ysr@777: /*
ysr@777:  * Copyright 2001-2007 Sun Microsystems, Inc.  All Rights Reserved.
ysr@777:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
ysr@777:  *
ysr@777:  * This code is free software; you can redistribute it and/or modify it
ysr@777:  * under the terms of the GNU General Public License version 2 only, as
ysr@777:  * published by the Free Software Foundation.
ysr@777:  *
ysr@777:  * This code is distributed in the hope that it will be useful, but WITHOUT
ysr@777:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
ysr@777:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
ysr@777:  * version 2 for more details (a copy is included in the LICENSE file that
ysr@777:  * accompanied this code).
ysr@777:  *
ysr@777:  * You should have received a copy of the GNU General Public License version
ysr@777:  * 2 along with this work; if not, write to the Free Software Foundation,
ysr@777:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
ysr@777:  *
ysr@777:  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
ysr@777:  * CA 95054 USA or visit www.sun.com if you need additional information or
ysr@777:  * have any questions.
ysr@777:  *
ysr@777:  */
ysr@777: 
ysr@777: // Forward decl
ysr@777: class ConcurrentG1RefineThread;
ysr@777: class G1RemSet;
ysr@777: 
ysr@777: // What to do after a yield:
ysr@777: enum PostYieldAction {
ysr@777:   PYA_continue,  // Continue the traversal
ysr@777:   PYA_restart,   // Restart
ysr@777:   PYA_cancel     // It's been completed by somebody else: cancel.
ysr@777: };
ysr@777: 
ysr@777: class ConcurrentG1Refine {
ysr@777:   ConcurrentG1RefineThread* _cg1rThread;
ysr@777: 
ysr@777:   volatile jint _pya;
ysr@777:   PostYieldAction _last_pya;
ysr@777: 
ysr@777:   static bool _enabled;  // Protected by G1ConcRefine_mon.
ysr@777:   unsigned _traversals;
ysr@777: 
ysr@777:   // Number of cards processed during last refinement traversal.
ysr@777:   unsigned _first_traversal;
ysr@777:   unsigned _last_cards_during;
ysr@777: 
ysr@777:   // The cache for card refinement.
ysr@777:   bool     _use_cache;
ysr@777:   bool     _def_use_cache;
ysr@777:   size_t _n_periods;
ysr@777:   size_t _total_cards;
ysr@777:   size_t _total_travs;
ysr@777: 
ysr@777:   unsigned char*  _card_counts;
ysr@777:   unsigned _n_card_counts;
ysr@777:   const jbyte* _ct_bot;
ysr@777:   unsigned* _cur_card_count_histo;
ysr@777:   unsigned* _cum_card_count_histo;
ysr@777:   jbyte**  _hot_cache;
ysr@777:   int      _hot_cache_size;
ysr@777:   int      _n_hot;
ysr@777:   int      _hot_cache_idx;
ysr@777: 
ysr@777:   // Returns the count of this card after incrementing it.
ysr@777:   int add_card_count(jbyte* card_ptr);
ysr@777: 
ysr@777:   void print_card_count_histo_range(unsigned* histo, int from, int to,
ysr@777:                                     float& cum_card_pct,
ysr@777:                                     float& cum_travs_pct);
ysr@777:  public:
ysr@777:   ConcurrentG1Refine();
ysr@777:   ~ConcurrentG1Refine();
ysr@777: 
ysr@777:   void init(); // Accomplish some initialization that has to wait.
ysr@777: 
ysr@777:   // Enabled Conc refinement, waking up thread if necessary.
ysr@777:   void enable();
ysr@777: 
ysr@777:   // Returns the number of traversals performed since this refiner was enabled.
ysr@777:   unsigned disable();
ysr@777: 
ysr@777:   // Requires G1ConcRefine_mon to be held.
ysr@777:   bool enabled() { return _enabled; }
ysr@777: 
ysr@777:   // Returns only when G1 concurrent refinement has been enabled.
ysr@777:   void wait_for_ConcurrentG1Refine_enabled();
ysr@777: 
ysr@777:   // Do one concurrent refinement pass over the card table.  Returns "true"
ysr@777:   // if heuristics determine that another pass should be done immediately.
ysr@777:   bool refine();
ysr@777: 
ysr@777:   // Indicate that an in-progress refinement pass should start over.
ysr@777:   void set_pya_restart();
ysr@777:   // Indicate that an in-progress refinement pass should quit.
ysr@777:   void set_pya_cancel();
ysr@777: 
ysr@777:   // Get the appropriate post-yield action.  Also sets last_pya.
ysr@777:   PostYieldAction get_pya();
ysr@777: 
ysr@777:   // The last PYA read by "get_pya".
ysr@777:   PostYieldAction get_last_pya();
ysr@777: 
ysr@777:   bool do_traversal();
ysr@777: 
ysr@777:   ConcurrentG1RefineThread* cg1rThread() { return _cg1rThread; }
ysr@777: 
ysr@777:   // If this is the first entry for the slot, writes into the cache and
ysr@777:   // returns NULL.  If it causes an eviction, returns the evicted pointer.
ysr@777:   // Otherwise, its a cache hit, and returns NULL.
ysr@777:   jbyte* cache_insert(jbyte* card_ptr);
ysr@777: 
ysr@777:   // Process the cached entries.
ysr@777:   void clean_up_cache(int worker_i, G1RemSet* g1rs);
ysr@777: 
ysr@777:   // Discard entries in the hot cache.
ysr@777:   void clear_hot_cache() {
ysr@777:     _hot_cache_idx = 0; _n_hot = 0;
ysr@777:   }
ysr@777: 
ysr@777:   bool hot_cache_is_empty() { return _n_hot == 0; }
ysr@777: 
ysr@777:   bool use_cache() { return _use_cache; }
ysr@777:   void set_use_cache(bool b) {
ysr@777:     if (b) _use_cache = _def_use_cache;
ysr@777:     else   _use_cache = false;
ysr@777:   }
ysr@777: 
ysr@777:   void clear_and_record_card_counts();
ysr@777:   void print_final_card_counts();
ysr@777: };