src/hotspot/share/gc/g1/g1FullGCCompactTask.cpp
changeset 47885 5caa1d5f74c1
child 48889 216c2aabbf1f
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/gc/g1/g1FullGCCompactTask.cpp	Tue Nov 14 11:33:23 2017 +0100
@@ -0,0 +1,111 @@
+/*
+ * Copyright (c) 2017, 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
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#include "precompiled.hpp"
+#include "gc/g1/g1CollectedHeap.hpp"
+#include "gc/g1/g1ConcurrentMarkBitMap.inline.hpp"
+#include "gc/g1/g1FullCollector.hpp"
+#include "gc/g1/g1FullGCCompactionPoint.hpp"
+#include "gc/g1/g1FullGCCompactTask.hpp"
+#include "gc/g1/heapRegion.inline.hpp"
+#include "gc/shared/gcTraceTime.inline.hpp"
+#include "logging/log.hpp"
+#include "utilities/ticks.inline.hpp"
+
+class G1ResetHumongousClosure : public HeapRegionClosure {
+  G1CMBitMap* _bitmap;
+
+public:
+  G1ResetHumongousClosure(G1CMBitMap* bitmap) :
+      _bitmap(bitmap) { }
+
+  bool doHeapRegion(HeapRegion* current) {
+    if (current->is_humongous()) {
+      if (current->is_starts_humongous()) {
+        oop obj = oop(current->bottom());
+        if (_bitmap->is_marked(obj)) {
+          // Clear bitmap and fix mark word.
+          _bitmap->clear(obj);
+          obj->init_mark();
+        } else {
+          assert(current->is_empty(), "Should have been cleared in phase 2.");
+        }
+      }
+      current->reset_during_compaction();
+    }
+    return false;
+  }
+};
+
+size_t G1FullGCCompactTask::G1CompactRegionClosure::apply(oop obj) {
+  size_t size = obj->size();
+  HeapWord* destination = (HeapWord*)obj->forwardee();
+  if (destination == NULL) {
+    // Object not moving
+    return size;
+  }
+
+  // copy object and reinit its mark
+  HeapWord* obj_addr = (HeapWord*) obj;
+  assert(obj_addr != destination, "everything in this pass should be moving");
+  Copy::aligned_conjoint_words(obj_addr, destination, size);
+  oop(destination)->init_mark();
+  assert(oop(destination)->klass() != NULL, "should have a class");
+
+  return size;
+}
+
+void G1FullGCCompactTask::compact_region(HeapRegion* hr) {
+  assert(!hr->is_humongous(), "Should be no humongous regions in compaction queue");
+  G1CompactRegionClosure compact(collector()->mark_bitmap());
+  hr->apply_to_marked_objects(collector()->mark_bitmap(), &compact);
+  // Once all objects have been moved the liveness information
+  // needs be cleared.
+  collector()->mark_bitmap()->clear_region(hr);
+  hr->complete_compaction();
+}
+
+void G1FullGCCompactTask::work(uint worker_id) {
+  Ticks start = Ticks::now();
+  GrowableArray<HeapRegion*>* compaction_queue = collector()->compaction_point(worker_id)->regions();
+  for (GrowableArrayIterator<HeapRegion*> it = compaction_queue->begin();
+       it != compaction_queue->end();
+       ++it) {
+    compact_region(*it);
+  }
+
+  G1ResetHumongousClosure hc(collector()->mark_bitmap());
+  G1CollectedHeap::heap()->heap_region_par_iterate_from_worker_offset(&hc, &_claimer, worker_id);
+  log_task("Compaction task", worker_id, start);
+}
+
+void G1FullGCCompactTask::serial_compaction() {
+  GCTraceTime(Debug, gc, phases) tm("Phase 4: Serial Compaction", collector()->scope()->timer());
+  GrowableArray<HeapRegion*>* compaction_queue = collector()->serial_compaction_point()->regions();
+  for (GrowableArrayIterator<HeapRegion*> it = compaction_queue->begin();
+       it != compaction_queue->end();
+       ++it) {
+    compact_region(*it);
+  }
+}