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

Instead of keeping a single list of all threads, keep one per step
and only look at the threads belonging to steps that we are
collecting.

1 files changed, 3 insertions, 0 deletions

diff --git a/includes/Storage.h b/includes/Storage.h
index 90e364cbc4..c9cbd9c5e9 100644
--- a/includes/Storage.h
+++ b/includes/Storage.h
@@ -69,6 +69,8 @@ typedef struct step_ {
     bdescr *             large_objects;	 // large objects (doubly linked)
     unsigned int         n_large_blocks; // no. of blocks used by large objs
 
+    StgTSO *             threads;       // threads in this step
+                                        // linked via global_link
 
     // ------------------------------------
     // Fields below are used during GC only
@@ -100,6 +102,7 @@ typedef struct step_ {
 
     bdescr *     bitmap;  		// bitmap for compacting collection
 
+    StgTSO *     old_threads;
 
 } step;