Type synonym families may be nullary

[ghc-hetmet.git] / includes / TSO.h

diff --git a/includes/TSO.h b/includes/TSO.h
index d096d40..be50c12 100644 (file)
--- a/includes/TSO.h
+++ b/includes/TSO.h
@@ -33,16 +33,6 @@ typedef struct {
 } StgTSOStatBuf;
 
 /*
- * GRAN: We distinguish between the various classes of threads in 
- * the system.
- */
-typedef enum {
-  AdvisoryPriority,
-  MandatoryPriority,
-  RevalPriority
-} StgThreadPriority;
-
-/*
  * PROFILING info in a TSO
  */
 typedef struct {
@@ -50,25 +40,6 @@ typedef struct {
 } StgTSOProfInfo;
 
 /*
- * PAR info in a TSO
- */
-typedef StgTSOStatBuf StgTSOParInfo;
-
-/*
- * DIST info in a TSO
- */
-typedef struct {
-  StgThreadPriority  priority;   
-  StgInt             revalTid;   /* ToDo: merge both into 1 word */
-  StgInt             revalSlot;
-} StgTSODistInfo;
-
-/*
- * GRAN info in a TSO
- */
-typedef StgTSOStatBuf StgTSOGranInfo;
-
-/*
  * There is no TICKY info in a TSO at this time.
  */
 
@@ -77,27 +48,6 @@ typedef StgTSOStatBuf StgTSOGranInfo;
  */
 typedef StgWord32 StgThreadID;
 
-/* 
- * Flags for the tso->flags field.
- *
- * The TSO_DIRTY flag indicates that this TSO's stack should be
- * scanned during garbage collection.  The link field of a TSO is
- * always scanned, so we don't have to dirty a TSO just for linking
- * it on a different list.
- *
- * TSO_DIRTY is set by 
- *    - schedule(), just before running a thread,
- *    - raiseAsync(), because it modifies a thread's stack
- *    - resumeThread(), just before running the thread again
- * and unset by the garbage collector (only).
- */
-#define TSO_DIRTY   1
-
-/*
- * TSO_LOCKED is set when a TSO is locked to a particular Capability.
- */
-#define TSO_LOCKED  2
-
 #define tsoDirty(tso)  ((tso)->flags & TSO_DIRTY)
 #define tsoLocked(tso) ((tso)->flags & TSO_LOCKED)
 
@@ -127,6 +77,7 @@ typedef union {
   StgWord target;
 } StgTSOBlockInfo;
 
+
 /*
  * TSOs live on the heap, and therefore look just like heap objects.
  * Large TSOs will live in their own "block group" allocated by the
@@ -144,34 +95,48 @@ typedef union {
 typedef struct StgTSO_ {
     StgHeader               header;
 
-    struct StgTSO_*         link;       /* Links threads onto blocking queues */
+    /* The link field, for linking threads together in lists (e.g. the
+       run queue on a Capability.
+    */
+    struct StgTSO_*         _link;
+    /*
+       NOTE!!!  do not modify _link directly, it is subject to
+       a write barrier for generational GC.  Instead use the
+       setTSOLink() function.  Exceptions to this rule are:
+
+       * setting the link field to END_TSO_QUEUE
+       * putting a TSO on the blackhole_queue
+       * setting the link field of the currently running TSO, as it
+         will already be dirty.
+    */
+
     struct StgTSO_*         global_link;    /* Links all threads together */
     
     StgWord16               what_next;      /* Values defined in Constants.h */
     StgWord16               why_blocked;    /* Values defined in Constants.h */
     StgWord32               flags;
     StgTSOBlockInfo         block_info;
-    struct StgTSO_*         blocked_exceptions;
     StgThreadID             id;
     int                     saved_errno;
     struct Task_*           bound;
     struct Capability_*     cap;
     struct StgTRecHeader_ * trec;       /* STM transaction record */
 
+    /* 
+       A list of threads blocked on this TSO waiting to throw
+       exceptions.  In order to access this field, the TSO must be
+       locked using lockClosure/unlockClosure (see SMP.h).
+    */
+    struct StgTSO_ *        blocked_exceptions;
+
 #ifdef TICKY_TICKY
     /* TICKY-specific stuff would go here. */
 #endif
 #ifdef PROFILING
     StgTSOProfInfo prof;
 #endif
-#ifdef PAR
-    StgTSOParInfo par;
-#endif
-#ifdef GRAN
-    StgTSOGranInfo gran;
-#endif
-#ifdef DIST
-    StgTSODistInfo dist;
+#ifdef mingw32_HOST_OS
+    StgWord32 saved_winerror;
 #endif
 
     /* The thread stack... */
@@ -183,6 +148,13 @@ typedef struct StgTSO_ {
 } StgTSO;
 
 /* -----------------------------------------------------------------------------
+   functions
+   -------------------------------------------------------------------------- */
+
+extern void dirty_TSO  (Capability *cap, StgTSO *tso);
+extern void setTSOLink (Capability *cap, StgTSO *tso, StgTSO *target);
+
+/* -----------------------------------------------------------------------------
    Invariants:
 
    An active thread has the following properties:
@@ -229,16 +201,6 @@ typedef struct StgTSO_ {
       (tso->sp is left pointing at the top word on the stack so that
       the return value or exception will be retained by a GC).
 
-   tso->blocked_exceptions is either:
-
-      NULL             if async exceptions are unblocked.
-
-      END_TSO_QUEUE    if async exceptions are blocked, but no threads
-                       are currently waiting to deliver.
-
-      (StgTSO *)tso    if threads are currently awaiting delivery of
-                       exceptions to this thread.
-
    The 2 cases BlockedOnGA and BlockedOnGA_NoSend are needed in a GUM
    setup only. They mark a TSO that has entered a FETCH_ME or
    FETCH_ME_BQ closure, respectively; only the first TSO hitting the 
@@ -260,20 +222,7 @@ extern StgTSO dummy_tso;
 
 #define TSO_STRUCT_SIZEW (TSO_STRUCT_SIZE / sizeof(W_))
 
-
 /* this is the NIL ptr for a TSO queue (e.g. runnable queue) */
-#if IN_STG_CODE
-#define END_TSO_QUEUE  (stg_END_TSO_QUEUE_closure)
-#else
 #define END_TSO_QUEUE  ((StgTSO *)(void*)&stg_END_TSO_QUEUE_closure)
-#endif
-
-#if defined(PAR) || defined(GRAN)
-/* this is the NIL ptr for a blocking queue */
-# define END_BQ_QUEUE  ((StgBlockingQueueElement *)(void*)&stg_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*)&stg_END_TSO_QUEUE_closure)
-#endif
-/* ToDo?: different name for end of sleeping queue ? -- HWL */
 
 #endif /* TSO_H */