1 /* ---------------------------------------------------------------------------
3 * (c) The GHC Team, 1998-2004
7 * Different GHC ways use this scheduler quite differently (see comments below)
8 * Here is the global picture:
10 * WAY Name CPP flag What's it for
11 * --------------------------------------
12 * mp GUM PARALLEL_HASKELL Parallel execution on a distrib. memory machine
13 * s SMP SMP Parallel execution on a shared memory machine
14 * mg GranSim GRAN Simulation of parallel execution
15 * md GUM/GdH DIST Distributed execution (based on GUM)
17 * --------------------------------------------------------------------------*/
20 * Version with support for distributed memory parallelism aka GUM (WAY=mp):
22 The main scheduling loop in GUM iterates until a finish message is received.
23 In that case a global flag @receivedFinish@ is set and this instance of
24 the RTS shuts down. See ghc/rts/parallel/HLComms.c:processMessages()
25 for the handling of incoming messages, such as PP_FINISH.
26 Note that in the parallel case we have a system manager that coordinates
27 different PEs, each of which are running one instance of the RTS.
28 See ghc/rts/parallel/SysMan.c for the main routine of the parallel program.
29 From this routine processes executing ghc/rts/Main.c are spawned. -- HWL
31 * Version with support for simulating parallel execution aka GranSim (WAY=mg):
33 The main scheduling code in GranSim is quite different from that in std
34 (concurrent) Haskell: while concurrent Haskell just iterates over the
35 threads in the runnable queue, GranSim is event driven, i.e. it iterates
36 over the events in the global event queue. -- HWL
39 #include "PosixSource.h"
44 #include "BlockAlloc.h"
45 #include "OSThreads.h"
49 #define COMPILING_SCHEDULER
51 #include "StgMiscClosures.h"
52 #include "Interpreter.h"
53 #include "Exception.h"
61 #include "ThreadLabels.h"
62 #include "LdvProfile.h"
65 #include "Proftimer.h"
68 #if defined(GRAN) || defined(PARALLEL_HASKELL)
69 # include "GranSimRts.h"
71 # include "ParallelRts.h"
72 # include "Parallel.h"
73 # include "ParallelDebug.h"
78 #include "Capability.h"
81 #ifdef HAVE_SYS_TYPES_H
82 #include <sys/types.h>
96 // Turn off inlining when debugging - it obfuscates things
99 # define STATIC_INLINE static
103 #define USED_IN_THREADED_RTS
105 #define USED_IN_THREADED_RTS STG_UNUSED
108 #ifdef RTS_SUPPORTS_THREADS
109 #define USED_WHEN_RTS_SUPPORTS_THREADS
111 #define USED_WHEN_RTS_SUPPORTS_THREADS STG_UNUSED
114 /* Main thread queue.
115 * Locks required: sched_mutex.
117 StgMainThread *main_threads = NULL;
121 StgTSO* ActiveTSO = NULL; /* for assigning system costs; GranSim-Light only */
122 /* rtsTime TimeOfNextEvent, EndOfTimeSlice; now in GranSim.c */
125 In GranSim we have a runnable and a blocked queue for each processor.
126 In order to minimise code changes new arrays run_queue_hds/tls
127 are created. run_queue_hd is then a short cut (macro) for
128 run_queue_hds[CurrentProc] (see GranSim.h).
131 StgTSO *run_queue_hds[MAX_PROC], *run_queue_tls[MAX_PROC];
132 StgTSO *blocked_queue_hds[MAX_PROC], *blocked_queue_tls[MAX_PROC];
133 StgTSO *ccalling_threadss[MAX_PROC];
134 /* We use the same global list of threads (all_threads) in GranSim as in
135 the std RTS (i.e. we are cheating). However, we don't use this list in
136 the GranSim specific code at the moment (so we are only potentially
142 * Locks required: sched_mutex.
144 StgTSO *run_queue_hd = NULL;
145 StgTSO *run_queue_tl = NULL;
146 StgTSO *blocked_queue_hd = NULL;
147 StgTSO *blocked_queue_tl = NULL;
148 StgTSO *blackhole_queue = NULL;
149 StgTSO *sleeping_queue = NULL; /* perhaps replace with a hash table? */
153 /* The blackhole_queue should be checked for threads to wake up. See
154 * Schedule.h for more thorough comment.
156 rtsBool blackholes_need_checking = rtsFalse;
158 /* Linked list of all threads.
159 * Used for detecting garbage collected threads.
161 StgTSO *all_threads = NULL;
163 /* When a thread performs a safe C call (_ccall_GC, using old
164 * terminology), it gets put on the suspended_ccalling_threads
165 * list. Used by the garbage collector.
167 static StgTSO *suspended_ccalling_threads;
169 /* KH: The following two flags are shared memory locations. There is no need
170 to lock them, since they are only unset at the end of a scheduler
174 /* flag set by signal handler to precipitate a context switch */
175 int context_switch = 0;
177 /* if this flag is set as well, give up execution */
178 rtsBool interrupted = rtsFalse;
180 /* Next thread ID to allocate.
181 * Locks required: thread_id_mutex
183 static StgThreadID next_thread_id = 1;
186 * Pointers to the state of the current thread.
187 * Rule of thumb: if CurrentTSO != NULL, then we're running a Haskell
188 * thread. If CurrentTSO == NULL, then we're at the scheduler level.
191 /* The smallest stack size that makes any sense is:
192 * RESERVED_STACK_WORDS (so we can get back from the stack overflow)
193 * + sizeofW(StgStopFrame) (the stg_stop_thread_info frame)
194 * + 1 (the closure to enter)
196 * + 1 (spare slot req'd by stg_ap_v_ret)
198 * A thread with this stack will bomb immediately with a stack
199 * overflow, which will increase its stack size.
202 #define MIN_STACK_WORDS (RESERVED_STACK_WORDS + sizeofW(StgStopFrame) + 3)
209 /* This is used in `TSO.h' and gcc 2.96 insists that this variable actually
210 * exists - earlier gccs apparently didn't.
216 * Set to TRUE when entering a shutdown state (via shutdownHaskellAndExit()) --
217 * in an MT setting, needed to signal that a worker thread shouldn't hang around
218 * in the scheduler when it is out of work.
220 static rtsBool shutting_down_scheduler = rtsFalse;
222 #if defined(RTS_SUPPORTS_THREADS)
223 /* ToDo: carefully document the invariants that go together
224 * with these synchronisation objects.
226 Mutex sched_mutex = INIT_MUTEX_VAR;
227 Mutex term_mutex = INIT_MUTEX_VAR;
229 #endif /* RTS_SUPPORTS_THREADS */
231 #if defined(PARALLEL_HASKELL)
233 rtsTime TimeOfLastYield;
234 rtsBool emitSchedule = rtsTrue;
238 static char *whatNext_strs[] = {
248 /* -----------------------------------------------------------------------------
249 * static function prototypes
250 * -------------------------------------------------------------------------- */
252 #if defined(RTS_SUPPORTS_THREADS)
253 static void taskStart(void);
256 static void schedule( StgMainThread *mainThread USED_WHEN_RTS_SUPPORTS_THREADS,
257 Capability *initialCapability );
260 // These function all encapsulate parts of the scheduler loop, and are
261 // abstracted only to make the structure and control flow of the
262 // scheduler clearer.
264 static void schedulePreLoop(void);
265 static void scheduleStartSignalHandlers(void);
266 static void scheduleCheckBlockedThreads(void);
267 static void scheduleCheckBlackHoles(void);
268 static void scheduleDetectDeadlock(void);
270 static StgTSO *scheduleProcessEvent(rtsEvent *event);
272 #if defined(PARALLEL_HASKELL)
273 static StgTSO *scheduleSendPendingMessages(void);
274 static void scheduleActivateSpark(void);
275 static rtsBool scheduleGetRemoteWork(rtsBool *receivedFinish);
277 #if defined(PAR) || defined(GRAN)
278 static void scheduleGranParReport(void);
280 static void schedulePostRunThread(void);
281 static rtsBool scheduleHandleHeapOverflow( Capability *cap, StgTSO *t );
282 static void scheduleHandleStackOverflow( StgTSO *t);
283 static rtsBool scheduleHandleYield( StgTSO *t, nat prev_what_next );
284 static void scheduleHandleThreadBlocked( StgTSO *t );
285 static rtsBool scheduleHandleThreadFinished( StgMainThread *mainThread,
286 Capability *cap, StgTSO *t );
287 static rtsBool scheduleDoHeapProfile(rtsBool ready_to_gc);
288 static void scheduleDoGC(Capability *cap);
290 static void unblockThread(StgTSO *tso);
291 static rtsBool checkBlackHoles(void);
292 static SchedulerStatus waitThread_(/*out*/StgMainThread* m,
293 Capability *initialCapability
295 static void scheduleThread_ (StgTSO* tso);
296 static void AllRoots(evac_fn evac);
298 static StgTSO *threadStackOverflow(StgTSO *tso);
300 static void raiseAsync_(StgTSO *tso, StgClosure *exception,
301 rtsBool stop_at_atomically);
303 static void printThreadBlockage(StgTSO *tso);
304 static void printThreadStatus(StgTSO *tso);
306 #if defined(PARALLEL_HASKELL)
307 StgTSO * createSparkThread(rtsSpark spark);
308 StgTSO * activateSpark (rtsSpark spark);
311 /* ----------------------------------------------------------------------------
313 * ------------------------------------------------------------------------- */
315 #if defined(RTS_SUPPORTS_THREADS)
316 static nat startingWorkerThread = 0;
321 ACQUIRE_LOCK(&sched_mutex);
322 startingWorkerThread--;
325 RELEASE_LOCK(&sched_mutex);
329 startSchedulerTaskIfNecessary(void)
331 if ( !EMPTY_RUN_QUEUE()
332 && !shutting_down_scheduler // not if we're shutting down
333 && startingWorkerThread==0)
335 // we don't want to start another worker thread
336 // just because the last one hasn't yet reached the
337 // "waiting for capability" state
338 startingWorkerThread++;
339 if (!maybeStartNewWorker(taskStart)) {
340 startingWorkerThread--;
346 /* -----------------------------------------------------------------------------
347 * Putting a thread on the run queue: different scheduling policies
348 * -------------------------------------------------------------------------- */
351 addToRunQueue( StgTSO *t )
353 #if defined(PARALLEL_HASKELL)
354 if (RtsFlags.ParFlags.doFairScheduling) {
355 // this does round-robin scheduling; good for concurrency
356 APPEND_TO_RUN_QUEUE(t);
358 // this does unfair scheduling; good for parallelism
359 PUSH_ON_RUN_QUEUE(t);
362 // this does round-robin scheduling; good for concurrency
363 APPEND_TO_RUN_QUEUE(t);
367 /* ---------------------------------------------------------------------------
368 Main scheduling loop.
370 We use round-robin scheduling, each thread returning to the
371 scheduler loop when one of these conditions is detected:
374 * timer expires (thread yields)
379 Locking notes: we acquire the scheduler lock once at the beginning
380 of the scheduler loop, and release it when
382 * running a thread, or
383 * waiting for work, or
384 * waiting for a GC to complete.
387 In a GranSim setup this loop iterates over the global event queue.
388 This revolves around the global event queue, which determines what
389 to do next. Therefore, it's more complicated than either the
390 concurrent or the parallel (GUM) setup.
393 GUM iterates over incoming messages.
394 It starts with nothing to do (thus CurrentTSO == END_TSO_QUEUE),
395 and sends out a fish whenever it has nothing to do; in-between
396 doing the actual reductions (shared code below) it processes the
397 incoming messages and deals with delayed operations
398 (see PendingFetches).
399 This is not the ugliest code you could imagine, but it's bloody close.
401 ------------------------------------------------------------------------ */
404 schedule( StgMainThread *mainThread USED_WHEN_RTS_SUPPORTS_THREADS,
405 Capability *initialCapability )
409 StgThreadReturnCode ret;
412 #elif defined(PARALLEL_HASKELL)
415 rtsBool receivedFinish = rtsFalse;
417 nat tp_size, sp_size; // stats only
423 // Pre-condition: sched_mutex is held.
424 // We might have a capability, passed in as initialCapability.
425 cap = initialCapability;
427 #if !defined(RTS_SUPPORTS_THREADS)
428 // simply initialise it in the non-threaded case
429 grabCapability(&cap);
433 sched_belch("### NEW SCHEDULER LOOP (main thr: %p, cap: %p)",
434 mainThread, initialCapability);
439 // -----------------------------------------------------------
440 // Scheduler loop starts here:
442 #if defined(PARALLEL_HASKELL)
443 #define TERMINATION_CONDITION (!receivedFinish)
445 #define TERMINATION_CONDITION ((event = get_next_event()) != (rtsEvent*)NULL)
447 #define TERMINATION_CONDITION rtsTrue
450 while (TERMINATION_CONDITION) {
453 /* Choose the processor with the next event */
454 CurrentProc = event->proc;
455 CurrentTSO = event->tso;
458 IF_DEBUG(scheduler, printAllThreads());
460 #if defined(RTS_SUPPORTS_THREADS)
461 // Yield the capability to higher-priority tasks if necessary.
464 yieldCapability(&cap);
467 // If we do not currently hold a capability, we wait for one
470 waitForCapability(&sched_mutex, &cap,
471 mainThread ? &mainThread->bound_thread_cond : NULL);
474 // We now have a capability...
477 // Check whether we have re-entered the RTS from Haskell without
478 // going via suspendThread()/resumeThread (i.e. a 'safe' foreign
480 if (cap->r.rInHaskell) {
481 errorBelch("schedule: re-entered unsafely.\n"
482 " Perhaps a 'foreign import unsafe' should be 'safe'?");
487 // Test for interruption. If interrupted==rtsTrue, then either
488 // we received a keyboard interrupt (^C), or the scheduler is
489 // trying to shut down all the tasks (shutting_down_scheduler) in
493 if (shutting_down_scheduler) {
494 IF_DEBUG(scheduler, sched_belch("shutting down"));
495 releaseCapability(cap);
497 mainThread->stat = Interrupted;
498 mainThread->ret = NULL;
502 IF_DEBUG(scheduler, sched_belch("interrupted"));
507 #if defined(not_yet) && defined(SMP)
509 // Top up the run queue from our spark pool. We try to make the
510 // number of threads in the run queue equal to the number of
511 // free capabilities.
515 if (EMPTY_RUN_QUEUE()) {
516 spark = findSpark(rtsFalse);
518 break; /* no more sparks in the pool */
520 createSparkThread(spark);
522 sched_belch("==^^ turning spark of closure %p into a thread",
523 (StgClosure *)spark));
529 scheduleStartSignalHandlers();
531 // Only check the black holes here if we've nothing else to do.
532 // During normal execution, the black hole list only gets checked
533 // at GC time, to avoid repeatedly traversing this possibly long
534 // list each time around the scheduler.
535 if (EMPTY_RUN_QUEUE()) { scheduleCheckBlackHoles(); }
537 scheduleCheckBlockedThreads();
539 scheduleDetectDeadlock();
541 // Normally, the only way we can get here with no threads to
542 // run is if a keyboard interrupt received during
543 // scheduleCheckBlockedThreads() or scheduleDetectDeadlock().
544 // Additionally, it is not fatal for the
545 // threaded RTS to reach here with no threads to run.
547 // win32: might be here due to awaitEvent() being abandoned
548 // as a result of a console event having been delivered.
549 if ( EMPTY_RUN_QUEUE() ) {
550 #if !defined(RTS_SUPPORTS_THREADS) && !defined(mingw32_HOST_OS)
553 continue; // nothing to do
556 #if defined(PARALLEL_HASKELL)
557 scheduleSendPendingMessages();
558 if (EMPTY_RUN_QUEUE() && scheduleActivateSpark())
562 ASSERT(next_fish_to_send_at==0); // i.e. no delayed fishes left!
565 /* If we still have no work we need to send a FISH to get a spark
567 if (EMPTY_RUN_QUEUE()) {
568 if (!scheduleGetRemoteWork(&receivedFinish)) continue;
569 ASSERT(rtsFalse); // should not happen at the moment
571 // from here: non-empty run queue.
572 // TODO: merge above case with this, only one call processMessages() !
573 if (PacketsWaiting()) { /* process incoming messages, if
574 any pending... only in else
575 because getRemoteWork waits for
577 receivedFinish = processMessages();
582 scheduleProcessEvent(event);
586 // Get a thread to run
588 ASSERT(run_queue_hd != END_TSO_QUEUE);
591 #if defined(GRAN) || defined(PAR)
592 scheduleGranParReport(); // some kind of debuging output
594 // Sanity check the thread we're about to run. This can be
595 // expensive if there is lots of thread switching going on...
596 IF_DEBUG(sanity,checkTSO(t));
599 #if defined(RTS_SUPPORTS_THREADS)
600 // Check whether we can run this thread in the current task.
601 // If not, we have to pass our capability to the right task.
603 StgMainThread *m = t->main;
610 sched_belch("### Running thread %d in bound thread", t->id));
611 // yes, the Haskell thread is bound to the current native thread
616 sched_belch("### thread %d bound to another OS thread", t->id));
617 // no, bound to a different Haskell thread: pass to that thread
618 PUSH_ON_RUN_QUEUE(t);
619 passCapability(&m->bound_thread_cond);
625 if(mainThread != NULL)
626 // The thread we want to run is bound.
629 sched_belch("### this OS thread cannot run thread %d", t->id));
630 // no, the current native thread is bound to a different
631 // Haskell thread, so pass it to any worker thread
632 PUSH_ON_RUN_QUEUE(t);
633 passCapabilityToWorker();
640 cap->r.rCurrentTSO = t;
642 /* context switches are now initiated by the timer signal, unless
643 * the user specified "context switch as often as possible", with
646 if ((RtsFlags.ConcFlags.ctxtSwitchTicks == 0
647 && (run_queue_hd != END_TSO_QUEUE
648 || blocked_queue_hd != END_TSO_QUEUE
649 || sleeping_queue != END_TSO_QUEUE)))
654 RELEASE_LOCK(&sched_mutex);
656 IF_DEBUG(scheduler, sched_belch("-->> running thread %ld %s ...",
657 (long)t->id, whatNext_strs[t->what_next]));
659 #if defined(PROFILING)
660 startHeapProfTimer();
663 // ----------------------------------------------------------------------
664 // Run the current thread
666 prev_what_next = t->what_next;
668 errno = t->saved_errno;
669 cap->r.rInHaskell = rtsTrue;
671 switch (prev_what_next) {
675 /* Thread already finished, return to scheduler. */
676 ret = ThreadFinished;
680 ret = StgRun((StgFunPtr) stg_returnToStackTop, &cap->r);
683 case ThreadInterpret:
684 ret = interpretBCO(cap);
688 barf("schedule: invalid what_next field");
691 // We have run some Haskell code: there might be blackhole-blocked
692 // threads to wake up now.
693 if ( blackhole_queue != END_TSO_QUEUE ) {
694 blackholes_need_checking = rtsTrue;
697 cap->r.rInHaskell = rtsFalse;
699 // The TSO might have moved, eg. if it re-entered the RTS and a GC
700 // happened. So find the new location:
701 t = cap->r.rCurrentTSO;
703 // And save the current errno in this thread.
704 t->saved_errno = errno;
706 // ----------------------------------------------------------------------
708 /* Costs for the scheduler are assigned to CCS_SYSTEM */
709 #if defined(PROFILING)
714 ACQUIRE_LOCK(&sched_mutex);
716 #if defined(RTS_SUPPORTS_THREADS)
717 IF_DEBUG(scheduler,debugBelch("sched (task %p): ", osThreadId()););
718 #elif !defined(GRAN) && !defined(PARALLEL_HASKELL)
719 IF_DEBUG(scheduler,debugBelch("sched: "););
722 schedulePostRunThread();
724 ready_to_gc = rtsFalse;
728 ready_to_gc = scheduleHandleHeapOverflow(cap,t);
732 scheduleHandleStackOverflow(t);
736 if (scheduleHandleYield(t, prev_what_next)) {
737 // shortcut for switching between compiler/interpreter:
743 scheduleHandleThreadBlocked(t);
748 if (scheduleHandleThreadFinished(mainThread, cap, t)) return;;
752 barf("schedule: invalid thread return code %d", (int)ret);
755 if (scheduleDoHeapProfile(ready_to_gc)) { ready_to_gc = rtsFalse; }
756 if (ready_to_gc) { scheduleDoGC(cap); }
757 } /* end of while() */
759 IF_PAR_DEBUG(verbose,
760 debugBelch("== Leaving schedule() after having received Finish\n"));
763 /* ----------------------------------------------------------------------------
764 * Setting up the scheduler loop
765 * ASSUMES: sched_mutex
766 * ------------------------------------------------------------------------- */
769 schedulePreLoop(void)
772 /* set up first event to get things going */
773 /* ToDo: assign costs for system setup and init MainTSO ! */
774 new_event(CurrentProc, CurrentProc, CurrentTime[CurrentProc],
776 CurrentTSO, (StgClosure*)NULL, (rtsSpark*)NULL);
779 debugBelch("GRAN: Init CurrentTSO (in schedule) = %p\n",
781 G_TSO(CurrentTSO, 5));
783 if (RtsFlags.GranFlags.Light) {
784 /* Save current time; GranSim Light only */
785 CurrentTSO->gran.clock = CurrentTime[CurrentProc];
790 /* ----------------------------------------------------------------------------
791 * Start any pending signal handlers
792 * ASSUMES: sched_mutex
793 * ------------------------------------------------------------------------- */
796 scheduleStartSignalHandlers(void)
798 #if defined(RTS_USER_SIGNALS) && !defined(RTS_SUPPORTS_THREADS)
799 if (signals_pending()) {
800 RELEASE_LOCK(&sched_mutex); /* ToDo: kill */
801 startSignalHandlers();
802 ACQUIRE_LOCK(&sched_mutex);
807 /* ----------------------------------------------------------------------------
808 * Check for blocked threads that can be woken up.
809 * ASSUMES: sched_mutex
810 * ------------------------------------------------------------------------- */
813 scheduleCheckBlockedThreads(void)
816 // Check whether any waiting threads need to be woken up. If the
817 // run queue is empty, and there are no other tasks running, we
818 // can wait indefinitely for something to happen.
820 if ( !EMPTY_QUEUE(blocked_queue_hd) || !EMPTY_QUEUE(sleeping_queue) )
822 #if defined(RTS_SUPPORTS_THREADS)
823 // We shouldn't be here...
824 barf("schedule: awaitEvent() in threaded RTS");
826 awaitEvent( EMPTY_RUN_QUEUE() && !blackholes_need_checking );
831 /* ----------------------------------------------------------------------------
832 * Check for threads blocked on BLACKHOLEs that can be woken up
833 * ASSUMES: sched_mutex
834 * ------------------------------------------------------------------------- */
836 scheduleCheckBlackHoles( void )
838 if ( blackholes_need_checking )
841 blackholes_need_checking = rtsFalse;
845 /* ----------------------------------------------------------------------------
846 * Detect deadlock conditions and attempt to resolve them.
847 * ASSUMES: sched_mutex
848 * ------------------------------------------------------------------------- */
851 scheduleDetectDeadlock(void)
854 * Detect deadlock: when we have no threads to run, there are no
855 * threads blocked, waiting for I/O, or sleeping, and all the
856 * other tasks are waiting for work, we must have a deadlock of
859 if ( EMPTY_THREAD_QUEUES() )
861 #if !defined(PARALLEL_HASKELL) && !defined(RTS_SUPPORTS_THREADS)
862 IF_DEBUG(scheduler, sched_belch("deadlocked, forcing major GC..."));
864 // Garbage collection can release some new threads due to
865 // either (a) finalizers or (b) threads resurrected because
866 // they are unreachable and will therefore be sent an
867 // exception. Any threads thus released will be immediately
869 GarbageCollect(GetRoots,rtsTrue);
870 if ( !EMPTY_RUN_QUEUE() ) return;
872 #if defined(RTS_USER_SIGNALS)
873 /* If we have user-installed signal handlers, then wait
874 * for signals to arrive rather then bombing out with a
877 if ( anyUserHandlers() ) {
879 sched_belch("still deadlocked, waiting for signals..."));
883 if (signals_pending()) {
884 RELEASE_LOCK(&sched_mutex);
885 startSignalHandlers();
886 ACQUIRE_LOCK(&sched_mutex);
889 // either we have threads to run, or we were interrupted:
890 ASSERT(!EMPTY_RUN_QUEUE() || interrupted);
894 /* Probably a real deadlock. Send the current main thread the
895 * Deadlock exception (or in the SMP build, send *all* main
896 * threads the deadlock exception, since none of them can make
902 switch (m->tso->why_blocked) {
903 case BlockedOnBlackHole:
904 case BlockedOnException:
906 raiseAsync(m->tso, (StgClosure *)NonTermination_closure);
909 barf("deadlock: main thread blocked in a strange way");
913 #elif defined(RTS_SUPPORTS_THREADS)
914 // ToDo: add deadlock detection in threaded RTS
915 #elif defined(PARALLEL_HASKELL)
916 // ToDo: add deadlock detection in GUM (similar to SMP) -- HWL
921 /* ----------------------------------------------------------------------------
922 * Process an event (GRAN only)
923 * ------------------------------------------------------------------------- */
927 scheduleProcessEvent(rtsEvent *event)
931 if (RtsFlags.GranFlags.Light)
932 GranSimLight_enter_system(event, &ActiveTSO); // adjust ActiveTSO etc
934 /* adjust time based on time-stamp */
935 if (event->time > CurrentTime[CurrentProc] &&
936 event->evttype != ContinueThread)
937 CurrentTime[CurrentProc] = event->time;
939 /* Deal with the idle PEs (may issue FindWork or MoveSpark events) */
940 if (!RtsFlags.GranFlags.Light)
943 IF_DEBUG(gran, debugBelch("GRAN: switch by event-type\n"));
945 /* main event dispatcher in GranSim */
946 switch (event->evttype) {
947 /* Should just be continuing execution */
949 IF_DEBUG(gran, debugBelch("GRAN: doing ContinueThread\n"));
950 /* ToDo: check assertion
951 ASSERT(run_queue_hd != (StgTSO*)NULL &&
952 run_queue_hd != END_TSO_QUEUE);
954 /* Ignore ContinueThreads for fetching threads (if synchr comm) */
955 if (!RtsFlags.GranFlags.DoAsyncFetch &&
956 procStatus[CurrentProc]==Fetching) {
957 debugBelch("ghuH: Spurious ContinueThread while Fetching ignored; TSO %d (%p) [PE %d]\n",
958 CurrentTSO->id, CurrentTSO, CurrentProc);
961 /* Ignore ContinueThreads for completed threads */
962 if (CurrentTSO->what_next == ThreadComplete) {
963 debugBelch("ghuH: found a ContinueThread event for completed thread %d (%p) [PE %d] (ignoring ContinueThread)\n",
964 CurrentTSO->id, CurrentTSO, CurrentProc);
967 /* Ignore ContinueThreads for threads that are being migrated */
968 if (PROCS(CurrentTSO)==Nowhere) {
969 debugBelch("ghuH: trying to run the migrating TSO %d (%p) [PE %d] (ignoring ContinueThread)\n",
970 CurrentTSO->id, CurrentTSO, CurrentProc);
973 /* The thread should be at the beginning of the run queue */
974 if (CurrentTSO!=run_queue_hds[CurrentProc]) {
975 debugBelch("ghuH: TSO %d (%p) [PE %d] is not at the start of the run_queue when doing a ContinueThread\n",
976 CurrentTSO->id, CurrentTSO, CurrentProc);
977 break; // run the thread anyway
980 new_event(proc, proc, CurrentTime[proc],
982 (StgTSO*)NULL, (StgClosure*)NULL, (rtsSpark*)NULL);
984 */ /* Catches superfluous CONTINUEs -- should be unnecessary */
985 break; // now actually run the thread; DaH Qu'vam yImuHbej
988 do_the_fetchnode(event);
989 goto next_thread; /* handle next event in event queue */
992 do_the_globalblock(event);
993 goto next_thread; /* handle next event in event queue */
996 do_the_fetchreply(event);
997 goto next_thread; /* handle next event in event queue */
999 case UnblockThread: /* Move from the blocked queue to the tail of */
1000 do_the_unblock(event);
1001 goto next_thread; /* handle next event in event queue */
1003 case ResumeThread: /* Move from the blocked queue to the tail of */
1004 /* the runnable queue ( i.e. Qu' SImqa'lu') */
1005 event->tso->gran.blocktime +=
1006 CurrentTime[CurrentProc] - event->tso->gran.blockedat;
1007 do_the_startthread(event);
1008 goto next_thread; /* handle next event in event queue */
1011 do_the_startthread(event);
1012 goto next_thread; /* handle next event in event queue */
1015 do_the_movethread(event);
1016 goto next_thread; /* handle next event in event queue */
1019 do_the_movespark(event);
1020 goto next_thread; /* handle next event in event queue */
1023 do_the_findwork(event);
1024 goto next_thread; /* handle next event in event queue */
1027 barf("Illegal event type %u\n", event->evttype);
1030 /* This point was scheduler_loop in the old RTS */
1032 IF_DEBUG(gran, debugBelch("GRAN: after main switch\n"));
1034 TimeOfLastEvent = CurrentTime[CurrentProc];
1035 TimeOfNextEvent = get_time_of_next_event();
1036 IgnoreEvents=(TimeOfNextEvent==0); // HWL HACK
1037 // CurrentTSO = ThreadQueueHd;
1039 IF_DEBUG(gran, debugBelch("GRAN: time of next event is: %ld\n",
1042 if (RtsFlags.GranFlags.Light)
1043 GranSimLight_leave_system(event, &ActiveTSO);
1045 EndOfTimeSlice = CurrentTime[CurrentProc]+RtsFlags.GranFlags.time_slice;
1048 debugBelch("GRAN: end of time-slice is %#lx\n", EndOfTimeSlice));
1050 /* in a GranSim setup the TSO stays on the run queue */
1052 /* Take a thread from the run queue. */
1053 POP_RUN_QUEUE(t); // take_off_run_queue(t);
1056 debugBelch("GRAN: About to run current thread, which is\n");
1059 context_switch = 0; // turned on via GranYield, checking events and time slice
1062 DumpGranEvent(GR_SCHEDULE, t));
1064 procStatus[CurrentProc] = Busy;
1068 /* ----------------------------------------------------------------------------
1069 * Send pending messages (PARALLEL_HASKELL only)
1070 * ------------------------------------------------------------------------- */
1072 #if defined(PARALLEL_HASKELL)
1074 scheduleSendPendingMessages(void)
1080 # if defined(PAR) // global Mem.Mgmt., omit for now
1081 if (PendingFetches != END_BF_QUEUE) {
1086 if (RtsFlags.ParFlags.BufferTime) {
1087 // if we use message buffering, we must send away all message
1088 // packets which have become too old...
1094 /* ----------------------------------------------------------------------------
1095 * Activate spark threads (PARALLEL_HASKELL only)
1096 * ------------------------------------------------------------------------- */
1098 #if defined(PARALLEL_HASKELL)
1100 scheduleActivateSpark(void)
1103 ASSERT(EMPTY_RUN_QUEUE());
1104 /* We get here if the run queue is empty and want some work.
1105 We try to turn a spark into a thread, and add it to the run queue,
1106 from where it will be picked up in the next iteration of the scheduler
1110 /* :-[ no local threads => look out for local sparks */
1111 /* the spark pool for the current PE */
1112 pool = &(cap.r.rSparks); // JB: cap = (old) MainCap
1113 if (advisory_thread_count < RtsFlags.ParFlags.maxThreads &&
1114 pool->hd < pool->tl) {
1116 * ToDo: add GC code check that we really have enough heap afterwards!!
1118 * If we're here (no runnable threads) and we have pending
1119 * sparks, we must have a space problem. Get enough space
1120 * to turn one of those pending sparks into a
1124 spark = findSpark(rtsFalse); /* get a spark */
1125 if (spark != (rtsSpark) NULL) {
1126 tso = createThreadFromSpark(spark); /* turn the spark into a thread */
1127 IF_PAR_DEBUG(fish, // schedule,
1128 debugBelch("==== schedule: Created TSO %d (%p); %d threads active\n",
1129 tso->id, tso, advisory_thread_count));
1131 if (tso==END_TSO_QUEUE) { /* failed to activate spark->back to loop */
1132 IF_PAR_DEBUG(fish, // schedule,
1133 debugBelch("==^^ failed to create thread from spark @ %lx\n",
1135 return rtsFalse; /* failed to generate a thread */
1136 } /* otherwise fall through & pick-up new tso */
1138 IF_PAR_DEBUG(fish, // schedule,
1139 debugBelch("==^^ no local sparks (spark pool contains only NFs: %d)\n",
1140 spark_queue_len(pool)));
1141 return rtsFalse; /* failed to generate a thread */
1143 return rtsTrue; /* success in generating a thread */
1144 } else { /* no more threads permitted or pool empty */
1145 return rtsFalse; /* failed to generateThread */
1148 tso = NULL; // avoid compiler warning only
1149 return rtsFalse; /* dummy in non-PAR setup */
1152 #endif // PARALLEL_HASKELL
1154 /* ----------------------------------------------------------------------------
1155 * Get work from a remote node (PARALLEL_HASKELL only)
1156 * ------------------------------------------------------------------------- */
1158 #if defined(PARALLEL_HASKELL)
1160 scheduleGetRemoteWork(rtsBool *receivedFinish)
1162 ASSERT(EMPTY_RUN_QUEUE());
1164 if (RtsFlags.ParFlags.BufferTime) {
1165 IF_PAR_DEBUG(verbose,
1166 debugBelch("...send all pending data,"));
1169 for (i=1; i<=nPEs; i++)
1170 sendImmediately(i); // send all messages away immediately
1174 //++EDEN++ idle() , i.e. send all buffers, wait for work
1175 // suppress fishing in EDEN... just look for incoming messages
1176 // (blocking receive)
1177 IF_PAR_DEBUG(verbose,
1178 debugBelch("...wait for incoming messages...\n"));
1179 *receivedFinish = processMessages(); // blocking receive...
1181 // and reenter scheduling loop after having received something
1182 // (return rtsFalse below)
1184 # else /* activate SPARKS machinery */
1185 /* We get here, if we have no work, tried to activate a local spark, but still
1186 have no work. We try to get a remote spark, by sending a FISH message.
1187 Thread migration should be added here, and triggered when a sequence of
1188 fishes returns without work. */
1189 delay = (RtsFlags.ParFlags.fishDelay!=0ll ? RtsFlags.ParFlags.fishDelay : 0ll);
1191 /* =8-[ no local sparks => look for work on other PEs */
1193 * We really have absolutely no work. Send out a fish
1194 * (there may be some out there already), and wait for
1195 * something to arrive. We clearly can't run any threads
1196 * until a SCHEDULE or RESUME arrives, and so that's what
1197 * we're hoping to see. (Of course, we still have to
1198 * respond to other types of messages.)
1200 rtsTime now = msTime() /*CURRENT_TIME*/;
1201 IF_PAR_DEBUG(verbose,
1202 debugBelch("-- now=%ld\n", now));
1203 IF_PAR_DEBUG(fish, // verbose,
1204 if (outstandingFishes < RtsFlags.ParFlags.maxFishes &&
1205 (last_fish_arrived_at!=0 &&
1206 last_fish_arrived_at+delay > now)) {
1207 debugBelch("--$$ <%llu> delaying FISH until %llu (last fish %llu, delay %llu)\n",
1208 now, last_fish_arrived_at+delay,
1209 last_fish_arrived_at,
1213 if (outstandingFishes < RtsFlags.ParFlags.maxFishes &&
1214 advisory_thread_count < RtsFlags.ParFlags.maxThreads) { // send a FISH, but when?
1215 if (last_fish_arrived_at==0 ||
1216 (last_fish_arrived_at+delay <= now)) { // send FISH now!
1217 /* outstandingFishes is set in sendFish, processFish;
1218 avoid flooding system with fishes via delay */
1219 next_fish_to_send_at = 0;
1221 /* ToDo: this should be done in the main scheduling loop to avoid the
1222 busy wait here; not so bad if fish delay is very small */
1223 int iq = 0; // DEBUGGING -- HWL
1224 next_fish_to_send_at = last_fish_arrived_at+delay; // remember when to send
1225 /* send a fish when ready, but process messages that arrive in the meantime */
1227 if (PacketsWaiting()) {
1229 *receivedFinish = processMessages();
1232 } while (!*receivedFinish || now<next_fish_to_send_at);
1233 // JB: This means the fish could become obsolete, if we receive
1234 // work. Better check for work again?
1235 // last line: while (!receivedFinish || !haveWork || now<...)
1236 // next line: if (receivedFinish || haveWork )
1238 if (*receivedFinish) // no need to send a FISH if we are finishing anyway
1239 return rtsFalse; // NB: this will leave scheduler loop
1240 // immediately after return!
1242 IF_PAR_DEBUG(fish, // verbose,
1243 debugBelch("--$$ <%llu> sent delayed fish (%d processMessages); active/total threads=%d/%d\n",now,iq,run_queue_len(),advisory_thread_count));
1247 // JB: IMHO, this should all be hidden inside sendFish(...)
1249 sendFish(pe, thisPE, NEW_FISH_AGE, NEW_FISH_HISTORY,
1252 // Global statistics: count no. of fishes
1253 if (RtsFlags.ParFlags.ParStats.Global &&
1254 RtsFlags.GcFlags.giveStats > NO_GC_STATS) {
1255 globalParStats.tot_fish_mess++;
1259 /* delayed fishes must have been sent by now! */
1260 next_fish_to_send_at = 0;
1263 *receivedFinish = processMessages();
1264 # endif /* SPARKS */
1267 /* NB: this function always returns rtsFalse, meaning the scheduler
1268 loop continues with the next iteration;
1270 return code means success in finding work; we enter this function
1271 if there is no local work, thus have to send a fish which takes
1272 time until it arrives with work; in the meantime we should process
1273 messages in the main loop;
1276 #endif // PARALLEL_HASKELL
1278 /* ----------------------------------------------------------------------------
1279 * PAR/GRAN: Report stats & debugging info(?)
1280 * ------------------------------------------------------------------------- */
1282 #if defined(PAR) || defined(GRAN)
1284 scheduleGranParReport(void)
1286 ASSERT(run_queue_hd != END_TSO_QUEUE);
1288 /* Take a thread from the run queue, if we have work */
1289 POP_RUN_QUEUE(t); // take_off_run_queue(END_TSO_QUEUE);
1291 /* If this TSO has got its outport closed in the meantime,
1292 * it mustn't be run. Instead, we have to clean it up as if it was finished.
1293 * It has to be marked as TH_DEAD for this purpose.
1294 * If it is TH_TERM instead, it is supposed to have finished in the normal way.
1296 JB: TODO: investigate wether state change field could be nuked
1297 entirely and replaced by the normal tso state (whatnext
1298 field). All we want to do is to kill tsos from outside.
1301 /* ToDo: write something to the log-file
1302 if (RTSflags.ParFlags.granSimStats && !sameThread)
1303 DumpGranEvent(GR_SCHEDULE, RunnableThreadsHd);
1307 /* the spark pool for the current PE */
1308 pool = &(cap.r.rSparks); // cap = (old) MainCap
1311 debugBelch("--=^ %d threads, %d sparks on [%#x]\n",
1312 run_queue_len(), spark_queue_len(pool), CURRENT_PROC));
1315 debugBelch("--=^ %d threads, %d sparks on [%#x]\n",
1316 run_queue_len(), spark_queue_len(pool), CURRENT_PROC));
1318 if (RtsFlags.ParFlags.ParStats.Full &&
1319 (t->par.sparkname != (StgInt)0) && // only log spark generated threads
1320 (emitSchedule || // forced emit
1321 (t && LastTSO && t->id != LastTSO->id))) {
1323 we are running a different TSO, so write a schedule event to log file
1324 NB: If we use fair scheduling we also have to write a deschedule
1325 event for LastTSO; with unfair scheduling we know that the
1326 previous tso has blocked whenever we switch to another tso, so
1327 we don't need it in GUM for now
1329 IF_PAR_DEBUG(fish, // schedule,
1330 debugBelch("____ scheduling spark generated thread %d (%lx) (%lx) via a forced emit\n",t->id,t,t->par.sparkname));
1332 DumpRawGranEvent(CURRENT_PROC, CURRENT_PROC,
1333 GR_SCHEDULE, t, (StgClosure *)NULL, 0, 0);
1334 emitSchedule = rtsFalse;
1339 /* ----------------------------------------------------------------------------
1340 * After running a thread...
1341 * ASSUMES: sched_mutex
1342 * ------------------------------------------------------------------------- */
1345 schedulePostRunThread(void)
1348 /* HACK 675: if the last thread didn't yield, make sure to print a
1349 SCHEDULE event to the log file when StgRunning the next thread, even
1350 if it is the same one as before */
1352 TimeOfLastYield = CURRENT_TIME;
1355 /* some statistics gathering in the parallel case */
1357 #if defined(GRAN) || defined(PAR) || defined(EDEN)
1361 IF_DEBUG(gran, DumpGranEvent(GR_DESCHEDULE, t));
1362 globalGranStats.tot_heapover++;
1364 globalParStats.tot_heapover++;
1371 DumpGranEvent(GR_DESCHEDULE, t));
1372 globalGranStats.tot_stackover++;
1375 // DumpGranEvent(GR_DESCHEDULE, t);
1376 globalParStats.tot_stackover++;
1380 case ThreadYielding:
1383 DumpGranEvent(GR_DESCHEDULE, t));
1384 globalGranStats.tot_yields++;
1387 // DumpGranEvent(GR_DESCHEDULE, t);
1388 globalParStats.tot_yields++;
1395 debugBelch("--<< thread %ld (%p; %s) stopped, blocking on node %p [PE %d] with BQ: ",
1396 t->id, t, whatNext_strs[t->what_next], t->block_info.closure,
1397 (t->block_info.closure==(StgClosure*)NULL ? 99 : where_is(t->block_info.closure)));
1398 if (t->block_info.closure!=(StgClosure*)NULL)
1399 print_bq(t->block_info.closure);
1402 // ??? needed; should emit block before
1404 DumpGranEvent(GR_DESCHEDULE, t));
1405 prune_eventq(t, (StgClosure *)NULL); // prune ContinueThreads for t
1408 ASSERT(procStatus[CurrentProc]==Busy ||
1409 ((procStatus[CurrentProc]==Fetching) &&
1410 (t->block_info.closure!=(StgClosure*)NULL)));
1411 if (run_queue_hds[CurrentProc] == END_TSO_QUEUE &&
1412 !(!RtsFlags.GranFlags.DoAsyncFetch &&
1413 procStatus[CurrentProc]==Fetching))
1414 procStatus[CurrentProc] = Idle;
1417 //++PAR++ blockThread() writes the event (change?)
1421 case ThreadFinished:
1425 barf("parGlobalStats: unknown return code");
1431 /* -----------------------------------------------------------------------------
1432 * Handle a thread that returned to the scheduler with ThreadHeepOverflow
1433 * ASSUMES: sched_mutex
1434 * -------------------------------------------------------------------------- */
1437 scheduleHandleHeapOverflow( Capability *cap, StgTSO *t )
1439 // did the task ask for a large block?
1440 if (cap->r.rHpAlloc > BLOCK_SIZE) {
1441 // if so, get one and push it on the front of the nursery.
1445 blocks = (lnat)BLOCK_ROUND_UP(cap->r.rHpAlloc) / BLOCK_SIZE;
1448 debugBelch("--<< thread %ld (%s) stopped: requesting a large block (size %ld)\n",
1449 (long)t->id, whatNext_strs[t->what_next], blocks));
1451 // don't do this if it would push us over the
1452 // alloc_blocks_lim limit; we'll GC first.
1453 if (alloc_blocks + blocks < alloc_blocks_lim) {
1455 alloc_blocks += blocks;
1456 bd = allocGroup( blocks );
1458 // link the new group into the list
1459 bd->link = cap->r.rCurrentNursery;
1460 bd->u.back = cap->r.rCurrentNursery->u.back;
1461 if (cap->r.rCurrentNursery->u.back != NULL) {
1462 cap->r.rCurrentNursery->u.back->link = bd;
1465 ASSERT(g0s0->blocks == cap->r.rCurrentNursery &&
1466 g0s0->blocks == cap->r.rNursery);
1469 cap->r.rNursery->blocks = bd;
1471 cap->r.rCurrentNursery->u.back = bd;
1473 // initialise it as a nursery block. We initialise the
1474 // step, gen_no, and flags field of *every* sub-block in
1475 // this large block, because this is easier than making
1476 // sure that we always find the block head of a large
1477 // block whenever we call Bdescr() (eg. evacuate() and
1478 // isAlive() in the GC would both have to do this, at
1482 for (x = bd; x < bd + blocks; x++) {
1490 // don't forget to update the block count in g0s0.
1491 g0s0->n_blocks += blocks;
1493 // This assert can be a killer if the app is doing lots
1494 // of large block allocations.
1495 ASSERT(countBlocks(g0s0->blocks) == g0s0->n_blocks);
1498 // now update the nursery to point to the new block
1499 cap->r.rCurrentNursery = bd;
1501 // we might be unlucky and have another thread get on the
1502 // run queue before us and steal the large block, but in that
1503 // case the thread will just end up requesting another large
1505 PUSH_ON_RUN_QUEUE(t);
1506 return rtsFalse; /* not actually GC'ing */
1510 /* make all the running tasks block on a condition variable,
1511 * maybe set context_switch and wait till they all pile in,
1512 * then have them wait on a GC condition variable.
1515 debugBelch("--<< thread %ld (%s) stopped: HeapOverflow\n",
1516 (long)t->id, whatNext_strs[t->what_next]));
1519 ASSERT(!is_on_queue(t,CurrentProc));
1520 #elif defined(PARALLEL_HASKELL)
1521 /* Currently we emit a DESCHEDULE event before GC in GUM.
1522 ToDo: either add separate event to distinguish SYSTEM time from rest
1523 or just nuke this DESCHEDULE (and the following SCHEDULE) */
1524 if (0 && RtsFlags.ParFlags.ParStats.Full) {
1525 DumpRawGranEvent(CURRENT_PROC, CURRENT_PROC,
1526 GR_DESCHEDULE, t, (StgClosure *)NULL, 0, 0);
1527 emitSchedule = rtsTrue;
1531 PUSH_ON_RUN_QUEUE(t);
1533 /* actual GC is done at the end of the while loop in schedule() */
1536 /* -----------------------------------------------------------------------------
1537 * Handle a thread that returned to the scheduler with ThreadStackOverflow
1538 * ASSUMES: sched_mutex
1539 * -------------------------------------------------------------------------- */
1542 scheduleHandleStackOverflow( StgTSO *t)
1544 IF_DEBUG(scheduler,debugBelch("--<< thread %ld (%s) stopped, StackOverflow\n",
1545 (long)t->id, whatNext_strs[t->what_next]));
1546 /* just adjust the stack for this thread, then pop it back
1551 /* enlarge the stack */
1552 StgTSO *new_t = threadStackOverflow(t);
1554 /* This TSO has moved, so update any pointers to it from the
1555 * main thread stack. It better not be on any other queues...
1556 * (it shouldn't be).
1558 if (t->main != NULL) {
1559 t->main->tso = new_t;
1561 PUSH_ON_RUN_QUEUE(new_t);
1565 /* -----------------------------------------------------------------------------
1566 * Handle a thread that returned to the scheduler with ThreadYielding
1567 * ASSUMES: sched_mutex
1568 * -------------------------------------------------------------------------- */
1571 scheduleHandleYield( StgTSO *t, nat prev_what_next )
1573 // Reset the context switch flag. We don't do this just before
1574 // running the thread, because that would mean we would lose ticks
1575 // during GC, which can lead to unfair scheduling (a thread hogs
1576 // the CPU because the tick always arrives during GC). This way
1577 // penalises threads that do a lot of allocation, but that seems
1578 // better than the alternative.
1581 /* put the thread back on the run queue. Then, if we're ready to
1582 * GC, check whether this is the last task to stop. If so, wake
1583 * up the GC thread. getThread will block during a GC until the
1587 if (t->what_next != prev_what_next) {
1588 debugBelch("--<< thread %ld (%s) stopped to switch evaluators\n",
1589 (long)t->id, whatNext_strs[t->what_next]);
1591 debugBelch("--<< thread %ld (%s) stopped, yielding\n",
1592 (long)t->id, whatNext_strs[t->what_next]);
1597 //debugBelch("&& Doing sanity check on yielding TSO %ld.", t->id);
1599 ASSERT(t->link == END_TSO_QUEUE);
1601 // Shortcut if we're just switching evaluators: don't bother
1602 // doing stack squeezing (which can be expensive), just run the
1604 if (t->what_next != prev_what_next) {
1611 ASSERT(!is_on_queue(t,CurrentProc));
1614 //debugBelch("&& Doing sanity check on all ThreadQueues (and their TSOs).");
1615 checkThreadQsSanity(rtsTrue));
1622 /* add a ContinueThread event to actually process the thread */
1623 new_event(CurrentProc, CurrentProc, CurrentTime[CurrentProc],
1625 t, (StgClosure*)NULL, (rtsSpark*)NULL);
1627 debugBelch("GRAN: eventq and runnableq after adding yielded thread to queue again:\n");
1634 /* -----------------------------------------------------------------------------
1635 * Handle a thread that returned to the scheduler with ThreadBlocked
1636 * ASSUMES: sched_mutex
1637 * -------------------------------------------------------------------------- */
1640 scheduleHandleThreadBlocked( StgTSO *t
1641 #if !defined(GRAN) && !defined(DEBUG)
1648 debugBelch("--<< thread %ld (%p; %s) stopped, blocking on node %p [PE %d] with BQ: \n",
1649 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)));
1650 if (t->block_info.closure!=(StgClosure*)NULL) print_bq(t->block_info.closure));
1652 // ??? needed; should emit block before
1654 DumpGranEvent(GR_DESCHEDULE, t));
1655 prune_eventq(t, (StgClosure *)NULL); // prune ContinueThreads for t
1658 ASSERT(procStatus[CurrentProc]==Busy ||
1659 ((procStatus[CurrentProc]==Fetching) &&
1660 (t->block_info.closure!=(StgClosure*)NULL)));
1661 if (run_queue_hds[CurrentProc] == END_TSO_QUEUE &&
1662 !(!RtsFlags.GranFlags.DoAsyncFetch &&
1663 procStatus[CurrentProc]==Fetching))
1664 procStatus[CurrentProc] = Idle;
1668 debugBelch("--<< thread %ld (%p; %s) stopped, blocking on node %p with BQ: \n",
1669 t->id, t, whatNext_strs[t->what_next], t->block_info.closure));
1672 if (t->block_info.closure!=(StgClosure*)NULL)
1673 print_bq(t->block_info.closure));
1675 /* Send a fetch (if BlockedOnGA) and dump event to log file */
1678 /* whatever we schedule next, we must log that schedule */
1679 emitSchedule = rtsTrue;
1682 /* don't need to do anything. Either the thread is blocked on
1683 * I/O, in which case we'll have called addToBlockedQueue
1684 * previously, or it's blocked on an MVar or Blackhole, in which
1685 * case it'll be on the relevant queue already.
1687 ASSERT(t->why_blocked != NotBlocked);
1689 debugBelch("--<< thread %d (%s) stopped: ",
1690 t->id, whatNext_strs[t->what_next]);
1691 printThreadBlockage(t);
1694 /* Only for dumping event to log file
1695 ToDo: do I need this in GranSim, too?
1701 /* -----------------------------------------------------------------------------
1702 * Handle a thread that returned to the scheduler with ThreadFinished
1703 * ASSUMES: sched_mutex
1704 * -------------------------------------------------------------------------- */
1707 scheduleHandleThreadFinished( StgMainThread *mainThread
1708 USED_WHEN_RTS_SUPPORTS_THREADS,
1712 /* Need to check whether this was a main thread, and if so,
1713 * return with the return value.
1715 * We also end up here if the thread kills itself with an
1716 * uncaught exception, see Exception.cmm.
1718 IF_DEBUG(scheduler,debugBelch("--++ thread %d (%s) finished\n",
1719 t->id, whatNext_strs[t->what_next]));
1722 endThread(t, CurrentProc); // clean-up the thread
1723 #elif defined(PARALLEL_HASKELL)
1724 /* For now all are advisory -- HWL */
1725 //if(t->priority==AdvisoryPriority) ??
1726 advisory_thread_count--; // JB: Caution with this counter, buggy!
1729 if(t->dist.priority==RevalPriority)
1733 # if defined(EDENOLD)
1734 // the thread could still have an outport... (BUG)
1735 if (t->eden.outport != -1) {
1736 // delete the outport for the tso which has finished...
1737 IF_PAR_DEBUG(eden_ports,
1738 debugBelch("WARNING: Scheduler removes outport %d for TSO %d.\n",
1739 t->eden.outport, t->id));
1742 // thread still in the process (HEAVY BUG! since outport has just been closed...)
1743 if (t->eden.epid != -1) {
1744 IF_PAR_DEBUG(eden_ports,
1745 debugBelch("WARNING: Scheduler removes TSO %d from process %d .\n",
1746 t->id, t->eden.epid));
1747 removeTSOfromProcess(t);
1752 if (RtsFlags.ParFlags.ParStats.Full &&
1753 !RtsFlags.ParFlags.ParStats.Suppressed)
1754 DumpEndEvent(CURRENT_PROC, t, rtsFalse /* not mandatory */);
1756 // t->par only contains statistics: left out for now...
1758 debugBelch("**** end thread: ended sparked thread %d (%lx); sparkname: %lx\n",
1759 t->id,t,t->par.sparkname));
1761 #endif // PARALLEL_HASKELL
1764 // Check whether the thread that just completed was a main
1765 // thread, and if so return with the result.
1767 // There is an assumption here that all thread completion goes
1768 // through this point; we need to make sure that if a thread
1769 // ends up in the ThreadKilled state, that it stays on the run
1770 // queue so it can be dealt with here.
1773 #if defined(RTS_SUPPORTS_THREADS)
1776 mainThread->tso == t
1780 // We are a bound thread: this must be our thread that just
1782 ASSERT(mainThread->tso == t);
1784 if (t->what_next == ThreadComplete) {
1785 if (mainThread->ret) {
1786 // NOTE: return val is tso->sp[1] (see StgStartup.hc)
1787 *(mainThread->ret) = (StgClosure *)mainThread->tso->sp[1];
1789 mainThread->stat = Success;
1791 if (mainThread->ret) {
1792 *(mainThread->ret) = NULL;
1795 mainThread->stat = Interrupted;
1797 mainThread->stat = Killed;
1801 removeThreadLabel((StgWord)mainThread->tso->id);
1803 if (mainThread->prev == NULL) {
1804 main_threads = mainThread->link;
1806 mainThread->prev->link = mainThread->link;
1808 if (mainThread->link != NULL) {
1809 mainThread->link->prev = NULL;
1811 releaseCapability(cap);
1812 return rtsTrue; // tells schedule() to return
1815 #ifdef RTS_SUPPORTS_THREADS
1816 ASSERT(t->main == NULL);
1818 if (t->main != NULL) {
1819 // Must be a main thread that is not the topmost one. Leave
1820 // it on the run queue until the stack has unwound to the
1821 // point where we can deal with this. Leaving it on the run
1822 // queue also ensures that the garbage collector knows about
1823 // this thread and its return value (it gets dropped from the
1824 // all_threads list so there's no other way to find it).
1825 APPEND_TO_RUN_QUEUE(t);
1831 /* -----------------------------------------------------------------------------
1832 * Perform a heap census, if PROFILING
1833 * -------------------------------------------------------------------------- */
1836 scheduleDoHeapProfile( rtsBool ready_to_gc STG_UNUSED )
1838 #if defined(PROFILING)
1839 // When we have +RTS -i0 and we're heap profiling, do a census at
1840 // every GC. This lets us get repeatable runs for debugging.
1841 if (performHeapProfile ||
1842 (RtsFlags.ProfFlags.profileInterval==0 &&
1843 RtsFlags.ProfFlags.doHeapProfile && ready_to_gc)) {
1844 GarbageCollect(GetRoots, rtsTrue);
1846 performHeapProfile = rtsFalse;
1847 return rtsTrue; // true <=> we already GC'd
1853 /* -----------------------------------------------------------------------------
1854 * Perform a garbage collection if necessary
1855 * ASSUMES: sched_mutex
1856 * -------------------------------------------------------------------------- */
1859 scheduleDoGC( Capability *cap STG_UNUSED )
1863 static rtsBool waiting_for_gc;
1864 int n_capabilities = RtsFlags.ParFlags.nNodes - 1;
1865 // subtract one because we're already holding one.
1866 Capability *caps[n_capabilities];
1870 // In order to GC, there must be no threads running Haskell code.
1871 // Therefore, the GC thread needs to hold *all* the capabilities,
1872 // and release them after the GC has completed.
1874 // This seems to be the simplest way: previous attempts involved
1875 // making all the threads with capabilities give up their
1876 // capabilities and sleep except for the *last* one, which
1877 // actually did the GC. But it's quite hard to arrange for all
1878 // the other tasks to sleep and stay asleep.
1881 // Someone else is already trying to GC
1882 if (waiting_for_gc) return;
1883 waiting_for_gc = rtsTrue;
1885 caps[n_capabilities] = cap;
1886 while (n_capabilities > 0) {
1887 IF_DEBUG(scheduler, sched_belch("ready_to_gc, grabbing all the capabilies (%d left)", n_capabilities));
1888 waitForReturnCapability(&sched_mutex, &cap);
1890 caps[n_capabilities] = cap;
1893 waiting_for_gc = rtsFalse;
1896 /* Kick any transactions which are invalid back to their
1897 * atomically frames. When next scheduled they will try to
1898 * commit, this commit will fail and they will retry.
1900 for (t = all_threads; t != END_TSO_QUEUE; t = t -> link) {
1901 if (t -> what_next != ThreadRelocated && t -> trec != NO_TREC && t -> why_blocked == NotBlocked) {
1902 if (!stmValidateTransaction (t -> trec)) {
1903 IF_DEBUG(stm, sched_belch("trec %p found wasting its time", t));
1905 // strip the stack back to the ATOMICALLY_FRAME, aborting
1906 // the (nested) transaction, and saving the stack of any
1907 // partially-evaluated thunks on the heap.
1908 raiseAsync_(t, NULL, rtsTrue);
1911 ASSERT(get_itbl((StgClosure *)t->sp)->type == ATOMICALLY_FRAME);
1917 // so this happens periodically:
1918 scheduleCheckBlackHoles();
1920 /* everybody back, start the GC.
1921 * Could do it in this thread, or signal a condition var
1922 * to do it in another thread. Either way, we need to
1923 * broadcast on gc_pending_cond afterward.
1925 #if defined(RTS_SUPPORTS_THREADS)
1926 IF_DEBUG(scheduler,sched_belch("doing GC"));
1928 GarbageCollect(GetRoots,rtsFalse);
1932 // release our stash of capabilities.
1934 for (i = 0; i < RtsFlags.ParFlags.nNodes-1; i++) {
1935 releaseCapability(caps[i]);
1941 /* add a ContinueThread event to continue execution of current thread */
1942 new_event(CurrentProc, CurrentProc, CurrentTime[CurrentProc],
1944 t, (StgClosure*)NULL, (rtsSpark*)NULL);
1946 debugBelch("GRAN: eventq and runnableq after Garbage collection:\n\n");
1952 /* ---------------------------------------------------------------------------
1953 * rtsSupportsBoundThreads(): is the RTS built to support bound threads?
1954 * used by Control.Concurrent for error checking.
1955 * ------------------------------------------------------------------------- */
1958 rtsSupportsBoundThreads(void)
1967 /* ---------------------------------------------------------------------------
1968 * isThreadBound(tso): check whether tso is bound to an OS thread.
1969 * ------------------------------------------------------------------------- */
1972 isThreadBound(StgTSO* tso USED_IN_THREADED_RTS)
1975 return (tso->main != NULL);
1980 /* ---------------------------------------------------------------------------
1981 * Singleton fork(). Do not copy any running threads.
1982 * ------------------------------------------------------------------------- */
1984 #ifndef mingw32_HOST_OS
1985 #define FORKPROCESS_PRIMOP_SUPPORTED
1988 #ifdef FORKPROCESS_PRIMOP_SUPPORTED
1990 deleteThreadImmediately(StgTSO *tso);
1993 forkProcess(HsStablePtr *entry
1994 #ifndef FORKPROCESS_PRIMOP_SUPPORTED
1999 #ifdef FORKPROCESS_PRIMOP_SUPPORTED
2005 IF_DEBUG(scheduler,sched_belch("forking!"));
2006 rts_lock(); // This not only acquires sched_mutex, it also
2007 // makes sure that no other threads are running
2011 if (pid) { /* parent */
2013 /* just return the pid */
2017 } else { /* child */
2020 // delete all threads
2021 run_queue_hd = run_queue_tl = END_TSO_QUEUE;
2023 for (t = all_threads; t != END_TSO_QUEUE; t = next) {
2026 // don't allow threads to catch the ThreadKilled exception
2027 deleteThreadImmediately(t);
2030 // wipe the main thread list
2031 while((m = main_threads) != NULL) {
2032 main_threads = m->link;
2033 # ifdef THREADED_RTS
2034 closeCondition(&m->bound_thread_cond);
2039 rc = rts_evalStableIO(entry, NULL); // run the action
2040 rts_checkSchedStatus("forkProcess",rc);
2044 hs_exit(); // clean up and exit
2047 #else /* !FORKPROCESS_PRIMOP_SUPPORTED */
2048 barf("forkProcess#: primop not supported, sorry!\n");
2053 /* ---------------------------------------------------------------------------
2054 * deleteAllThreads(): kill all the live threads.
2056 * This is used when we catch a user interrupt (^C), before performing
2057 * any necessary cleanups and running finalizers.
2059 * Locks: sched_mutex held.
2060 * ------------------------------------------------------------------------- */
2063 deleteAllThreads ( void )
2066 IF_DEBUG(scheduler,sched_belch("deleting all threads"));
2067 for (t = all_threads; t != END_TSO_QUEUE; t = next) {
2068 next = t->global_link;
2072 // The run queue now contains a bunch of ThreadKilled threads. We
2073 // must not throw these away: the main thread(s) will be in there
2074 // somewhere, and the main scheduler loop has to deal with it.
2075 // Also, the run queue is the only thing keeping these threads from
2076 // being GC'd, and we don't want the "main thread has been GC'd" panic.
2078 ASSERT(blocked_queue_hd == END_TSO_QUEUE);
2079 ASSERT(blackhole_queue == END_TSO_QUEUE);
2080 ASSERT(sleeping_queue == END_TSO_QUEUE);
2083 /* startThread and insertThread are now in GranSim.c -- HWL */
2086 /* ---------------------------------------------------------------------------
2087 * Suspending & resuming Haskell threads.
2089 * When making a "safe" call to C (aka _ccall_GC), the task gives back
2090 * its capability before calling the C function. This allows another
2091 * task to pick up the capability and carry on running Haskell
2092 * threads. It also means that if the C call blocks, it won't lock
2095 * The Haskell thread making the C call is put to sleep for the
2096 * duration of the call, on the susepended_ccalling_threads queue. We
2097 * give out a token to the task, which it can use to resume the thread
2098 * on return from the C function.
2099 * ------------------------------------------------------------------------- */
2102 suspendThread( StgRegTable *reg )
2106 int saved_errno = errno;
2108 /* assume that *reg is a pointer to the StgRegTable part
2111 cap = (Capability *)((void *)((unsigned char*)reg - sizeof(StgFunTable)));
2113 ACQUIRE_LOCK(&sched_mutex);
2116 sched_belch("thread %d did a _ccall_gc", cap->r.rCurrentTSO->id));
2118 // XXX this might not be necessary --SDM
2119 cap->r.rCurrentTSO->what_next = ThreadRunGHC;
2121 threadPaused(cap->r.rCurrentTSO);
2122 cap->r.rCurrentTSO->link = suspended_ccalling_threads;
2123 suspended_ccalling_threads = cap->r.rCurrentTSO;
2125 if(cap->r.rCurrentTSO->blocked_exceptions == NULL) {
2126 cap->r.rCurrentTSO->why_blocked = BlockedOnCCall;
2127 cap->r.rCurrentTSO->blocked_exceptions = END_TSO_QUEUE;
2129 cap->r.rCurrentTSO->why_blocked = BlockedOnCCall_NoUnblockExc;
2132 /* Use the thread ID as the token; it should be unique */
2133 tok = cap->r.rCurrentTSO->id;
2135 /* Hand back capability */
2136 cap->r.rInHaskell = rtsFalse;
2137 releaseCapability(cap);
2139 #if defined(RTS_SUPPORTS_THREADS)
2140 /* Preparing to leave the RTS, so ensure there's a native thread/task
2141 waiting to take over.
2143 IF_DEBUG(scheduler, sched_belch("worker (token %d): leaving RTS", tok));
2146 RELEASE_LOCK(&sched_mutex);
2148 errno = saved_errno;
2153 resumeThread( StgInt tok )
2155 StgTSO *tso, **prev;
2157 int saved_errno = errno;
2159 #if defined(RTS_SUPPORTS_THREADS)
2160 /* Wait for permission to re-enter the RTS with the result. */
2161 ACQUIRE_LOCK(&sched_mutex);
2162 waitForReturnCapability(&sched_mutex, &cap);
2164 IF_DEBUG(scheduler, sched_belch("worker (token %d): re-entering RTS", tok));
2166 grabCapability(&cap);
2169 /* Remove the thread off of the suspended list */
2170 prev = &suspended_ccalling_threads;
2171 for (tso = suspended_ccalling_threads;
2172 tso != END_TSO_QUEUE;
2173 prev = &tso->link, tso = tso->link) {
2174 if (tso->id == (StgThreadID)tok) {
2179 if (tso == END_TSO_QUEUE) {
2180 barf("resumeThread: thread not found");
2182 tso->link = END_TSO_QUEUE;
2184 if(tso->why_blocked == BlockedOnCCall) {
2185 awakenBlockedQueueNoLock(tso->blocked_exceptions);
2186 tso->blocked_exceptions = NULL;
2189 /* Reset blocking status */
2190 tso->why_blocked = NotBlocked;
2192 cap->r.rCurrentTSO = tso;
2193 cap->r.rInHaskell = rtsTrue;
2194 RELEASE_LOCK(&sched_mutex);
2195 errno = saved_errno;
2199 /* ---------------------------------------------------------------------------
2200 * Comparing Thread ids.
2202 * This is used from STG land in the implementation of the
2203 * instances of Eq/Ord for ThreadIds.
2204 * ------------------------------------------------------------------------ */
2207 cmp_thread(StgPtr tso1, StgPtr tso2)
2209 StgThreadID id1 = ((StgTSO *)tso1)->id;
2210 StgThreadID id2 = ((StgTSO *)tso2)->id;
2212 if (id1 < id2) return (-1);
2213 if (id1 > id2) return 1;
2217 /* ---------------------------------------------------------------------------
2218 * Fetching the ThreadID from an StgTSO.
2220 * This is used in the implementation of Show for ThreadIds.
2221 * ------------------------------------------------------------------------ */
2223 rts_getThreadId(StgPtr tso)
2225 return ((StgTSO *)tso)->id;
2230 labelThread(StgPtr tso, char *label)
2235 /* Caveat: Once set, you can only set the thread name to "" */
2236 len = strlen(label)+1;
2237 buf = stgMallocBytes(len * sizeof(char), "Schedule.c:labelThread()");
2238 strncpy(buf,label,len);
2239 /* Update will free the old memory for us */
2240 updateThreadLabel(((StgTSO *)tso)->id,buf);
2244 /* ---------------------------------------------------------------------------
2245 Create a new thread.
2247 The new thread starts with the given stack size. Before the
2248 scheduler can run, however, this thread needs to have a closure
2249 (and possibly some arguments) pushed on its stack. See
2250 pushClosure() in Schedule.h.
2252 createGenThread() and createIOThread() (in SchedAPI.h) are
2253 convenient packaged versions of this function.
2255 currently pri (priority) is only used in a GRAN setup -- HWL
2256 ------------------------------------------------------------------------ */
2258 /* currently pri (priority) is only used in a GRAN setup -- HWL */
2260 createThread(nat size, StgInt pri)
2263 createThread(nat size)
2270 /* First check whether we should create a thread at all */
2271 #if defined(PARALLEL_HASKELL)
2272 /* check that no more than RtsFlags.ParFlags.maxThreads threads are created */
2273 if (advisory_thread_count >= RtsFlags.ParFlags.maxThreads) {
2275 debugBelch("{createThread}Daq ghuH: refusing to create another thread; no more than %d threads allowed (currently %d)\n",
2276 RtsFlags.ParFlags.maxThreads, advisory_thread_count);
2277 return END_TSO_QUEUE;
2283 ASSERT(!RtsFlags.GranFlags.Light || CurrentProc==0);
2286 // ToDo: check whether size = stack_size - TSO_STRUCT_SIZEW
2288 /* catch ridiculously small stack sizes */
2289 if (size < MIN_STACK_WORDS + TSO_STRUCT_SIZEW) {
2290 size = MIN_STACK_WORDS + TSO_STRUCT_SIZEW;
2293 stack_size = size - TSO_STRUCT_SIZEW;
2295 tso = (StgTSO *)allocate(size);
2296 TICK_ALLOC_TSO(stack_size, 0);
2298 SET_HDR(tso, &stg_TSO_info, CCS_SYSTEM);
2300 SET_GRAN_HDR(tso, ThisPE);
2303 // Always start with the compiled code evaluator
2304 tso->what_next = ThreadRunGHC;
2306 tso->id = next_thread_id++;
2307 tso->why_blocked = NotBlocked;
2308 tso->blocked_exceptions = NULL;
2310 tso->saved_errno = 0;
2313 tso->stack_size = stack_size;
2314 tso->max_stack_size = round_to_mblocks(RtsFlags.GcFlags.maxStkSize)
2316 tso->sp = (P_)&(tso->stack) + stack_size;
2318 tso->trec = NO_TREC;
2321 tso->prof.CCCS = CCS_MAIN;
2324 /* put a stop frame on the stack */
2325 tso->sp -= sizeofW(StgStopFrame);
2326 SET_HDR((StgClosure*)tso->sp,(StgInfoTable *)&stg_stop_thread_info,CCS_SYSTEM);
2327 tso->link = END_TSO_QUEUE;
2331 /* uses more flexible routine in GranSim */
2332 insertThread(tso, CurrentProc);
2334 /* In a non-GranSim setup the pushing of a TSO onto the runq is separated
2340 if (RtsFlags.GranFlags.GranSimStats.Full)
2341 DumpGranEvent(GR_START,tso);
2342 #elif defined(PARALLEL_HASKELL)
2343 if (RtsFlags.ParFlags.ParStats.Full)
2344 DumpGranEvent(GR_STARTQ,tso);
2345 /* HACk to avoid SCHEDULE
2349 /* Link the new thread on the global thread list.
2351 tso->global_link = all_threads;
2355 tso->dist.priority = MandatoryPriority; //by default that is...
2359 tso->gran.pri = pri;
2361 tso->gran.magic = TSO_MAGIC; // debugging only
2363 tso->gran.sparkname = 0;
2364 tso->gran.startedat = CURRENT_TIME;
2365 tso->gran.exported = 0;
2366 tso->gran.basicblocks = 0;
2367 tso->gran.allocs = 0;
2368 tso->gran.exectime = 0;
2369 tso->gran.fetchtime = 0;
2370 tso->gran.fetchcount = 0;
2371 tso->gran.blocktime = 0;
2372 tso->gran.blockcount = 0;
2373 tso->gran.blockedat = 0;
2374 tso->gran.globalsparks = 0;
2375 tso->gran.localsparks = 0;
2376 if (RtsFlags.GranFlags.Light)
2377 tso->gran.clock = Now; /* local clock */
2379 tso->gran.clock = 0;
2381 IF_DEBUG(gran,printTSO(tso));
2382 #elif defined(PARALLEL_HASKELL)
2384 tso->par.magic = TSO_MAGIC; // debugging only
2386 tso->par.sparkname = 0;
2387 tso->par.startedat = CURRENT_TIME;
2388 tso->par.exported = 0;
2389 tso->par.basicblocks = 0;
2390 tso->par.allocs = 0;
2391 tso->par.exectime = 0;
2392 tso->par.fetchtime = 0;
2393 tso->par.fetchcount = 0;
2394 tso->par.blocktime = 0;
2395 tso->par.blockcount = 0;
2396 tso->par.blockedat = 0;
2397 tso->par.globalsparks = 0;
2398 tso->par.localsparks = 0;
2402 globalGranStats.tot_threads_created++;
2403 globalGranStats.threads_created_on_PE[CurrentProc]++;
2404 globalGranStats.tot_sq_len += spark_queue_len(CurrentProc);
2405 globalGranStats.tot_sq_probes++;
2406 #elif defined(PARALLEL_HASKELL)
2407 // collect parallel global statistics (currently done together with GC stats)
2408 if (RtsFlags.ParFlags.ParStats.Global &&
2409 RtsFlags.GcFlags.giveStats > NO_GC_STATS) {
2410 //debugBelch("Creating thread %d @ %11.2f\n", tso->id, usertime());
2411 globalParStats.tot_threads_created++;
2417 sched_belch("==__ schedule: Created TSO %d (%p);",
2418 CurrentProc, tso, tso->id));
2419 #elif defined(PARALLEL_HASKELL)
2420 IF_PAR_DEBUG(verbose,
2421 sched_belch("==__ schedule: Created TSO %d (%p); %d threads active",
2422 (long)tso->id, tso, advisory_thread_count));
2424 IF_DEBUG(scheduler,sched_belch("created thread %ld, stack size = %lx words",
2425 (long)tso->id, (long)tso->stack_size));
2432 all parallel thread creation calls should fall through the following routine.
2435 createThreadFromSpark(rtsSpark spark)
2437 ASSERT(spark != (rtsSpark)NULL);
2438 // JB: TAKE CARE OF THIS COUNTER! BUGGY
2439 if (advisory_thread_count >= RtsFlags.ParFlags.maxThreads)
2441 barf("{createSparkThread}Daq ghuH: refusing to create another thread; no more than %d threads allowed (currently %d)",
2442 RtsFlags.ParFlags.maxThreads, advisory_thread_count);
2443 return END_TSO_QUEUE;
2447 tso = createThread(RtsFlags.GcFlags.initialStkSize);
2448 if (tso==END_TSO_QUEUE)
2449 barf("createSparkThread: Cannot create TSO");
2451 tso->priority = AdvisoryPriority;
2453 pushClosure(tso,spark);
2455 advisory_thread_count++; // JB: TAKE CARE OF THIS COUNTER! BUGGY
2462 Turn a spark into a thread.
2463 ToDo: fix for SMP (needs to acquire SCHED_MUTEX!)
2467 activateSpark (rtsSpark spark)
2471 tso = createSparkThread(spark);
2472 if (RtsFlags.ParFlags.ParStats.Full) {
2473 //ASSERT(run_queue_hd == END_TSO_QUEUE); // I think ...
2474 IF_PAR_DEBUG(verbose,
2475 debugBelch("==^^ activateSpark: turning spark of closure %p (%s) into a thread\n",
2476 (StgClosure *)spark, info_type((StgClosure *)spark)));
2478 // ToDo: fwd info on local/global spark to thread -- HWL
2479 // tso->gran.exported = spark->exported;
2480 // tso->gran.locked = !spark->global;
2481 // tso->gran.sparkname = spark->name;
2487 /* ---------------------------------------------------------------------------
2490 * scheduleThread puts a thread on the head of the runnable queue.
2491 * This will usually be done immediately after a thread is created.
2492 * The caller of scheduleThread must create the thread using e.g.
2493 * createThread and push an appropriate closure
2494 * on this thread's stack before the scheduler is invoked.
2495 * ------------------------------------------------------------------------ */
2498 scheduleThread_(StgTSO *tso)
2500 // The thread goes at the *end* of the run-queue, to avoid possible
2501 // starvation of any threads already on the queue.
2502 APPEND_TO_RUN_QUEUE(tso);
2507 scheduleThread(StgTSO* tso)
2509 ACQUIRE_LOCK(&sched_mutex);
2510 scheduleThread_(tso);
2511 RELEASE_LOCK(&sched_mutex);
2514 #if defined(RTS_SUPPORTS_THREADS)
2515 static Condition bound_cond_cache;
2516 static int bound_cond_cache_full = 0;
2521 scheduleWaitThread(StgTSO* tso, /*[out]*/HaskellObj* ret,
2522 Capability *initialCapability)
2524 // Precondition: sched_mutex must be held
2527 m = stgMallocBytes(sizeof(StgMainThread), "waitThread");
2532 m->link = main_threads;
2534 if (main_threads != NULL) {
2535 main_threads->prev = m;
2539 #if defined(RTS_SUPPORTS_THREADS)
2540 // Allocating a new condition for each thread is expensive, so we
2541 // cache one. This is a pretty feeble hack, but it helps speed up
2542 // consecutive call-ins quite a bit.
2543 if (bound_cond_cache_full) {
2544 m->bound_thread_cond = bound_cond_cache;
2545 bound_cond_cache_full = 0;
2547 initCondition(&m->bound_thread_cond);
2551 /* Put the thread on the main-threads list prior to scheduling the TSO.
2552 Failure to do so introduces a race condition in the MT case (as
2553 identified by Wolfgang Thaller), whereby the new task/OS thread
2554 created by scheduleThread_() would complete prior to the thread
2555 that spawned it managed to put 'itself' on the main-threads list.
2556 The upshot of it all being that the worker thread wouldn't get to
2557 signal the completion of the its work item for the main thread to
2558 see (==> it got stuck waiting.) -- sof 6/02.
2560 IF_DEBUG(scheduler, sched_belch("waiting for thread (%d)", tso->id));
2562 APPEND_TO_RUN_QUEUE(tso);
2563 // NB. Don't call threadRunnable() here, because the thread is
2564 // bound and only runnable by *this* OS thread, so waking up other
2565 // workers will just slow things down.
2567 return waitThread_(m, initialCapability);
2570 /* ---------------------------------------------------------------------------
2573 * Initialise the scheduler. This resets all the queues - if the
2574 * queues contained any threads, they'll be garbage collected at the
2577 * ------------------------------------------------------------------------ */
2585 for (i=0; i<=MAX_PROC; i++) {
2586 run_queue_hds[i] = END_TSO_QUEUE;
2587 run_queue_tls[i] = END_TSO_QUEUE;
2588 blocked_queue_hds[i] = END_TSO_QUEUE;
2589 blocked_queue_tls[i] = END_TSO_QUEUE;
2590 ccalling_threadss[i] = END_TSO_QUEUE;
2591 blackhole_queue[i] = END_TSO_QUEUE;
2592 sleeping_queue = END_TSO_QUEUE;
2595 run_queue_hd = END_TSO_QUEUE;
2596 run_queue_tl = END_TSO_QUEUE;
2597 blocked_queue_hd = END_TSO_QUEUE;
2598 blocked_queue_tl = END_TSO_QUEUE;
2599 blackhole_queue = END_TSO_QUEUE;
2600 sleeping_queue = END_TSO_QUEUE;
2603 suspended_ccalling_threads = END_TSO_QUEUE;
2605 main_threads = NULL;
2606 all_threads = END_TSO_QUEUE;
2611 RtsFlags.ConcFlags.ctxtSwitchTicks =
2612 RtsFlags.ConcFlags.ctxtSwitchTime / TICK_MILLISECS;
2614 #if defined(RTS_SUPPORTS_THREADS)
2615 /* Initialise the mutex and condition variables used by
2617 initMutex(&sched_mutex);
2618 initMutex(&term_mutex);
2621 ACQUIRE_LOCK(&sched_mutex);
2623 /* A capability holds the state a native thread needs in
2624 * order to execute STG code. At least one capability is
2625 * floating around (only SMP builds have more than one).
2629 #if defined(RTS_SUPPORTS_THREADS)
2634 /* eagerly start some extra workers */
2635 startingWorkerThread = RtsFlags.ParFlags.nNodes;
2636 startTasks(RtsFlags.ParFlags.nNodes, taskStart);
2639 #if /* defined(SMP) ||*/ defined(PARALLEL_HASKELL)
2643 RELEASE_LOCK(&sched_mutex);
2647 exitScheduler( void )
2649 interrupted = rtsTrue;
2650 shutting_down_scheduler = rtsTrue;
2651 #if defined(RTS_SUPPORTS_THREADS)
2652 if (threadIsTask(osThreadId())) { taskStop(); }
2657 /* ----------------------------------------------------------------------------
2658 Managing the per-task allocation areas.
2660 Each capability comes with an allocation area. These are
2661 fixed-length block lists into which allocation can be done.
2663 ToDo: no support for two-space collection at the moment???
2664 ------------------------------------------------------------------------- */
2666 static SchedulerStatus
2667 waitThread_(StgMainThread* m, Capability *initialCapability)
2669 SchedulerStatus stat;
2671 // Precondition: sched_mutex must be held.
2672 IF_DEBUG(scheduler, sched_belch("new main thread (%d)", m->tso->id));
2675 /* GranSim specific init */
2676 CurrentTSO = m->tso; // the TSO to run
2677 procStatus[MainProc] = Busy; // status of main PE
2678 CurrentProc = MainProc; // PE to run it on
2679 schedule(m,initialCapability);
2681 schedule(m,initialCapability);
2682 ASSERT(m->stat != NoStatus);
2687 #if defined(RTS_SUPPORTS_THREADS)
2688 // Free the condition variable, returning it to the cache if possible.
2689 if (!bound_cond_cache_full) {
2690 bound_cond_cache = m->bound_thread_cond;
2691 bound_cond_cache_full = 1;
2693 closeCondition(&m->bound_thread_cond);
2697 IF_DEBUG(scheduler, sched_belch("main thread (%d) finished", m->tso->id));
2700 // Postcondition: sched_mutex still held
2704 /* ---------------------------------------------------------------------------
2705 Where are the roots that we know about?
2707 - all the threads on the runnable queue
2708 - all the threads on the blocked queue
2709 - all the threads on the sleeping queue
2710 - all the thread currently executing a _ccall_GC
2711 - all the "main threads"
2713 ------------------------------------------------------------------------ */
2715 /* This has to be protected either by the scheduler monitor, or by the
2716 garbage collection monitor (probably the latter).
2721 GetRoots( evac_fn evac )
2726 for (i=0; i<=RtsFlags.GranFlags.proc; i++) {
2727 if ((run_queue_hds[i] != END_TSO_QUEUE) && ((run_queue_hds[i] != NULL)))
2728 evac((StgClosure **)&run_queue_hds[i]);
2729 if ((run_queue_tls[i] != END_TSO_QUEUE) && ((run_queue_tls[i] != NULL)))
2730 evac((StgClosure **)&run_queue_tls[i]);
2732 if ((blocked_queue_hds[i] != END_TSO_QUEUE) && ((blocked_queue_hds[i] != NULL)))
2733 evac((StgClosure **)&blocked_queue_hds[i]);
2734 if ((blocked_queue_tls[i] != END_TSO_QUEUE) && ((blocked_queue_tls[i] != NULL)))
2735 evac((StgClosure **)&blocked_queue_tls[i]);
2736 if ((ccalling_threadss[i] != END_TSO_QUEUE) && ((ccalling_threadss[i] != NULL)))
2737 evac((StgClosure **)&ccalling_threads[i]);
2744 if (run_queue_hd != END_TSO_QUEUE) {
2745 ASSERT(run_queue_tl != END_TSO_QUEUE);
2746 evac((StgClosure **)&run_queue_hd);
2747 evac((StgClosure **)&run_queue_tl);
2750 if (blocked_queue_hd != END_TSO_QUEUE) {
2751 ASSERT(blocked_queue_tl != END_TSO_QUEUE);
2752 evac((StgClosure **)&blocked_queue_hd);
2753 evac((StgClosure **)&blocked_queue_tl);
2756 if (sleeping_queue != END_TSO_QUEUE) {
2757 evac((StgClosure **)&sleeping_queue);
2761 if (blackhole_queue != END_TSO_QUEUE) {
2762 evac((StgClosure **)&blackhole_queue);
2765 if (suspended_ccalling_threads != END_TSO_QUEUE) {
2766 evac((StgClosure **)&suspended_ccalling_threads);
2769 #if defined(PARALLEL_HASKELL) || defined(GRAN)
2770 markSparkQueue(evac);
2773 #if defined(RTS_USER_SIGNALS)
2774 // mark the signal handlers (signals should be already blocked)
2775 markSignalHandlers(evac);
2779 /* -----------------------------------------------------------------------------
2782 This is the interface to the garbage collector from Haskell land.
2783 We provide this so that external C code can allocate and garbage
2784 collect when called from Haskell via _ccall_GC.
2786 It might be useful to provide an interface whereby the programmer
2787 can specify more roots (ToDo).
2789 This needs to be protected by the GC condition variable above. KH.
2790 -------------------------------------------------------------------------- */
2792 static void (*extra_roots)(evac_fn);
2797 /* Obligated to hold this lock upon entry */
2798 ACQUIRE_LOCK(&sched_mutex);
2799 GarbageCollect(GetRoots,rtsFalse);
2800 RELEASE_LOCK(&sched_mutex);
2804 performMajorGC(void)
2806 ACQUIRE_LOCK(&sched_mutex);
2807 GarbageCollect(GetRoots,rtsTrue);
2808 RELEASE_LOCK(&sched_mutex);
2812 AllRoots(evac_fn evac)
2814 GetRoots(evac); // the scheduler's roots
2815 extra_roots(evac); // the user's roots
2819 performGCWithRoots(void (*get_roots)(evac_fn))
2821 ACQUIRE_LOCK(&sched_mutex);
2822 extra_roots = get_roots;
2823 GarbageCollect(AllRoots,rtsFalse);
2824 RELEASE_LOCK(&sched_mutex);
2827 /* -----------------------------------------------------------------------------
2830 If the thread has reached its maximum stack size, then raise the
2831 StackOverflow exception in the offending thread. Otherwise
2832 relocate the TSO into a larger chunk of memory and adjust its stack
2834 -------------------------------------------------------------------------- */
2837 threadStackOverflow(StgTSO *tso)
2839 nat new_stack_size, stack_words;
2844 IF_DEBUG(sanity,checkTSO(tso));
2845 if (tso->stack_size >= tso->max_stack_size) {
2848 debugBelch("@@ threadStackOverflow of TSO %ld (%p): stack too large (now %ld; max is %ld)\n",
2849 (long)tso->id, tso, (long)tso->stack_size, (long)tso->max_stack_size);
2850 /* If we're debugging, just print out the top of the stack */
2851 printStackChunk(tso->sp, stg_min(tso->stack+tso->stack_size,
2854 /* Send this thread the StackOverflow exception */
2855 raiseAsync(tso, (StgClosure *)stackOverflow_closure);
2859 /* Try to double the current stack size. If that takes us over the
2860 * maximum stack size for this thread, then use the maximum instead.
2861 * Finally round up so the TSO ends up as a whole number of blocks.
2863 new_stack_size = stg_min(tso->stack_size * 2, tso->max_stack_size);
2864 new_tso_size = (lnat)BLOCK_ROUND_UP(new_stack_size * sizeof(W_) +
2865 TSO_STRUCT_SIZE)/sizeof(W_);
2866 new_tso_size = round_to_mblocks(new_tso_size); /* Be MBLOCK-friendly */
2867 new_stack_size = new_tso_size - TSO_STRUCT_SIZEW;
2869 IF_DEBUG(scheduler, debugBelch("== sched: increasing stack size from %d words to %d.\n", tso->stack_size, new_stack_size));
2871 dest = (StgTSO *)allocate(new_tso_size);
2872 TICK_ALLOC_TSO(new_stack_size,0);
2874 /* copy the TSO block and the old stack into the new area */
2875 memcpy(dest,tso,TSO_STRUCT_SIZE);
2876 stack_words = tso->stack + tso->stack_size - tso->sp;
2877 new_sp = (P_)dest + new_tso_size - stack_words;
2878 memcpy(new_sp, tso->sp, stack_words * sizeof(W_));
2880 /* relocate the stack pointers... */
2882 dest->stack_size = new_stack_size;
2884 /* Mark the old TSO as relocated. We have to check for relocated
2885 * TSOs in the garbage collector and any primops that deal with TSOs.
2887 * It's important to set the sp value to just beyond the end
2888 * of the stack, so we don't attempt to scavenge any part of the
2891 tso->what_next = ThreadRelocated;
2893 tso->sp = (P_)&(tso->stack[tso->stack_size]);
2894 tso->why_blocked = NotBlocked;
2896 IF_PAR_DEBUG(verbose,
2897 debugBelch("@@ threadStackOverflow of TSO %d (now at %p): stack size increased to %ld\n",
2898 tso->id, tso, tso->stack_size);
2899 /* If we're debugging, just print out the top of the stack */
2900 printStackChunk(tso->sp, stg_min(tso->stack+tso->stack_size,
2903 IF_DEBUG(sanity,checkTSO(tso));
2905 IF_DEBUG(scheduler,printTSO(dest));
2911 /* ---------------------------------------------------------------------------
2912 Wake up a queue that was blocked on some resource.
2913 ------------------------------------------------------------------------ */
2917 unblockCount ( StgBlockingQueueElement *bqe, StgClosure *node )
2920 #elif defined(PARALLEL_HASKELL)
2922 unblockCount ( StgBlockingQueueElement *bqe, StgClosure *node )
2924 /* write RESUME events to log file and
2925 update blocked and fetch time (depending on type of the orig closure) */
2926 if (RtsFlags.ParFlags.ParStats.Full) {
2927 DumpRawGranEvent(CURRENT_PROC, CURRENT_PROC,
2928 GR_RESUMEQ, ((StgTSO *)bqe), ((StgTSO *)bqe)->block_info.closure,
2929 0, 0 /* spark_queue_len(ADVISORY_POOL) */);
2930 if (EMPTY_RUN_QUEUE())
2931 emitSchedule = rtsTrue;
2933 switch (get_itbl(node)->type) {
2935 ((StgTSO *)bqe)->par.fetchtime += CURRENT_TIME-((StgTSO *)bqe)->par.blockedat;
2940 ((StgTSO *)bqe)->par.blocktime += CURRENT_TIME-((StgTSO *)bqe)->par.blockedat;
2947 barf("{unblockOneLocked}Daq Qagh: unexpected closure in blocking queue");
2954 static StgBlockingQueueElement *
2955 unblockOneLocked(StgBlockingQueueElement *bqe, StgClosure *node)
2958 PEs node_loc, tso_loc;
2960 node_loc = where_is(node); // should be lifted out of loop
2961 tso = (StgTSO *)bqe; // wastes an assignment to get the type right
2962 tso_loc = where_is((StgClosure *)tso);
2963 if (IS_LOCAL_TO(PROCS(node),tso_loc)) { // TSO is local
2964 /* !fake_fetch => TSO is on CurrentProc is same as IS_LOCAL_TO */
2965 ASSERT(CurrentProc!=node_loc || tso_loc==CurrentProc);
2966 CurrentTime[CurrentProc] += RtsFlags.GranFlags.Costs.lunblocktime;
2967 // insertThread(tso, node_loc);
2968 new_event(tso_loc, tso_loc, CurrentTime[CurrentProc],
2970 tso, node, (rtsSpark*)NULL);
2971 tso->link = END_TSO_QUEUE; // overwrite link just to be sure
2974 } else { // TSO is remote (actually should be FMBQ)
2975 CurrentTime[CurrentProc] += RtsFlags.GranFlags.Costs.mpacktime +
2976 RtsFlags.GranFlags.Costs.gunblocktime +
2977 RtsFlags.GranFlags.Costs.latency;
2978 new_event(tso_loc, CurrentProc, CurrentTime[CurrentProc],
2980 tso, node, (rtsSpark*)NULL);
2981 tso->link = END_TSO_QUEUE; // overwrite link just to be sure
2984 /* the thread-queue-overhead is accounted for in either Resume or UnblockThread */
2986 debugBelch(" %s TSO %d (%p) [PE %d] (block_info.closure=%p) (next=%p) ,",
2987 (node_loc==tso_loc ? "Local" : "Global"),
2988 tso->id, tso, CurrentProc, tso->block_info.closure, tso->link));
2989 tso->block_info.closure = NULL;
2990 IF_DEBUG(scheduler,debugBelch("-- Waking up thread %ld (%p)\n",
2993 #elif defined(PARALLEL_HASKELL)
2994 static StgBlockingQueueElement *
2995 unblockOneLocked(StgBlockingQueueElement *bqe, StgClosure *node)
2997 StgBlockingQueueElement *next;
2999 switch (get_itbl(bqe)->type) {
3001 ASSERT(((StgTSO *)bqe)->why_blocked != NotBlocked);
3002 /* if it's a TSO just push it onto the run_queue */
3004 ((StgTSO *)bqe)->link = END_TSO_QUEUE; // debugging?
3005 APPEND_TO_RUN_QUEUE((StgTSO *)bqe);
3007 unblockCount(bqe, node);
3008 /* reset blocking status after dumping event */
3009 ((StgTSO *)bqe)->why_blocked = NotBlocked;
3013 /* if it's a BLOCKED_FETCH put it on the PendingFetches list */
3015 bqe->link = (StgBlockingQueueElement *)PendingFetches;
3016 PendingFetches = (StgBlockedFetch *)bqe;
3020 /* can ignore this case in a non-debugging setup;
3021 see comments on RBHSave closures above */
3023 /* check that the closure is an RBHSave closure */
3024 ASSERT(get_itbl((StgClosure *)bqe) == &stg_RBH_Save_0_info ||
3025 get_itbl((StgClosure *)bqe) == &stg_RBH_Save_1_info ||
3026 get_itbl((StgClosure *)bqe) == &stg_RBH_Save_2_info);
3030 barf("{unblockOneLocked}Daq Qagh: Unexpected IP (%#lx; %s) in blocking queue at %#lx\n",
3031 get_itbl((StgClosure *)bqe), info_type((StgClosure *)bqe),
3035 IF_PAR_DEBUG(bq, debugBelch(", %p (%s)\n", bqe, info_type((StgClosure*)bqe)));
3039 #else /* !GRAN && !PARALLEL_HASKELL */
3041 unblockOneLocked(StgTSO *tso)
3045 ASSERT(get_itbl(tso)->type == TSO);
3046 ASSERT(tso->why_blocked != NotBlocked);
3047 tso->why_blocked = NotBlocked;
3049 tso->link = END_TSO_QUEUE;
3050 APPEND_TO_RUN_QUEUE(tso);
3052 IF_DEBUG(scheduler,sched_belch("waking up thread %ld", (long)tso->id));
3057 #if defined(GRAN) || defined(PARALLEL_HASKELL)
3058 INLINE_ME StgBlockingQueueElement *
3059 unblockOne(StgBlockingQueueElement *bqe, StgClosure *node)
3061 ACQUIRE_LOCK(&sched_mutex);
3062 bqe = unblockOneLocked(bqe, node);
3063 RELEASE_LOCK(&sched_mutex);
3068 unblockOne(StgTSO *tso)
3070 ACQUIRE_LOCK(&sched_mutex);
3071 tso = unblockOneLocked(tso);
3072 RELEASE_LOCK(&sched_mutex);
3079 awakenBlockedQueue(StgBlockingQueueElement *q, StgClosure *node)
3081 StgBlockingQueueElement *bqe;
3086 debugBelch("##-_ AwBQ for node %p on PE %d @ %ld by TSO %d (%p): \n", \
3087 node, CurrentProc, CurrentTime[CurrentProc],
3088 CurrentTSO->id, CurrentTSO));
3090 node_loc = where_is(node);
3092 ASSERT(q == END_BQ_QUEUE ||
3093 get_itbl(q)->type == TSO || // q is either a TSO or an RBHSave
3094 get_itbl(q)->type == CONSTR); // closure (type constructor)
3095 ASSERT(is_unique(node));
3097 /* FAKE FETCH: magically copy the node to the tso's proc;
3098 no Fetch necessary because in reality the node should not have been
3099 moved to the other PE in the first place
3101 if (CurrentProc!=node_loc) {
3103 debugBelch("## node %p is on PE %d but CurrentProc is %d (TSO %d); assuming fake fetch and adjusting bitmask (old: %#x)\n",
3104 node, node_loc, CurrentProc, CurrentTSO->id,
3105 // CurrentTSO, where_is(CurrentTSO),
3106 node->header.gran.procs));
3107 node->header.gran.procs = (node->header.gran.procs) | PE_NUMBER(CurrentProc);
3109 debugBelch("## new bitmask of node %p is %#x\n",
3110 node, node->header.gran.procs));
3111 if (RtsFlags.GranFlags.GranSimStats.Global) {
3112 globalGranStats.tot_fake_fetches++;
3117 // ToDo: check: ASSERT(CurrentProc==node_loc);
3118 while (get_itbl(bqe)->type==TSO) { // q != END_TSO_QUEUE) {
3121 bqe points to the current element in the queue
3122 next points to the next element in the queue
3124 //tso = (StgTSO *)bqe; // wastes an assignment to get the type right
3125 //tso_loc = where_is(tso);
3127 bqe = unblockOneLocked(bqe, node);
3130 /* if this is the BQ of an RBH, we have to put back the info ripped out of
3131 the closure to make room for the anchor of the BQ */
3132 if (bqe!=END_BQ_QUEUE) {
3133 ASSERT(get_itbl(node)->type == RBH && get_itbl(bqe)->type == CONSTR);
3135 ASSERT((info_ptr==&RBH_Save_0_info) ||
3136 (info_ptr==&RBH_Save_1_info) ||
3137 (info_ptr==&RBH_Save_2_info));
3139 /* cf. convertToRBH in RBH.c for writing the RBHSave closure */
3140 ((StgRBH *)node)->blocking_queue = (StgBlockingQueueElement *)((StgRBHSave *)bqe)->payload[0];
3141 ((StgRBH *)node)->mut_link = (StgMutClosure *)((StgRBHSave *)bqe)->payload[1];
3144 debugBelch("## Filled in RBH_Save for %p (%s) at end of AwBQ\n",
3145 node, info_type(node)));
3148 /* statistics gathering */
3149 if (RtsFlags.GranFlags.GranSimStats.Global) {
3150 // globalGranStats.tot_bq_processing_time += bq_processing_time;
3151 globalGranStats.tot_bq_len += len; // total length of all bqs awakened
3152 // globalGranStats.tot_bq_len_local += len_local; // same for local TSOs only
3153 globalGranStats.tot_awbq++; // total no. of bqs awakened
3156 debugBelch("## BQ Stats of %p: [%d entries] %s\n",
3157 node, len, (bqe!=END_BQ_QUEUE) ? "RBH" : ""));
3159 #elif defined(PARALLEL_HASKELL)
3161 awakenBlockedQueue(StgBlockingQueueElement *q, StgClosure *node)
3163 StgBlockingQueueElement *bqe;
3165 ACQUIRE_LOCK(&sched_mutex);
3167 IF_PAR_DEBUG(verbose,
3168 debugBelch("##-_ AwBQ for node %p on [%x]: \n",
3172 if(get_itbl(q)->type == CONSTR || q==END_BQ_QUEUE) {
3173 IF_PAR_DEBUG(verbose, debugBelch("## ... nothing to unblock so lets just return. RFP (BUG?)\n"));
3178 ASSERT(q == END_BQ_QUEUE ||
3179 get_itbl(q)->type == TSO ||
3180 get_itbl(q)->type == BLOCKED_FETCH ||
3181 get_itbl(q)->type == CONSTR);
3184 while (get_itbl(bqe)->type==TSO ||
3185 get_itbl(bqe)->type==BLOCKED_FETCH) {
3186 bqe = unblockOneLocked(bqe, node);
3188 RELEASE_LOCK(&sched_mutex);
3191 #else /* !GRAN && !PARALLEL_HASKELL */
3194 awakenBlockedQueueNoLock(StgTSO *tso)
3196 while (tso != END_TSO_QUEUE) {
3197 tso = unblockOneLocked(tso);
3202 awakenBlockedQueue(StgTSO *tso)
3204 ACQUIRE_LOCK(&sched_mutex);
3205 while (tso != END_TSO_QUEUE) {
3206 tso = unblockOneLocked(tso);
3208 RELEASE_LOCK(&sched_mutex);
3212 /* ---------------------------------------------------------------------------
3214 - usually called inside a signal handler so it mustn't do anything fancy.
3215 ------------------------------------------------------------------------ */
3218 interruptStgRts(void)
3224 /* -----------------------------------------------------------------------------
3227 This is for use when we raise an exception in another thread, which
3229 This has nothing to do with the UnblockThread event in GranSim. -- HWL
3230 -------------------------------------------------------------------------- */
3232 #if defined(GRAN) || defined(PARALLEL_HASKELL)
3234 NB: only the type of the blocking queue is different in GranSim and GUM
3235 the operations on the queue-elements are the same
3236 long live polymorphism!
3238 Locks: sched_mutex is held upon entry and exit.
3242 unblockThread(StgTSO *tso)
3244 StgBlockingQueueElement *t, **last;
3246 switch (tso->why_blocked) {
3249 return; /* not blocked */
3252 // Be careful: nothing to do here! We tell the scheduler that the thread
3253 // is runnable and we leave it to the stack-walking code to abort the
3254 // transaction while unwinding the stack. We should perhaps have a debugging
3255 // test to make sure that this really happens and that the 'zombie' transaction
3256 // does not get committed.
3260 ASSERT(get_itbl(tso->block_info.closure)->type == MVAR);
3262 StgBlockingQueueElement *last_tso = END_BQ_QUEUE;
3263 StgMVar *mvar = (StgMVar *)(tso->block_info.closure);
3265 last = (StgBlockingQueueElement **)&mvar->head;
3266 for (t = (StgBlockingQueueElement *)mvar->head;
3268 last = &t->link, last_tso = t, t = t->link) {
3269 if (t == (StgBlockingQueueElement *)tso) {
3270 *last = (StgBlockingQueueElement *)tso->link;
3271 if (mvar->tail == tso) {
3272 mvar->tail = (StgTSO *)last_tso;
3277 barf("unblockThread (MVAR): TSO not found");
3280 case BlockedOnBlackHole:
3281 ASSERT(get_itbl(tso->block_info.closure)->type == BLACKHOLE_BQ);
3283 StgBlockingQueue *bq = (StgBlockingQueue *)(tso->block_info.closure);
3285 last = &bq->blocking_queue;
3286 for (t = bq->blocking_queue;
3288 last = &t->link, t = t->link) {
3289 if (t == (StgBlockingQueueElement *)tso) {
3290 *last = (StgBlockingQueueElement *)tso->link;
3294 barf("unblockThread (BLACKHOLE): TSO not found");
3297 case BlockedOnException:
3299 StgTSO *target = tso->block_info.tso;
3301 ASSERT(get_itbl(target)->type == TSO);
3303 if (target->what_next == ThreadRelocated) {
3304 target = target->link;
3305 ASSERT(get_itbl(target)->type == TSO);
3308 ASSERT(target->blocked_exceptions != NULL);
3310 last = (StgBlockingQueueElement **)&target->blocked_exceptions;
3311 for (t = (StgBlockingQueueElement *)target->blocked_exceptions;
3313 last = &t->link, t = t->link) {
3314 ASSERT(get_itbl(t)->type == TSO);
3315 if (t == (StgBlockingQueueElement *)tso) {
3316 *last = (StgBlockingQueueElement *)tso->link;
3320 barf("unblockThread (Exception): TSO not found");
3324 case BlockedOnWrite:
3325 #if defined(mingw32_HOST_OS)
3326 case BlockedOnDoProc:
3329 /* take TSO off blocked_queue */
3330 StgBlockingQueueElement *prev = NULL;
3331 for (t = (StgBlockingQueueElement *)blocked_queue_hd; t != END_BQ_QUEUE;
3332 prev = t, t = t->link) {
3333 if (t == (StgBlockingQueueElement *)tso) {
3335 blocked_queue_hd = (StgTSO *)t->link;
3336 if ((StgBlockingQueueElement *)blocked_queue_tl == t) {
3337 blocked_queue_tl = END_TSO_QUEUE;
3340 prev->link = t->link;
3341 if ((StgBlockingQueueElement *)blocked_queue_tl == t) {
3342 blocked_queue_tl = (StgTSO *)prev;
3348 barf("unblockThread (I/O): TSO not found");
3351 case BlockedOnDelay:
3353 /* take TSO off sleeping_queue */
3354 StgBlockingQueueElement *prev = NULL;
3355 for (t = (StgBlockingQueueElement *)sleeping_queue; t != END_BQ_QUEUE;
3356 prev = t, t = t->link) {
3357 if (t == (StgBlockingQueueElement *)tso) {
3359 sleeping_queue = (StgTSO *)t->link;
3361 prev->link = t->link;
3366 barf("unblockThread (delay): TSO not found");
3370 barf("unblockThread");
3374 tso->link = END_TSO_QUEUE;
3375 tso->why_blocked = NotBlocked;
3376 tso->block_info.closure = NULL;
3377 PUSH_ON_RUN_QUEUE(tso);
3381 unblockThread(StgTSO *tso)
3385 /* To avoid locking unnecessarily. */
3386 if (tso->why_blocked == NotBlocked) {
3390 switch (tso->why_blocked) {
3393 // Be careful: nothing to do here! We tell the scheduler that the thread
3394 // is runnable and we leave it to the stack-walking code to abort the
3395 // transaction while unwinding the stack. We should perhaps have a debugging
3396 // test to make sure that this really happens and that the 'zombie' transaction
3397 // does not get committed.
3401 ASSERT(get_itbl(tso->block_info.closure)->type == MVAR);
3403 StgTSO *last_tso = END_TSO_QUEUE;
3404 StgMVar *mvar = (StgMVar *)(tso->block_info.closure);
3407 for (t = mvar->head; t != END_TSO_QUEUE;
3408 last = &t->link, last_tso = t, t = t->link) {
3411 if (mvar->tail == tso) {
3412 mvar->tail = last_tso;
3417 barf("unblockThread (MVAR): TSO not found");
3420 case BlockedOnBlackHole:
3422 last = &blackhole_queue;
3423 for (t = blackhole_queue; t != END_TSO_QUEUE;
3424 last = &t->link, t = t->link) {
3430 barf("unblockThread (BLACKHOLE): TSO not found");
3433 case BlockedOnException:
3435 StgTSO *target = tso->block_info.tso;
3437 ASSERT(get_itbl(target)->type == TSO);
3439 while (target->what_next == ThreadRelocated) {
3440 target = target->link;
3441 ASSERT(get_itbl(target)->type == TSO);
3444 ASSERT(target->blocked_exceptions != NULL);
3446 last = &target->blocked_exceptions;
3447 for (t = target->blocked_exceptions; t != END_TSO_QUEUE;
3448 last = &t->link, t = t->link) {
3449 ASSERT(get_itbl(t)->type == TSO);
3455 barf("unblockThread (Exception): TSO not found");
3459 case BlockedOnWrite:
3460 #if defined(mingw32_HOST_OS)
3461 case BlockedOnDoProc:
3464 StgTSO *prev = NULL;
3465 for (t = blocked_queue_hd; t != END_TSO_QUEUE;
3466 prev = t, t = t->link) {
3469 blocked_queue_hd = t->link;
3470 if (blocked_queue_tl == t) {
3471 blocked_queue_tl = END_TSO_QUEUE;
3474 prev->link = t->link;
3475 if (blocked_queue_tl == t) {
3476 blocked_queue_tl = prev;
3482 barf("unblockThread (I/O): TSO not found");
3485 case BlockedOnDelay:
3487 StgTSO *prev = NULL;
3488 for (t = sleeping_queue; t != END_TSO_QUEUE;
3489 prev = t, t = t->link) {
3492 sleeping_queue = t->link;
3494 prev->link = t->link;
3499 barf("unblockThread (delay): TSO not found");
3503 barf("unblockThread");
3507 tso->link = END_TSO_QUEUE;
3508 tso->why_blocked = NotBlocked;
3509 tso->block_info.closure = NULL;
3510 APPEND_TO_RUN_QUEUE(tso);
3514 /* -----------------------------------------------------------------------------
3517 * Check the blackhole_queue for threads that can be woken up. We do
3518 * this periodically: before every GC, and whenever the run queue is
3521 * An elegant solution might be to just wake up all the blocked
3522 * threads with awakenBlockedQueue occasionally: they'll go back to
3523 * sleep again if the object is still a BLACKHOLE. Unfortunately this
3524 * doesn't give us a way to tell whether we've actually managed to
3525 * wake up any threads, so we would be busy-waiting.
3527 * -------------------------------------------------------------------------- */
3530 checkBlackHoles( void )
3533 rtsBool any_woke_up = rtsFalse;
3536 IF_DEBUG(scheduler, sched_belch("checking threads blocked on black holes"));
3538 // ASSUMES: sched_mutex
3539 prev = &blackhole_queue;
3540 t = blackhole_queue;
3541 while (t != END_TSO_QUEUE) {
3542 ASSERT(t->why_blocked == BlockedOnBlackHole);
3543 type = get_itbl(t->block_info.closure)->type;
3544 if (type != BLACKHOLE && type != CAF_BLACKHOLE) {
3545 t = unblockOneLocked(t);
3547 any_woke_up = rtsTrue;
3557 /* -----------------------------------------------------------------------------
3560 * The following function implements the magic for raising an
3561 * asynchronous exception in an existing thread.
3563 * We first remove the thread from any queue on which it might be
3564 * blocked. The possible blockages are MVARs and BLACKHOLE_BQs.
3566 * We strip the stack down to the innermost CATCH_FRAME, building
3567 * thunks in the heap for all the active computations, so they can
3568 * be restarted if necessary. When we reach a CATCH_FRAME, we build
3569 * an application of the handler to the exception, and push it on
3570 * the top of the stack.
3572 * How exactly do we save all the active computations? We create an
3573 * AP_STACK for every UpdateFrame on the stack. Entering one of these
3574 * AP_STACKs pushes everything from the corresponding update frame
3575 * upwards onto the stack. (Actually, it pushes everything up to the
3576 * next update frame plus a pointer to the next AP_STACK object.
3577 * Entering the next AP_STACK object pushes more onto the stack until we
3578 * reach the last AP_STACK object - at which point the stack should look
3579 * exactly as it did when we killed the TSO and we can continue
3580 * execution by entering the closure on top of the stack.
3582 * We can also kill a thread entirely - this happens if either (a) the
3583 * exception passed to raiseAsync is NULL, or (b) there's no
3584 * CATCH_FRAME on the stack. In either case, we strip the entire
3585 * stack and replace the thread with a zombie.
3587 * Locks: sched_mutex held upon entry nor exit.
3589 * -------------------------------------------------------------------------- */
3592 deleteThread(StgTSO *tso)
3594 if (tso->why_blocked != BlockedOnCCall &&
3595 tso->why_blocked != BlockedOnCCall_NoUnblockExc) {
3596 raiseAsync(tso,NULL);
3600 #ifdef FORKPROCESS_PRIMOP_SUPPORTED
3602 deleteThreadImmediately(StgTSO *tso)
3603 { // for forkProcess only:
3604 // delete thread without giving it a chance to catch the KillThread exception
3606 if (tso->what_next == ThreadComplete || tso->what_next == ThreadKilled) {
3610 if (tso->why_blocked != BlockedOnCCall &&
3611 tso->why_blocked != BlockedOnCCall_NoUnblockExc) {
3615 tso->what_next = ThreadKilled;
3620 raiseAsyncWithLock(StgTSO *tso, StgClosure *exception)
3622 /* When raising async exs from contexts where sched_mutex isn't held;
3623 use raiseAsyncWithLock(). */
3624 ACQUIRE_LOCK(&sched_mutex);
3625 raiseAsync(tso,exception);
3626 RELEASE_LOCK(&sched_mutex);
3630 raiseAsync(StgTSO *tso, StgClosure *exception)
3632 raiseAsync_(tso, exception, rtsFalse);
3636 raiseAsync_(StgTSO *tso, StgClosure *exception, rtsBool stop_at_atomically)
3638 StgRetInfoTable *info;
3641 // Thread already dead?
3642 if (tso->what_next == ThreadComplete || tso->what_next == ThreadKilled) {
3647 sched_belch("raising exception in thread %ld.", (long)tso->id));
3649 // Remove it from any blocking queues
3654 // The stack freezing code assumes there's a closure pointer on
3655 // the top of the stack, so we have to arrange that this is the case...
3657 if (sp[0] == (W_)&stg_enter_info) {
3661 sp[0] = (W_)&stg_dummy_ret_closure;
3667 // 1. Let the top of the stack be the "current closure"
3669 // 2. Walk up the stack until we find either an UPDATE_FRAME or a
3672 // 3. If it's an UPDATE_FRAME, then make an AP_STACK containing the
3673 // current closure applied to the chunk of stack up to (but not
3674 // including) the update frame. This closure becomes the "current
3675 // closure". Go back to step 2.
3677 // 4. If it's a CATCH_FRAME, then leave the exception handler on
3678 // top of the stack applied to the exception.
3680 // 5. If it's a STOP_FRAME, then kill the thread.
3682 // NB: if we pass an ATOMICALLY_FRAME then abort the associated
3689 info = get_ret_itbl((StgClosure *)frame);
3691 while (info->i.type != UPDATE_FRAME
3692 && (info->i.type != CATCH_FRAME || exception == NULL)
3693 && info->i.type != STOP_FRAME
3694 && (info->i.type != ATOMICALLY_FRAME || stop_at_atomically == rtsFalse))
3696 if (info->i.type == CATCH_RETRY_FRAME || info->i.type == ATOMICALLY_FRAME) {
3697 // IF we find an ATOMICALLY_FRAME then we abort the
3698 // current transaction and propagate the exception. In
3699 // this case (unlike ordinary exceptions) we do not care
3700 // whether the transaction is valid or not because its
3701 // possible validity cannot have caused the exception
3702 // and will not be visible after the abort.
3704 debugBelch("Found atomically block delivering async exception\n"));
3705 stmAbortTransaction(tso -> trec);
3706 tso -> trec = stmGetEnclosingTRec(tso -> trec);
3708 frame += stack_frame_sizeW((StgClosure *)frame);
3709 info = get_ret_itbl((StgClosure *)frame);
3712 switch (info->i.type) {
3714 case ATOMICALLY_FRAME:
3715 ASSERT(stop_at_atomically);
3716 ASSERT(stmGetEnclosingTRec(tso->trec) == NO_TREC);
3717 stmCondemnTransaction(tso -> trec);
3721 // R1 is not a register: the return convention for IO in
3722 // this case puts the return value on the stack, so we
3723 // need to set up the stack to return to the atomically
3724 // frame properly...
3725 tso->sp = frame - 2;
3726 tso->sp[1] = (StgWord) &stg_NO_FINALIZER_closure; // why not?
3727 tso->sp[0] = (StgWord) &stg_ut_1_0_unreg_info;
3729 tso->what_next = ThreadRunGHC;
3733 // If we find a CATCH_FRAME, and we've got an exception to raise,
3734 // then build the THUNK raise(exception), and leave it on
3735 // top of the CATCH_FRAME ready to enter.
3739 StgCatchFrame *cf = (StgCatchFrame *)frame;
3743 // we've got an exception to raise, so let's pass it to the
3744 // handler in this frame.
3746 raise = (StgClosure *)allocate(sizeofW(StgClosure)+1);
3747 TICK_ALLOC_SE_THK(1,0);
3748 SET_HDR(raise,&stg_raise_info,cf->header.prof.ccs);
3749 raise->payload[0] = exception;
3751 // throw away the stack from Sp up to the CATCH_FRAME.
3755 /* Ensure that async excpetions are blocked now, so we don't get
3756 * a surprise exception before we get around to executing the
3759 if (tso->blocked_exceptions == NULL) {
3760 tso->blocked_exceptions = END_TSO_QUEUE;
3763 /* Put the newly-built THUNK on top of the stack, ready to execute
3764 * when the thread restarts.
3767 sp[-1] = (W_)&stg_enter_info;
3769 tso->what_next = ThreadRunGHC;
3770 IF_DEBUG(sanity, checkTSO(tso));
3779 // First build an AP_STACK consisting of the stack chunk above the
3780 // current update frame, with the top word on the stack as the
3783 words = frame - sp - 1;
3784 ap = (StgAP_STACK *)allocate(PAP_sizeW(words));
3787 ap->fun = (StgClosure *)sp[0];
3789 for(i=0; i < (nat)words; ++i) {
3790 ap->payload[i] = (StgClosure *)*sp++;
3793 SET_HDR(ap,&stg_AP_STACK_info,
3794 ((StgClosure *)frame)->header.prof.ccs /* ToDo */);
3795 TICK_ALLOC_UP_THK(words+1,0);
3798 debugBelch("sched: Updating ");
3799 printPtr((P_)((StgUpdateFrame *)frame)->updatee);
3800 debugBelch(" with ");
3801 printObj((StgClosure *)ap);
3804 // Replace the updatee with an indirection - happily
3805 // this will also wake up any threads currently
3806 // waiting on the result.
3808 // Warning: if we're in a loop, more than one update frame on
3809 // the stack may point to the same object. Be careful not to
3810 // overwrite an IND_OLDGEN in this case, because we'll screw
3811 // up the mutable lists. To be on the safe side, don't
3812 // overwrite any kind of indirection at all. See also
3813 // threadSqueezeStack in GC.c, where we have to make a similar
3816 if (!closure_IND(((StgUpdateFrame *)frame)->updatee)) {
3817 // revert the black hole
3818 UPD_IND_NOLOCK(((StgUpdateFrame *)frame)->updatee,
3821 sp += sizeofW(StgUpdateFrame) - 1;
3822 sp[0] = (W_)ap; // push onto stack
3827 // We've stripped the entire stack, the thread is now dead.
3828 sp += sizeofW(StgStopFrame);
3829 tso->what_next = ThreadKilled;
3840 /* -----------------------------------------------------------------------------
3841 raiseExceptionHelper
3843 This function is called by the raise# primitve, just so that we can
3844 move some of the tricky bits of raising an exception from C-- into
3845 C. Who knows, it might be a useful re-useable thing here too.
3846 -------------------------------------------------------------------------- */
3849 raiseExceptionHelper (StgTSO *tso, StgClosure *exception)
3851 StgClosure *raise_closure = NULL;
3853 StgRetInfoTable *info;
3855 // This closure represents the expression 'raise# E' where E
3856 // is the exception raise. It is used to overwrite all the
3857 // thunks which are currently under evaluataion.
3861 // LDV profiling: stg_raise_info has THUNK as its closure
3862 // type. Since a THUNK takes at least MIN_UPD_SIZE words in its
3863 // payload, MIN_UPD_SIZE is more approprate than 1. It seems that
3864 // 1 does not cause any problem unless profiling is performed.
3865 // However, when LDV profiling goes on, we need to linearly scan
3866 // small object pool, where raise_closure is stored, so we should
3867 // use MIN_UPD_SIZE.
3869 // raise_closure = (StgClosure *)RET_STGCALL1(P_,allocate,
3870 // sizeofW(StgClosure)+1);
3874 // Walk up the stack, looking for the catch frame. On the way,
3875 // we update any closures pointed to from update frames with the
3876 // raise closure that we just built.
3880 info = get_ret_itbl((StgClosure *)p);
3881 next = p + stack_frame_sizeW((StgClosure *)p);
3882 switch (info->i.type) {
3885 // Only create raise_closure if we need to.
3886 if (raise_closure == NULL) {
3888 (StgClosure *)allocate(sizeofW(StgClosure)+MIN_UPD_SIZE);
3889 SET_HDR(raise_closure, &stg_raise_info, CCCS);
3890 raise_closure->payload[0] = exception;
3892 UPD_IND(((StgUpdateFrame *)p)->updatee,raise_closure);
3896 case ATOMICALLY_FRAME:
3897 IF_DEBUG(stm, debugBelch("Found ATOMICALLY_FRAME at %p\n", p));
3899 return ATOMICALLY_FRAME;
3905 case CATCH_STM_FRAME:
3906 IF_DEBUG(stm, debugBelch("Found CATCH_STM_FRAME at %p\n", p));
3908 return CATCH_STM_FRAME;
3914 case CATCH_RETRY_FRAME:
3923 /* -----------------------------------------------------------------------------
3924 findRetryFrameHelper
3926 This function is called by the retry# primitive. It traverses the stack
3927 leaving tso->sp referring to the frame which should handle the retry.
3929 This should either be a CATCH_RETRY_FRAME (if the retry# is within an orElse#)
3930 or should be a ATOMICALLY_FRAME (if the retry# reaches the top level).
3932 We skip CATCH_STM_FRAMEs because retries are not considered to be exceptions,
3933 despite the similar implementation.
3935 We should not expect to see CATCH_FRAME or STOP_FRAME because those should
3936 not be created within memory transactions.
3937 -------------------------------------------------------------------------- */
3940 findRetryFrameHelper (StgTSO *tso)
3943 StgRetInfoTable *info;
3947 info = get_ret_itbl((StgClosure *)p);
3948 next = p + stack_frame_sizeW((StgClosure *)p);
3949 switch (info->i.type) {
3951 case ATOMICALLY_FRAME:
3952 IF_DEBUG(stm, debugBelch("Found ATOMICALLY_FRAME at %p during retrry\n", p));
3954 return ATOMICALLY_FRAME;
3956 case CATCH_RETRY_FRAME:
3957 IF_DEBUG(stm, debugBelch("Found CATCH_RETRY_FRAME at %p during retrry\n", p));
3959 return CATCH_RETRY_FRAME;
3961 case CATCH_STM_FRAME:
3963 ASSERT(info->i.type != CATCH_FRAME);
3964 ASSERT(info->i.type != STOP_FRAME);
3971 /* -----------------------------------------------------------------------------
3972 resurrectThreads is called after garbage collection on the list of
3973 threads found to be garbage. Each of these threads will be woken
3974 up and sent a signal: BlockedOnDeadMVar if the thread was blocked
3975 on an MVar, or NonTermination if the thread was blocked on a Black
3978 Locks: sched_mutex isn't held upon entry nor exit.
3979 -------------------------------------------------------------------------- */
3982 resurrectThreads( StgTSO *threads )
3986 for (tso = threads; tso != END_TSO_QUEUE; tso = next) {
3987 next = tso->global_link;
3988 tso->global_link = all_threads;
3990 IF_DEBUG(scheduler, sched_belch("resurrecting thread %d", tso->id));
3992 switch (tso->why_blocked) {
3994 case BlockedOnException:
3995 /* Called by GC - sched_mutex lock is currently held. */
3996 raiseAsync(tso,(StgClosure *)BlockedOnDeadMVar_closure);
3998 case BlockedOnBlackHole:
3999 raiseAsync(tso,(StgClosure *)NonTermination_closure);
4002 raiseAsync(tso,(StgClosure *)BlockedIndefinitely_closure);
4005 /* This might happen if the thread was blocked on a black hole
4006 * belonging to a thread that we've just woken up (raiseAsync
4007 * can wake up threads, remember...).
4011 barf("resurrectThreads: thread blocked in a strange way");
4016 /* ----------------------------------------------------------------------------
4017 * Debugging: why is a thread blocked
4018 * [Also provides useful information when debugging threaded programs
4019 * at the Haskell source code level, so enable outside of DEBUG. --sof 7/02]
4020 ------------------------------------------------------------------------- */
4023 printThreadBlockage(StgTSO *tso)
4025 switch (tso->why_blocked) {
4027 debugBelch("is blocked on read from fd %ld", tso->block_info.fd);
4029 case BlockedOnWrite:
4030 debugBelch("is blocked on write to fd %ld", tso->block_info.fd);
4032 #if defined(mingw32_HOST_OS)
4033 case BlockedOnDoProc:
4034 debugBelch("is blocked on proc (request: %ld)", tso->block_info.async_result->reqID);
4037 case BlockedOnDelay:
4038 debugBelch("is blocked until %ld", tso->block_info.target);
4041 debugBelch("is blocked on an MVar");
4043 case BlockedOnException:
4044 debugBelch("is blocked on delivering an exception to thread %d",
4045 tso->block_info.tso->id);
4047 case BlockedOnBlackHole:
4048 debugBelch("is blocked on a black hole");
4051 debugBelch("is not blocked");
4053 #if defined(PARALLEL_HASKELL)
4055 debugBelch("is blocked on global address; local FM_BQ is %p (%s)",
4056 tso->block_info.closure, info_type(tso->block_info.closure));
4058 case BlockedOnGA_NoSend:
4059 debugBelch("is blocked on global address (no send); local FM_BQ is %p (%s)",
4060 tso->block_info.closure, info_type(tso->block_info.closure));
4063 case BlockedOnCCall:
4064 debugBelch("is blocked on an external call");
4066 case BlockedOnCCall_NoUnblockExc:
4067 debugBelch("is blocked on an external call (exceptions were already blocked)");
4070 debugBelch("is blocked on an STM operation");
4073 barf("printThreadBlockage: strange tso->why_blocked: %d for TSO %d (%d)",
4074 tso->why_blocked, tso->id, tso);
4079 printThreadStatus(StgTSO *tso)
4081 switch (tso->what_next) {
4083 debugBelch("has been killed");
4085 case ThreadComplete:
4086 debugBelch("has completed");
4089 printThreadBlockage(tso);
4094 printAllThreads(void)
4099 char time_string[TIME_STR_LEN], node_str[NODE_STR_LEN];
4100 ullong_format_string(TIME_ON_PROC(CurrentProc),
4101 time_string, rtsFalse/*no commas!*/);
4103 debugBelch("all threads at [%s]:\n", time_string);
4104 # elif defined(PARALLEL_HASKELL)
4105 char time_string[TIME_STR_LEN], node_str[NODE_STR_LEN];
4106 ullong_format_string(CURRENT_TIME,
4107 time_string, rtsFalse/*no commas!*/);
4109 debugBelch("all threads at [%s]:\n", time_string);
4111 debugBelch("all threads:\n");
4114 for (t = all_threads; t != END_TSO_QUEUE; t = t->global_link) {
4115 debugBelch("\tthread %d @ %p ", t->id, (void *)t);
4118 void *label = lookupThreadLabel(t->id);
4119 if (label) debugBelch("[\"%s\"] ",(char *)label);
4122 printThreadStatus(t);
4130 Print a whole blocking queue attached to node (debugging only).
4132 # if defined(PARALLEL_HASKELL)
4134 print_bq (StgClosure *node)
4136 StgBlockingQueueElement *bqe;
4140 debugBelch("## BQ of closure %p (%s): ",
4141 node, info_type(node));
4143 /* should cover all closures that may have a blocking queue */
4144 ASSERT(get_itbl(node)->type == BLACKHOLE_BQ ||
4145 get_itbl(node)->type == FETCH_ME_BQ ||
4146 get_itbl(node)->type == RBH ||
4147 get_itbl(node)->type == MVAR);
4149 ASSERT(node!=(StgClosure*)NULL); // sanity check
4151 print_bqe(((StgBlockingQueue*)node)->blocking_queue);
4155 Print a whole blocking queue starting with the element bqe.
4158 print_bqe (StgBlockingQueueElement *bqe)
4163 NB: In a parallel setup a BQ of an RBH must end with an RBH_Save closure;
4165 for (end = (bqe==END_BQ_QUEUE);
4166 !end; // iterate until bqe points to a CONSTR
4167 end = (get_itbl(bqe)->type == CONSTR) || (bqe->link==END_BQ_QUEUE),
4168 bqe = end ? END_BQ_QUEUE : bqe->link) {
4169 ASSERT(bqe != END_BQ_QUEUE); // sanity check
4170 ASSERT(bqe != (StgBlockingQueueElement *)NULL); // sanity check
4171 /* types of closures that may appear in a blocking queue */
4172 ASSERT(get_itbl(bqe)->type == TSO ||
4173 get_itbl(bqe)->type == BLOCKED_FETCH ||
4174 get_itbl(bqe)->type == CONSTR);
4175 /* only BQs of an RBH end with an RBH_Save closure */
4176 //ASSERT(get_itbl(bqe)->type != CONSTR || get_itbl(node)->type == RBH);
4178 switch (get_itbl(bqe)->type) {
4180 debugBelch(" TSO %u (%x),",
4181 ((StgTSO *)bqe)->id, ((StgTSO *)bqe));
4184 debugBelch(" BF (node=%p, ga=((%x, %d, %x)),",
4185 ((StgBlockedFetch *)bqe)->node,
4186 ((StgBlockedFetch *)bqe)->ga.payload.gc.gtid,
4187 ((StgBlockedFetch *)bqe)->ga.payload.gc.slot,
4188 ((StgBlockedFetch *)bqe)->ga.weight);
4191 debugBelch(" %s (IP %p),",
4192 (get_itbl(bqe) == &stg_RBH_Save_0_info ? "RBH_Save_0" :
4193 get_itbl(bqe) == &stg_RBH_Save_1_info ? "RBH_Save_1" :
4194 get_itbl(bqe) == &stg_RBH_Save_2_info ? "RBH_Save_2" :
4195 "RBH_Save_?"), get_itbl(bqe));
4198 barf("Unexpected closure type %s in blocking queue", // of %p (%s)",
4199 info_type((StgClosure *)bqe)); // , node, info_type(node));
4205 # elif defined(GRAN)
4207 print_bq (StgClosure *node)
4209 StgBlockingQueueElement *bqe;
4210 PEs node_loc, tso_loc;
4213 /* should cover all closures that may have a blocking queue */
4214 ASSERT(get_itbl(node)->type == BLACKHOLE_BQ ||
4215 get_itbl(node)->type == FETCH_ME_BQ ||
4216 get_itbl(node)->type == RBH);
4218 ASSERT(node!=(StgClosure*)NULL); // sanity check
4219 node_loc = where_is(node);
4221 debugBelch("## BQ of closure %p (%s) on [PE %d]: ",
4222 node, info_type(node), node_loc);
4225 NB: In a parallel setup a BQ of an RBH must end with an RBH_Save closure;
4227 for (bqe = ((StgBlockingQueue*)node)->blocking_queue, end = (bqe==END_BQ_QUEUE);
4228 !end; // iterate until bqe points to a CONSTR
4229 end = (get_itbl(bqe)->type == CONSTR) || (bqe->link==END_BQ_QUEUE), bqe = end ? END_BQ_QUEUE : bqe->link) {
4230 ASSERT(bqe != END_BQ_QUEUE); // sanity check
4231 ASSERT(bqe != (StgBlockingQueueElement *)NULL); // sanity check
4232 /* types of closures that may appear in a blocking queue */
4233 ASSERT(get_itbl(bqe)->type == TSO ||
4234 get_itbl(bqe)->type == CONSTR);
4235 /* only BQs of an RBH end with an RBH_Save closure */
4236 ASSERT(get_itbl(bqe)->type != CONSTR || get_itbl(node)->type == RBH);
4238 tso_loc = where_is((StgClosure *)bqe);
4239 switch (get_itbl(bqe)->type) {
4241 debugBelch(" TSO %d (%p) on [PE %d],",
4242 ((StgTSO *)bqe)->id, (StgTSO *)bqe, tso_loc);
4245 debugBelch(" %s (IP %p),",
4246 (get_itbl(bqe) == &stg_RBH_Save_0_info ? "RBH_Save_0" :
4247 get_itbl(bqe) == &stg_RBH_Save_1_info ? "RBH_Save_1" :
4248 get_itbl(bqe) == &stg_RBH_Save_2_info ? "RBH_Save_2" :
4249 "RBH_Save_?"), get_itbl(bqe));
4252 barf("Unexpected closure type %s in blocking queue of %p (%s)",
4253 info_type((StgClosure *)bqe), node, info_type(node));
4261 #if defined(PARALLEL_HASKELL)
4268 for (i=0, tso=run_queue_hd;
4269 tso != END_TSO_QUEUE;
4278 sched_belch(char *s, ...)
4282 #ifdef RTS_SUPPORTS_THREADS
4283 debugBelch("sched (task %p): ", osThreadId());
4284 #elif defined(PARALLEL_HASKELL)
4287 debugBelch("sched: ");