Move the freeing of Capabilities later in the shutdown sequence

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

diff --git a/rts/Capability.h b/rts/Capability.h
index dedd635..9446a7e 100644 (file)
--- a/rts/Capability.h
+++ b/rts/Capability.h
@@ -25,6 +25,7 @@
 
 #include "RtsFlags.h"
 #include "Task.h"
+#include "Sparks.h"
 
 struct Capability_ {
     // State required by the STG virtual machine when running Haskell
@@ -66,6 +67,10 @@ struct Capability_ {
     // each GC.
     bdescr **mut_lists;
 
+    // Context switch flag. We used to have one global flag, now one 
+    // per capability. Locks required  : none (conflicts are harmless)
+    int context_switch;
+
 #if defined(THREADED_RTS)
     // Worker Tasks waiting in the wings.  Singly-linked.
     Task *spare_workers;
@@ -86,6 +91,13 @@ struct Capability_ {
     // woken up by another Capability.
     StgTSO *wakeup_queue_hd;
     StgTSO *wakeup_queue_tl;
+
+    SparkPool *sparks;
+
+    // Stats on spark creation/conversion
+    nat sparks_created;
+    nat sparks_converted;
+    nat sparks_pruned;
 #endif
 
     // Per-capability STM-related data
@@ -94,7 +106,10 @@ struct Capability_ {
     StgTRecChunk *free_trec_chunks;
     StgTRecHeader *free_trec_headers;
     nat transaction_tokens;
-}; // typedef Capability, defined in RtsAPI.h
+} // typedef Capability is defined in RtsAPI.h
+  // Capabilities are stored in an array, so make sure that adjacent
+  // Capabilities don't share any cache-lines:
+  ATTRIBUTE_ALIGNED(64);
 
 
 #if defined(THREADED_RTS)
@@ -139,12 +154,16 @@ void initCapabilities (void);
 // ASSUMES: cap->running_task is the current Task.
 //
 #if defined(THREADED_RTS)
-void releaseCapability  (Capability* cap);
-void releaseCapability_ (Capability* cap); // assumes cap->lock is held
+void releaseCapability           (Capability* cap);
+void releaseAndWakeupCapability  (Capability* cap);
+void releaseCapability_ (Capability* cap, rtsBool always_wakeup); 
+// assumes cap->lock is held
 #else
 // releaseCapability() is empty in non-threaded RTS
 INLINE_HEADER void releaseCapability  (Capability* cap STG_UNUSED) {};
-INLINE_HEADER void releaseCapability_ (Capability* cap STG_UNUSED) {};
+INLINE_HEADER void releaseAndWakeupCapability  (Capability* cap STG_UNUSED) {};
+INLINE_HEADER void releaseCapability_ (Capability* cap STG_UNUSED, 
+                                       rtsBool always_wakeup STG_UNUSED) {};
 #endif
 
 #if !IN_STG_CODE
@@ -162,6 +181,9 @@ extern Capability *capabilities;
 //
 extern Capability *last_free_capability;
 
+// GC indicator, in scope for the scheduler
+extern volatile StgWord waiting_for_gc;
+
 // Acquires a capability at a return point.  If *cap is non-NULL, then
 // this is taken as a preference for the Capability we wish to
 // acquire.
@@ -199,11 +221,8 @@ void waitForCapability (Task *task, Mutex *mutex, Capability **pCap);
 // Wakes up a thread on a Capability (probably a different Capability
 // from the one held by the current Task).
 //
-void wakeupThreadOnCapability (Capability *cap, StgTSO *tso);
-void wakeupThreadOnCapability_lock (Capability *cap, StgTSO *tso);
-
-void migrateThreadToCapability (Capability *cap, StgTSO *tso);
-void migrateThreadToCapability_lock (Capability *cap, StgTSO *tso);
+void wakeupThreadOnCapability (Capability *my_cap, Capability *other_cap,
+                               StgTSO *tso);
 
 // Wakes up a worker thread on just one Capability, used when we
 // need to service some global event.
@@ -217,12 +236,20 @@ void prodAllCapabilities (void);
 // Waits for a capability to drain of runnable threads and workers,
 // and then acquires it.  Used at shutdown time.
 //
-void shutdownCapability (Capability *cap, Task *task);
+void shutdownCapability (Capability *cap, Task *task, rtsBool wait_foreign);
 
 // Attempt to gain control of a Capability if it is free.
 //
 rtsBool tryGrabCapability (Capability *cap, Task *task);
 
+// Try to steal a spark from other Capabilities
+//
+rtsBool stealWork (Capability *cap);
+
+INLINE_HEADER rtsBool emptySparkPoolCap (Capability *cap);
+INLINE_HEADER nat     sparkPoolSizeCap  (Capability *cap);
+INLINE_HEADER void    discardSparksCap  (Capability *cap);
+
 #else // !THREADED_RTS
 
 // Grab a capability.  (Only in the non-threaded RTS; in the threaded
@@ -232,8 +259,17 @@ extern void grabCapability (Capability **pCap);
 
 #endif /* !THREADED_RTS */
 
-// Free a capability on exit
-void freeCapability (Capability *cap);
+// cause all capabilities to context switch as soon as possible.
+void setContextSwitches(void);
+
+// Free all capabilities
+void freeCapabilities (void);
+
+// FOr the GC:
+void markSomeCapabilities (evac_fn evac, void *user, nat i0, nat delta, 
+                           rtsBool prune_sparks);
+void markCapabilities (evac_fn evac, void *user);
+void traverseSparkQueues (evac_fn evac, void *user);
 
 /* -----------------------------------------------------------------------------
  * INLINE functions... private below here
@@ -244,6 +280,8 @@ recordMutableCap (StgClosure *p, Capability *cap, nat gen)
 {
     bdescr *bd;
 
+    // We must own this Capability in order to modify its mutable list.
+    ASSERT(cap->running_task == myTask());
     bd = cap->mut_lists[gen];
     if (bd->free >= bd->start + BLOCK_SIZE_W) {
        bdescr *new_bd;
@@ -255,4 +293,18 @@ recordMutableCap (StgClosure *p, Capability *cap, nat gen)
     *bd->free++ = (StgWord)p;
 }
 
+#if defined(THREADED_RTS)
+INLINE_HEADER rtsBool
+emptySparkPoolCap (Capability *cap) 
+{ return looksEmpty(cap->sparks); }
+
+INLINE_HEADER nat
+sparkPoolSizeCap (Capability *cap) 
+{ return sparkPoolSize(cap->sparks); }
+
+INLINE_HEADER void
+discardSparksCap (Capability *cap) 
+{ return discardSparks(cap->sparks); }
+#endif
+
 #endif /* CAPABILITY_H */