static void schedulePreLoop (void);
static void scheduleFindWork (Capability *cap);
#if defined(THREADED_RTS)
-static void scheduleYield (Capability **pcap, Task *task, rtsBool);
+static void scheduleYield (Capability **pcap, Task *task);
#endif
static void scheduleStartSignalHandlers (Capability *cap);
static void scheduleCheckBlockedThreads (Capability *cap);
rtsBool ready_to_gc;
#if defined(THREADED_RTS)
rtsBool first = rtsTrue;
- rtsBool force_yield = rtsFalse;
#endif
cap = initialCapability;
// ASSERT_FULL_CAPABILITY_INVARIANTS(cap,task);
}
- yield:
- scheduleYield(&cap,task,force_yield);
- force_yield = rtsFalse;
+ scheduleYield(&cap,task);
if (emptyRunQueue(cap)) continue; // look for work again
#endif
traceEventStopThread(cap, t, ret);
-#if defined(THREADED_RTS)
- // If ret is ThreadBlocked, and this Task is bound to the TSO that
- // blocked, we are in limbo - the TSO is now owned by whatever it
- // is blocked on, and may in fact already have been woken up,
- // perhaps even on a different Capability. It may be the case
- // that task->cap != cap. We better yield this Capability
- // immediately and return to normaility.
- if (ret == ThreadBlocked) {
- force_yield = rtsTrue;
- goto yield;
- }
-#endif
-
ASSERT_FULL_CAPABILITY_INVARIANTS(cap,task);
ASSERT(t->cap == cap);
// and also check the benchmarks in nofib/parallel for regressions.
static void
-scheduleYield (Capability **pcap, Task *task, rtsBool force_yield)
+scheduleYield (Capability **pcap, Task *task)
{
Capability *cap = *pcap;
// if we have work, and we don't need to give up the Capability, continue.
//
- // The force_yield flag is used when a bound thread blocks. This
- // is a particularly tricky situation: the current Task does not
- // own the TSO any more, since it is on some queue somewhere, and
- // might be woken up or manipulated by another thread at any time.
- // The TSO and Task might be migrated to another Capability.
- // Certain invariants might be in doubt, such as task->bound->cap
- // == cap. We have to yield the current Capability immediately,
- // no messing around.
- //
- if (!force_yield &&
- !shouldYieldCapability(cap,task) &&
+ if (!shouldYieldCapability(cap,task) &&
(!emptyRunQueue(cap) ||
!emptyInbox(cap) ||
sched_state >= SCHED_INTERRUPTING))
ASSERT(task->incall->tso == t);
if (t->what_next == ThreadComplete) {
- if (task->ret) {
+ if (task->incall->ret) {
// NOTE: return val is tso->sp[1] (see StgStartup.hc)
- *(task->ret) = (StgClosure *)task->incall->tso->sp[1];
+ *(task->incall->ret) = (StgClosure *)task->incall->tso->sp[1];
}
- task->stat = Success;
+ task->incall->stat = Success;
} else {
- if (task->ret) {
- *(task->ret) = NULL;
+ if (task->incall->ret) {
+ *(task->incall->ret) = NULL;
}
if (sched_state >= SCHED_INTERRUPTING) {
if (heap_overflow) {
- task->stat = HeapExhausted;
+ task->incall->stat = HeapExhausted;
} else {
- task->stat = Interrupted;
+ task->incall->stat = Interrupted;
}
} else {
- task->stat = Killed;
+ task->incall->stat = Killed;
}
}
#ifdef DEBUG
ACQUIRE_LOCK(&cap->lock);
ACQUIRE_LOCK(&cap->running_task->lock);
+ stopTimer(); // See #4074
+
pid = fork();
if (pid) { // parent
+ startTimer(); // #4074
+
RELEASE_LOCK(&sched_mutex);
RELEASE_LOCK(&cap->lock);
RELEASE_LOCK(&cap->running_task->lock);
// Wipe our spare workers list, they no longer exist. New
// workers will be created if necessary.
cap->spare_workers = NULL;
- cap->returning_tasks_hd = NULL;
+ cap->n_spare_workers = 0;
+ cap->returning_tasks_hd = NULL;
cap->returning_tasks_tl = NULL;
#endif
* the whole system.
*
* The Haskell thread making the C call is put to sleep for the
- * duration of the call, on the susepended_ccalling_threads queue. We
+ * duration of the call, on the suspended_ccalling_threads queue. We
* give out a token to the task, which it can use to resume the thread
* on return from the C function.
+ *
+ * If this is an interruptible C call, this means that the FFI call may be
+ * unceremoniously terminated and should be scheduled on an
+ * unbound worker thread.
* ------------------------------------------------------------------------- */
void *
-suspendThread (StgRegTable *reg)
+suspendThread (StgRegTable *reg, rtsBool interruptible)
{
Capability *cap;
int saved_errno;
threadPaused(cap,tso);
- if ((tso->flags & TSO_BLOCKEX) == 0) {
- tso->why_blocked = BlockedOnCCall;
- tso->flags |= TSO_BLOCKEX;
- tso->flags &= ~TSO_INTERRUPTIBLE;
+ if (interruptible) {
+ tso->why_blocked = BlockedOnCCall_Interruptible;
} else {
- tso->why_blocked = BlockedOnCCall_NoUnblockExc;
+ tso->why_blocked = BlockedOnCCall;
}
// Hand back capability
traceEventRunThread(cap, tso);
- if (tso->why_blocked == BlockedOnCCall) {
+ /* Reset blocking status */
+ tso->why_blocked = NotBlocked;
+
+ if ((tso->flags & TSO_BLOCKEX) == 0) {
// avoid locking the TSO if we don't have to
if (tso->blocked_exceptions != END_BLOCKED_EXCEPTIONS_QUEUE) {
- awakenBlockedExceptionQueue(cap,tso);
+ maybePerformBlockedException(cap,tso);
}
- tso->flags &= ~(TSO_BLOCKEX | TSO_INTERRUPTIBLE);
}
- /* Reset blocking status */
- tso->why_blocked = NotBlocked;
-
cap->r.rCurrentTSO = tso;
cap->in_haskell = rtsTrue;
errno = saved_errno;
if (cpu == cap->no) {
appendToRunQueue(cap,tso);
} else {
- traceEventMigrateThread (cap, tso, capabilities[cpu].no);
- wakeupThreadOnCapability(cap, &capabilities[cpu], tso);
+ migrateThread(cap, tso, &capabilities[cpu]);
}
#else
appendToRunQueue(cap,tso);
tso->cap = cap;
task->incall->tso = tso;
- task->ret = ret;
- task->stat = NoStatus;
+ task->incall->ret = ret;
+ task->incall->stat = NoStatus;
appendToRunQueue(cap,tso);
cap = schedule(cap,task);
- ASSERT(task->stat != NoStatus);
+ ASSERT(task->incall->stat != NoStatus);
ASSERT_FULL_CAPABILITY_INVARIANTS(cap,task);
debugTrace(DEBUG_sched, "bound thread (%lu) finished", (unsigned long)id);
}
void
-exitScheduler(
- rtsBool wait_foreign
-#if !defined(THREADED_RTS)
- __attribute__((unused))
-#endif
-)
+exitScheduler (rtsBool wait_foreign USED_IF_THREADS)
/* see Capability.c, shutdownCapability() */
{
Task *task = NULL;
// we must own all Capabilities.
if (tso->why_blocked != BlockedOnCCall &&
- tso->why_blocked != BlockedOnCCall_NoUnblockExc) {
+ tso->why_blocked != BlockedOnCCall_Interruptible) {
throwToSingleThreaded(tso->cap,tso,NULL);
}
}
// like deleteThread(), but we delete threads in foreign calls, too.
if (tso->why_blocked == BlockedOnCCall ||
- tso->why_blocked == BlockedOnCCall_NoUnblockExc) {
- unblockOne(cap,tso);
+ tso->why_blocked == BlockedOnCCall_Interruptible) {
tso->what_next = ThreadKilled;
+ appendToRunQueue(tso->cap, tso);
} else {
deleteThread(cap,tso);
}
* can wake up threads, remember...).
*/
continue;
+ case BlockedOnMsgThrowTo:
+ // This can happen if the target is masking, blocks on a
+ // black hole, and then is found to be unreachable. In
+ // this case, we want to let the target wake up and carry
+ // on, and do nothing to this thread.
+ continue;
default:
barf("resurrectThreads: thread blocked in a strange way: %d",
tso->why_blocked);