remove empty dir

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

diff --git a/ghc/rts/Capability.c b/ghc/rts/Capability.c
index 8c40b63..51a42ef 100644 (file)
--- a/ghc/rts/Capability.c
+++ b/ghc/rts/Capability.c
@@ -44,7 +44,7 @@ STATIC_INLINE rtsBool
 globalWorkToDo (void)
 {
     return blackholes_need_checking
-       || interrupted
+       || sched_state >= SCHED_INTERRUPTING
        ;
 }
 #endif
@@ -67,7 +67,9 @@ anyWorkForMe( Capability *cap, Task *task )
        // other global condition to check, such as threads blocked on
        // blackholes).
        if (emptyRunQueue(cap)) {
-           return !emptySparkPoolCap(cap) || globalWorkToDo();
+           return !emptySparkPoolCap(cap)
+               || !emptyWakeupQueue(cap)
+               || globalWorkToDo();
        } else
            return cap->run_queue_hd->bound == NULL;
     }
@@ -135,6 +137,8 @@ initCapability( Capability *cap, nat i )
     cap->suspended_ccalling_tasks = NULL;
     cap->returning_tasks_hd = NULL;
     cap->returning_tasks_tl = NULL;
+    cap->wakeup_queue_hd    = END_TSO_QUEUE;
+    cap->wakeup_queue_tl    = END_TSO_QUEUE;
 #endif
 
     cap->f.stgGCEnter1     = (F_)__stg_gc_enter_1;
@@ -286,7 +290,7 @@ releaseCapability_ (Capability* cap)
        // is interrupted, we only create a worker task if there
        // are threads that need to be completed.  If the system is
        // shutting down, we never create a new worker.
-       if (!shutting_down_scheduler) {
+       if (sched_state < SCHED_SHUTTING_DOWN || !emptyRunQueue(cap)) {
            IF_DEBUG(scheduler,
                     sched_belch("starting new worker on capability %d", cap->no));
            startWorkerTask(cap, workerStart);
@@ -296,7 +300,8 @@ releaseCapability_ (Capability* cap)
 
     // If we have an unbound thread on the run queue, or if there's
     // anything else to do, give the Capability to a worker thread.
-    if (!emptyRunQueue(cap) || !emptySparkPoolCap(cap) || globalWorkToDo()) {
+    if (!emptyRunQueue(cap) || !emptyWakeupQueue(cap)
+             || !emptySparkPoolCap(cap) || globalWorkToDo()) {
        if (cap->spare_workers) {
            giveCapabilityToTask(cap,cap->spare_workers);
            // The worker Task pops itself from the queue;
@@ -502,6 +507,37 @@ yieldCapability (Capability** pCap, Task *task)
 }
 
 /* ----------------------------------------------------------------------------
+ * Wake up a thread on a Capability.
+ *
+ * This is used when the current Task is running on a Capability and
+ * wishes to wake up a thread on a different Capability.
+ * ------------------------------------------------------------------------- */
+
+void
+wakeupThreadOnCapability (Capability *cap, StgTSO *tso)
+{
+    ASSERT(tso->cap == cap);
+    ASSERT(tso->bound ? tso->bound->cap == cap : 1);
+
+    ACQUIRE_LOCK(&cap->lock);
+    if (cap->running_task == NULL) {
+       // nobody is running this Capability, we can add our thread
+       // directly onto the run queue and start up a Task to run it.
+       appendToRunQueue(cap,tso);
+
+       // start it up
+       cap->running_task = myTask(); // precond for releaseCapability_()
+       releaseCapability_(cap);
+    } else {
+       appendToWakeupQueue(cap,tso);
+       // someone is running on this Capability, so it cannot be
+       // freed without first checking the wakeup queue (see
+       // releaseCapability_).
+    }
+    RELEASE_LOCK(&cap->lock);
+}
+
+/* ----------------------------------------------------------------------------
  * prodCapabilities
  *
  * Used to indicate that the interrupted flag is now set, or some
@@ -575,7 +611,7 @@ shutdownCapability (Capability *cap, Task *task)
 {
     nat i;
 
-    ASSERT(interrupted && shutting_down_scheduler);
+    ASSERT(sched_state == SCHED_SHUTTING_DOWN);
 
     task->cap = cap;