[project @ 2004-09-16 01:39:24 by mthomas]

[ghc-hetmet.git] / ghc / rts / Capability.c

diff --git a/ghc/rts/Capability.c b/ghc/rts/Capability.c
index e34f47a..3ea96fe 100644 (file)
--- a/ghc/rts/Capability.c
+++ b/ghc/rts/Capability.c
@@ -28,9 +28,10 @@
 Capability MainCapability;     /* for non-SMP, we have one global capability */
 #endif
 
+#if defined(RTS_SUPPORTS_THREADS)
+
 nat rts_n_free_capabilities;
 
-#if defined(RTS_SUPPORTS_THREADS)
 /* returning_worker_cond: when a worker thread returns from executing an
  * external call, it needs to wait for an RTS Capability before passing
  * on the result of the call to the Haskell thread that made it.
@@ -107,15 +108,15 @@ static void initCapabilities_(nat n);
 void
 initCapabilities( void )
 {
-#if defined(RTS_SUPPORTS_THREADS)
-  initCondition(&returning_worker_cond);
-  initCondition(&thread_ready_cond);
-#endif
-
 #if defined(SMP)
   initCapabilities_(RtsFlags.ParFlags.nNodes);
 #else
   initCapability(&MainCapability);
+#endif
+
+#if defined(RTS_SUPPORTS_THREADS)
+  initCondition(&returning_worker_cond);
+  initCondition(&thread_ready_cond);
   rts_n_free_capabilities = 1;
 #endif
 
@@ -136,12 +137,17 @@ static Capability *returning_capabilities;
    threaded RTS, clients must use waitFor*Capability()).
    ------------------------------------------------------------------------- */
 
+#if defined(RTS_SUPPORTS_THREADS)
+static
+#endif
 void
 grabCapability( Capability** cap )
 {
 #if !defined(SMP)
+#if defined(RTS_SUPPORTS_THREADS)
   ASSERT(rts_n_free_capabilities == 1);
   rts_n_free_capabilities = 0;
+#endif
   *cap = &MainCapability;
   handleSignalsInThisThread();
 #else
@@ -149,7 +155,9 @@ grabCapability( Capability** cap )
   free_capabilities = (*cap)->link;
   rts_n_free_capabilities--;
 #endif
+#if defined(RTS_SUPPORTS_THREADS)
   IF_DEBUG(scheduler, sched_belch("worker: got capability"));
+#endif
 }
 
 /* ----------------------------------------------------------------------------
@@ -203,7 +211,9 @@ releaseCapability( Capability* cap UNUSED_IF_NOT_SMP )
        rts_n_free_capabilities = 1;
 #endif
        // Signal that a capability is available
-       signalCondition(&thread_ready_cond);
+       if (rts_n_waiting_tasks > 0) {
+           signalCondition(&thread_ready_cond);
+       }
        startSchedulerTaskIfNecessary();
        IF_DEBUG(scheduler, sched_belch("worker: released capability"));
     }