* Task.startTask() uses its current value.
*/
nat rts_n_waiting_tasks = 0;
+
+static Condition *passTarget = NULL;
+static rtsBool passingCapability = rtsFalse;
#endif
/* -----------------------------------------------------------------------------
*/
void grabCapability(Capability** cap)
{
-#ifdef RTS_SUPPORTS_THREADS
- ASSERT(rts_n_free_capabilities > 0);
-#endif
#if !defined(SMP)
+ ASSERT(rts_n_free_capabilities == 1);
rts_n_free_capabilities = 0;
*cap = &MainCapability;
handleSignalsInThisThread();
rts_n_free_capabilities--;
#endif
#ifdef RTS_SUPPORTS_THREADS
- IF_DEBUG(scheduler,
- fprintf(stderr,"worker thread (%p): got capability\n",
- osThreadId()));
+ IF_DEBUG(scheduler, sched_belch("worker: got capability"));
#endif
}
#endif
rts_n_waiting_workers--;
signalCondition(&returning_worker_cond);
+ IF_DEBUG(scheduler, sched_belch("worker: released capability to returning worker"));
} else /*if ( !EMPTY_RUN_QUEUE() )*/ {
#if defined(SMP)
cap->link = free_capabilities;
#endif
/* Signal that a capability is available */
signalCondition(&thread_ready_cond);
+ startSchedulerTaskIfNecessary(); // if there is more work to be done,
+ // we'll need a new thread
+ IF_DEBUG(scheduler, sched_belch("worker: released capability"));
}
#endif
-#ifdef RTS_SUPPORTS_THREADS
- IF_DEBUG(scheduler,
- fprintf(stderr,"worker thread (%p): released capability\n",
- osThreadId()));
-#endif
- return;
+ return;
}
#if defined(RTS_SUPPORTS_THREADS)
void
grabReturnCapability(Mutex* pMutex, Capability** pCap)
{
- IF_DEBUG(scheduler,
- fprintf(stderr,"worker (%p): returning, waiting for lock.\n", osThreadId()));
- IF_DEBUG(scheduler,
- fprintf(stderr,"worker (%p): returning; workers waiting: %d\n",
- osThreadId(), rts_n_waiting_workers));
- if ( noCapabilities() ) {
+ IF_DEBUG(scheduler,
+ sched_belch("worker: returning; workers waiting: %d",
+ rts_n_waiting_workers));
+ if ( noCapabilities() || passingCapability ) {
rts_n_waiting_workers++;
wakeBlockedWorkerThread();
context_switch = 1; // make sure it's our turn soon
yieldToReturningWorker(Mutex* pMutex, Capability** pCap, Condition* pThreadCond)
{
if ( rts_n_waiting_workers > 0 ) {
- IF_DEBUG(scheduler,
- fprintf(stderr,"worker thread (%p): giving up RTS token\n", osThreadId()));
+ IF_DEBUG(scheduler, sched_belch("worker: giving up capability"));
releaseCapability(*pCap);
/* And wait for work */
waitForWorkCapability(pMutex, pCap, pThreadCond);
IF_DEBUG(scheduler,
- fprintf(stderr,"worker thread (%p): got back RTS token (after yieldToReturningWorker)\n",
- osThreadId()));
+ sched_belch("worker: got back capability (after yieldToReturningWorker)"));
}
return;
}
* Post-condition: pMutex is held and *pCap is held by the current thread
*/
-static Condition *passTarget = NULL;
-
void
waitForWorkCapability(Mutex* pMutex, Capability** pCap, Condition* pThreadCond)
{
#ifdef SMP
#error SMP version not implemented
#endif
- IF_DEBUG(scheduler,
- fprintf(stderr,"worker thread (%p): wait for cap (cond: %p)\n",
- osThreadId(),pThreadCond));
- while ( noCapabilities() || (pThreadCond && passTarget != pThreadCond)
- || (!pThreadCond && passTarget)) {
+ while ( noCapabilities() || (passingCapability && passTarget != pThreadCond)) {
+ IF_DEBUG(scheduler,
+ sched_belch("worker: wait for capability (cond: %p)",
+ pThreadCond));
if(pThreadCond)
{
waitCondition(pThreadCond, pMutex);
- IF_DEBUG(scheduler,
- fprintf(stderr,"worker thread (%p): get passed capability\n",
- osThreadId()));
+ IF_DEBUG(scheduler, sched_belch("worker: get passed capability"));
}
else
{
rts_n_waiting_tasks++;
waitCondition(&thread_ready_cond, pMutex);
rts_n_waiting_tasks--;
- IF_DEBUG(scheduler,
- fprintf(stderr,"worker thread (%p): get normal capability\n",
- osThreadId()));
+ IF_DEBUG(scheduler, sched_belch("worker: get normal capability"));
}
}
- passTarget = NULL;
+ passingCapability = rtsFalse;
grabCapability(pCap);
return;
}
rts_n_free_capabilities = 1;
signalCondition(pTargetThreadCond);
passTarget = pTargetThreadCond;
- IF_DEBUG(scheduler,
- fprintf(stderr,"worker thread (%p): passCapability\n",
- osThreadId()));
+ passingCapability = rtsTrue;
+ IF_DEBUG(scheduler, sched_belch("worker: passCapability"));
+}
+
+/*
+ * Function: passCapabilityToWorker(Mutex*, Capability*)
+ *
+ * Purpose: Let go of the capability and make sure that a
+ * "plain" worker thread (not a bound thread) gets it next.
+ *
+ * Pre-condition: pMutex is held and cap is held by the current thread
+ * Post-condition: pMutex is held; cap will be grabbed by the "target"
+ * thread when pMutex is released.
+ */
+
+void
+passCapabilityToWorker(Mutex* pMutex, Capability* cap)
+{
+#ifdef SMP
+ #error SMP version not implemented
+#endif
+ rts_n_free_capabilities = 1;
+ signalCondition(&thread_ready_cond);
+ startSchedulerTaskIfNecessary();
+ passTarget = NULL;
+ passingCapability = rtsTrue;
+ IF_DEBUG(scheduler, sched_belch("worker: passCapabilityToWorker"));
}
+
#endif /* RTS_SUPPORTS_THREADS */
#if defined(SMP)
free_capabilities = cap;
rts_n_free_capabilities = n;
returning_capabilities = NULL;
- IF_DEBUG(scheduler,fprintf(stderr,"scheduler: Allocated %d capabilities\n", n_free_capabilities););
+ IF_DEBUG(scheduler,
+ sched_belch("allocated %d capabilities", n_free_capabilities));
}
#endif /* SMP */