/* -----------------------------------------------------------------------------
- * $Id: Schedule.h,v 1.18 2000/04/14 15:18:07 sewardj Exp $
*
- * (c) The GHC Team 1998-1999
+ * (c) The GHC Team 1998-2005
*
* Prototypes for functions in Schedule.c
* (RTS internal scheduler interface)
*
* -------------------------------------------------------------------------*/
-//@menu
-//* Scheduler Functions::
-//* Scheduler Vars and Data Types::
-//* Some convenient macros::
-//* Index::
-//@end menu
+#ifndef SCHEDULE_H
+#define SCHEDULE_H
-//@node Scheduler Functions, Scheduler Vars and Data Types
-//@subsection Scheduler Functions
+#include "OSThreads.h"
+#include "Capability.h"
-//@cindex initScheduler
-//@cindex exitScheduler
-//@cindex startTasks
-/* initScheduler(), exitScheduler(), startTasks()
- *
+/* initScheduler(), exitScheduler()
* Called from STG : no
* Locks assumed : none
*/
-void initScheduler( void );
-void exitScheduler( void );
-#ifdef SMP
-void startTasks( void );
-#endif
+void initScheduler (void);
+void exitScheduler (void);
+// Place a new thread on the run queue of the specified Capability
+void scheduleThread (Capability *cap, StgTSO *tso);
-//@cindex awakenBlockedQueue
/* awakenBlockedQueue()
*
* Takes a pointer to the beginning of a blocked TSO queue, and
* wakes up the entire queue.
- *
* Called from STG : yes
* Locks assumed : none
*/
#elif defined(PAR)
void awakenBlockedQueue(StgBlockingQueueElement *q, StgClosure *node);
#else
-void awakenBlockedQueue(StgTSO *tso);
+void awakenBlockedQueue (Capability *cap, StgTSO *tso);
#endif
-//@cindex unblockOne
/* unblockOne()
*
- * Takes a pointer to the beginning of a blocked TSO queue, and
- * removes the first thread, placing it on the runnable queue.
- *
- * Called from STG : yes
- * Locks assumed : none
+ * Put the specified thread on the run queue of the given Capability.
+ * Called from STG : yes
+ * Locks assumed : we own the Capability.
*/
-#if defined(GRAN) || defined(PAR)
-StgBlockingQueueElement *unblockOne(StgBlockingQueueElement *bqe, StgClosure *node);
-#else
-StgTSO *unblockOne(StgTSO *tso);
-#endif
+StgTSO * unblockOne(Capability *cap, StgTSO *tso);
-//@cindex raiseAsync
/* raiseAsync()
*
* Raises an exception asynchronously in the specified thread.
* Called from STG : yes
* Locks assumed : none
*/
-void raiseAsync(StgTSO *tso, StgClosure *exception);
+void raiseAsync(Capability *cap, StgTSO *tso, StgClosure *exception);
-//@cindex awaitEvent
-/* awaitEvent()
+/* suspendComputation()
*
- * Raises an exception asynchronously in the specified thread.
+ * A variant of raiseAsync(), this strips the stack of the specified
+ * thread down to the stop_here point, leaving a current closure on
+ * top of the stack at [stop_here - 1].
+ */
+void suspendComputation(Capability *cap, StgTSO *tso, StgPtr stop_here);
+
+/* raiseExceptionHelper */
+StgWord raiseExceptionHelper (StgRegTable *reg, StgTSO *tso, StgClosure *exception);
+
+/* findRetryFrameHelper */
+StgWord findRetryFrameHelper (StgTSO *tso);
+
+/* GetRoots(evac_fn f)
+ *
+ * Call f() for each root known to the scheduler.
*
* Called from STG : NO
- * Locks assumed : sched_mutex
+ * Locks assumed : ????
*/
-void awaitEvent(rtsBool wait); /* In Select.c */
+void GetRoots(evac_fn);
+
+/* workerStart()
+ *
+ * Entry point for a new worker task.
+ * Called from STG : NO
+ * Locks assumed : none
+ */
+void workerStart(Task *task);
-// ToDo: check whether all fcts below are used in the SMP version, too
-//@cindex awaken_blocked_queue
#if defined(GRAN)
void awaken_blocked_queue(StgBlockingQueueElement *q, StgClosure *node);
void unlink_from_bq(StgTSO* tso, StgClosure* node);
void initThread(StgTSO *tso, nat stack_size);
#endif
-//@node Scheduler Vars and Data Types, Some convenient macros, Scheduler Functions
-//@subsection Scheduler Vars and Data Types
-
-//@cindex context_switch
/* Context switch flag.
- * Locks required : sched_mutex
+ * Locks required : none (conflicts are harmless)
*/
-extern nat context_switch;
-extern rtsBool interrupted;
+extern int RTS_VAR(context_switch);
-extern nat ticks_since_select;
-
-//@cindex Capability
-/* Capability type
+/* The state of the scheduler. This is used to control the sequence
+ * of events during shutdown, and when the runtime is interrupted
+ * using ^C.
*/
-typedef StgRegTable Capability;
+#define SCHED_RUNNING 0 /* running as normal */
+#define SCHED_INTERRUPTING 1 /* ^C detected, before threads are deleted */
+#define SCHED_INTERRUPTED 2 /* ^C detected, after threads deleted */
+#define SCHED_SHUTTING_DOWN 3 /* final shutdown */
+
+extern rtsBool RTS_VAR(sched_state);
-/* Free capability list.
- * Locks required: sched_mutex.
+/*
+ * flag that tracks whether we have done any execution in this time slice.
*/
-#ifdef SMP
-extern Capability *free_capabilities;
-extern nat n_free_capabilities;
-#else
-extern Capability MainRegTable;
-#endif
+#define ACTIVITY_YES 0 /* there has been activity in the current slice */
+#define ACTIVITY_MAYBE_NO 1 /* no activity in the current slice */
+#define ACTIVITY_INACTIVE 2 /* a complete slice has passed with no activity */
+#define ACTIVITY_DONE_GC 3 /* like 2, but we've done a GC too */
+
+/* Recent activity flag.
+ * Locks required : Transition from MAYBE_NO to INACTIVE
+ * happens in the timer signal, so it is atomic. Trnasition from
+ * INACTIVE to DONE_GC happens under sched_mutex. No lock required
+ * to set it to ACTIVITY_YES.
+ */
+extern nat recent_activity;
/* Thread queues.
* Locks required : sched_mutex
#if defined(GRAN)
// run_queue_hds defined in GranSim.h
#else
-extern StgTSO *run_queue_hd, *run_queue_tl;
-extern StgTSO *blocked_queue_hd, *blocked_queue_tl;
+extern StgTSO *RTS_VAR(blackhole_queue);
+#if !defined(THREADED_RTS)
+extern StgTSO *RTS_VAR(blocked_queue_hd), *RTS_VAR(blocked_queue_tl);
+extern StgTSO *RTS_VAR(sleeping_queue);
#endif
-/* Linked list of all threads. */
-extern StgTSO *all_threads;
-
-#ifdef SMP
-//@cindex sched_mutex
-//@cindex thread_ready_cond
-//@cindex gc_pending_cond
-extern pthread_mutex_t sched_mutex;
-extern pthread_cond_t thread_ready_cond;
-extern pthread_cond_t gc_pending_cond;
#endif
-//@cindex task_info
-#ifdef SMP
-typedef struct {
- pthread_t id;
- double elapsedtimestart;
- double mut_time;
- double mut_etime;
- double gc_time;
- double gc_etime;
-} task_info;
-
-extern task_info *task_ids;
+/* Linked list of all threads.
+ * Locks required : sched_mutex
+ */
+extern StgTSO *RTS_VAR(all_threads);
+
+/* Set to rtsTrue if there are threads on the blackhole_queue, and
+ * it is possible that one or more of them may be available to run.
+ * This flag is set to rtsFalse after we've checked the queue, and
+ * set to rtsTrue just before we run some Haskell code. It is used
+ * to decide whether we should yield the Capability or not.
+ * Locks required : none (see scheduleCheckBlackHoles()).
+ */
+extern rtsBool blackholes_need_checking;
+
+#if defined(THREADED_RTS)
+extern Mutex RTS_VAR(sched_mutex);
#endif
-/* Needed by Hugs.
- */
-void interruptStgRts ( void );
+StgBool isThreadBound(StgTSO *tso);
+
+SchedulerStatus rts_mainLazyIO(HaskellObj p, /*out*/HaskellObj *ret);
-void raiseAsync(StgTSO *tso, StgClosure *exception);
-nat run_queue_len(void);
+/* Called by shutdown_handler(). */
+void interruptStgRts (void);
-void resurrectThreads( StgTSO * );
+nat run_queue_len (void);
-//@node Some convenient macros, Index, Scheduler Vars and Data Types
-//@subsection Some convenient macros
+void resurrectThreads (StgTSO *);
+
+void printAllThreads(void);
/* debugging only
*/
#ifdef DEBUG
-void printThreadBlockage(StgTSO *tso);
-void printThreadStatus(StgTSO *tso);
-void printAllThreads(void);
-#endif
void print_bq (StgClosure *node);
+#endif
+#if defined(PAR)
+void print_bqe (StgBlockingQueueElement *bqe);
+#endif
+
+void labelThread(StgPtr tso, char *label);
/* -----------------------------------------------------------------------------
- * Some convenient macros...
+ * Some convenient macros/inline functions...
*/
-/* this is the NIL ptr for a TSO queue (e.g. runnable queue) */
-#define END_TSO_QUEUE ((StgTSO *)(void*)&END_TSO_QUEUE_closure)
-/* this is the NIL ptr for a list CAFs */
-#define END_ECAF_LIST ((StgCAF *)(void*)&END_TSO_QUEUE_closure)
-#if defined(PAR) || defined(GRAN)
-/* this is the NIL ptr for a blocking queue */
-# define END_BQ_QUEUE ((StgBlockingQueueElement *)(void*)&END_TSO_QUEUE_closure)
-/* this is the NIL ptr for a blocked fetch queue (as in PendingFetches in GUM) */
-# define END_BF_QUEUE ((StgBlockedFetch *)(void*)&END_TSO_QUEUE_closure)
-#endif
+#if !IN_STG_CODE
+
+/* END_TSO_QUEUE and friends now defined in includes/StgMiscClosures.h */
-//@cindex APPEND_TO_RUN_QUEUE
/* Add a thread to the end of the run queue.
* NOTE: tso->link should be END_TSO_QUEUE before calling this macro.
+ * ASSUMES: cap->running_task is the current task.
*/
-#define APPEND_TO_RUN_QUEUE(tso) \
- ASSERT(tso->link == END_TSO_QUEUE); \
- if (run_queue_hd == END_TSO_QUEUE) { \
- run_queue_hd = tso; \
- } else { \
- run_queue_tl->link = tso; \
- } \
- run_queue_tl = tso;
-
-//@cindex PUSH_ON_RUN_QUEUE
+STATIC_INLINE void
+appendToRunQueue (Capability *cap, StgTSO *tso)
+{
+ ASSERT(tso->link == END_TSO_QUEUE);
+ if (cap->run_queue_hd == END_TSO_QUEUE) {
+ cap->run_queue_hd = tso;
+ } else {
+ cap->run_queue_tl->link = tso;
+ }
+ cap->run_queue_tl = tso;
+}
+
/* Push a thread on the beginning of the run queue. Used for
* newly awakened threads, so they get run as soon as possible.
+ * ASSUMES: cap->running_task is the current task.
*/
-#define PUSH_ON_RUN_QUEUE(tso) \
- tso->link = run_queue_hd; \
- run_queue_hd = tso; \
- if (run_queue_tl == END_TSO_QUEUE) { \
- run_queue_tl = tso; \
+STATIC_INLINE void
+pushOnRunQueue (Capability *cap, StgTSO *tso)
+{
+ tso->link = cap->run_queue_hd;
+ cap->run_queue_hd = tso;
+ if (cap->run_queue_tl == END_TSO_QUEUE) {
+ cap->run_queue_tl = tso;
}
+}
-//@cindex POP_RUN_QUEUE
/* Pop the first thread off the runnable queue.
*/
-#define POP_RUN_QUEUE() \
- ({ StgTSO *t = run_queue_hd; \
- if (t != END_TSO_QUEUE) { \
- run_queue_hd = t->link; \
- t->link = END_TSO_QUEUE; \
- if (run_queue_hd == END_TSO_QUEUE) { \
- run_queue_tl = END_TSO_QUEUE; \
- } \
- } \
- t; \
- })
-
-//@cindex APPEND_TO_BLOCKED_QUEUE
+STATIC_INLINE StgTSO *
+popRunQueue (Capability *cap)
+{
+ StgTSO *t = cap->run_queue_hd;
+ ASSERT(t != END_TSO_QUEUE);
+ cap->run_queue_hd = t->link;
+ t->link = END_TSO_QUEUE;
+ if (cap->run_queue_hd == END_TSO_QUEUE) {
+ cap->run_queue_tl = END_TSO_QUEUE;
+ }
+ return t;
+}
+
/* Add a thread to the end of the blocked queue.
*/
-#define APPEND_TO_BLOCKED_QUEUE(tso) \
- ASSERT(tso->link == END_TSO_QUEUE); \
- if (blocked_queue_hd == END_TSO_QUEUE) { \
- blocked_queue_hd = tso; \
- } else { \
- blocked_queue_tl->link = tso; \
- } \
+#if !defined(THREADED_RTS)
+STATIC_INLINE void
+appendToBlockedQueue(StgTSO *tso)
+{
+ ASSERT(tso->link == END_TSO_QUEUE);
+ if (blocked_queue_hd == END_TSO_QUEUE) {
+ blocked_queue_hd = tso;
+ } else {
+ blocked_queue_tl->link = tso;
+ }
blocked_queue_tl = tso;
+}
+#endif
-//@cindex THREAD_RUNNABLE
-/* Signal that a runnable thread has become available, in
- * case there are any waiting tasks to execute it.
+/* Check whether various thread queues are empty
*/
-#ifdef SMP
-#define THREAD_RUNNABLE() \
- if (free_capabilities != NULL) { \
- pthread_cond_signal(&thread_ready_cond); \
- } \
- context_switch = 1;
-#else
-#define THREAD_RUNNABLE() /* nothing */
+STATIC_INLINE rtsBool
+emptyQueue (StgTSO *q)
+{
+ return (q == END_TSO_QUEUE);
+}
+
+STATIC_INLINE rtsBool
+emptyRunQueue(Capability *cap)
+{
+ return emptyQueue(cap->run_queue_hd);
+}
+
+#if !defined(THREADED_RTS)
+#define EMPTY_BLOCKED_QUEUE() (emptyQueue(blocked_queue_hd))
+#define EMPTY_SLEEPING_QUEUE() (emptyQueue(sleeping_queue))
+#endif
+
+STATIC_INLINE rtsBool
+emptyThreadQueues(Capability *cap)
+{
+ return emptyRunQueue(cap)
+#if !defined(THREADED_RTS)
+ && EMPTY_BLOCKED_QUEUE() && EMPTY_SLEEPING_QUEUE()
+#endif
+ ;
+}
+
+#ifdef DEBUG
+void sched_belch(char *s, ...)
+ GNU_ATTRIBUTE(format (printf, 1, 2));
#endif
-//@node Index, , Some convenient macros
-//@subsection Index
-
-//@index
-//* APPEND_TO_BLOCKED_QUEUE:: @cindex\s-+APPEND_TO_BLOCKED_QUEUE
-//* APPEND_TO_RUN_QUEUE:: @cindex\s-+APPEND_TO_RUN_QUEUE
-//* Capability:: @cindex\s-+Capability
-//* POP_RUN_QUEUE :: @cindex\s-+POP_RUN_QUEUE
-//* PUSH_ON_RUN_QUEUE:: @cindex\s-+PUSH_ON_RUN_QUEUE
-//* THREAD_RUNNABLE:: @cindex\s-+THREAD_RUNNABLE
-//* awaitEvent:: @cindex\s-+awaitEvent
-//* awakenBlockedQueue:: @cindex\s-+awakenBlockedQueue
-//* awaken_blocked_queue:: @cindex\s-+awaken_blocked_queue
-//* context_switch:: @cindex\s-+context_switch
-//* exitScheduler:: @cindex\s-+exitScheduler
-//* gc_pending_cond:: @cindex\s-+gc_pending_cond
-//* initScheduler:: @cindex\s-+initScheduler
-//* raiseAsync:: @cindex\s-+raiseAsync
-//* sched_mutex:: @cindex\s-+sched_mutex
-//* startTasks:: @cindex\s-+startTasks
-//* task_info:: @cindex\s-+task_info
-//* thread_ready_cond:: @cindex\s-+thread_ready_cond
-//* unblockOne:: @cindex\s-+unblockOne
-//@end index
+#endif /* !IN_STG_CODE */
+
+STATIC_INLINE void
+dirtyTSO (StgTSO *tso)
+{
+ tso->flags |= TSO_DIRTY;
+}
+
+#endif /* SCHEDULE_H */
+