[project @ 2001-06-04 16:26:54 by simonmar]

Try doing a major GC before declaring that we're deadlocked, since
there might be finalizers waiting to run that can unblock the system.

Noticed by: Manuel.

diff --git a/ghc/rts/Schedule.c b/ghc/rts/Schedule.c
index 5451cc5..369c8c6 100644 (file)
--- a/ghc/rts/Schedule.c
+++ b/ghc/rts/Schedule.c
@@ -1,5 +1,5 @@
 /* ---------------------------------------------------------------------------
- * $Id: Schedule.c,v 1.95 2001/03/23 16:36:21 simonmar Exp $
+ * $Id: Schedule.c,v 1.96 2001/06/04 16:26:54 simonmar Exp $
  *
  * (c) The GHC Team, 1998-2000
  *
@@ -562,41 +562,42 @@ schedule( void )
      * If no threads are black holed, we have a deadlock situation, so
      * inform all the main threads.
      */
-#ifdef SMP
+#ifndef PAR
     if (blocked_queue_hd == END_TSO_QUEUE
        && run_queue_hd == END_TSO_QUEUE
        && sleeping_queue == END_TSO_QUEUE
-       && (n_free_capabilities == RtsFlags.ParFlags.nNodes))
+#ifdef SMP
+       && (n_free_capabilities == RtsFlags.ParFlags.nNodes)
+#endif
+       )
     {
-       IF_DEBUG(scheduler, sched_belch("deadlocked, checking for black holes..."));
-       detectBlackHoles();
-       if (run_queue_hd == END_TSO_QUEUE) {
-           StgMainThread *m;
-           for (m = main_threads; m != NULL; m = m->link) {
+       IF_DEBUG(scheduler, sched_belch("deadlocked, forcing major GC..."));
+       GarbageCollect(GetRoots,rtsTrue);
+       if (blocked_queue_hd == END_TSO_QUEUE
+           && run_queue_hd == END_TSO_QUEUE
+           && sleeping_queue == END_TSO_QUEUE) {
+           IF_DEBUG(scheduler, sched_belch("still deadlocked, checking for black holes..."));
+           detectBlackHoles();
+           if (run_queue_hd == END_TSO_QUEUE) {
+               StgMainThread *m = main_threads;
+#ifdef SMP
+               for (; m != NULL; m = m->link) {
+                   m->ret = NULL;
+                   m->stat = Deadlock;
+                   pthread_cond_broadcast(&m->wakeup);
+               }
+               main_threads = NULL;
+#else
                m->ret = NULL;
                m->stat = Deadlock;
-               pthread_cond_broadcast(&m->wakeup);
+               main_threads = m->link;
+               return;
+#endif
            }
-           main_threads = NULL;
        }
     }
 #elif defined(PAR)
     /* ToDo: add deadlock detection in GUM (similar to SMP) -- HWL */
-#else /* ! SMP */
-    if (blocked_queue_hd == END_TSO_QUEUE
-       && run_queue_hd == END_TSO_QUEUE
-       && sleeping_queue == END_TSO_QUEUE)
-    {
-       IF_DEBUG(scheduler, sched_belch("deadlocked, checking for black holes..."));
-       detectBlackHoles();
-       if (run_queue_hd == END_TSO_QUEUE) {
-           StgMainThread *m = main_threads;
-           m->ret = NULL;
-           m->stat = Deadlock;
-           main_threads = m->link;
-           return;
-       }
-    }
 #endif
 
 #ifdef SMP