Redesigned how cancellation unblocks a thread from internal cancellation points (sem_wait, pthread_join, pthread_cond_{wait,timedwait}). Cancellation won't eat a signal in any of these functions (*required* by POSIX and Single Unix Spec!).

2000-01-03  Kaz Kylheku  <kaz@ashi.footprints.net>

	Redesigned how cancellation unblocks a thread from internal
	cancellation points (sem_wait, pthread_join,
	pthread_cond_{wait,timedwait}).
	Cancellation won't eat a signal in any of these functions
	(*required* by POSIX and Single Unix Spec!).
	* condvar.c: spontaneous wakeup on pthread_cond_timedwait won't eat a
	simultaneous condition variable signal (not required by POSIX
	or Single Unix Spec, but nice).
	* spinlock.c: __pthread_lock queues back any received restarts
	that don't belong to it instead of assuming ownership of lock
	upon any restart; fastlock can no longer be acquired by two threads
	simultaneously.
	* restart.h: restarts queue even on kernels that don't have
	queued real time signals (2.0, early 2.1), thanks to atomic counter,
	avoiding a rare race condition in pthread_cond_timedwait.

1 files changed, 2 insertions, 33 deletions

diff --git a/linuxthreads/restart.h b/linuxthreads/restart.h
index 749201391d..702d7d15c6 100644
--- a/linuxthreads/restart.h
+++ b/linuxthreads/restart.h
@@ -18,41 +18,10 @@
 
 static inline void restart(pthread_descr th)
 {
-  kill(th->p_pid, __pthread_sig_restart);
+  __pthread_restart(th); /* see pthread.c */ 
 }
 
 static inline void suspend(pthread_descr self)
 {
-  sigset_t mask;
-
-  sigprocmask(SIG_SETMASK, NULL, &mask); /* Get current signal mask */
-  sigdelset(&mask, __pthread_sig_restart); /* Unblock the restart signal */
-  do {
-    self->p_signal = 0;
-    sigsuspend(&mask);                   /* Wait for signal */
-  } while (self->p_signal !=__pthread_sig_restart );
-}
-
-#define suspend_with_cancellation(self) \
-{									      \
-  sigset_t mask;							      \
-  sigjmp_buf jmpbuf;							      \
-									      \
-  sigprocmask(SIG_SETMASK, NULL, &mask); /* Get current signal mask */	      \
-  sigdelset(&mask, __pthread_sig_restart); /* Unblock the restart signal */   \
-  /* No need to save the signal mask, we'll restore it ourselves */	      \
-  if (sigsetjmp(jmpbuf, 0) == 0) {					      \
-    self->p_cancel_jmp = &jmpbuf;					      \
-    if (! (self->p_canceled						      \
-	   && self->p_cancelstate == PTHREAD_CANCEL_ENABLE)) {		      \
-      do {								      \
-	self->p_signal = 0;						      \
-        sigsuspend(&mask);               /* Wait for a signal */	      \
-      } while (self->p_signal != __pthread_sig_restart);		      \
-    }									      \
-    self->p_cancel_jmp = NULL;						      \
-  } else {								      \
-    sigaddset(&mask, __pthread_sig_restart); /* Reblock the restart signal */ \
-    sigprocmask(SIG_SETMASK, &mask, NULL);				      \
-  }									      \
+  __pthread_suspend(self); /* see pthread.c */
 }