#include "Proftimer.h"
#include "ProfHeap.h"
#include "Weak.h"
-#include "eventlog/EventLog.h"
#include "sm/GC.h" // waitForGcThreads, releaseGCThreads, N
#include "Sparks.h"
#include "Capability.h"
static void deleteThread_(Capability *cap, StgTSO *tso);
#endif
-#ifdef DEBUG
-static char *whatNext_strs[] = {
- [0] = "(unknown)",
- [ThreadRunGHC] = "ThreadRunGHC",
- [ThreadInterpret] = "ThreadInterpret",
- [ThreadKilled] = "ThreadKilled",
- [ThreadRelocated] = "ThreadRelocated",
- [ThreadComplete] = "ThreadComplete"
-};
-#endif
-
/* -----------------------------------------------------------------------------
* Putting a thread on the run queue: different scheduling policies
* -------------------------------------------------------------------------- */
// The sched_mutex is *NOT* held
// NB. on return, we still hold a capability.
- debugTrace (DEBUG_sched,
- "### NEW SCHEDULER LOOP (task: %p, cap: %p)",
- task, initialCapability);
+ debugTrace (DEBUG_sched, "cap %d: schedule()", initialCapability->no);
schedulePreLoop();
if (bound) {
if (bound == task) {
- debugTrace(DEBUG_sched,
- "### Running thread %lu in bound thread", (unsigned long)t->id);
// yes, the Haskell thread is bound to the current native thread
} else {
debugTrace(DEBUG_sched,
- "### thread %lu bound to another OS thread", (unsigned long)t->id);
+ "thread %lu bound to another OS thread",
+ (unsigned long)t->id);
// no, bound to a different Haskell thread: pass to that thread
pushOnRunQueue(cap,t);
continue;
// The thread we want to run is unbound.
if (task->tso) {
debugTrace(DEBUG_sched,
- "### this OS thread cannot run thread %lu", (unsigned long)t->id);
+ "this OS thread cannot run thread %lu",
+ (unsigned long)t->id);
// no, the current native thread is bound to a different
// Haskell thread, so pass it to any worker thread
pushOnRunQueue(cap,t);
// that.
cap->r.rCurrentTSO = t;
- debugTrace(DEBUG_sched, "-->> running thread %ld %s ...",
- (long)t->id, whatNext_strs[t->what_next]);
-
startHeapProfTimer();
// Check for exceptions blocked on this thread
}
#endif
- postEvent(cap, EVENT_RUN_THREAD, t->id, 0);
+ traceSchedEvent(cap, EVENT_RUN_THREAD, t, 0);
switch (prev_what_next) {
t->saved_winerror = GetLastError();
#endif
- postEvent (cap, EVENT_STOP_THREAD, t->id, ret);
+ traceSchedEvent (cap, EVENT_STOP_THREAD, t, ret);
#if defined(THREADED_RTS)
// If ret is ThreadBlocked, and this Task is bound to the TSO that
// that task->cap != cap. We better yield this Capability
// immediately and return to normaility.
if (ret == ThreadBlocked) {
- debugTrace(DEBUG_sched,
- "--<< thread %lu (%s) stopped: blocked",
- (unsigned long)t->id, whatNext_strs[t->what_next]);
force_yield = rtsTrue;
goto yield;
}
debugTrace(DEBUG_sched, "pushing thread %lu to capability %d", (unsigned long)t->id, free_caps[i]->no);
appendToRunQueue(free_caps[i],t);
- postEvent (cap, EVENT_MIGRATE_THREAD, t->id, free_caps[i]->no);
+ traceSchedEvent (cap, EVENT_MIGRATE_THREAD, t, free_caps[i]->no);
if (t->bound) { t->bound->cap = free_caps[i]; }
t->cap = free_caps[i];
if (spark != NULL) {
debugTrace(DEBUG_sched, "pushing spark %p to capability %d", spark, free_caps[i]->no);
- postEvent(free_caps[i], EVENT_STEAL_SPARK, t->id, cap->no);
+ traceSchedEvent(free_caps[i], EVENT_STEAL_SPARK, t, cap->no);
newSpark(&(free_caps[i]->r), spark);
}
// partially-evaluated thunks on the heap.
throwToSingleThreaded_(cap, t, NULL, rtsTrue);
- ASSERT(get_itbl((StgClosure *)t->sp)->type == ATOMICALLY_FRAME);
+// ASSERT(get_itbl((StgClosure *)t->sp)->type == ATOMICALLY_FRAME);
}
}
debugTrace(DEBUG_sched,
"--<< thread %ld (%s) stopped: requesting a large block (size %ld)\n",
- (long)t->id, whatNext_strs[t->what_next], blocks);
+ (long)t->id, what_next_strs[t->what_next], blocks);
// don't do this if the nursery is (nearly) full, we'll GC first.
if (cap->r.rCurrentNursery->link != NULL ||
if (cap->r.rCurrentNursery->u.back != NULL) {
cap->r.rCurrentNursery->u.back->link = bd;
} else {
-#if !defined(THREADED_RTS)
- ASSERT(g0s0->blocks == cap->r.rCurrentNursery &&
- g0s0 == cap->r.rNursery);
-#endif
cap->r.rNursery->blocks = bd;
}
cap->r.rCurrentNursery->u.back = bd;
{
bdescr *x;
for (x = bd; x < bd + blocks; x++) {
- x->step = cap->r.rNursery;
- x->gen_no = 0;
+ initBdescr(x,cap->r.rNursery);
+ x->free = x->start;
x->flags = 0;
}
}
}
}
- debugTrace(DEBUG_sched,
- "--<< thread %ld (%s) stopped: HeapOverflow",
- (long)t->id, whatNext_strs[t->what_next]);
-
if (cap->r.rHpLim == NULL || cap->context_switch) {
// Sometimes we miss a context switch, e.g. when calling
// primitives in a tight loop, MAYBE_GC() doesn't check the
static void
scheduleHandleStackOverflow (Capability *cap, Task *task, StgTSO *t)
{
- debugTrace (DEBUG_sched,
- "--<< thread %ld (%s) stopped, StackOverflow",
- (long)t->id, whatNext_strs[t->what_next]);
-
/* just adjust the stack for this thread, then pop it back
* on the run queue.
*/
if (t->what_next != prev_what_next) {
debugTrace(DEBUG_sched,
"--<< thread %ld (%s) stopped to switch evaluators",
- (long)t->id, whatNext_strs[t->what_next]);
- } else {
- debugTrace(DEBUG_sched,
- "--<< thread %ld (%s) stopped, yielding",
- (long)t->id, whatNext_strs[t->what_next]);
+ (long)t->id, what_next_strs[t->what_next]);
}
#endif
// exception, see maybePerformBlockedException().
#ifdef DEBUG
- if (traceClass(DEBUG_sched)) {
- debugTraceBegin("--<< thread %lu (%s) stopped: ",
- (unsigned long)t->id, whatNext_strs[t->what_next]);
- printThreadBlockage(t);
- debugTraceEnd();
- }
+ traceThreadStatus(DEBUG_sched, t);
#endif
}
* We also end up here if the thread kills itself with an
* uncaught exception, see Exception.cmm.
*/
- debugTrace(DEBUG_sched, "--++ thread %lu (%s) finished",
- (unsigned long)t->id, whatNext_strs[t->what_next]);
// blocked exceptions can now complete, even if the thread was in
// blocked mode (see #2910). This unconditionally calls
if (gc_type == PENDING_GC_SEQ)
{
- postEvent(cap, EVENT_REQUEST_SEQ_GC, 0, 0);
+ traceSchedEvent(cap, EVENT_REQUEST_SEQ_GC, 0, 0);
+ }
+ else
+ {
+ traceSchedEvent(cap, EVENT_REQUEST_PAR_GC, 0, 0);
+ debugTrace(DEBUG_sched, "ready_to_gc, grabbing GC threads");
+ }
+
+ // do this while the other Capabilities stop:
+ if (cap) scheduleCheckBlackHoles(cap);
+
+ if (gc_type == PENDING_GC_SEQ)
+ {
// single-threaded GC: grab all the capabilities
for (i=0; i < n_capabilities; i++) {
debugTrace(DEBUG_sched, "ready_to_gc, grabbing all the capabilies (%d/%d)", i, n_capabilities);
{
// multi-threaded GC: make sure all the Capabilities donate one
// GC thread each.
- postEvent(cap, EVENT_REQUEST_PAR_GC, 0, 0);
- debugTrace(DEBUG_sched, "ready_to_gc, grabbing GC threads");
-
waitForGcThreads(cap);
}
-#endif
- // so this happens periodically:
+#else /* !THREADED_RTS */
+
+ // do this while the other Capabilities stop:
if (cap) scheduleCheckBlackHoles(cap);
-
+
+#endif
+
IF_DEBUG(scheduler, printAllThreads());
delete_threads_and_gc:
heap_census = scheduleNeedHeapProfile(rtsTrue);
#if defined(THREADED_RTS)
- postEvent(cap, EVENT_GC_START, 0, 0);
- debugTrace(DEBUG_sched, "doing GC");
+ traceSchedEvent(cap, EVENT_GC_START, 0, 0);
// reset waiting_for_gc *before* GC, so that when the GC threads
// emerge they don't immediately re-enter the GC.
waiting_for_gc = 0;
#else
GarbageCollect(force_major || heap_census, 0, cap);
#endif
- postEvent(cap, EVENT_GC_END, 0, 0);
+ traceSchedEvent(cap, EVENT_GC_END, 0, 0);
if (recent_activity == ACTIVITY_INACTIVE && force_major)
{
initTimer();
startTimer();
+#if defined(THREADED_RTS)
+ cap = ioManagerStartCap(cap);
+#endif
+
cap = rts_evalStableIO(cap, entry, NULL); // run the action
rts_checkSchedStatus("forkProcess",cap);
task = cap->running_task;
tso = cap->r.rCurrentTSO;
- postEvent(cap, EVENT_STOP_THREAD, tso->id, THREAD_SUSPENDED_FOREIGN_CALL);
- debugTrace(DEBUG_sched,
- "thread %lu did a safe foreign call",
- (unsigned long)cap->r.rCurrentTSO->id);
+ traceSchedEvent(cap, EVENT_STOP_THREAD, tso, THREAD_SUSPENDED_FOREIGN_CALL);
// XXX this might not be necessary --SDM
tso->what_next = ThreadRunGHC;
RELEASE_LOCK(&cap->lock);
-#if defined(THREADED_RTS)
- /* Preparing to leave the RTS, so ensure there's a native thread/task
- waiting to take over.
- */
- debugTrace(DEBUG_sched, "thread %lu: leaving RTS", (unsigned long)tso->id);
-#endif
-
errno = saved_errno;
#if mingw32_HOST_OS
SetLastError(saved_winerror);
task->suspended_tso = NULL;
tso->_link = END_TSO_QUEUE; // no write barrier reqd
- postEvent(cap, EVENT_RUN_THREAD, tso->id, 0);
- debugTrace(DEBUG_sched, "thread %lu: re-entering RTS", (unsigned long)tso->id);
+ traceSchedEvent(cap, EVENT_RUN_THREAD, tso, tso->what_next);
if (tso->why_blocked == BlockedOnCCall) {
// avoid locking the TSO if we don't have to
if (cpu == cap->no) {
appendToRunQueue(cap,tso);
} else {
- postEvent (cap, EVENT_MIGRATE_THREAD, tso->id, capabilities[cpu].no);
+ traceSchedEvent (cap, EVENT_MIGRATE_THREAD, tso, capabilities[cpu].no);
wakeupThreadOnCapability(cap, &capabilities[cpu], tso);
}
#else
for (i = 0; i < n_capabilities; i++) {
shutdownCapability(&capabilities[i], task, wait_foreign);
}
- boundTaskExiting(task);
}
#endif
+
+ boundTaskExiting(task);
}
void
// while we are moving the TSO:
lockClosure((StgClosure *)tso);
- if (tso->stack_size >= tso->max_stack_size && !(tso->flags & TSO_BLOCKEX)) {
+ if (tso->stack_size >= tso->max_stack_size
+ && !(tso->flags & TSO_BLOCKEX)) {
// NB. never raise a StackOverflow exception if the thread is
// inside Control.Exceptino.block. It is impractical to protect
// against stack overflow exceptions, since virtually anything
// can raise one (even 'catch'), so this is the only sensible
// thing to do here. See bug #767.
+ //
+
+ if (tso->flags & TSO_SQUEEZED) {
+ return tso;
+ }
+ // #3677: In a stack overflow situation, stack squeezing may
+ // reduce the stack size, but we don't know whether it has been
+ // reduced enough for the stack check to succeed if we try
+ // again. Fortunately stack squeezing is idempotent, so all we
+ // need to do is record whether *any* squeezing happened. If we
+ // are at the stack's absolute -K limit, and stack squeezing
+ // happened, then we try running the thread again. The
+ // TSO_SQUEEZED flag is set by threadPaused() to tell us whether
+ // squeezing happened or not.
debugTrace(DEBUG_gc,
"threadStackOverflow of TSO %ld (%p): stack too large (now %ld; max is %ld)",
return tso;
}
+
+ // We also want to avoid enlarging the stack if squeezing has
+ // already released some of it. However, we don't want to get into
+ // a pathalogical situation where a thread has a nearly full stack
+ // (near its current limit, but not near the absolute -K limit),
+ // keeps allocating a little bit, squeezing removes a little bit,
+ // and then it runs again. So to avoid this, if we squeezed *and*
+ // there is still less than BLOCK_SIZE_W words free, then we enlarge
+ // the stack anyway.
+ if ((tso->flags & TSO_SQUEEZED) &&
+ ((W_)(tso->sp - tso->stack) >= BLOCK_SIZE_W)) {
+ unlockTSO(tso);
+ return tso;
+ }
+
/* Try to double the current stack size. If that takes us over the
* maximum stack size for this thread, then use the maximum instead
* (that is, unless we're already at or over the max size and we
"increasing stack size from %ld words to %d.",
(long)tso->stack_size, new_stack_size);
- dest = (StgTSO *)allocateLocal(cap,new_tso_size);
+ dest = (StgTSO *)allocate(cap,new_tso_size);
TICK_ALLOC_TSO(new_stack_size,0);
/* copy the TSO block and the old stack into the new area */
// Only create raise_closure if we need to.
if (raise_closure == NULL) {
raise_closure =
- (StgThunk *)allocateLocal(cap,sizeofW(StgThunk)+1);
+ (StgThunk *)allocate(cap,sizeofW(StgThunk)+1);
SET_HDR(raise_closure, &stg_raise_info, CCCS);
raise_closure->payload[0] = exception;
}
case CATCH_STM_FRAME: {
StgTRecHeader *trec = tso -> trec;
- StgTRecHeader *outer = stmGetEnclosingTRec(trec);
+ StgTRecHeader *outer = trec -> enclosing_trec;
debugTrace(DEBUG_stm,
"found CATCH_STM_FRAME at %p during retry", p);
debugTrace(DEBUG_stm, "trec=%p outer=%p", trec, outer);
switch (tso->why_blocked) {
case BlockedOnMVar:
- case BlockedOnException:
/* Called by GC - sched_mutex lock is currently held. */
throwToSingleThreaded(cap, tso,
- (StgClosure *)blockedOnDeadMVar_closure);
+ (StgClosure *)blockedIndefinitelyOnMVar_closure);
break;
case BlockedOnBlackHole:
throwToSingleThreaded(cap, tso,
break;
case BlockedOnSTM:
throwToSingleThreaded(cap, tso,
- (StgClosure *)blockedIndefinitely_closure);
+ (StgClosure *)blockedIndefinitelyOnSTM_closure);
break;
case NotBlocked:
/* This might happen if the thread was blocked on a black hole
* can wake up threads, remember...).
*/
continue;
+ case BlockedOnException:
+ // throwTo should never block indefinitely: if the target
+ // thread dies or completes, throwTo returns.
+ barf("resurrectThreads: thread BlockedOnException");
+ break;
default:
barf("resurrectThreads: thread blocked in a strange way");
}
{
StgTSO *tso, *next;
Capability *cap;
+ Task *task, *saved_task;;
step *step;
+ task = myTask();
+ cap = task->cap;
+
for (tso = threads; tso != END_TSO_QUEUE; tso = next) {
next = tso->global_link;
debugTrace(DEBUG_sched, "performing blocked throwTo to thread %lu", (unsigned long)tso->id);
- cap = tso->cap;
- maybePerformBlockedException(cap, tso);
- }
+ // We must pretend this Capability belongs to the current Task
+ // for the time being, as invariants will be broken otherwise.
+ // In fact the current Task has exclusive access to the systme
+ // at this point, so this is just bookkeeping:
+ task->cap = tso->cap;
+ saved_task = tso->cap->running_task;
+ tso->cap->running_task = task;
+ maybePerformBlockedException(tso->cap, tso);
+ tso->cap->running_task = saved_task;
+ }
+
+ // Restore our original Capability:
+ task->cap = cap;
}
projects / ghc-hetmet.git / blobdiff