X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;ds=sidebyside;f=ghc%2Frts%2FCapability.h;h=50e0b9400d4531506656889cfc0c51867a269ca8;hb=25cc1d1f2d9bf9a83725e49884bd83ab35000e3e;hp=2a04e41e6ba69b11f07c36052de1d568e45377f2;hpb=afd08a9c06ae4b15e33e26e5a2818801c7fee429;p=ghc-hetmet.git

diff --git a/ghc/rts/Capability.h b/ghc/rts/Capability.h
index 2a04e41..50e0b94 100644
--- 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).
@@ -97,12 +97,20 @@ struct Capability_ {
 #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_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.
@@ -132,8 +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