Fix regTableToCapability() if gcc introduces padding

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

diff --git a/rts/Capability.c b/rts/Capability.c
index 9b5d81d..8dddbc5 100644 (file)
--- a/rts/Capability.c
+++ b/rts/Capability.c
@@ -57,15 +57,18 @@ globalWorkToDo (void)
 StgClosure *
 findSpark (Capability *cap)
 {
-  /* use the normal Sparks.h interface (internally modified to enable
-     concurrent stealing) 
-     and immediately turn the spark into a thread when successful
-  */
   Capability *robbed;
   StgClosurePtr spark;
   rtsBool retry;
   nat i = 0;
 
+  if (!emptyRunQueue(cap)) {
+      // If there are other threads, don't try to run any new
+      // sparks: sparks might be speculative, we don't want to take
+      // resources away from the main computation.
+      return 0;
+  }
+
   // first try to get a spark from our own pool.
   // We should be using reclaimSpark(), because it works without
   // needing any atomic instructions:
@@ -205,6 +208,7 @@ initCapability( Capability *cap, nat i )
     cap->sparks_pruned      = 0;
 #endif
 
+    cap->f.stgEagerBlackholeInfo = (W_)&__stg_EAGER_BLACKHOLE_info;
     cap->f.stgGCEnter1     = (F_)__stg_gc_enter_1;
     cap->f.stgGCFun        = (F_)__stg_gc_fun;
 
@@ -725,8 +729,6 @@ shutdownCapability (Capability *cap, Task *task, rtsBool safe)
 {
     nat i;
 
-    ASSERT(sched_state == SCHED_SHUTTING_DOWN);
-
     task->cap = cap;
 
     // Loop indefinitely until all the workers have exited and there
@@ -736,6 +738,8 @@ shutdownCapability (Capability *cap, Task *task, rtsBool safe)
     // isn't safe, for one thing).
 
     for (i = 0; /* i < 50 */; i++) {
+        ASSERT(sched_state == SCHED_SHUTTING_DOWN);
+
        debugTrace(DEBUG_sched, 
                   "shutting down capability %d, attempt %d", cap->no, i);
        ACQUIRE_LOCK(&cap->lock);