X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=rts%2Fsm%2FEvac.c;h=c40d18b29549a96118fa2e2400b7c2db3725ef13;hb=91a5df02a15c0a06b1d4a36a569e41b0624a1185;hp=6325a12f9ce8f9707b7246abe8012d25d4daf993;hpb=30554cc82c2aeec64b03495048a650a3c0443d3c;p=ghc-hetmet.git

diff --git a/rts/sm/Evac.c b/rts/sm/Evac.c
index 6325a12..c40d18b 100644
--- a/rts/sm/Evac.c
+++ b/rts/sm/Evac.c
@@ -11,20 +11,21 @@
  *
  * ---------------------------------------------------------------------------*/
 
+#include "PosixSource.h"
 #include "Rts.h"
-#include "Storage.h"
-#include "MBlock.h"
+
 #include "Evac.h"
+#include "Storage.h"
 #include "GC.h"
 #include "GCThread.h"
 #include "GCUtils.h"
 #include "Compact.h"
 #include "Prelude.h"
-#include "LdvProfile.h"
 #include "Trace.h"
+#include "LdvProfile.h"
 
 #if defined(PROF_SPIN) && defined(THREADED_RTS) && defined(PARALLEL_GC)
-StgWord64 whitehole_spin = 0;
+StgWord64 evac_collision = 0;
 #endif
 
 #if defined(THREADED_RTS) && !defined(PARALLEL_GC)
@@ -74,10 +75,10 @@ alloc_for_copy (nat size, step *stp)
      * necessary.
      */
     to = ws->todo_free;
-    if (to + size > ws->todo_lim) {
+    ws->todo_free += size;
+    if (ws->todo_free > ws->todo_lim) {
 	to = todo_block_full(size, ws);
     }
-    ws->todo_free = to + size;
     ASSERT(ws->todo_free >= ws->todo_bd->free && ws->todo_free <= ws->todo_lim);
 
     return to;
@@ -111,9 +112,13 @@ copy_tag(StgClosure **p, const StgInfoTable *info,
 #if defined(PARALLEL_GC)
     {
         const StgInfoTable *new_info;
-        new_info = (const StgInfoTable *)cas((StgPtr)&src->header.info, (W_)info, MK_FORWARDING_PTR(to));
+        new_info = (const StgInfoTable *)cas((StgPtr)&src->header.info,
+                                             (W_)info, MK_FORWARDING_PTR(to));
         if (new_info != info) {
-            return evacuate(p); // does the failed_to_evac stuff
+#if defined(PROF_SPIN)
+            evac_collision++;
+#endif
+            evacuate(p); // does the failed_to_evac stuff
         } else {
             *p = TAG_CLOSURE(tag,(StgClosure*)to);
         }
@@ -167,46 +172,42 @@ copy_tag_nolock(StgClosure **p, const StgInfoTable *info,
  * used to optimise evacuation of BLACKHOLEs.
  */
 static rtsBool
-copyPart(StgClosure **p, StgClosure *src, nat size_to_reserve, nat size_to_copy, step *stp)
+copyPart(StgClosure **p, const StgInfoTable *info, StgClosure *src, 
+         nat size_to_reserve, nat size_to_copy, step *stp)
 {
     StgPtr to, from;
     nat i;
-    StgWord info;
     
-#if defined(PARALLEL_GC)
-spin:
-	info = xchg((StgPtr)&src->header.info, (W_)&stg_WHITEHOLE_info);
-	if (info == (W_)&stg_WHITEHOLE_info) {
-#ifdef PROF_SPIN
-	    whitehole_spin++;
-#endif
-	    goto spin;
-	}
-    if (IS_FORWARDING_PTR(info)) {
-	src->header.info = (const StgInfoTable *)info;
-	evacuate(p); // does the failed_to_evac stuff
-	return rtsFalse;
-    }
-#else
-    info = (W_)src->header.info;
-#endif
-
     to = alloc_for_copy(size_to_reserve, stp);
-    *p = (StgClosure *)to;
 
     TICK_GC_WORDS_COPIED(size_to_copy);
 
     from = (StgPtr)src;
-    to[0] = info;
+    to[0] = (W_)info;
     for (i = 1; i < size_to_copy; i++) { // unroll for small i
 	to[i] = from[i];
     }
     
 #if defined(PARALLEL_GC)
-    write_barrier();
+    {
+        const StgInfoTable *new_info;
+        new_info = (const StgInfoTable *)cas((StgPtr)&src->header.info, 
+                                             (W_)info, MK_FORWARDING_PTR(to));
+        if (new_info != info) {
+#if defined(PROF_SPIN)
+            evac_collision++;
 #endif
-    src->header.info = (const StgInfoTable*)MK_FORWARDING_PTR(to);
-    
+            evacuate(p); // does the failed_to_evac stuff
+            return rtsFalse;
+        } else {
+            *p = (StgClosure*)to;
+        }
+    }
+#else
+    src->header.info = (const StgInfoTable *)MK_FORWARDING_PTR(to);
+    *p = (StgClosure*)to;
+#endif
+
 #ifdef PROFILING
     // We store the size of the just evacuated object in the LDV word so that
     // the profiler can guess the position of the next object later.
@@ -638,7 +639,7 @@ loop:
 
   case CAF_BLACKHOLE:
   case BLACKHOLE:
-      copyPart(p,q,BLACKHOLE_sizeW(),sizeofW(StgHeader),stp);
+      copyPart(p,info,q,BLACKHOLE_sizeW(),sizeofW(StgHeader),stp);
       return;
 
   case THUNK_SELECTOR:
@@ -710,7 +711,7 @@ loop:
 	  StgPtr r, s;
           rtsBool mine;
 
-	  mine = copyPart(p,(StgClosure *)tso, tso_sizeW(tso), 
+	  mine = copyPart(p,info,(StgClosure *)tso, tso_sizeW(tso), 
                           sizeofW(StgTSO), stp);
           if (mine) {
               new_tso = (StgTSO *)*p;