[PATCH] [Tsan] Fix the signal_recursive.cc test to pass on systems with high loads

[Dmitry Vyukov]

A more reliable solution would be to remove sigfillset(&act.sa_mask), and change RestartHandler to:

void RestartHandler() {
  sem_post(&g_thread_suspend_ack_sem)
  sem_post(&g_thread_suspend_ack_sem)
}

and then do sem_wait(&g_thread_suspend_ack_sem) both in StartWorld and in SuspendHandler.

But I am not sure that it will not deadlock in some other way. So let's try the sleep first.

http://reviews.llvm.org/D6504