small debug output improvements

[ghc-hetmet.git] / rts / sm / GCUtils.c

diff --git a/rts/sm/GCUtils.c b/rts/sm/GCUtils.c
index 636f23d..98e6f8a 100644 (file)
--- a/rts/sm/GCUtils.c
+++ b/rts/sm/GCUtils.c
@@ -65,6 +65,9 @@ grab_todo_block (step_workspace *ws)
     ACQUIRE_SPIN_LOCK(&stp->sync_todo);
     if (stp->todos) {
        bd = stp->todos;
+        if (stp->todos == stp->todos_last) {
+            stp->todos_last = NULL;
+        }
        stp->todos = bd->link;
         stp->n_todos--;
        bd->link = NULL;
@@ -78,10 +81,15 @@ push_todo_block (bdescr *bd, step *stp)
 {
     ASSERT(bd->link == NULL);
     ACQUIRE_SPIN_LOCK(&stp->sync_todo);
-    bd->link = stp->todos;
-    stp->todos = bd;
+    if (stp->todos_last == NULL) {
+        stp->todos_last = bd;
+        stp->todos = bd;
+    } else {
+        stp->todos_last->link = bd;
+        stp->todos_last = bd;
+    }
     stp->n_todos++;
-    trace(TRACE_gc, "step %d, n_todos: %d", stp->abs_no, stp->n_todos);
+    trace(TRACE_gc|DEBUG_gc, "step %d, n_todos: %d", stp->abs_no, stp->n_todos);
     RELEASE_SPIN_LOCK(&stp->sync_todo);
 }