FIX (partially) #2703: bug in stack overflow handling when inside block

[ghc-hetmet.git] / rts / Schedule.c

diff --git a/rts/Schedule.c b/rts/Schedule.c
index 8c254cc..626c097 100644 (file)
--- a/rts/Schedule.c
+++ b/rts/Schedule.c
@@ -150,7 +150,7 @@ static rtsBool scheduleGetRemoteWork(Capability *cap);
 static void scheduleSendPendingMessages(void);
 static void scheduleActivateSpark(Capability *cap);
 #endif
-static void schedulePostRunThread(StgTSO *t);
+static void schedulePostRunThread(Capability *cap, StgTSO *t);
 static rtsBool scheduleHandleHeapOverflow( Capability *cap, StgTSO *t );
 static void scheduleHandleStackOverflow( Capability *cap, Task *task, 
                                         StgTSO *t);
@@ -622,7 +622,7 @@ run_thread:
     CCCS = CCS_SYSTEM;
 #endif
     
-    schedulePostRunThread(t);
+    schedulePostRunThread(cap,t);
 
     t = threadStackUnderflow(task,t);
 
@@ -1064,7 +1064,7 @@ scheduleGetRemoteWork(Capability *cap)
  * ------------------------------------------------------------------------- */
 
 static void
-schedulePostRunThread (StgTSO *t)
+schedulePostRunThread (Capability *cap, StgTSO *t)
 {
     // We have to be able to catch transactions that are in an
     // infinite loop as a result of seeing an inconsistent view of
@@ -1085,8 +1085,7 @@ schedulePostRunThread (StgTSO *t)
             // ATOMICALLY_FRAME, aborting the (nested)
             // transaction, and saving the stack of any
             // partially-evaluated thunks on the heap.
-            throwToSingleThreaded_(&capabilities[0], t, 
-                                   NULL, rtsTrue, NULL);
+            throwToSingleThreaded_(cap, t, NULL, rtsTrue, NULL);
             
             ASSERT(get_itbl((StgClosure *)t->sp)->type == ATOMICALLY_FRAME);
         }
@@ -2126,10 +2125,17 @@ threadStackOverflow(Capability *cap, StgTSO *tso)
   }
 
   /* Try to double the current stack size.  If that takes us over the
-   * maximum stack size for this thread, then use the maximum instead.
-   * Finally round up so the TSO ends up as a whole number of blocks.
+   * maximum stack size for this thread, then use the maximum instead
+   * (that is, unless we're already at or over the max size and we
+   * can't raise the StackOverflow exception (see above), in which
+   * case just double the size). Finally round up so the TSO ends up as
+   * a whole number of blocks.
    */
-  new_stack_size = stg_min(tso->stack_size * 2, tso->max_stack_size);
+  if (tso->stack_size >= tso->max_stack_size) {
+      new_stack_size = tso->stack_size * 2;
+  } else { 
+      new_stack_size = stg_min(tso->stack_size * 2, tso->max_stack_size);
+  }
   new_tso_size   = (lnat)BLOCK_ROUND_UP(new_stack_size * sizeof(W_) + 
                                       TSO_STRUCT_SIZE)/sizeof(W_);
   new_tso_size = round_to_mblocks(new_tso_size);  /* Be MBLOCK-friendly */