diff src/share/vm/gc_implementation/g1/g1MarkSweep.cpp @ 2152:0fa27f37d4d4

6977804: G1: remove the zero-filling thread Summary: This changeset removes the zero-filling thread from G1 and collapses the two free region lists we had before (the "free" and "unclean" lists) into one. The new free list uses the new heap region sets / lists abstractions that we'll ultimately use it to keep track of all regions in the heap. A heap region set was also introduced for the humongous regions. Finally, this change increases the concurrency between the thread that completes freeing regions (after a cleanup pause) and the rest of the system (before we'd have to wait for said thread to complete before allocating a new region). The changest also includes a lot of refactoring and code simplification. Reviewed-by: jcoomes, johnc
author tonyp
date Wed, 19 Jan 2011 19:30:42 -0500
parents f95d63e2154a
children 377371490991
line wrap: on
line diff
--- a/src/share/vm/gc_implementation/g1/g1MarkSweep.cpp	Wed Jan 19 13:04:37 2011 -0800
+++ b/src/share/vm/gc_implementation/g1/g1MarkSweep.cpp	Wed Jan 19 19:30:42 2011 -0500
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2001, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2001, 2011, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -180,26 +180,46 @@
 }
 
 class G1PrepareCompactClosure: public HeapRegionClosure {
+  G1CollectedHeap* _g1h;
   ModRefBarrierSet* _mrbs;
   CompactPoint _cp;
+  size_t _pre_used;
+  FreeRegionList _free_list;
+  HumongousRegionSet _humongous_proxy_set;
 
   void free_humongous_region(HeapRegion* hr) {
-    HeapWord* bot = hr->bottom();
     HeapWord* end = hr->end();
     assert(hr->startsHumongous(),
            "Only the start of a humongous region should be freed.");
-    G1CollectedHeap::heap()->free_region(hr);
+    _g1h->free_humongous_region(hr, &_pre_used, &_free_list,
+                                &_humongous_proxy_set, false /* par */);
+    // Do we also need to do this for the continues humongous regions
+    // we just collapsed?
     hr->prepare_for_compaction(&_cp);
     // Also clear the part of the card table that will be unused after
     // compaction.
-    _mrbs->clear(MemRegion(hr->compaction_top(), hr->end()));
+    _mrbs->clear(MemRegion(hr->compaction_top(), end));
   }
 
 public:
-  G1PrepareCompactClosure(CompactibleSpace* cs) :
+  G1PrepareCompactClosure(CompactibleSpace* cs)
+  : _g1h(G1CollectedHeap::heap()),
+    _mrbs(G1CollectedHeap::heap()->mr_bs()),
     _cp(NULL, cs, cs->initialize_threshold()),
-    _mrbs(G1CollectedHeap::heap()->mr_bs())
-  {}
+    _pre_used(0),
+    _free_list("Local Free List for G1MarkSweep"),
+    _humongous_proxy_set("G1MarkSweep Humongous Proxy Set") { }
+
+  void update_sets() {
+    // We'll recalculate total used bytes and recreate the free list
+    // at the end of the GC, so no point in updating those values here.
+    _g1h->update_sets_after_freeing_regions(0, /* pre_used */
+                                            NULL, /* free_list */
+                                            &_humongous_proxy_set,
+                                            false /* par */);
+    _free_list.remove_all();
+  }
+
   bool doHeapRegion(HeapRegion* hr) {
     if (hr->isHumongous()) {
       if (hr->startsHumongous()) {
@@ -265,6 +285,7 @@
 
   G1PrepareCompactClosure blk(sp);
   g1h->heap_region_iterate(&blk);
+  blk.update_sets();
 
   CompactPoint perm_cp(pg, NULL, NULL);
   pg->prepare_for_compaction(&perm_cp);