[project @ 2003-10-01 10:49:07 by wolfgang]

[ghc-hetmet.git] / ghc / rts / Schedule.h

diff --git a/ghc/rts/Schedule.h b/ghc/rts/Schedule.h
index 376698e..ebbe7d1 100644 (file)
--- a/ghc/rts/Schedule.h
+++ b/ghc/rts/Schedule.h
@@ -1,5 +1,5 @@
 /* -----------------------------------------------------------------------------
- * $Id: Schedule.h,v 1.32 2002/04/10 11:43:46 stolz Exp $
+ * $Id: Schedule.h,v 1.40 2003/10/01 10:49:09 wolfgang Exp $
  *
  * (c) The GHC Team 1998-1999
  *
@@ -34,6 +34,9 @@ void awakenBlockedQueue(StgBlockingQueueElement *q, StgClosure *node);
 void awakenBlockedQueue(StgBlockingQueueElement *q, StgClosure *node);
 #else
 void awakenBlockedQueue(StgTSO *tso);
+#if defined(RTS_SUPPORTS_THREADS)
+void awakenBlockedQueueNoLock(StgTSO *tso);
+#endif
 #endif
 
 /* unblockOne()
@@ -58,10 +61,11 @@ StgTSO *unblockOne(StgTSO *tso);
  * Locks assumed   :  none
  */
 void raiseAsync(StgTSO *tso, StgClosure *exception);
+void raiseAsyncWithLock(StgTSO *tso, StgClosure *exception);
 
-/* awaitEvent()
+/* awaitEvent(rtsBool wait)
  *
- * Raises an exception asynchronously in the specified thread.
+ * Checks for blocked threads that need to be woken.
  *
  * Called from STG :  NO
  * Locks assumed   :  sched_mutex
@@ -77,6 +81,16 @@ void awaitEvent(rtsBool wait);  /* In Select.c */
  */
 rtsBool wakeUpSleepingThreads(nat);  /* In Select.c */
 
+/* wakeBlockedWorkerThread()
+ *
+ * If a worker thread is currently blocked in awaitEvent(), interrupt it.
+ *
+ * Called from STG :  NO
+ * Locks assumed   :  sched_mutex
+ */
+void wakeBlockedWorkerThread(void); /* In Select.c */
+
+
 /* GetRoots(evac_fn f)
  *
  * Call f() for each root known to the scheduler.
@@ -135,17 +149,11 @@ extern nat         rts_n_waiting_workers;
 extern nat         rts_n_waiting_tasks;
 #endif
 
+StgBool rtsSupportsBoundThreads(void);
+StgBool isThreadBound(StgTSO *tso);
 StgInt forkProcess(StgTSO *tso);
 
-/* Sigh, RTS-internal versions of waitThread(), scheduleThread(), and
-   rts_evalIO() for the use by main() only. ToDo: better. */
-extern SchedulerStatus waitThread_(StgTSO *tso,
-                                  /*out*/StgClosure **ret
-#if defined(THREADED_RTS)
-                                  , rtsBool blockWaiting
-#endif
-                                  );
-extern SchedulerStatus rts_mainEvalIO(HaskellObj p, /*out*/HaskellObj *ret);
+extern SchedulerStatus rts_mainLazyIO(HaskellObj p, /*out*/HaskellObj *ret);
 
 
 /* Called by shutdown_handler(). */
@@ -160,11 +168,13 @@ void resurrectThreads( StgTSO * );
  *
  * These are the threads which clients have requested that we run.  
  *
- * In a 'threaded' build, we might have several concurrent clients all
- * waiting for results, and each one will wait on a condition variable
- * until the result is available.
+ * In a 'threaded' build, each of these corresponds to one bound thread.
+ * The pointer to the StgMainThread is passed as a parameter to schedule;
+ * this invocation of schedule will always pass this main thread's
+ * bound_thread_cond to waitForkWorkCapability; OS-thread-switching
+ * takes place using passCapability.
  *
- * In non-SMP, clients are strictly nested: the first client calls
+ * In non-threaded builds, clients are strictly nested: the first client calls
  * into the RTS, which might call out again to C with a _ccall_GC, and
  * eventually re-enter the RTS.
  *
@@ -180,8 +190,12 @@ typedef struct StgMainThread_ {
   SchedulerStatus  stat;
   StgClosure **    ret;
 #if defined(RTS_SUPPORTS_THREADS)
+#if defined(THREADED_RTS)
+  Condition        bound_thread_cond;
+#else
   Condition        wakeup;
 #endif
+#endif
   struct StgMainThread_ *link;
 } StgMainThread;
 
@@ -190,18 +204,22 @@ typedef struct StgMainThread_ {
  */
 extern StgMainThread *main_threads;
 
+void printAllThreads(void);
+#ifdef COMPILING_SCHEDULER
+static void printThreadBlockage(StgTSO *tso);
+static void printThreadStatus(StgTSO *tso);
+#endif
 /* 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...
  */
@@ -260,9 +278,7 @@ void print_bqe (StgBlockingQueueElement *bqe);
  */
 #if defined(RTS_SUPPORTS_THREADS)
 #define THREAD_RUNNABLE()                      \
-  if ( !noCapabilities() ) {                   \
-     signalCondition(&thread_ready_cond);      \
-  }                                            \
+  wakeBlockedWorkerThread();                   \
   context_switch = 1;
 #else
 #define THREAD_RUNNABLE()  /* nothing */
@@ -280,4 +296,14 @@ void print_bqe (StgBlockingQueueElement *bqe);
                                EMPTY_BLOCKED_QUEUE() && \
                                EMPTY_SLEEPING_QUEUE())
 
+#if defined(RTS_SUPPORTS_THREADS)
+/* If no task is waiting for a capability,
+ * and if there is work to be done
+ * or if we need to wait for IO or delay requests,
+ * spawn a new worker thread.
+ */
+void
+startSchedulerTaskIfNecessary(void);
+#endif
+
 #endif /* __SCHEDULE_H__ */