jdk8-mips64-public/hotspot: src/share/vm/gc_implementation/g1/g1HotCardCache.hpp@fd81a5764900 (annotated)

src/share/vm/gc_implementation/g1/g1HotCardCache.hpp@fd81a5764900 (annotated)

src/share/vm/gc_implementation/g1/g1HotCardCache.hpp

Mon, 23 Jun 2014 16:43:41 +0200

author: pliden
date: Mon, 23 Jun 2014 16:43:41 +0200
changeset 6905: fd81a5764900
parent 6552: 8847586c9037
child 6876: 710a3c8b516e
child 7051: 1f1d373cd044
permissions: -rw-r--r--

8046231: G1: Code root location ... from nmethod ... not in strong code roots for region
Reviewed-by: tschatzl, ehelin

 /*
  * Copyright (c) 2013, 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.
  *
  */
 #ifndef SHARE_VM_GC_IMPLEMENTATION_G1_G1HOTCARDCACHE_HPP
 #define SHARE_VM_GC_IMPLEMENTATION_G1_G1HOTCARDCACHE_HPP
 #include "gc_implementation/g1/g1_globals.hpp"
 #include "gc_implementation/g1/g1CardCounts.hpp"
 #include "memory/allocation.hpp"
 #include "runtime/safepoint.hpp"
 #include "runtime/thread.inline.hpp"
 #include "utilities/globalDefinitions.hpp"
 class DirtyCardQueue;
 class G1CollectedHeap;
 class G1RemSet;
 class HeapRegion;
 // An evicting cache of cards that have been logged by the G1 post
 // write barrier. Placing a card in the cache delays the refinement
 // of the card until the card is evicted, or the cache is drained
 // during the next evacuation pause.
 //
 // The first thing the G1 post write barrier does is to check whether
 // the card containing the updated pointer is already dirty and, if
 // so, skips the remaining code in the barrier.
 //
 // Delaying the refinement of a card will make the card fail the
 // first is_dirty check in the write barrier, skipping the remainder
 // of the write barrier.
 //
 // This can significantly reduce the overhead of the write barrier
 // code, increasing throughput.
 class G1HotCardCache: public CHeapObj<mtGC> {
   G1CollectedHeap*   _g1h;
   // The card cache table
   jbyte**      _hot_cache;
   int          _hot_cache_size;
   int          _n_hot;
   int          _hot_cache_idx;
   int          _hot_cache_par_chunk_size;
   volatile int _hot_cache_par_claimed_idx;
   bool         _use_cache;
   G1CardCounts _card_counts;
   bool default_use_cache() const {
     return (G1ConcRSLogCacheSize > 0);
   }
  public:
   G1HotCardCache(G1CollectedHeap* g1h);
   ~G1HotCardCache();
   void initialize();
   bool use_cache() { return _use_cache; }
   void set_use_cache(bool b) {
     _use_cache = (b ? default_use_cache() : false);
   }
   // Returns the card to be refined or NULL.
   //
   // Increments the count for given the card. if the card is not 'hot',
   // it is returned for immediate refining. Otherwise the card is
   // added to the hot card cache.
   // If there is enough room in the hot card cache for the card we're
   // adding, NULL is returned and no further action in needed.
   // If we evict a card from the cache to make room for the new card,
   // the evicted card is then returned for refinement.
   jbyte* insert(jbyte* card_ptr);
   // Refine the cards that have delayed as a result of
   // being in the cache.
   void drain(uint worker_i, G1RemSet* g1rs, DirtyCardQueue* into_cset_dcq);
   // Set up for parallel processing of the cards in the hot cache
   void reset_hot_cache_claimed_index() {
     _hot_cache_par_claimed_idx = 0;
   }
   // Resets the hot card cache and discards the entries.
   void reset_hot_cache() {
     assert(SafepointSynchronize::is_at_safepoint(), "Should be at a safepoint");
     assert(Thread::current()->is_VM_thread(), "Current thread should be the VMthread");
     _hot_cache_idx = 0; _n_hot = 0;
   }
   bool hot_cache_is_empty() { return _n_hot == 0; }
   // Resizes the card counts table to match the given capacity
   void resize_card_counts(size_t heap_capacity);
   // Zeros the values in the card counts table for entire committed heap
   void reset_card_counts();
   // Zeros the values in the card counts table for the given region
   void reset_card_counts(HeapRegion* hr);
 };
 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1HOTCARDCACHE_HPP

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/gc_implementation/g1/g1HotCardCache.hpp@fd81a5764900 (annotated)

src/share/vm/gc_implementation/g1/g1HotCardCache.hpp