT_POSIX_SUCCESS(rv, "close");
  66
  67         rv = pthread_join(thread, NULL);
  68         T_QUIET; T_ASSERT_POSIX_SUCCESS(rv, "pthread_join");
  69 }
  70
  71 T_DECL(kqueue_close_race, "Races kqueue close with kqueue process",
  72        T_META_LTEPHASE(LTE_POSTINIT), T_META_TIMEOUT(5))
  73 {
  74         for (uint32_t i = 1 ; i < 100 ; i++) {
  75                 run_test();
  76         }
  77 }