+ /* adjust time based on time-stamp */
+ if (event->time > CurrentTime[CurrentProc] &&
+ event->evttype != ContinueThread)
+ CurrentTime[CurrentProc] = event->time;
+
+ /* Deal with the idle PEs (may issue FindWork or MoveSpark events) */
+ if (!RtsFlags.GranFlags.Light)
+ handleIdlePEs();
+
+ IF_DEBUG(gran, fprintf(stderr, "GRAN: switch by event-type\n"));
+
+ /* main event dispatcher in GranSim */
+ switch (event->evttype) {
+ /* Should just be continuing execution */
+ case ContinueThread:
+ IF_DEBUG(gran, fprintf(stderr, "GRAN: doing ContinueThread\n"));
+ /* ToDo: check assertion
+ ASSERT(run_queue_hd != (StgTSO*)NULL &&
+ run_queue_hd != END_TSO_QUEUE);
+ */
+ /* Ignore ContinueThreads for fetching threads (if synchr comm) */
+ if (!RtsFlags.GranFlags.DoAsyncFetch &&
+ procStatus[CurrentProc]==Fetching) {
+ belch("ghuH: Spurious ContinueThread while Fetching ignored; TSO %d (%p) [PE %d]",
+ CurrentTSO->id, CurrentTSO, CurrentProc);
+ goto next_thread;
+ }
+ /* Ignore ContinueThreads for completed threads */
+ if (CurrentTSO->what_next == ThreadComplete) {
+ belch("ghuH: found a ContinueThread event for completed thread %d (%p) [PE %d] (ignoring ContinueThread)",
+ CurrentTSO->id, CurrentTSO, CurrentProc);
+ goto next_thread;
+ }
+ /* Ignore ContinueThreads for threads that are being migrated */
+ if (PROCS(CurrentTSO)==Nowhere) {
+ belch("ghuH: trying to run the migrating TSO %d (%p) [PE %d] (ignoring ContinueThread)",
+ CurrentTSO->id, CurrentTSO, CurrentProc);
+ goto next_thread;
+ }
+ /* The thread should be at the beginning of the run queue */
+ if (CurrentTSO!=run_queue_hds[CurrentProc]) {
+ belch("ghuH: TSO %d (%p) [PE %d] is not at the start of the run_queue when doing a ContinueThread",
+ CurrentTSO->id, CurrentTSO, CurrentProc);
+ break; // run the thread anyway
+ }
+ /*
+ new_event(proc, proc, CurrentTime[proc],
+ FindWork,
+ (StgTSO*)NULL, (StgClosure*)NULL, (rtsSpark*)NULL);
+ goto next_thread;
+ */ /* Catches superfluous CONTINUEs -- should be unnecessary */
+ break; // now actually run the thread; DaH Qu'vam yImuHbej
+
+ case FetchNode:
+ do_the_fetchnode(event);
+ goto next_thread; /* handle next event in event queue */
+
+ case GlobalBlock:
+ do_the_globalblock(event);
+ goto next_thread; /* handle next event in event queue */
+
+ case FetchReply:
+ do_the_fetchreply(event);
+ goto next_thread; /* handle next event in event queue */
+
+ case UnblockThread: /* Move from the blocked queue to the tail of */
+ do_the_unblock(event);
+ goto next_thread; /* handle next event in event queue */
+
+ case ResumeThread: /* Move from the blocked queue to the tail of */
+ /* the runnable queue ( i.e. Qu' SImqa'lu') */
+ event->tso->gran.blocktime +=
+ CurrentTime[CurrentProc] - event->tso->gran.blockedat;
+ do_the_startthread(event);
+ goto next_thread; /* handle next event in event queue */
+
+ case StartThread:
+ do_the_startthread(event);
+ goto next_thread; /* handle next event in event queue */
+
+ case MoveThread:
+ do_the_movethread(event);
+ goto next_thread; /* handle next event in event queue */
+
+ case MoveSpark:
+ do_the_movespark(event);
+ goto next_thread; /* handle next event in event queue */
+
+ case FindWork:
+ do_the_findwork(event);
+ goto next_thread; /* handle next event in event queue */
+
+ default:
+ barf("Illegal event type %u\n", event->evttype);
+ } /* switch */
+
+ /* This point was scheduler_loop in the old RTS */
+
+ IF_DEBUG(gran, belch("GRAN: after main switch"));
+
+ TimeOfLastEvent = CurrentTime[CurrentProc];
+ TimeOfNextEvent = get_time_of_next_event();
+ IgnoreEvents=(TimeOfNextEvent==0); // HWL HACK
+ // CurrentTSO = ThreadQueueHd;
+
+ IF_DEBUG(gran, belch("GRAN: time of next event is: %ld",
+ TimeOfNextEvent));
+
+ if (RtsFlags.GranFlags.Light)
+ GranSimLight_leave_system(event, &ActiveTSO);
+
+ EndOfTimeSlice = CurrentTime[CurrentProc]+RtsFlags.GranFlags.time_slice;
+
+ IF_DEBUG(gran,
+ belch("GRAN: end of time-slice is %#lx", EndOfTimeSlice));
+
+ /* in a GranSim setup the TSO stays on the run queue */
+ t = CurrentTSO;
+ /* Take a thread from the run queue. */
+ t = POP_RUN_QUEUE(); // take_off_run_queue(t);
+
+ IF_DEBUG(gran,
+ fprintf(stderr, "GRAN: About to run current thread, which is\n");
+ G_TSO(t,5));
+
+ context_switch = 0; // turned on via GranYield, checking events and time slice
+
+ IF_DEBUG(gran,
+ DumpGranEvent(GR_SCHEDULE, t));
+
+ procStatus[CurrentProc] = Busy;
+
+#elif defined(PAR)
+ if (PendingFetches != END_BF_QUEUE) {
+ processFetches();
+ }
+
+ /* ToDo: phps merge with spark activation above */
+ /* check whether we have local work and send requests if we have none */
+ if (EMPTY_RUN_QUEUE()) { /* no runnable threads */
+ /* :-[ no local threads => look out for local sparks */
+ /* the spark pool for the current PE */
+ pool = &(MainRegTable.rSparks); // generalise to cap = &MainRegTable
+ if (advisory_thread_count < RtsFlags.ParFlags.maxThreads &&
+ pool->hd < pool->tl) {
+ /*
+ * ToDo: add GC code check that we really have enough heap afterwards!!
+ * Old comment:
+ * If we're here (no runnable threads) and we have pending
+ * sparks, we must have a space problem. Get enough space
+ * to turn one of those pending sparks into a
+ * thread...
+ */
+
+ spark = findSpark(rtsFalse); /* get a spark */
+ if (spark != (rtsSpark) NULL) {
+ tso = activateSpark(spark); /* turn the spark into a thread */
+ IF_PAR_DEBUG(schedule,
+ belch("==== schedule: Created TSO %d (%p); %d threads active",
+ tso->id, tso, advisory_thread_count));
+
+ if (tso==END_TSO_QUEUE) { /* failed to activate spark->back to loop */
+ belch("==^^ failed to activate spark");
+ goto next_thread;
+ } /* otherwise fall through & pick-up new tso */
+ } else {
+ IF_PAR_DEBUG(verbose,
+ belch("==^^ no local sparks (spark pool contains only NFs: %d)",
+ spark_queue_len(pool)));
+ goto next_thread;
+ }
+ }
+
+ /* If we still have no work we need to send a FISH to get a spark
+ from another PE
+ */
+ if (EMPTY_RUN_QUEUE()) {
+ /* =8-[ no local sparks => look for work on other PEs */
+ /*
+ * We really have absolutely no work. Send out a fish
+ * (there may be some out there already), and wait for
+ * something to arrive. We clearly can't run any threads
+ * until a SCHEDULE or RESUME arrives, and so that's what
+ * we're hoping to see. (Of course, we still have to
+ * respond to other types of messages.)
+ */
+ TIME now = msTime() /*CURRENT_TIME*/;
+ IF_PAR_DEBUG(verbose,
+ belch("-- now=%ld", now));
+ IF_PAR_DEBUG(verbose,
+ if (outstandingFishes < RtsFlags.ParFlags.maxFishes &&
+ (last_fish_arrived_at!=0 &&
+ last_fish_arrived_at+RtsFlags.ParFlags.fishDelay > now)) {
+ belch("--$$ delaying FISH until %ld (last fish %ld, delay %ld, now %ld)",
+ last_fish_arrived_at+RtsFlags.ParFlags.fishDelay,
+ last_fish_arrived_at,
+ RtsFlags.ParFlags.fishDelay, now);
+ });
+
+ if (outstandingFishes < RtsFlags.ParFlags.maxFishes &&
+ (last_fish_arrived_at==0 ||
+ (last_fish_arrived_at+RtsFlags.ParFlags.fishDelay <= now))) {
+ /* outstandingFishes is set in sendFish, processFish;
+ avoid flooding system with fishes via delay */
+ pe = choosePE();
+ sendFish(pe, mytid, NEW_FISH_AGE, NEW_FISH_HISTORY,
+ NEW_FISH_HUNGER);
+
+ // Global statistics: count no. of fishes
+ if (RtsFlags.ParFlags.ParStats.Global &&
+ RtsFlags.GcFlags.giveStats > NO_GC_STATS) {
+ globalParStats.tot_fish_mess++;
+ }
+ }
+
+ receivedFinish = processMessages();
+ goto next_thread;
+ }
+ } else if (PacketsWaiting()) { /* Look for incoming messages */
+ receivedFinish = processMessages();
+ }
+
+ /* Now we are sure that we have some work available */
+ ASSERT(run_queue_hd != END_TSO_QUEUE);
+
+ /* Take a thread from the run queue, if we have work */
+ t = POP_RUN_QUEUE(); // take_off_run_queue(END_TSO_QUEUE);
+ IF_DEBUG(sanity,checkTSO(t));
+
+ /* ToDo: write something to the log-file
+ if (RTSflags.ParFlags.granSimStats && !sameThread)
+ DumpGranEvent(GR_SCHEDULE, RunnableThreadsHd);
+
+ CurrentTSO = t;
+ */
+ /* the spark pool for the current PE */
+ pool = &(MainRegTable.rSparks); // generalise to cap = &MainRegTable
+
+ IF_DEBUG(scheduler,
+ belch("--=^ %d threads, %d sparks on [%#x]",
+ run_queue_len(), spark_queue_len(pool), CURRENT_PROC));
+
+#if 1
+ if (0 && RtsFlags.ParFlags.ParStats.Full &&
+ t && LastTSO && t->id != LastTSO->id &&
+ LastTSO->why_blocked == NotBlocked &&
+ LastTSO->what_next != ThreadComplete) {
+ // if previously scheduled TSO not blocked we have to record the context switch
+ DumpVeryRawGranEvent(TimeOfLastYield, CURRENT_PROC, CURRENT_PROC,
+ GR_DESCHEDULE, LastTSO, (StgClosure *)NULL, 0, 0);
+ }
+
+ if (RtsFlags.ParFlags.ParStats.Full &&
+ (emitSchedule /* forced emit */ ||
+ (t && LastTSO && t->id != LastTSO->id))) {
+ /*
+ we are running a different TSO, so write a schedule event to log file
+ NB: If we use fair scheduling we also have to write a deschedule
+ event for LastTSO; with unfair scheduling we know that the
+ previous tso has blocked whenever we switch to another tso, so
+ we don't need it in GUM for now
+ */
+ DumpRawGranEvent(CURRENT_PROC, CURRENT_PROC,
+ GR_SCHEDULE, t, (StgClosure *)NULL, 0, 0);
+ emitSchedule = rtsFalse;
+ }
+
+#endif
+#else /* !GRAN && !PAR */
+
+ /* grab a thread from the run queue
+ */
+ ASSERT(run_queue_hd != END_TSO_QUEUE);
+ t = POP_RUN_QUEUE();
+ IF_DEBUG(sanity,checkTSO(t));
+
+#endif
+
+ /* grab a capability
+ */
+#ifdef SMP
+ cap = free_capabilities;
+ free_capabilities = cap->link;
+ n_free_capabilities--;
+#else
+ cap = &MainRegTable;
+#endif
+
+ cap->rCurrentTSO = t;
+
+ /* context switches are now initiated by the timer signal, unless
+ * the user specified "context switch as often as possible", with
+ * +RTS -C0
+ */
+ if (RtsFlags.ConcFlags.ctxtSwitchTicks == 0
+ && (run_queue_hd != END_TSO_QUEUE
+ || blocked_queue_hd != END_TSO_QUEUE
+ || sleeping_queue != END_TSO_QUEUE))
+ context_switch = 1;
+ else
+ context_switch = 0;
+
+ RELEASE_LOCK(&sched_mutex);
+
+ IF_DEBUG(scheduler, sched_belch("-->> Running TSO %ld (%p) %s ...",
+ t->id, t, whatNext_strs[t->what_next]));
+
+ /* +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ */
+ /* Run the current thread
+ */
+ switch (cap->rCurrentTSO->what_next) {
+ case ThreadKilled:
+ case ThreadComplete:
+ /* Thread already finished, return to scheduler. */
+ ret = ThreadFinished;
+ break;
+ case ThreadEnterGHC:
+ ret = StgRun((StgFunPtr) stg_enterStackTop, cap);
+ break;
+ case ThreadRunGHC:
+ ret = StgRun((StgFunPtr) stg_returnToStackTop, cap);
+ break;
+ case ThreadEnterInterp:
+ ret = interpretBCO(cap);
+ break;
+ default:
+ barf("schedule: invalid what_next field");
+ }
+ /* +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ */
+
+ /* Costs for the scheduler are assigned to CCS_SYSTEM */
+#ifdef PROFILING
+ CCCS = CCS_SYSTEM;
+#endif
+
+ ACQUIRE_LOCK(&sched_mutex);
+
+#ifdef SMP
+ IF_DEBUG(scheduler,fprintf(stderr,"scheduler (task %ld): ", pthread_self()););
+#elif !defined(GRAN) && !defined(PAR)
+ IF_DEBUG(scheduler,fprintf(stderr,"scheduler: "););
+#endif
+ t = cap->rCurrentTSO;
+
+#if defined(PAR)
+ /* HACK 675: if the last thread didn't yield, make sure to print a
+ SCHEDULE event to the log file when StgRunning the next thread, even
+ if it is the same one as before */
+ LastTSO = t;
+ TimeOfLastYield = CURRENT_TIME;
+#endif
+
+ switch (ret) {
+ case HeapOverflow:
+#if defined(GRAN)
+ IF_DEBUG(gran,
+ DumpGranEvent(GR_DESCHEDULE, t));
+ globalGranStats.tot_heapover++;
+#elif defined(PAR)
+ // IF_DEBUG(par,
+ //DumpGranEvent(GR_DESCHEDULE, t);
+ globalParStats.tot_heapover++;
+#endif
+ /* make all the running tasks block on a condition variable,
+ * maybe set context_switch and wait till they all pile in,
+ * then have them wait on a GC condition variable.
+ */
+ IF_DEBUG(scheduler,belch("--<< thread %ld (%p; %s) stopped: HeapOverflow",
+ t->id, t, whatNext_strs[t->what_next]));
+ threadPaused(t);
+#if defined(GRAN)
+ ASSERT(!is_on_queue(t,CurrentProc));
+#elif defined(PAR)
+ /* Currently we emit a DESCHEDULE event before GC in GUM.
+ ToDo: either add separate event to distinguish SYSTEM time from rest
+ or just nuke this DESCHEDULE (and the following SCHEDULE) */
+ if (0 && RtsFlags.ParFlags.ParStats.Full) {
+ DumpRawGranEvent(CURRENT_PROC, CURRENT_PROC,
+ GR_DESCHEDULE, t, (StgClosure *)NULL, 0, 0);
+ emitSchedule = rtsTrue;
+ }
+#endif
+
+ ready_to_gc = rtsTrue;
+ context_switch = 1; /* stop other threads ASAP */
+ PUSH_ON_RUN_QUEUE(t);
+ /* actual GC is done at the end of the while loop */
+ break;
+
+ case StackOverflow:
+#if defined(GRAN)
+ IF_DEBUG(gran,
+ DumpGranEvent(GR_DESCHEDULE, t));
+ globalGranStats.tot_stackover++;
+#elif defined(PAR)
+ // IF_DEBUG(par,
+ // DumpGranEvent(GR_DESCHEDULE, t);
+ globalParStats.tot_stackover++;
+#endif
+ IF_DEBUG(scheduler,belch("--<< thread %ld (%p; %s) stopped, StackOverflow",
+ t->id, t, whatNext_strs[t->what_next]));
+ /* just adjust the stack for this thread, then pop it back
+ * on the run queue.
+ */
+ threadPaused(t);
+ {
+ StgMainThread *m;
+ /* enlarge the stack */
+ StgTSO *new_t = threadStackOverflow(t);
+
+ /* This TSO has moved, so update any pointers to it from the
+ * main thread stack. It better not be on any other queues...
+ * (it shouldn't be).
+ */
+ for (m = main_threads; m != NULL; m = m->link) {
+ if (m->tso == t) {
+ m->tso = new_t;
+ }
+ }
+ threadPaused(new_t);
+ PUSH_ON_RUN_QUEUE(new_t);
+ }
+ break;
+
+ case ThreadYielding:
+#if defined(GRAN)
+ IF_DEBUG(gran,
+ DumpGranEvent(GR_DESCHEDULE, t));
+ globalGranStats.tot_yields++;
+#elif defined(PAR)
+ // IF_DEBUG(par,
+ // DumpGranEvent(GR_DESCHEDULE, t);
+ globalParStats.tot_yields++;
+#endif
+ /* put the thread back on the run queue. Then, if we're ready to
+ * GC, check whether this is the last task to stop. If so, wake
+ * up the GC thread. getThread will block during a GC until the
+ * GC is finished.
+ */
+ IF_DEBUG(scheduler,
+ if (t->what_next == ThreadEnterInterp) {
+ /* ToDo: or maybe a timer expired when we were in Hugs?
+ * or maybe someone hit ctrl-C
+ */
+ belch("--<< thread %ld (%p; %s) stopped to switch to Hugs",
+ t->id, t, whatNext_strs[t->what_next]);
+ } else {
+ belch("--<< thread %ld (%p; %s) stopped, yielding",
+ t->id, t, whatNext_strs[t->what_next]);
+ }
+ );
+
+ threadPaused(t);
+
+ IF_DEBUG(sanity,
+ //belch("&& Doing sanity check on yielding TSO %ld.", t->id);
+ checkTSO(t));
+ ASSERT(t->link == END_TSO_QUEUE);
+#if defined(GRAN)
+ ASSERT(!is_on_queue(t,CurrentProc));
+
+ IF_DEBUG(sanity,
+ //belch("&& Doing sanity check on all ThreadQueues (and their TSOs).");
+ checkThreadQsSanity(rtsTrue));
+#endif
+#if defined(PAR)
+ if (RtsFlags.ParFlags.doFairScheduling) {
+ /* this does round-robin scheduling; good for concurrency */
+ APPEND_TO_RUN_QUEUE(t);
+ } else {
+ /* this does unfair scheduling; good for parallelism */
+ PUSH_ON_RUN_QUEUE(t);
+ }
+#else
+ /* this does round-robin scheduling; good for concurrency */
+ APPEND_TO_RUN_QUEUE(t);
+#endif
+#if defined(GRAN)
+ /* add a ContinueThread event to actually process the thread */
+ new_event(CurrentProc, CurrentProc, CurrentTime[CurrentProc],
+ ContinueThread,
+ t, (StgClosure*)NULL, (rtsSpark*)NULL);
+ IF_GRAN_DEBUG(bq,
+ belch("GRAN: eventq and runnableq after adding yielded thread to queue again:");
+ G_EVENTQ(0);
+ G_CURR_THREADQ(0));
+#endif /* GRAN */
+ break;
+
+ case ThreadBlocked:
+#if defined(GRAN)
+ IF_DEBUG(scheduler,
+ belch("--<< thread %ld (%p; %s) stopped, blocking on node %p [PE %d] with BQ: ",
+ t->id, t, whatNext_strs[t->what_next], t->block_info.closure, (t->block_info.closure==(StgClosure*)NULL ? 99 : where_is(t->block_info.closure)));
+ if (t->block_info.closure!=(StgClosure*)NULL) print_bq(t->block_info.closure));
+
+ // ??? needed; should emit block before
+ IF_DEBUG(gran,
+ DumpGranEvent(GR_DESCHEDULE, t));
+ prune_eventq(t, (StgClosure *)NULL); // prune ContinueThreads for t
+ /*
+ ngoq Dogh!
+ ASSERT(procStatus[CurrentProc]==Busy ||
+ ((procStatus[CurrentProc]==Fetching) &&
+ (t->block_info.closure!=(StgClosure*)NULL)));
+ if (run_queue_hds[CurrentProc] == END_TSO_QUEUE &&
+ !(!RtsFlags.GranFlags.DoAsyncFetch &&
+ procStatus[CurrentProc]==Fetching))
+ procStatus[CurrentProc] = Idle;
+ */
+#elif defined(PAR)
+ IF_DEBUG(scheduler,
+ belch("--<< thread %ld (%p; %s) stopped, blocking on node %p with BQ: ",
+ t->id, t, whatNext_strs[t->what_next], t->block_info.closure));
+ IF_PAR_DEBUG(bq,
+
+ if (t->block_info.closure!=(StgClosure*)NULL)
+ print_bq(t->block_info.closure));
+
+ /* Send a fetch (if BlockedOnGA) and dump event to log file */
+ blockThread(t);
+
+ /* whatever we schedule next, we must log that schedule */
+ emitSchedule = rtsTrue;
+
+#else /* !GRAN */
+ /* don't need to do anything. Either the thread is blocked on
+ * I/O, in which case we'll have called addToBlockedQueue
+ * previously, or it's blocked on an MVar or Blackhole, in which
+ * case it'll be on the relevant queue already.
+ */
+ IF_DEBUG(scheduler,
+ fprintf(stderr, "--<< thread %d (%p) stopped: ", t->id, t);
+ printThreadBlockage(t);
+ fprintf(stderr, "\n"));
+
+ /* Only for dumping event to log file
+ ToDo: do I need this in GranSim, too?
+ blockThread(t);
+ */
+#endif
+ threadPaused(t);
+ break;
+
+ case ThreadFinished:
+ /* Need to check whether this was a main thread, and if so, signal
+ * the task that started it with the return value. If we have no
+ * more main threads, we probably need to stop all the tasks until
+ * we get a new one.
+ */
+ /* We also end up here if the thread kills itself with an
+ * uncaught exception, see Exception.hc.
+ */
+ IF_DEBUG(scheduler,belch("--++ thread %d (%p) finished", t->id, t));
+#if defined(GRAN)
+ endThread(t, CurrentProc); // clean-up the thread
+#elif defined(PAR)
+ /* For now all are advisory -- HWL */
+ //if(t->priority==AdvisoryPriority) ??
+ advisory_thread_count--;
+
+# ifdef DIST
+ if(t->dist.priority==RevalPriority)
+ FinishReval(t);
+# endif
+
+ if (RtsFlags.ParFlags.ParStats.Full &&
+ !RtsFlags.ParFlags.ParStats.Suppressed)
+ DumpEndEvent(CURRENT_PROC, t, rtsFalse /* not mandatory */);
+#endif
+ break;
+
+ default:
+ barf("schedule: invalid thread return code %d", (int)ret);
+ }
+
+#ifdef SMP
+ cap->link = free_capabilities;
+ free_capabilities = cap;
+ n_free_capabilities++;
+#endif
+
+#ifdef SMP
+ if (ready_to_gc && n_free_capabilities == RtsFlags.ParFlags.nNodes)
+#else
+ if (ready_to_gc)
+#endif
+ {
+ /* everybody back, start the GC.
+ * Could do it in this thread, or signal a condition var
+ * to do it in another thread. Either way, we need to
+ * broadcast on gc_pending_cond afterward.
+ */
+#ifdef SMP
+ IF_DEBUG(scheduler,sched_belch("doing GC"));
+#endif
+ GarbageCollect(GetRoots,rtsFalse);
+ ready_to_gc = rtsFalse;
+#ifdef SMP
+ pthread_cond_broadcast(&gc_pending_cond);
+#endif
+#if defined(GRAN)
+ /* add a ContinueThread event to continue execution of current thread */
+ new_event(CurrentProc, CurrentProc, CurrentTime[CurrentProc],
+ ContinueThread,
+ t, (StgClosure*)NULL, (rtsSpark*)NULL);
+ IF_GRAN_DEBUG(bq,
+ fprintf(stderr, "GRAN: eventq and runnableq after Garbage collection:\n");
+ G_EVENTQ(0);
+ G_CURR_THREADQ(0));
+#endif /* GRAN */
+ }
+#if defined(GRAN)
+ next_thread:
+ IF_GRAN_DEBUG(unused,
+ print_eventq(EventHd));
+
+ event = get_next_event();
+
+#elif defined(PAR)
+ next_thread:
+ /* ToDo: wait for next message to arrive rather than busy wait */
+
+#else /* GRAN */
+ /* not any more
+ next_thread:
+ t = take_off_run_queue(END_TSO_QUEUE);
+ */
+#endif /* GRAN */
+ } /* end of while(1) */
+ IF_PAR_DEBUG(verbose,
+ belch("== Leaving schedule() after having received Finish"));
+}
+
+/* ---------------------------------------------------------------------------
+ * deleteAllThreads(): kill all the live threads.
+ *
+ * This is used when we catch a user interrupt (^C), before performing
+ * any necessary cleanups and running finalizers.
+ * ------------------------------------------------------------------------- */
+
+void deleteAllThreads ( void )
+{
+ StgTSO* t;
+ IF_DEBUG(scheduler,sched_belch("deleting all threads"));
+ for (t = run_queue_hd; t != END_TSO_QUEUE; t = t->link) {
+ deleteThread(t);
+ }
+ for (t = blocked_queue_hd; t != END_TSO_QUEUE; t = t->link) {
+ deleteThread(t);
+ }
+ for (t = sleeping_queue; t != END_TSO_QUEUE; t = t->link) {
+ deleteThread(t);
+ }
+ run_queue_hd = run_queue_tl = END_TSO_QUEUE;
+ blocked_queue_hd = blocked_queue_tl = END_TSO_QUEUE;
+ sleeping_queue = END_TSO_QUEUE;
+}
+
+/* startThread and insertThread are now in GranSim.c -- HWL */
+
+//@node Suspend and Resume, Run queue code, Main scheduling loop, Main scheduling code
+//@subsection Suspend and Resume
+
+/* ---------------------------------------------------------------------------
+ * Suspending & resuming Haskell threads.
+ *
+ * When making a "safe" call to C (aka _ccall_GC), the task gives back
+ * its capability before calling the C function. This allows another
+ * task to pick up the capability and carry on running Haskell
+ * threads. It also means that if the C call blocks, it won't lock
+ * the whole system.
+ *
+ * The Haskell thread making the C call is put to sleep for the
+ * duration of the call, on the susepended_ccalling_threads queue. We
+ * give out a token to the task, which it can use to resume the thread
+ * on return from the C function.
+ * ------------------------------------------------------------------------- */
+
+StgInt
+suspendThread( Capability *cap )
+{
+ nat tok;
+
+ ACQUIRE_LOCK(&sched_mutex);
+
+ IF_DEBUG(scheduler,
+ sched_belch("thread %d did a _ccall_gc", cap->rCurrentTSO->id));
+
+ threadPaused(cap->rCurrentTSO);
+ cap->rCurrentTSO->link = suspended_ccalling_threads;
+ suspended_ccalling_threads = cap->rCurrentTSO;
+
+ /* Use the thread ID as the token; it should be unique */
+ tok = cap->rCurrentTSO->id;
+
+#ifdef SMP
+ cap->link = free_capabilities;
+ free_capabilities = cap;
+ n_free_capabilities++;
+#endif
+
+ RELEASE_LOCK(&sched_mutex);
+ return tok;
+}
+
+Capability *
+resumeThread( StgInt tok )
+{
+ StgTSO *tso, **prev;
+ Capability *cap;
+
+ ACQUIRE_LOCK(&sched_mutex);
+
+ prev = &suspended_ccalling_threads;
+ for (tso = suspended_ccalling_threads;
+ tso != END_TSO_QUEUE;
+ prev = &tso->link, tso = tso->link) {
+ if (tso->id == (StgThreadID)tok) {
+ *prev = tso->link;
+ break;
+ }
+ }
+ if (tso == END_TSO_QUEUE) {
+ barf("resumeThread: thread not found");
+ }
+ tso->link = END_TSO_QUEUE;
+
+#ifdef SMP
+ while (free_capabilities == NULL) {
+ IF_DEBUG(scheduler, sched_belch("waiting to resume"));
+ pthread_cond_wait(&thread_ready_cond, &sched_mutex);
+ IF_DEBUG(scheduler, sched_belch("resuming thread %d", tso->id));
+ }
+ cap = free_capabilities;
+ free_capabilities = cap->link;
+ n_free_capabilities--;
+#else
+ cap = &MainRegTable;
+#endif
+
+ cap->rCurrentTSO = tso;
+
+ RELEASE_LOCK(&sched_mutex);
+ return cap;
+}
+
+
+/* ---------------------------------------------------------------------------
+ * Static functions
+ * ------------------------------------------------------------------------ */
+static void unblockThread(StgTSO *tso);
+
+/* ---------------------------------------------------------------------------
+ * Comparing Thread ids.
+ *
+ * This is used from STG land in the implementation of the
+ * instances of Eq/Ord for ThreadIds.
+ * ------------------------------------------------------------------------ */
+
+int cmp_thread(const StgTSO *tso1, const StgTSO *tso2)
+{
+ StgThreadID id1 = tso1->id;
+ StgThreadID id2 = tso2->id;
+
+ if (id1 < id2) return (-1);
+ if (id1 > id2) return 1;
+ return 0;
+}
+
+/* ---------------------------------------------------------------------------
+ Create a new thread.
+
+ The new thread starts with the given stack size. Before the
+ scheduler can run, however, this thread needs to have a closure
+ (and possibly some arguments) pushed on its stack. See
+ pushClosure() in Schedule.h.
+
+ createGenThread() and createIOThread() (in SchedAPI.h) are
+ convenient packaged versions of this function.
+
+ currently pri (priority) is only used in a GRAN setup -- HWL
+ ------------------------------------------------------------------------ */
+//@cindex createThread
+#if defined(GRAN)
+/* currently pri (priority) is only used in a GRAN setup -- HWL */
+StgTSO *
+createThread(nat stack_size, StgInt pri)
+{
+ return createThread_(stack_size, rtsFalse, pri);
+}
+
+static StgTSO *
+createThread_(nat size, rtsBool have_lock, StgInt pri)
+{
+#else
+StgTSO *
+createThread(nat stack_size)
+{
+ return createThread_(stack_size, rtsFalse);
+}
+
+static StgTSO *
+createThread_(nat size, rtsBool have_lock)
+{
+#endif
+
+ StgTSO *tso;
+ nat stack_size;
+
+ /* First check whether we should create a thread at all */
+#if defined(PAR)
+ /* check that no more than RtsFlags.ParFlags.maxThreads threads are created */
+ if (advisory_thread_count >= RtsFlags.ParFlags.maxThreads) {
+ threadsIgnored++;
+ belch("{createThread}Daq ghuH: refusing to create another thread; no more than %d threads allowed (currently %d)",
+ RtsFlags.ParFlags.maxThreads, advisory_thread_count);
+ return END_TSO_QUEUE;
+ }
+ threadsCreated++;
+#endif
+
+#if defined(GRAN)
+ ASSERT(!RtsFlags.GranFlags.Light || CurrentProc==0);
+#endif
+
+ // ToDo: check whether size = stack_size - TSO_STRUCT_SIZEW
+
+ /* catch ridiculously small stack sizes */
+ if (size < MIN_STACK_WORDS + TSO_STRUCT_SIZEW) {
+ size = MIN_STACK_WORDS + TSO_STRUCT_SIZEW;
+ }
+
+ stack_size = size - TSO_STRUCT_SIZEW;
+
+ tso = (StgTSO *)allocate(size);
+ TICK_ALLOC_TSO(size-TSO_STRUCT_SIZEW, 0);
+
+ SET_HDR(tso, &stg_TSO_info, CCS_SYSTEM);
+#if defined(GRAN)
+ SET_GRAN_HDR(tso, ThisPE);
+#endif
+ tso->what_next = ThreadEnterGHC;
+
+ /* tso->id needs to be unique. For now we use a heavyweight mutex to
+ * protect the increment operation on next_thread_id.
+ * In future, we could use an atomic increment instead.
+ */
+ if (!have_lock) { ACQUIRE_LOCK(&sched_mutex); }
+ tso->id = next_thread_id++;
+ if (!have_lock) { RELEASE_LOCK(&sched_mutex); }
+
+ tso->why_blocked = NotBlocked;
+ tso->blocked_exceptions = NULL;
+
+ tso->stack_size = stack_size;
+ tso->max_stack_size = round_to_mblocks(RtsFlags.GcFlags.maxStkSize)
+ - TSO_STRUCT_SIZEW;
+ tso->sp = (P_)&(tso->stack) + stack_size;
+
+#ifdef PROFILING
+ tso->prof.CCCS = CCS_MAIN;
+#endif
+
+ /* put a stop frame on the stack */
+ tso->sp -= sizeofW(StgStopFrame);
+ SET_HDR((StgClosure*)tso->sp,(StgInfoTable *)&stg_stop_thread_info,CCS_SYSTEM);
+ tso->su = (StgUpdateFrame*)tso->sp;
+
+ // ToDo: check this
+#if defined(GRAN)
+ tso->link = END_TSO_QUEUE;
+ /* uses more flexible routine in GranSim */
+ insertThread(tso, CurrentProc);
+#else
+ /* In a non-GranSim setup the pushing of a TSO onto the runq is separated
+ * from its creation
+ */
+#endif
+
+#if defined(GRAN)
+ if (RtsFlags.GranFlags.GranSimStats.Full)
+ DumpGranEvent(GR_START,tso);
+#elif defined(PAR)
+ if (RtsFlags.ParFlags.ParStats.Full)
+ DumpGranEvent(GR_STARTQ,tso);
+ /* HACk to avoid SCHEDULE
+ LastTSO = tso; */
+#endif
+
+ /* Link the new thread on the global thread list.
+ */
+ tso->global_link = all_threads;
+ all_threads = tso;
+
+#if defined(DIST)
+ tso->dist.priority = MandatoryPriority; //by default that is...
+#endif
+
+#if defined(GRAN)
+ tso->gran.pri = pri;
+# if defined(DEBUG)
+ tso->gran.magic = TSO_MAGIC; // debugging only
+# endif
+ tso->gran.sparkname = 0;
+ tso->gran.startedat = CURRENT_TIME;
+ tso->gran.exported = 0;
+ tso->gran.basicblocks = 0;
+ tso->gran.allocs = 0;
+ tso->gran.exectime = 0;
+ tso->gran.fetchtime = 0;
+ tso->gran.fetchcount = 0;
+ tso->gran.blocktime = 0;
+ tso->gran.blockcount = 0;
+ tso->gran.blockedat = 0;
+ tso->gran.globalsparks = 0;
+ tso->gran.localsparks = 0;
+ if (RtsFlags.GranFlags.Light)
+ tso->gran.clock = Now; /* local clock */
+ else
+ tso->gran.clock = 0;
+
+ IF_DEBUG(gran,printTSO(tso));
+#elif defined(PAR)
+# if defined(DEBUG)
+ tso->par.magic = TSO_MAGIC; // debugging only
+# endif
+ tso->par.sparkname = 0;
+ tso->par.startedat = CURRENT_TIME;
+ tso->par.exported = 0;
+ tso->par.basicblocks = 0;
+ tso->par.allocs = 0;
+ tso->par.exectime = 0;
+ tso->par.fetchtime = 0;
+ tso->par.fetchcount = 0;
+ tso->par.blocktime = 0;
+ tso->par.blockcount = 0;
+ tso->par.blockedat = 0;
+ tso->par.globalsparks = 0;
+ tso->par.localsparks = 0;
+#endif
+
+#if defined(GRAN)
+ globalGranStats.tot_threads_created++;
+ globalGranStats.threads_created_on_PE[CurrentProc]++;
+ globalGranStats.tot_sq_len += spark_queue_len(CurrentProc);
+ globalGranStats.tot_sq_probes++;
+#elif defined(PAR)
+ // collect parallel global statistics (currently done together with GC stats)
+ if (RtsFlags.ParFlags.ParStats.Global &&
+ RtsFlags.GcFlags.giveStats > NO_GC_STATS) {
+ //fprintf(stderr, "Creating thread %d @ %11.2f\n", tso->id, usertime());
+ globalParStats.tot_threads_created++;
+ }
+#endif
+
+#if defined(GRAN)
+ IF_GRAN_DEBUG(pri,
+ belch("==__ schedule: Created TSO %d (%p);",
+ CurrentProc, tso, tso->id));
+#elif defined(PAR)
+ IF_PAR_DEBUG(verbose,
+ belch("==__ schedule: Created TSO %d (%p); %d threads active",
+ tso->id, tso, advisory_thread_count));
+#else
+ IF_DEBUG(scheduler,sched_belch("created thread %ld, stack size = %lx words",
+ tso->id, tso->stack_size));
+#endif
+ return tso;
+}
+
+#if defined(PAR)
+/* RFP:
+ all parallel thread creation calls should fall through the following routine.
+*/
+StgTSO *
+createSparkThread(rtsSpark spark)
+{ StgTSO *tso;
+ ASSERT(spark != (rtsSpark)NULL);
+ if (advisory_thread_count >= RtsFlags.ParFlags.maxThreads)
+ { threadsIgnored++;
+ barf("{createSparkThread}Daq ghuH: refusing to create another thread; no more than %d threads allowed (currently %d)",
+ RtsFlags.ParFlags.maxThreads, advisory_thread_count);
+ return END_TSO_QUEUE;
+ }
+ else
+ { threadsCreated++;
+ tso = createThread_(RtsFlags.GcFlags.initialStkSize, rtsTrue);
+ if (tso==END_TSO_QUEUE)
+ barf("createSparkThread: Cannot create TSO");
+#if defined(DIST)
+ tso->priority = AdvisoryPriority;
+#endif
+ pushClosure(tso,spark);
+ PUSH_ON_RUN_QUEUE(tso);
+ advisory_thread_count++;
+ }
+ return tso;
+}
+#endif
+
+/*
+ Turn a spark into a thread.
+ ToDo: fix for SMP (needs to acquire SCHED_MUTEX!)
+*/
+#if defined(PAR)
+//@cindex activateSpark
+StgTSO *
+activateSpark (rtsSpark spark)
+{
+ StgTSO *tso;
+
+ tso = createSparkThread(spark);
+ if (RtsFlags.ParFlags.ParStats.Full) {
+ //ASSERT(run_queue_hd == END_TSO_QUEUE); // I think ...
+ IF_PAR_DEBUG(verbose,
+ belch("==^^ activateSpark: turning spark of closure %p (%s) into a thread",
+ (StgClosure *)spark, info_type((StgClosure *)spark)));
+ }
+ // ToDo: fwd info on local/global spark to thread -- HWL
+ // tso->gran.exported = spark->exported;
+ // tso->gran.locked = !spark->global;
+ // tso->gran.sparkname = spark->name;
+
+ return tso;
+}
+#endif
+
+/* ---------------------------------------------------------------------------
+ * scheduleThread()
+ *
+ * scheduleThread puts a thread on the head of the runnable queue.
+ * This will usually be done immediately after a thread is created.
+ * The caller of scheduleThread must create the thread using e.g.
+ * createThread and push an appropriate closure
+ * on this thread's stack before the scheduler is invoked.
+ * ------------------------------------------------------------------------ */
+
+void
+scheduleThread(StgTSO *tso)
+{
+ if (tso==END_TSO_QUEUE){
+ schedule();
+ return;
+ }
+
+ ACQUIRE_LOCK(&sched_mutex);
+
+ /* Put the new thread on the head of the runnable queue. The caller
+ * better push an appropriate closure on this thread's stack
+ * beforehand. In the SMP case, the thread may start running as
+ * soon as we release the scheduler lock below.
+ */
+ PUSH_ON_RUN_QUEUE(tso);
+ THREAD_RUNNABLE();
+
+#if 0
+ IF_DEBUG(scheduler,printTSO(tso));
+#endif
+ RELEASE_LOCK(&sched_mutex);
+}
+
+/* ---------------------------------------------------------------------------
+ * startTasks()
+ *
+ * Start up Posix threads to run each of the scheduler tasks.
+ * I believe the task ids are not needed in the system as defined.
+ * KH @ 25/10/99
+ * ------------------------------------------------------------------------ */
+
+#if defined(PAR) || defined(SMP)
+void
+taskStart(void) /* ( void *arg STG_UNUSED) */
+{
+ scheduleThread(END_TSO_QUEUE);
+}
+#endif
+
+/* ---------------------------------------------------------------------------
+ * initScheduler()
+ *
+ * Initialise the scheduler. This resets all the queues - if the
+ * queues contained any threads, they'll be garbage collected at the
+ * next pass.
+ *
+ * This now calls startTasks(), so should only be called once! KH @ 25/10/99
+ * ------------------------------------------------------------------------ */
+
+#ifdef SMP
+static void
+term_handler(int sig STG_UNUSED)
+{
+ stat_workerStop();
+ ACQUIRE_LOCK(&term_mutex);
+ await_death--;
+ RELEASE_LOCK(&term_mutex);
+ pthread_exit(NULL);
+}
+#endif
+
+//@cindex initScheduler
+void
+initScheduler(void)
+{
+#if defined(GRAN)
+ nat i;
+
+ for (i=0; i<=MAX_PROC; i++) {
+ run_queue_hds[i] = END_TSO_QUEUE;
+ run_queue_tls[i] = END_TSO_QUEUE;
+ blocked_queue_hds[i] = END_TSO_QUEUE;
+ blocked_queue_tls[i] = END_TSO_QUEUE;
+ ccalling_threadss[i] = END_TSO_QUEUE;
+ sleeping_queue = END_TSO_QUEUE;
+ }
+#else
+ run_queue_hd = END_TSO_QUEUE;
+ run_queue_tl = END_TSO_QUEUE;
+ blocked_queue_hd = END_TSO_QUEUE;
+ blocked_queue_tl = END_TSO_QUEUE;
+ sleeping_queue = END_TSO_QUEUE;
+#endif
+
+ suspended_ccalling_threads = END_TSO_QUEUE;
+
+ main_threads = NULL;
+ all_threads = END_TSO_QUEUE;
+
+ context_switch = 0;
+ interrupted = 0;
+
+ RtsFlags.ConcFlags.ctxtSwitchTicks =
+ RtsFlags.ConcFlags.ctxtSwitchTime / TICK_MILLISECS;
+
+ /* Install the SIGHUP handler */
+#ifdef SMP
+ {
+ struct sigaction action,oact;
+
+ action.sa_handler = term_handler;
+ sigemptyset(&action.sa_mask);
+ action.sa_flags = 0;
+ if (sigaction(SIGTERM, &action, &oact) != 0) {
+ barf("can't install TERM handler");
+ }
+ }
+#endif
+
+#ifdef SMP
+ /* Allocate N Capabilities */
+ {
+ nat i;
+ Capability *cap, *prev;
+ cap = NULL;
+ prev = NULL;
+ for (i = 0; i < RtsFlags.ParFlags.nNodes; i++) {
+ cap = stgMallocBytes(sizeof(Capability), "initScheduler:capabilities");
+ cap->link = prev;
+ prev = cap;
+ }
+ free_capabilities = cap;
+ n_free_capabilities = RtsFlags.ParFlags.nNodes;
+ }
+ IF_DEBUG(scheduler,fprintf(stderr,"scheduler: Allocated %d capabilities\n",
+ n_free_capabilities););
+#endif
+
+#if defined(SMP) || defined(PAR)
+ initSparkPools();
+#endif
+}
+
+#ifdef SMP
+void
+startTasks( void )
+{
+ nat i;
+ int r;
+ pthread_t tid;
+
+ /* make some space for saving all the thread ids */
+ task_ids = stgMallocBytes(RtsFlags.ParFlags.nNodes * sizeof(task_info),
+ "initScheduler:task_ids");
+
+ /* and create all the threads */
+ for (i = 0; i < RtsFlags.ParFlags.nNodes; i++) {
+ r = pthread_create(&tid,NULL,taskStart,NULL);
+ if (r != 0) {
+ barf("startTasks: Can't create new Posix thread");
+ }
+ task_ids[i].id = tid;
+ task_ids[i].mut_time = 0.0;
+ task_ids[i].mut_etime = 0.0;
+ task_ids[i].gc_time = 0.0;
+ task_ids[i].gc_etime = 0.0;
+ task_ids[i].elapsedtimestart = elapsedtime();
+ IF_DEBUG(scheduler,fprintf(stderr,"scheduler: Started task: %ld\n",tid););
+ }
+}
+#endif
+
+void
+exitScheduler( void )
+{
+#ifdef SMP
+ nat i;
+
+ /* Don't want to use pthread_cancel, since we'd have to install
+ * these silly exception handlers (pthread_cleanup_{push,pop}) around
+ * all our locks.
+ */
+#if 0
+ /* Cancel all our tasks */
+ for (i = 0; i < RtsFlags.ParFlags.nNodes; i++) {
+ pthread_cancel(task_ids[i].id);
+ }
+
+ /* Wait for all the tasks to terminate */
+ for (i = 0; i < RtsFlags.ParFlags.nNodes; i++) {
+ IF_DEBUG(scheduler,fprintf(stderr,"scheduler: waiting for task %ld\n",
+ task_ids[i].id));
+ pthread_join(task_ids[i].id, NULL);
+ }
+#endif
+
+ /* Send 'em all a SIGHUP. That should shut 'em up.
+ */
+ await_death = RtsFlags.ParFlags.nNodes;
+ for (i = 0; i < RtsFlags.ParFlags.nNodes; i++) {
+ pthread_kill(task_ids[i].id,SIGTERM);
+ }
+ while (await_death > 0) {
+ sched_yield();
+ }
+#endif
+}
+
+/* -----------------------------------------------------------------------------
+ Managing the per-task allocation areas.
+
+ Each capability comes with an allocation area. These are
+ fixed-length block lists into which allocation can be done.
+
+ ToDo: no support for two-space collection at the moment???
+ -------------------------------------------------------------------------- */
+
+/* -----------------------------------------------------------------------------
+ * waitThread is the external interface for running a new computation
+ * and waiting for the result.
+ *
+ * In the non-SMP case, we create a new main thread, push it on the
+ * main-thread stack, and invoke the scheduler to run it. The
+ * scheduler will return when the top main thread on the stack has
+ * completed or died, and fill in the necessary fields of the
+ * main_thread structure.
+ *
+ * In the SMP case, we create a main thread as before, but we then
+ * create a new condition variable and sleep on it. When our new
+ * main thread has completed, we'll be woken up and the status/result
+ * will be in the main_thread struct.
+ * -------------------------------------------------------------------------- */
+
+int
+howManyThreadsAvail ( void )
+{
+ int i = 0;
+ StgTSO* q;
+ for (q = run_queue_hd; q != END_TSO_QUEUE; q = q->link)
+ i++;
+ for (q = blocked_queue_hd; q != END_TSO_QUEUE; q = q->link)
+ i++;
+ for (q = sleeping_queue; q != END_TSO_QUEUE; q = q->link)
+ i++;
+ return i;
+}
+
+void
+finishAllThreads ( void )
+{
+ do {
+ while (run_queue_hd != END_TSO_QUEUE) {
+ waitThread ( run_queue_hd, NULL );
+ }
+ while (blocked_queue_hd != END_TSO_QUEUE) {
+ waitThread ( blocked_queue_hd, NULL );
+ }
+ while (sleeping_queue != END_TSO_QUEUE) {
+ waitThread ( blocked_queue_hd, NULL );
+ }
+ } while
+ (blocked_queue_hd != END_TSO_QUEUE ||
+ run_queue_hd != END_TSO_QUEUE ||
+ sleeping_queue != END_TSO_QUEUE);
+}
+
+SchedulerStatus
+waitThread(StgTSO *tso, /*out*/StgClosure **ret)
+{
+ StgMainThread *m;
+ SchedulerStatus stat;
+
+ ACQUIRE_LOCK(&sched_mutex);
+
+ m = stgMallocBytes(sizeof(StgMainThread), "waitThread");
+
+ m->tso = tso;
+ m->ret = ret;
+ m->stat = NoStatus;
+#ifdef SMP
+ pthread_cond_init(&m->wakeup, NULL);
+#endif
+
+ m->link = main_threads;
+ main_threads = m;
+
+ IF_DEBUG(scheduler, fprintf(stderr, "== scheduler: new main thread (%d)\n",
+ m->tso->id));
+
+#ifdef SMP
+ do {
+ pthread_cond_wait(&m->wakeup, &sched_mutex);
+ } while (m->stat == NoStatus);
+#elif defined(GRAN)
+ /* GranSim specific init */
+ CurrentTSO = m->tso; // the TSO to run
+ procStatus[MainProc] = Busy; // status of main PE
+ CurrentProc = MainProc; // PE to run it on
+
+ schedule();
+#else
+ schedule();
+ ASSERT(m->stat != NoStatus);
+#endif
+
+ stat = m->stat;
+
+#ifdef SMP
+ pthread_cond_destroy(&m->wakeup);
+#endif
+
+ IF_DEBUG(scheduler, fprintf(stderr, "== scheduler: main thread (%d) finished\n",
+ m->tso->id));
+ free(m);
+
+ RELEASE_LOCK(&sched_mutex);
+
+ return stat;
+}
+
+//@node Run queue code, Garbage Collextion Routines, Suspend and Resume, Main scheduling code
+//@subsection Run queue code
+
+#if 0
+/*
+ NB: In GranSim we have many run queues; run_queue_hd is actually a macro
+ unfolding to run_queue_hds[CurrentProc], thus CurrentProc is an
+ implicit global variable that has to be correct when calling these
+ fcts -- HWL
+*/
+
+/* Put the new thread on the head of the runnable queue.
+ * The caller of createThread better push an appropriate closure
+ * on this thread's stack before the scheduler is invoked.
+ */
+static /* inline */ void
+add_to_run_queue(tso)
+StgTSO* tso;
+{
+ ASSERT(tso!=run_queue_hd && tso!=run_queue_tl);
+ tso->link = run_queue_hd;
+ run_queue_hd = tso;
+ if (run_queue_tl == END_TSO_QUEUE) {
+ run_queue_tl = tso;
+ }
+}
+
+/* Put the new thread at the end of the runnable queue. */
+static /* inline */ void
+push_on_run_queue(tso)
+StgTSO* tso;
+{
+ ASSERT(get_itbl((StgClosure *)tso)->type == TSO);
+ ASSERT(run_queue_hd!=NULL && run_queue_tl!=NULL);
+ ASSERT(tso!=run_queue_hd && tso!=run_queue_tl);
+ if (run_queue_hd == END_TSO_QUEUE) {
+ run_queue_hd = tso;
+ } else {
+ run_queue_tl->link = tso;
+ }
+ run_queue_tl = tso;
+}
+
+/*
+ Should be inlined because it's used very often in schedule. The tso
+ argument is actually only needed in GranSim, where we want to have the
+ possibility to schedule *any* TSO on the run queue, irrespective of the
+ actual ordering. Therefore, if tso is not the nil TSO then we traverse
+ the run queue and dequeue the tso, adjusting the links in the queue.
+*/
+//@cindex take_off_run_queue
+static /* inline */ StgTSO*
+take_off_run_queue(StgTSO *tso) {
+ StgTSO *t, *prev;
+
+ /*
+ qetlaHbogh Qu' ngaSbogh ghomDaQ {tso} yIteq!
+
+ if tso is specified, unlink that tso from the run_queue (doesn't have
+ to be at the beginning of the queue); GranSim only
+ */
+ if (tso!=END_TSO_QUEUE) {
+ /* find tso in queue */
+ for (t=run_queue_hd, prev=END_TSO_QUEUE;
+ t!=END_TSO_QUEUE && t!=tso;
+ prev=t, t=t->link)
+ /* nothing */ ;
+ ASSERT(t==tso);
+ /* now actually dequeue the tso */
+ if (prev!=END_TSO_QUEUE) {
+ ASSERT(run_queue_hd!=t);
+ prev->link = t->link;
+ } else {
+ /* t is at beginning of thread queue */
+ ASSERT(run_queue_hd==t);
+ run_queue_hd = t->link;
+ }
+ /* t is at end of thread queue */
+ if (t->link==END_TSO_QUEUE) {
+ ASSERT(t==run_queue_tl);
+ run_queue_tl = prev;
+ } else {
+ ASSERT(run_queue_tl!=t);
+ }
+ t->link = END_TSO_QUEUE;
+ } else {
+ /* take tso from the beginning of the queue; std concurrent code */
+ t = run_queue_hd;
+ if (t != END_TSO_QUEUE) {
+ run_queue_hd = t->link;
+ t->link = END_TSO_QUEUE;
+ if (run_queue_hd == END_TSO_QUEUE) {
+ run_queue_tl = END_TSO_QUEUE;
+ }
+ }
+ }
+ return t;
+}
+
+#endif /* 0 */
+
+//@node Garbage Collextion Routines, Blocking Queue Routines, Run queue code, Main scheduling code
+//@subsection Garbage Collextion Routines
+
+/* ---------------------------------------------------------------------------
+ Where are the roots that we know about?
+
+ - all the threads on the runnable queue
+ - all the threads on the blocked queue
+ - all the threads on the sleeping queue
+ - all the thread currently executing a _ccall_GC
+ - all the "main threads"
+
+ ------------------------------------------------------------------------ */
+
+/* This has to be protected either by the scheduler monitor, or by the
+ garbage collection monitor (probably the latter).
+ KH @ 25/10/99
+*/
+
+static void GetRoots(void)
+{
+ StgMainThread *m;
+
+#if defined(GRAN)
+ {
+ nat i;
+ for (i=0; i<=RtsFlags.GranFlags.proc; i++) {
+ if ((run_queue_hds[i] != END_TSO_QUEUE) && ((run_queue_hds[i] != NULL)))
+ run_queue_hds[i] = (StgTSO *)MarkRoot((StgClosure *)run_queue_hds[i]);
+ if ((run_queue_tls[i] != END_TSO_QUEUE) && ((run_queue_tls[i] != NULL)))
+ run_queue_tls[i] = (StgTSO *)MarkRoot((StgClosure *)run_queue_tls[i]);
+
+ if ((blocked_queue_hds[i] != END_TSO_QUEUE) && ((blocked_queue_hds[i] != NULL)))
+ blocked_queue_hds[i] = (StgTSO *)MarkRoot((StgClosure *)blocked_queue_hds[i]);
+ if ((blocked_queue_tls[i] != END_TSO_QUEUE) && ((blocked_queue_tls[i] != NULL)))
+ blocked_queue_tls[i] = (StgTSO *)MarkRoot((StgClosure *)blocked_queue_tls[i]);
+ if ((ccalling_threadss[i] != END_TSO_QUEUE) && ((ccalling_threadss[i] != NULL)))
+ ccalling_threadss[i] = (StgTSO *)MarkRoot((StgClosure *)ccalling_threadss[i]);
+ }
+ }
+
+ markEventQueue();