X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=rts%2FThreadPaused.c;h=4882ab2374b148c603661378a8c58c9b2c989816;hb=ce14988222b8da2abc57c68a087a61efe5ba709b;hp=c32a75b9a8e9fd5c1979e31677c0133ad9756293;hpb=804a84fbc46cd07146ed7689bb8fa3e94eeb756a;p=ghc-hetmet.git

diff --git a/rts/ThreadPaused.c b/rts/ThreadPaused.c
index c32a75b..4882ab2 100644
--- a/rts/ThreadPaused.c
+++ b/rts/ThreadPaused.c
@@ -74,7 +74,7 @@ stackSqueeze(StgTSO *tso, StgPtr bottom)
 		 * screw us up if we don't check.
 		 */
 		if (upd->updatee != updatee && !closure_IND(upd->updatee)) {
-		    UPD_IND_NOLOCK(upd->updatee, updatee);
+		    UPD_IND(upd->updatee, updatee);
 		}
 
 		// now mark this update frame as a stack gap.  The gap
@@ -195,6 +195,10 @@ threadPaused(Capability *cap, StgTSO *tso)
     maybePerformBlockedException (cap, tso);
     if (tso->what_next == ThreadKilled) { return; }
 
+    // NB. Blackholing is *not* optional, we must either do lazy
+    // blackholing, or eager blackholing consistently.  See Note
+    // [upd-black-hole] in sm/Scav.c.
+
     stack_end = &tso->stack[tso->stack_size];
     
     frame = (StgClosure *)tso->sp;
@@ -231,8 +235,10 @@ threadPaused(Capability *cap, StgTSO *tso)
 			   (long)((StgPtr)frame - tso->sp));
 
 		// If this closure is already an indirection, then
-		// suspend the computation up to this point:
-		suspendComputation(cap,tso,(StgPtr)frame);
+		// suspend the computation up to this point.
+		// NB. check raiseAsync() to see what happens when
+		// we're in a loop (#2783).
+		suspendComputation(cap,tso,(StgUpdateFrame*)frame);
 
 		// Now drop the update frame, and arrange to return
 		// the value to the frame underneath:
@@ -242,14 +248,12 @@ threadPaused(Capability *cap, StgTSO *tso)
 
 		// And continue with threadPaused; there might be
 		// yet more computation to suspend.
-		threadPaused(cap,tso);
-		return;
+                frame = (StgClosure *)tso->sp + 2;
+                prev_was_update_frame = rtsFalse;
+                continue;
 	    }
 
 	    if (bh->header.info != &stg_CAF_BLACKHOLE_info) {
-#if (!defined(LAZY_BLACKHOLING)) && defined(DEBUG)
-		debugBelch("Unexpected lazy BHing required at 0x%04lx\n",(long)bh);
-#endif
 		// zero out the slop so that the sanity checker can tell
 		// where the next closure is.
 		DEBUG_FILL_SLOP(bh);
@@ -258,7 +262,7 @@ threadPaused(Capability *cap, StgTSO *tso)
 		// We pretend that bh is now dead.
 		LDV_recordDead_FILL_SLOP_DYNAMIC((StgClosure *)bh);
 #endif
-
+                // an EAGER_BLACKHOLE gets turned into a BLACKHOLE here.
 #ifdef THREADED_RTS
                 cur_bh_info = (const StgInfoTable *)
                     cas((StgVolatilePtr)&bh->header.info,