aoqi@0: /*
aoqi@0:  * Copyright (c) 2001, 2013, Oracle and/or its affiliates. All rights reserved.
aoqi@0:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
aoqi@0:  *
aoqi@0:  * This code is free software; you can redistribute it and/or modify it
aoqi@0:  * under the terms of the GNU General Public License version 2 only, as
aoqi@0:  * published by the Free Software Foundation.
aoqi@0:  *
aoqi@0:  * This code is distributed in the hope that it will be useful, but WITHOUT
aoqi@0:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
aoqi@0:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
aoqi@0:  * version 2 for more details (a copy is included in the LICENSE file that
aoqi@0:  * accompanied this code).
aoqi@0:  *
aoqi@0:  * You should have received a copy of the GNU General Public License version
aoqi@0:  * 2 along with this work; if not, write to the Free Software Foundation,
aoqi@0:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
aoqi@0:  *
aoqi@0:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
aoqi@0:  * or visit www.oracle.com if you need additional information or have any
aoqi@0:  * questions.
aoqi@0:  *
aoqi@0:  */
aoqi@0: 
aoqi@0: #ifndef SHARE_VM_MEMORY_CARDTABLERS_HPP
aoqi@0: #define SHARE_VM_MEMORY_CARDTABLERS_HPP
aoqi@0: 
aoqi@0: #include "memory/cardTableModRefBS.hpp"
aoqi@0: #include "memory/genRemSet.hpp"
aoqi@0: #include "memory/memRegion.hpp"
aoqi@0: 
aoqi@0: class Space;
aoqi@0: class OopsInGenClosure;
aoqi@0: 
aoqi@0: // This kind of "GenRemSet" uses a card table both as shared data structure
aoqi@0: // for a mod ref barrier set and for the rem set information.
aoqi@0: 
aoqi@0: class CardTableRS: public GenRemSet {
aoqi@0:   friend class VMStructs;
aoqi@0:   // Below are private classes used in impl.
aoqi@0:   friend class VerifyCTSpaceClosure;
aoqi@0:   friend class ClearNoncleanCardWrapper;
aoqi@0: 
aoqi@0:   static jbyte clean_card_val() {
aoqi@0:     return CardTableModRefBS::clean_card;
aoqi@0:   }
aoqi@0: 
aoqi@0:   static intptr_t clean_card_row() {
aoqi@0:     return CardTableModRefBS::clean_card_row;
aoqi@0:   }
aoqi@0: 
aoqi@0:   static bool
aoqi@0:   card_is_dirty_wrt_gen_iter(jbyte cv) {
aoqi@0:     return CardTableModRefBS::card_is_dirty_wrt_gen_iter(cv);
aoqi@0:   }
aoqi@0: 
aoqi@0:   CardTableModRefBSForCTRS* _ct_bs;
aoqi@0: 
aoqi@0:   virtual void younger_refs_in_space_iterate(Space* sp, OopsInGenClosure* cl);
aoqi@0: 
aoqi@0:   void verify_space(Space* s, HeapWord* gen_start);
aoqi@0: 
aoqi@0:   enum ExtendedCardValue {
aoqi@0:     youngergen_card   = CardTableModRefBS::CT_MR_BS_last_reserved + 1,
aoqi@0:     // These are for parallel collection.
aoqi@0:     // There are three P (parallel) youngergen card values.  In general, this
aoqi@0:     // needs to be more than the number of generations (including the perm
aoqi@0:     // gen) that might have younger_refs_do invoked on them separately.  So
aoqi@0:     // if we add more gens, we have to add more values.
aoqi@0:     youngergenP1_card  = CardTableModRefBS::CT_MR_BS_last_reserved + 2,
aoqi@0:     youngergenP2_card  = CardTableModRefBS::CT_MR_BS_last_reserved + 3,
aoqi@0:     youngergenP3_card  = CardTableModRefBS::CT_MR_BS_last_reserved + 4,
aoqi@0:     cur_youngergen_and_prev_nonclean_card =
aoqi@0:       CardTableModRefBS::CT_MR_BS_last_reserved + 5
aoqi@0:   };
aoqi@0: 
aoqi@0:   // An array that contains, for each generation, the card table value last
aoqi@0:   // used as the current value for a younger_refs_do iteration of that
aoqi@0:   // portion of the table.  (The perm gen is index 0; other gens are at
aoqi@0:   // their level plus 1.  They youngest gen is in the table, but will
aoqi@0:   // always have the value "clean_card".)
aoqi@0:   jbyte* _last_cur_val_in_gen;
aoqi@0: 
aoqi@0:   jbyte _cur_youngergen_card_val;
aoqi@0: 
aoqi@0:   int _regions_to_iterate;
aoqi@0: 
aoqi@0:   jbyte cur_youngergen_card_val() {
aoqi@0:     return _cur_youngergen_card_val;
aoqi@0:   }
aoqi@0:   void set_cur_youngergen_card_val(jbyte v) {
aoqi@0:     _cur_youngergen_card_val = v;
aoqi@0:   }
aoqi@0:   bool is_prev_youngergen_card_val(jbyte v) {
aoqi@0:     return
aoqi@0:       youngergen_card <= v &&
aoqi@0:       v < cur_youngergen_and_prev_nonclean_card &&
aoqi@0:       v != _cur_youngergen_card_val;
aoqi@0:   }
aoqi@0:   // Return a youngergen_card_value that is not currently in use.
aoqi@0:   jbyte find_unused_youngergenP_card_value();
aoqi@0: 
aoqi@0: public:
aoqi@0:   CardTableRS(MemRegion whole_heap, int max_covered_regions);
aoqi@0:   ~CardTableRS();
aoqi@0: 
aoqi@0:   // *** GenRemSet functions.
aoqi@0:   GenRemSet::Name rs_kind() { return GenRemSet::CardTable; }
aoqi@0: 
aoqi@0:   CardTableRS* as_CardTableRS() { return this; }
aoqi@0: 
aoqi@0:   CardTableModRefBS* ct_bs() { return _ct_bs; }
aoqi@0: 
aoqi@0:   // Override.
aoqi@0:   void prepare_for_younger_refs_iterate(bool parallel);
aoqi@0: 
aoqi@0:   // Card table entries are cleared before application; "blk" is
aoqi@0:   // responsible for dirtying if the oop is still older-to-younger after
aoqi@0:   // closure application.
aoqi@0:   void younger_refs_iterate(Generation* g, OopsInGenClosure* blk);
aoqi@0: 
aoqi@0:   void inline_write_ref_field_gc(void* field, oop new_val) {
aoqi@0:     jbyte* byte = _ct_bs->byte_for(field);
fujie@116: #ifdef MIPS64
fujie@121:     if (Use3A2000) OrderAccess::fence();
fujie@116: #endif
fujie@116:    *byte = youngergen_card;
fujie@116: #ifdef MIPS64
fujie@121:    if (Use3A2000) OrderAccess::fence();
fujie@116: #endif
fujie@116: 
aoqi@0:   }
aoqi@0:   void write_ref_field_gc_work(void* field, oop new_val) {
aoqi@0:     inline_write_ref_field_gc(field, new_val);
aoqi@0:   }
aoqi@0: 
aoqi@0:   // Override.  Might want to devirtualize this in the same fashion as
aoqi@0:   // above.  Ensures that the value of the card for field says that it's
aoqi@0:   // a younger card in the current collection.
aoqi@0:   virtual void write_ref_field_gc_par(void* field, oop new_val);
aoqi@0: 
aoqi@0:   void resize_covered_region(MemRegion new_region);
aoqi@0: 
aoqi@0:   bool is_aligned(HeapWord* addr) {
aoqi@0:     return _ct_bs->is_card_aligned(addr);
aoqi@0:   }
aoqi@0: 
aoqi@0:   void verify();
aoqi@0:   void verify_aligned_region_empty(MemRegion mr);
aoqi@0: 
aoqi@0:   void clear(MemRegion mr) { _ct_bs->clear(mr); }
aoqi@0:   void clear_into_younger(Generation* old_gen);
aoqi@0: 
aoqi@0:   void invalidate(MemRegion mr, bool whole_heap = false) {
aoqi@0:     _ct_bs->invalidate(mr, whole_heap);
aoqi@0:   }
aoqi@0:   void invalidate_or_clear(Generation* old_gen);
aoqi@0: 
aoqi@0:   static uintx ct_max_alignment_constraint() {
aoqi@0:     return CardTableModRefBS::ct_max_alignment_constraint();
aoqi@0:   }
aoqi@0: 
aoqi@0:   jbyte* byte_for(void* p)     { return _ct_bs->byte_for(p); }
aoqi@0:   jbyte* byte_after(void* p)   { return _ct_bs->byte_after(p); }
aoqi@0:   HeapWord* addr_for(jbyte* p) { return _ct_bs->addr_for(p); }
aoqi@0: 
aoqi@0:   bool is_prev_nonclean_card_val(jbyte v) {
aoqi@0:     return
aoqi@0:       youngergen_card <= v &&
aoqi@0:       v <= cur_youngergen_and_prev_nonclean_card &&
aoqi@0:       v != _cur_youngergen_card_val;
aoqi@0:   }
aoqi@0: 
aoqi@0:   static bool youngergen_may_have_been_dirty(jbyte cv) {
aoqi@0:     return cv == CardTableRS::cur_youngergen_and_prev_nonclean_card;
aoqi@0:   }
aoqi@0: 
aoqi@0: };
aoqi@0: 
aoqi@0: class ClearNoncleanCardWrapper: public MemRegionClosure {
aoqi@0:   DirtyCardToOopClosure* _dirty_card_closure;
aoqi@0:   CardTableRS* _ct;
aoqi@0:   bool _is_par;
aoqi@0: private:
aoqi@0:   // Clears the given card, return true if the corresponding card should be
aoqi@0:   // processed.
aoqi@0:   inline bool clear_card(jbyte* entry);
aoqi@0:   // Work methods called by the clear_card()
aoqi@0:   inline bool clear_card_serial(jbyte* entry);
aoqi@0:   inline bool clear_card_parallel(jbyte* entry);
aoqi@0:   // check alignment of pointer
aoqi@0:   bool is_word_aligned(jbyte* entry);
aoqi@0: 
aoqi@0: public:
aoqi@0:   ClearNoncleanCardWrapper(DirtyCardToOopClosure* dirty_card_closure, CardTableRS* ct);
aoqi@0:   void do_MemRegion(MemRegion mr);
aoqi@0: };
aoqi@0: 
aoqi@0: #endif // SHARE_VM_MEMORY_CARDTABLERS_HPP