/* ---------------------------------------------------------------------------
- * $Id: Schedule.c,v 1.135 2002/04/01 11:18:19 panne Exp $
+ * $Id: Schedule.c,v 1.137 2002/04/13 05:33:02 sof Exp $
*
* (c) The GHC Team, 1998-2000
*
#include "OSThreads.h"
#include "Task.h"
+#ifdef HAVE_SYS_TYPES_H
+#include <sys/types.h>
+#endif
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+
#include <stdarg.h>
//@node Variables and Data structures, Prototypes, Includes, Main scheduling code
ACQUIRE_LOCK(&sched_mutex);
#if defined(RTS_SUPPORTS_THREADS)
- /* Check to see whether there are any worker threads
- waiting to deposit external call results. If so,
- yield our capability */
- yieldToReturningWorker(&sched_mutex, cap);
-
waitForWorkCapability(&sched_mutex, &cap, rtsFalse);
+#else
+ /* simply initialise it in the non-threaded case */
+ grabCapability(&cap);
#endif
#if defined(GRAN)
IF_DEBUG(scheduler, printAllThreads());
+#if defined(RTS_SUPPORTS_THREADS)
+ /* Check to see whether there are any worker threads
+ waiting to deposit external call results. If so,
+ yield our capability */
+ yieldToReturningWorker(&sched_mutex, cap);
+#endif
+
/* If we're interrupted (the user pressed ^C, or some other
* termination condition occurred), kill all the currently running
* threads.
*prev = m->link;
m->stat = Success;
broadcastCondition(&m->wakeup);
+#ifdef DEBUG
+ free(m->tso->label);
+#endif
break;
case ThreadKilled:
if (m->ret) *(m->ret) = NULL;
m->stat = Killed;
}
broadcastCondition(&m->wakeup);
+#ifdef DEBUG
+ free(m->tso->label);
+#endif
break;
default:
break;
StgMainThread *m = main_threads;
if (m->tso->what_next == ThreadComplete
|| m->tso->what_next == ThreadKilled) {
+#ifdef DEBUG
+ free(m->tso->label);
+#endif
main_threads = main_threads->link;
if (m->tso->what_next == ThreadComplete) {
/* we finished successfully, fill in the return value */
for (m = main_threads; m != NULL; m = m->link) {
switch (m->tso->why_blocked) {
case BlockedOnBlackHole:
- raiseAsync(m->tso, (StgClosure *)NonTermination_closure);
+ raiseAsyncWithLock(m->tso, (StgClosure *)NonTermination_closure);
break;
case BlockedOnException:
case BlockedOnMVar:
- raiseAsync(m->tso, (StgClosure *)Deadlock_closure);
+ raiseAsyncWithLock(m->tso, (StgClosure *)Deadlock_closure);
break;
default:
barf("deadlock: main thread blocked in a strange way");
m = main_threads;
switch (m->tso->why_blocked) {
case BlockedOnBlackHole:
- raiseAsync(m->tso, (StgClosure *)NonTermination_closure);
+ raiseAsyncWithLock(m->tso, (StgClosure *)NonTermination_closure);
break;
case BlockedOnException:
case BlockedOnMVar:
- raiseAsync(m->tso, (StgClosure *)Deadlock_closure);
+ raiseAsyncWithLock(m->tso, (StgClosure *)Deadlock_closure);
break;
default:
barf("deadlock: main thread blocked in a strange way");
IF_DEBUG(sanity,checkTSO(t));
#endif
- grabCapability(&cap);
cap->r.rCurrentTSO = t;
/* context switches are now initiated by the timer signal, unless
default:
barf("schedule: invalid thread return code %d", (int)ret);
}
-
-#if defined(RTS_SUPPORTS_THREADS)
- /* I don't understand what this re-grab is doing -- sof */
- grabCapability(&cap);
-#endif
#ifdef PROFILING
if (RtsFlags.ProfFlags.profileInterval==0 || performHeapProfile) {
}
/* ---------------------------------------------------------------------------
+ * Singleton fork(). Do not copy any running threads.
+ * ------------------------------------------------------------------------- */
+
+StgInt forkProcess(StgTSO* tso) {
+
+#ifndef mingw32_TARGET_OS
+ pid_t pid;
+ StgTSO* t,*next;
+
+ IF_DEBUG(scheduler,sched_belch("forking!"));
+
+ pid = fork();
+ if (pid) { /* parent */
+
+ /* just return the pid */
+
+ } else { /* child */
+ /* wipe all other threads */
+ run_queue_hd = tso;
+ tso->link = END_TSO_QUEUE;
+
+ /* DO NOT TOUCH THE QUEUES directly because most of the code around
+ us is picky about finding the threat still in its queue when
+ handling the deleteThread() */
+
+ for (t = all_threads; t != END_TSO_QUEUE; t = next) {
+ next = t->link;
+ if (t->id != tso->id) {
+ deleteThread(t);
+ }
+ }
+ }
+ return pid;
+#else /* mingw32 */
+ barf("forkProcess#: primop not implemented for mingw32, sorry!");
+ return -1;
+#endif /* mingw32 */
+}
+
+/* ---------------------------------------------------------------------------
* deleteAllThreads(): kill all the live threads.
*
* This is used when we catch a user interrupt (^C), before performing
StgInt
suspendThread( StgRegTable *reg,
rtsBool concCall
-#if !defined(RTS_SUPPORTS_THREADS)
+#if !defined(RTS_SUPPORTS_THREADS) && !defined(DEBUG)
STG_UNUSED
#endif
)
ACQUIRE_LOCK(&sched_mutex);
IF_DEBUG(scheduler,
- sched_belch("thread %d did a _ccall_gc", cap->r.rCurrentTSO->id));
+ sched_belch("thread %d did a _ccall_gc (is_concurrent: %d)", cap->r.rCurrentTSO->id,concCall));
threadPaused(cap->r.rCurrentTSO);
cap->r.rCurrentTSO->link = suspended_ccalling_threads;
#if defined(RTS_SUPPORTS_THREADS)
/* Wait for permission to re-enter the RTS with the result. */
if ( concCall ) {
+ ACQUIRE_LOCK(&sched_mutex);
grabReturnCapability(&sched_mutex, &cap);
} else {
grabCapability(&cap);
return tso->id;
}
+#ifdef DEBUG
+void labelThread(StgTSO *tso, char *label)
+{
+ int len;
+ void *buf;
+
+ /* Caveat: Once set, you can only set the thread name to "" */
+ len = strlen(label)+1;
+ buf = realloc(tso->label,len);
+ if (buf == NULL) {
+ fprintf(stderr,"insufficient memory for labelThread!\n");
+ free(tso->label);
+ } else
+ strncpy(buf,label,len);
+ tso->label = buf;
+}
+#endif /* DEBUG */
+
/* ---------------------------------------------------------------------------
Create a new thread.
#endif
tso->what_next = ThreadEnterGHC;
+#ifdef DEBUG
+ tso->label = NULL;
+#endif
+
/* tso->id needs to be unique. For now we use a heavyweight mutex to
* protect the increment operation on next_thread_id.
* In future, we could use an atomic increment instead.
SchedulerStatus
waitThread(StgTSO *tso, /*out*/StgClosure **ret)
{
+ IF_DEBUG(scheduler, sched_belch("== scheduler: waiting for thread (%d)\n", tso->id));
#if defined(THREADED_RTS)
return waitThread_(tso,ret, rtsFalse);
#else
SchedulerStatus stat;
ACQUIRE_LOCK(&sched_mutex);
+ IF_DEBUG(scheduler, sched_belch("== scheduler: waiting for thread (%d)\n", tso->id));
m = stgMallocBytes(sizeof(StgMainThread), "waitThread");
NB: only the type of the blocking queue is different in GranSim and GUM
the operations on the queue-elements are the same
long live polymorphism!
+
+ Locks: sched_mutex is held upon entry and exit.
+
*/
static void
unblockThread(StgTSO *tso)
unblockThread(StgTSO *tso)
{
StgTSO *t, **last;
+
+ /* To avoid locking unnecessarily. */
+ if (tso->why_blocked == NotBlocked) {
+ return;
+ }
ACQUIRE_LOCK(&sched_mutex);
switch (tso->why_blocked) {
- case NotBlocked:
- return; /* not blocked */
-
case BlockedOnMVar:
ASSERT(get_itbl(tso->block_info.closure)->type == MVAR);
{
* CATCH_FRAME on the stack. In either case, we strip the entire
* stack and replace the thread with a zombie.
*
+ * Locks: sched_mutex not held upon entry nor exit.
+ *
* -------------------------------------------------------------------------- */
void
}
void
+raiseAsyncWithLock(StgTSO *tso, StgClosure *exception)
+{
+ /* When raising async exs from contexts where sched_mutex is held;
+ use raiseAsyncWithLock(). */
+ RELEASE_LOCK(&sched_mutex);
+ raiseAsync(tso,exception);
+ ACQUIRE_LOCK(&sched_mutex);
+}
+
+void
raiseAsync(StgTSO *tso, StgClosure *exception)
{
StgUpdateFrame* su = tso->su;
/* Remove it from any blocking queues */
unblockThread(tso);
+ IF_DEBUG(scheduler, sched_belch("raising exception in thread %ld.", tso->id));
/* The stack freezing code assumes there's a closure pointer on
* the top of the stack. This isn't always the case with compiled
* code, so we have to push a dummy closure on the top which just
up and sent a signal: BlockedOnDeadMVar if the thread was blocked
on an MVar, or NonTermination if the thread was blocked on a Black
Hole.
+
+ Locks: sched_mutex isn't held upon entry nor exit.
-------------------------------------------------------------------------- */
void
switch (tso->why_blocked) {
case BlockedOnMVar:
case BlockedOnException:
- raiseAsync(tso,(StgClosure *)BlockedOnDeadMVar_closure);
+ /* Called by GC - sched_mutex lock is currently held. */
+ raiseAsyncWithLock(tso,(StgClosure *)BlockedOnDeadMVar_closure);
break;
case BlockedOnBlackHole:
- raiseAsync(tso,(StgClosure *)NonTermination_closure);
+ raiseAsyncWithLock(tso,(StgClosure *)NonTermination_closure);
break;
case NotBlocked:
/* This might happen if the thread was blocked on a black hole
*
* This is only done in a deadlock situation in order to avoid
* performance overhead in the normal case.
+ *
+ * Locks: sched_mutex is held upon entry and exit.
* -------------------------------------------------------------------------- */
static void
*/
IF_DEBUG(scheduler,
sched_belch("thread %d is blocked on itself", t->id));
- raiseAsync(t, (StgClosure *)NonTermination_closure);
+ raiseAsyncWithLock(t, (StgClosure *)NonTermination_closure);
goto done;
}
else {
for (t = all_threads; t != END_TSO_QUEUE; t = t->global_link) {
fprintf(stderr, "\tthread %d ", t->id);
+ if (t->label) fprintf(stderr,"[\"%s\"] ",t->label);
printThreadStatus(t);
fprintf(stderr,"\n");
}