jdk8-mips64-public/hotspot: src/share/vm/gc_implementation/g1/g1RemSet.hpp@5f429ee79634 (annotated)

src/share/vm/gc_implementation/g1/g1RemSet.hpp@5f429ee79634 (annotated)

src/share/vm/gc_implementation/g1/g1RemSet.hpp

Mon, 09 Aug 2010 05:41:05 -0700

author: jcoomes
date: Mon, 09 Aug 2010 05:41:05 -0700
changeset 2064: 5f429ee79634
parent 2063: a03ae377b2e8
child 2216: c32059ef4dc0
permissions: -rw-r--r--

6966222: G1: simplify TaskQueue overflow handling
Reviewed-by: tonyp, ysr

 /*
  * Copyright (c) 2001, 2010, 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.
  *
  */
 // A G1RemSet provides ways of iterating over pointers into a selected
 // collection set.
 class G1CollectedHeap;
 class CardTableModRefBarrierSet;
 class HRInto_G1RemSet;
 class ConcurrentG1Refine;
 class G1RemSet: public CHeapObj {
 protected:
   G1CollectedHeap* _g1;
   unsigned _conc_refine_cards;
   size_t n_workers();
 public:
   G1RemSet(G1CollectedHeap* g1) :
     _g1(g1), _conc_refine_cards(0)
   {}
   // Invoke "blk->do_oop" on all pointers into the CS in object in regions
   // outside the CS (having invoked "blk->set_region" to set the "from"
   // region correctly beforehand.) The "worker_i" param is for the
   // parallel case where the number of the worker thread calling this
   // function can be helpful in partitioning the work to be done. It
   // should be the same as the "i" passed to the calling thread's
   // work(i) function. In the sequential case this param will be ingored.
   virtual void oops_into_collection_set_do(OopsInHeapRegionClosure* blk,
                                            int worker_i) = 0;
   // Prepare for and cleanup after an oops_into_collection_set_do
   // call.  Must call each of these once before and after (in sequential
   // code) any threads call oops into collection set do.  (This offers an
   // opportunity to sequential setup and teardown of structures needed by a
   // parallel iteration over the CS's RS.)
   virtual void prepare_for_oops_into_collection_set_do() = 0;
   virtual void cleanup_after_oops_into_collection_set_do() = 0;
   // If "this" is of the given subtype, return "this", else "NULL".
   virtual HRInto_G1RemSet* as_HRInto_G1RemSet() { return NULL; }
   // Record, if necessary, the fact that *p (where "p" is in region "from",
   // and is, a fortiori, required to be non-NULL) has changed to its new value.
   virtual void write_ref(HeapRegion* from, oop* p) = 0;
   virtual void write_ref(HeapRegion* from, narrowOop* p) = 0;
   virtual void par_write_ref(HeapRegion* from, oop* p, int tid) = 0;
   virtual void par_write_ref(HeapRegion* from, narrowOop* p, int tid) = 0;
   // Requires "region_bm" and "card_bm" to be bitmaps with 1 bit per region
   // or card, respectively, such that a region or card with a corresponding
   // 0 bit contains no part of any live object.  Eliminates any remembered
   // set entries that correspond to dead heap ranges.
   virtual void scrub(BitMap* region_bm, BitMap* card_bm) = 0;
   // Like the above, but assumes is called in parallel: "worker_num" is the
   // parallel thread id of the current thread, and "claim_val" is the
   // value that should be used to claim heap regions.
   virtual void scrub_par(BitMap* region_bm, BitMap* card_bm,
                          int worker_num, int claim_val) = 0;
   // Refine the card corresponding to "card_ptr".  If "sts" is non-NULL,
   // join and leave around parts that must be atomic wrt GC.  (NULL means
   // being done at a safepoint.)
   // With some implementations of this routine, when check_for_refs_into_cset
   // is true, a true result may be returned if the given card contains oops
   // that have references into the current collection set.
   virtual bool concurrentRefineOneCard(jbyte* card_ptr, int worker_i,
                                        bool check_for_refs_into_cset) {
     return false;
   }
   // Print any relevant summary info.
   virtual void print_summary_info() {}
   // Prepare remebered set for verification.
   virtual void prepare_for_verify() {};
 };
 // The simplest possible G1RemSet: iterates over all objects in non-CS
 // regions, searching for pointers into the CS.
 class StupidG1RemSet: public G1RemSet {
 public:
   StupidG1RemSet(G1CollectedHeap* g1) : G1RemSet(g1) {}
   void oops_into_collection_set_do(OopsInHeapRegionClosure* blk,
                                    int worker_i);
   void prepare_for_oops_into_collection_set_do() {}
   void cleanup_after_oops_into_collection_set_do() {}
   // Nothing is necessary in the version below.
   void write_ref(HeapRegion* from, oop* p) {}
   void write_ref(HeapRegion* from, narrowOop* p) {}
   void par_write_ref(HeapRegion* from, oop* p, int tid) {}
   void par_write_ref(HeapRegion* from, narrowOop* p, int tid) {}
   void scrub(BitMap* region_bm, BitMap* card_bm) {}
   void scrub_par(BitMap* region_bm, BitMap* card_bm,
                  int worker_num, int claim_val) {}
 };
 // A G1RemSet in which each heap region has a rem set that records the
 // external heap references into it.  Uses a mod ref bs to track updates,
 // so that they can be used to update the individual region remsets.
 class HRInto_G1RemSet: public G1RemSet {
 protected:
   enum SomePrivateConstants {
     UpdateRStoMergeSync  = 0,
     MergeRStoDoDirtySync = 1,
     DoDirtySync          = 2,
     LastSync             = 3,
     SeqTask              = 0,
     NumSeqTasks          = 1
   };
   CardTableModRefBS*             _ct_bs;
   SubTasksDone*                  _seq_task;
   G1CollectorPolicy* _g1p;
   ConcurrentG1Refine* _cg1r;
   size_t*             _cards_scanned;
   size_t              _total_cards_scanned;
   // _traversal_in_progress is "true" iff a traversal is in progress.
   bool _traversal_in_progress;
   void set_traversal(bool b) { _traversal_in_progress = b; }
   // Used for caching the closure that is responsible for scanning
   // references into the collection set.
   OopsInHeapRegionClosure** _cset_rs_update_cl;
   // The routine that performs the actual work of refining a dirty
   // card.
   // If check_for_refs_into_refs is true then a true result is returned
   // if the card contains oops that have references into the current
   // collection set.
   bool concurrentRefineOneCard_impl(jbyte* card_ptr, int worker_i,
                                     bool check_for_refs_into_cset);
 protected:
   template <class T> void write_ref_nv(HeapRegion* from, T* p);
   template <class T> void par_write_ref_nv(HeapRegion* from, T* p, int tid);
 public:
   // This is called to reset dual hash tables after the gc pause
   // is finished and the initial hash table is no longer being
   // scanned.
   void cleanupHRRS();
   HRInto_G1RemSet(G1CollectedHeap* g1, CardTableModRefBS* ct_bs);
   ~HRInto_G1RemSet();
   void oops_into_collection_set_do(OopsInHeapRegionClosure* blk,
                                    int worker_i);
   void prepare_for_oops_into_collection_set_do();
   void cleanup_after_oops_into_collection_set_do();
   void scanRS(OopsInHeapRegionClosure* oc, int worker_i);
   template <class T> void scanNewRefsRS_work(OopsInHeapRegionClosure* oc, int worker_i);
   void scanNewRefsRS(OopsInHeapRegionClosure* oc, int worker_i) {
     if (UseCompressedOops) {
       scanNewRefsRS_work<narrowOop>(oc, worker_i);
     } else {
       scanNewRefsRS_work<oop>(oc, worker_i);
     }
   }
   void updateRS(DirtyCardQueue* into_cset_dcq, int worker_i);
   HeapRegion* calculateStartRegion(int i);
   HRInto_G1RemSet* as_HRInto_G1RemSet() { return this; }
   CardTableModRefBS* ct_bs() { return _ct_bs; }
   size_t cardsScanned() { return _total_cards_scanned; }
   // Record, if necessary, the fact that *p (where "p" is in region "from",
   // which is required to be non-NULL) has changed to a new non-NULL value.
   // [Below the virtual version calls a non-virtual protected
   // workhorse that is templatified for narrow vs wide oop.]
   inline void write_ref(HeapRegion* from, oop* p) {
     write_ref_nv(from, p);
   }
   inline void write_ref(HeapRegion* from, narrowOop* p) {
     write_ref_nv(from, p);
   }
   inline void par_write_ref(HeapRegion* from, oop* p, int tid) {
     par_write_ref_nv(from, p, tid);
   }
   inline void par_write_ref(HeapRegion* from, narrowOop* p, int tid) {
     par_write_ref_nv(from, p, tid);
   }
   bool self_forwarded(oop obj);
   void scrub(BitMap* region_bm, BitMap* card_bm);
   void scrub_par(BitMap* region_bm, BitMap* card_bm,
                  int worker_num, int claim_val);
   // If check_for_refs_into_cset is true then a true result is returned
   // if the card contains oops that have references into the current
   // collection set.
   virtual bool concurrentRefineOneCard(jbyte* card_ptr, int worker_i,
                                        bool check_for_refs_into_cset);
   virtual void print_summary_info();
   virtual void prepare_for_verify();
 };
 #define G1_REM_SET_LOGGING 0
 class CountNonCleanMemRegionClosure: public MemRegionClosure {
   G1CollectedHeap* _g1;
   int _n;
   HeapWord* _start_first;
 public:
   CountNonCleanMemRegionClosure(G1CollectedHeap* g1) :
     _g1(g1), _n(0), _start_first(NULL)
   {}
   void do_MemRegion(MemRegion mr);
   int n() { return _n; };
   HeapWord* start_first() { return _start_first; }
 };
 class UpdateRSOopClosure: public OopClosure {
   HeapRegion* _from;
   HRInto_G1RemSet* _rs;
   int _worker_i;
   template <class T> void do_oop_work(T* p);
 public:
   UpdateRSOopClosure(HRInto_G1RemSet* rs, int worker_i = 0) :
     _from(NULL), _rs(rs), _worker_i(worker_i) {
     guarantee(_rs != NULL, "Requires an HRIntoG1RemSet");
   }
   void set_from(HeapRegion* from) {
     assert(from != NULL, "from region must be non-NULL");
     _from = from;
   }
   virtual void do_oop(narrowOop* p) { do_oop_work(p); }
   virtual void do_oop(oop* p)       { do_oop_work(p); }
   // Override: this closure is idempotent.
   //  bool idempotent() { return true; }
   bool apply_to_weak_ref_discovered_field() { return true; }
 };
 class UpdateRSetImmediate: public OopsInHeapRegionClosure {
 private:
   G1RemSet* _g1_rem_set;
   template <class T> void do_oop_work(T* p);
 public:
   UpdateRSetImmediate(G1RemSet* rs) :
     _g1_rem_set(rs) {}
   virtual void do_oop(narrowOop* p) { do_oop_work(p); }
   virtual void do_oop(      oop* p) { do_oop_work(p); }
 };

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/gc_implementation/g1/g1RemSet.hpp@5f429ee79634 (annotated)

src/share/vm/gc_implementation/g1/g1RemSet.hpp