oops, initialize atomic_modify_mutvar_mutex

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

diff --git a/ghc/rts/Capability.h b/ghc/rts/Capability.h
index b559dcd..50e0b94 100644 (file)
--- a/ghc/rts/Capability.h
+++ b/ghc/rts/Capability.h
@@ -1,19 +1,19 @@
 /* ---------------------------------------------------------------------------
  *
- * (c) The GHC Team, 2001-2003
+ * (c) The GHC Team, 2001-2006
  *
  * Capabilities
  *
  * The notion of a capability is used when operating in multi-threaded
- * environments (which the SMP and Threads builds of the RTS do), to
+ * environments (which the THREADED_RTS build of the RTS does), to
  * hold all the state an OS thread/task needs to run Haskell code:
  * its STG registers, a pointer to its  TSO, a nursery etc. During
  * STG execution, a pointer to the capabilitity is kept in a 
  * register (BaseReg).
  *
- * Only in an SMP build will there be multiple capabilities, the threaded
- * RTS and other non-threaded builds, there is one global capability,
- * namely MainRegTable.
+ * Only in an THREADED_RTS build will there be multiple capabilities,
+ * in the non-threaded builds there is one global capability, namely
+ * MainCapability.
  *
  * This header file contains the functions for working with capabilities.
  * (the main, and only, consumer of this interface is the scheduler).
@@ -60,6 +60,12 @@ struct Capability_ {
     // this list.
     Task *suspended_ccalling_tasks;
 
+    // One mutable list per generation, so we don't need to take any
+    // locks when updating an old-generation thunk.  These
+    // mini-mut-lists are moved onto the respective gen->mut_list at
+    // each GC.
+    bdescr **mut_lists;
+
 #if defined(THREADED_RTS)
     // Worker Tasks waiting in the wings.  Singly-linked.
     Task *spare_workers;
@@ -75,18 +81,37 @@ struct Capability_ {
     Task *returning_tasks_hd; // Singly-linked, with head/tail
     Task *returning_tasks_tl;
 #endif
+
+    // Per-capability STM-related data
+    StgTVarWaitQueue *free_tvar_wait_queues;
+    StgTRecChunk *free_trec_chunks;
+    StgTRecHeader *free_trec_headers;
+    nat transaction_tokens;
 }; // typedef Capability, defined in RtsAPI.h
 
 
+#if defined(THREADED_RTS)
+#define ASSERT_TASK_ID(task) ASSERT(task->id == osThreadId())
+#else
+#define ASSERT_TASK_ID(task) /*empty*/
+#endif
+
 // These properties should be true when a Task is holding a Capability
-#define ASSERT_CAPABILITY_INVARIANTS(cap,task)                         \
+#define ASSERT_FULL_CAPABILITY_INVARIANTS(cap,task)                    \
   ASSERT(cap->running_task != NULL && cap->running_task == task);      \
   ASSERT(task->cap == cap);                                            \
-  ASSERT(cap->run_queue_hd == END_TSO_QUEUE ?                          \
-           cap->run_queue_tl == END_TSO_QUEUE : 1);                    \
-  ASSERT(myTask() == task);                                            \
-  ASSERT(task->id == osThreadId());
-
+  ASSERT_PARTIAL_CAPABILITY_INVARIANTS(cap,task)
+
+// Sometimes a Task holds a Capability, but the Task is not associated
+// with that Capability (ie. task->cap != cap).  This happens when
+// (a) a Task holds multiple Capabilities, and (b) when the current
+// Task is bound, its thread has just blocked, and it may have been
+// moved to another Capability.
+#define ASSERT_PARTIAL_CAPABILITY_INVARIANTS(cap,task) \
+  ASSERT(cap->run_queue_hd == END_TSO_QUEUE ?          \
+           cap->run_queue_tl == END_TSO_QUEUE : 1);    \
+  ASSERT(myTask() == task);                            \
+  ASSERT_TASK_ID(task);
 
 // Converts a *StgRegTable into a *Capability.
 //
@@ -115,8 +140,8 @@ INLINE_HEADER void releaseCapability  (Capability* cap STG_UNUSED) {};
 INLINE_HEADER void releaseCapability_ (Capability* cap STG_UNUSED) {};
 #endif
 
-#if !IN_STG_CODE && !defined(SMP)
-// for non-SMP, we have one global capability
+#if !IN_STG_CODE
+// one global capability
 extern Capability MainCapability; 
 #endif
 
@@ -141,6 +166,8 @@ extern Capability *last_free_capability;
 //
 void waitForReturnCapability (Capability **cap/*in/out*/, Task *task);
 
+INLINE_HEADER void recordMutableCap (StgClosure *p, Capability *cap, nat gen);
+
 #if defined(THREADED_RTS)
 
 // Gives up the current capability IFF there is a higher-priority
@@ -176,6 +203,10 @@ void prodAllCapabilities (void);
 //
 void shutdownCapability (Capability *cap, Task *task);
 
+// Attempt to gain control of a Capability if it is free.
+//
+rtsBool tryGrabCapability (Capability *cap, Task *task);
+
 #else // !THREADED_RTS
 
 // Grab a capability.  (Only in the non-threaded RTS; in the threaded
@@ -185,4 +216,24 @@ extern void grabCapability (Capability **pCap);
 
 #endif /* !THREADED_RTS */
 
+/* -----------------------------------------------------------------------------
+ * INLINE functions... private below here
+ * -------------------------------------------------------------------------- */
+
+INLINE_HEADER void
+recordMutableCap (StgClosure *p, Capability *cap, nat gen)
+{
+    bdescr *bd;
+
+    bd = cap->mut_lists[gen];
+    if (bd->free >= bd->start + BLOCK_SIZE_W) {
+       bdescr *new_bd;
+       new_bd = allocBlock_lock();
+       new_bd->link = bd;
+       bd = new_bd;
+       cap->mut_lists[gen] = bd;
+    }
+    *bd->free++ = (StgWord)p;
+}
+
 #endif /* CAPABILITY_H */