Don't traverse the entire list of threads on every GC (phase 1)

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

diff --git a/rts/sm/GC.c b/rts/sm/GC.c
index f869ec4..3cb71fa 100644 (file)
--- a/rts/sm/GC.c
+++ b/rts/sm/GC.c
@@ -1078,14 +1078,19 @@ init_collected_gen (nat g, nat n_threads)
 
     for (s = 0; s < generations[g].n_steps; s++) {
 
+       stp = &generations[g].steps[s];
+       ASSERT(stp->gen_no == g);
+
+        // we'll construct a new list of threads in this step
+        // during GC, throw away the current list.
+        stp->old_threads = stp->threads;
+        stp->threads = END_TSO_QUEUE;
+
        // generation 0, step 0 doesn't need to-space 
        if (g == 0 && s == 0 && RtsFlags.GcFlags.generations > 1) { 
            continue; 
        }
        
-       stp = &generations[g].steps[s];
-       ASSERT(stp->gen_no == g);
-
        // deprecate the existing blocks
        stp->old_blocks   = stp->blocks;
        stp->n_old_blocks = stp->n_blocks;