Don't traverse filled segment list in pause

2 files changed, 23 insertions, 18 deletions

diff --git a/rts/sm/NonMoving.c b/rts/sm/NonMoving.c
index 2dd201f0f9..2bd81a3cb8 100644
--- a/rts/sm/NonMoving.c
+++ b/rts/sm/NonMoving.c
@@ -708,25 +708,8 @@ static void nonmovingPrepareMark(void)
             nonmovingSegmentInfo(seg)->next_free_snap = seg->next_free;
         }
 
-        // Update filled segments' snapshot pointers and move to sweep_list
-        uint32_t n_filled = 0;
-        struct NonmovingSegment *const filled = alloca->filled;
+        alloca->saved_filled = alloca->filled;
         alloca->filled = NULL;
-        if (filled) {
-            struct NonmovingSegment *seg = filled;
-            while (true) {
-                // Set snapshot
-                nonmovingSegmentInfo(seg)->next_free_snap = seg->next_free;
-                n_filled++;
-                if (seg->link)
-                    seg = seg->link;
-                else
-                    break;
-            }
-            // add filled segments to sweep_list
-            seg->link = nonmovingHeap.sweep_list;
-            nonmovingHeap.sweep_list = filled;
-        }
 
         // N.B. It's not necessary to update snapshot pointers of active segments;
         // they were set after they were swept and haven't seen any allocation
@@ -950,6 +933,27 @@ static void nonmovingMark_(MarkQueue *mark_queue, StgWeak **dead_weaks, StgTSO *
     debugTrace(DEBUG_nonmoving_gc, "Starting mark...");
     stat_startNonmovingGc();
 
+    // Updated filled segments' snapshot pointers and move to sweep list
+    for (int alloca_idx = 0; alloca_idx < NONMOVING_ALLOCA_CNT; ++alloca_idx) {
+        struct NonmovingSegment *filled = nonmovingHeap.allocators[alloca_idx]->saved_filled;
+        uint32_t n_filled = 0;
+        if (filled) {
+            struct NonmovingSegment *seg = filled;
+            while (true) {
+                // Set snapshot
+                nonmovingSegmentInfo(seg)->next_free_snap = seg->next_free;
+                n_filled++;
+                if (seg->link)
+                    seg = seg->link;
+                else
+                    break;
+            }
+            // add filled segments to sweep_list
+            seg->link = nonmovingHeap.sweep_list;
+            nonmovingHeap.sweep_list = filled;
+        }
+    }
+
     // Do concurrent marking; most of the heap will get marked here.
     nonmovingMarkThreadsWeaks(mark_queue);
 
diff --git a/rts/sm/NonMoving.h b/rts/sm/NonMoving.h
index 36ecd8b0af..6eabcb8493 100644
--- a/rts/sm/NonMoving.h
+++ b/rts/sm/NonMoving.h
@@ -62,6 +62,7 @@ struct NonmovingSegment {
 // A non-moving allocator for a particular block size
 struct NonmovingAllocator {
     struct NonmovingSegment *filled;
+    struct NonmovingSegment *saved_filled;
     struct NonmovingSegment *active;
     // indexed by capability number
     struct NonmovingSegment *current[];