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

Wed, 30 Sep 2009 14:50:51 -0400

author
tonyp
date
Wed, 30 Sep 2009 14:50:51 -0400
changeset 1479
6270f80a7331
parent 1325
6cb8e9df7174
child 1907
c18cbe5936b8
permissions
-rw-r--r--

6890137: G1: revamp reachable object dump
Summary: Revamp the reachable object dump debugging facility.
Reviewed-by: jmasa, apetrusenko

ysr@777 1 /*
xdono@1014 2 * Copyright 2001-2009 Sun Microsystems, Inc. All Rights Reserved.
ysr@777 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
ysr@777 4 *
ysr@777 5 * This code is free software; you can redistribute it and/or modify it
ysr@777 6 * under the terms of the GNU General Public License version 2 only, as
ysr@777 7 * published by the Free Software Foundation.
ysr@777 8 *
ysr@777 9 * This code is distributed in the hope that it will be useful, but WITHOUT
ysr@777 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
ysr@777 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
ysr@777 12 * version 2 for more details (a copy is included in the LICENSE file that
ysr@777 13 * accompanied this code).
ysr@777 14 *
ysr@777 15 * You should have received a copy of the GNU General Public License version
ysr@777 16 * 2 along with this work; if not, write to the Free Software Foundation,
ysr@777 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
ysr@777 18 *
ysr@777 19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
ysr@777 20 * CA 95054 USA or visit www.sun.com if you need additional information or
ysr@777 21 * have any questions.
ysr@777 22 *
ysr@777 23 */
ysr@777 24
ysr@777 25 // A G1RemSet provides ways of iterating over pointers into a selected
ysr@777 26 // collection set.
ysr@777 27
ysr@777 28 class G1CollectedHeap;
ysr@777 29 class CardTableModRefBarrierSet;
ysr@777 30 class HRInto_G1RemSet;
ysr@777 31 class ConcurrentG1Refine;
ysr@777 32
apetrusenko@984 33 class G1RemSet: public CHeapObj {
ysr@777 34 protected:
ysr@777 35 G1CollectedHeap* _g1;
ysr@777 36 unsigned _conc_refine_cards;
ysr@777 37 size_t n_workers();
ysr@777 38
ysr@777 39 public:
ysr@777 40 G1RemSet(G1CollectedHeap* g1) :
iveresov@1229 41 _g1(g1), _conc_refine_cards(0)
ysr@777 42 {}
ysr@777 43
ysr@777 44 // Invoke "blk->do_oop" on all pointers into the CS in object in regions
ysr@777 45 // outside the CS (having invoked "blk->set_region" to set the "from"
ysr@777 46 // region correctly beforehand.) The "worker_i" param is for the
ysr@777 47 // parallel case where the number of the worker thread calling this
ysr@777 48 // function can be helpful in partitioning the work to be done. It
ysr@777 49 // should be the same as the "i" passed to the calling thread's
ysr@777 50 // work(i) function. In the sequential case this param will be ingored.
ysr@777 51 virtual void oops_into_collection_set_do(OopsInHeapRegionClosure* blk,
ysr@777 52 int worker_i) = 0;
ysr@777 53
ysr@777 54 // Prepare for and cleanup after an oops_into_collection_set_do
ysr@777 55 // call. Must call each of these once before and after (in sequential
ysr@777 56 // code) any threads call oops into collection set do. (This offers an
ysr@777 57 // opportunity to sequential setup and teardown of structures needed by a
ysr@777 58 // parallel iteration over the CS's RS.)
ysr@777 59 virtual void prepare_for_oops_into_collection_set_do() = 0;
ysr@777 60 virtual void cleanup_after_oops_into_collection_set_do() = 0;
ysr@777 61
ysr@777 62 // If "this" is of the given subtype, return "this", else "NULL".
ysr@777 63 virtual HRInto_G1RemSet* as_HRInto_G1RemSet() { return NULL; }
ysr@777 64
ysr@1280 65 // Record, if necessary, the fact that *p (where "p" is in region "from",
ysr@1280 66 // and is, a fortiori, required to be non-NULL) has changed to its new value.
ysr@777 67 virtual void write_ref(HeapRegion* from, oop* p) = 0;
ysr@1280 68 virtual void write_ref(HeapRegion* from, narrowOop* p) = 0;
ysr@777 69 virtual void par_write_ref(HeapRegion* from, oop* p, int tid) = 0;
ysr@1280 70 virtual void par_write_ref(HeapRegion* from, narrowOop* p, int tid) = 0;
ysr@777 71
ysr@777 72 // Requires "region_bm" and "card_bm" to be bitmaps with 1 bit per region
ysr@777 73 // or card, respectively, such that a region or card with a corresponding
ysr@777 74 // 0 bit contains no part of any live object. Eliminates any remembered
ysr@777 75 // set entries that correspond to dead heap ranges.
ysr@777 76 virtual void scrub(BitMap* region_bm, BitMap* card_bm) = 0;
ysr@777 77 // Like the above, but assumes is called in parallel: "worker_num" is the
ysr@777 78 // parallel thread id of the current thread, and "claim_val" is the
ysr@777 79 // value that should be used to claim heap regions.
ysr@777 80 virtual void scrub_par(BitMap* region_bm, BitMap* card_bm,
ysr@777 81 int worker_num, int claim_val) = 0;
ysr@777 82
ysr@777 83 // Refine the card corresponding to "card_ptr". If "sts" is non-NULL,
ysr@777 84 // join and leave around parts that must be atomic wrt GC. (NULL means
ysr@777 85 // being done at a safepoint.)
ysr@777 86 virtual void concurrentRefineOneCard(jbyte* card_ptr, int worker_i) {}
ysr@777 87
ysr@777 88 // Print any relevant summary info.
ysr@777 89 virtual void print_summary_info() {}
ysr@777 90
ysr@777 91 // Prepare remebered set for verification.
ysr@777 92 virtual void prepare_for_verify() {};
ysr@777 93 };
ysr@777 94
ysr@777 95
ysr@777 96 // The simplest possible G1RemSet: iterates over all objects in non-CS
ysr@777 97 // regions, searching for pointers into the CS.
ysr@777 98 class StupidG1RemSet: public G1RemSet {
ysr@777 99 public:
ysr@777 100 StupidG1RemSet(G1CollectedHeap* g1) : G1RemSet(g1) {}
ysr@777 101
ysr@777 102 void oops_into_collection_set_do(OopsInHeapRegionClosure* blk,
ysr@777 103 int worker_i);
ysr@777 104
ysr@777 105 void prepare_for_oops_into_collection_set_do() {}
ysr@777 106 void cleanup_after_oops_into_collection_set_do() {}
ysr@777 107
ysr@777 108 // Nothing is necessary in the version below.
ysr@777 109 void write_ref(HeapRegion* from, oop* p) {}
ysr@1280 110 void write_ref(HeapRegion* from, narrowOop* p) {}
ysr@777 111 void par_write_ref(HeapRegion* from, oop* p, int tid) {}
ysr@1280 112 void par_write_ref(HeapRegion* from, narrowOop* p, int tid) {}
ysr@777 113
ysr@777 114 void scrub(BitMap* region_bm, BitMap* card_bm) {}
ysr@777 115 void scrub_par(BitMap* region_bm, BitMap* card_bm,
ysr@777 116 int worker_num, int claim_val) {}
ysr@777 117
ysr@777 118 };
ysr@777 119
ysr@777 120 // A G1RemSet in which each heap region has a rem set that records the
ysr@777 121 // external heap references into it. Uses a mod ref bs to track updates,
ysr@777 122 // so that they can be used to update the individual region remsets.
ysr@777 123
ysr@777 124 class HRInto_G1RemSet: public G1RemSet {
ysr@777 125 protected:
ysr@777 126 enum SomePrivateConstants {
ysr@777 127 UpdateRStoMergeSync = 0,
ysr@777 128 MergeRStoDoDirtySync = 1,
ysr@777 129 DoDirtySync = 2,
ysr@777 130 LastSync = 3,
ysr@777 131
ysr@777 132 SeqTask = 0,
ysr@777 133 NumSeqTasks = 1
ysr@777 134 };
ysr@777 135
ysr@777 136 CardTableModRefBS* _ct_bs;
ysr@777 137 SubTasksDone* _seq_task;
ysr@777 138 G1CollectorPolicy* _g1p;
ysr@777 139
ysr@777 140 ConcurrentG1Refine* _cg1r;
ysr@777 141
ysr@777 142 size_t* _cards_scanned;
ysr@777 143 size_t _total_cards_scanned;
ysr@777 144
ysr@777 145 // _par_traversal_in_progress is "true" iff a parallel traversal is in
ysr@777 146 // progress. If so, then cards added to remembered sets should also have
ysr@777 147 // their references into the collection summarized in "_new_refs".
ysr@777 148 bool _par_traversal_in_progress;
iveresov@1229 149 void set_par_traversal(bool b) { _par_traversal_in_progress = b; }
ysr@1280 150 GrowableArray<OopOrNarrowOopStar>** _new_refs;
ysr@1280 151 template <class T> void new_refs_iterate_work(OopClosure* cl);
ysr@1280 152 void new_refs_iterate(OopClosure* cl) {
ysr@1280 153 if (UseCompressedOops) {
ysr@1280 154 new_refs_iterate_work<narrowOop>(cl);
ysr@1280 155 } else {
ysr@1280 156 new_refs_iterate_work<oop>(cl);
ysr@1280 157 }
ysr@1280 158 }
ysr@1280 159
johnc@1325 160 // The routine that performs the actual work of refining a dirty
johnc@1325 161 // card.
johnc@1325 162 void concurrentRefineOneCard_impl(jbyte* card_ptr, int worker_i);
johnc@1325 163
ysr@1280 164 protected:
ysr@1280 165 template <class T> void write_ref_nv(HeapRegion* from, T* p);
ysr@1280 166 template <class T> void par_write_ref_nv(HeapRegion* from, T* p, int tid);
ysr@777 167
ysr@777 168 public:
ysr@777 169 // This is called to reset dual hash tables after the gc pause
ysr@777 170 // is finished and the initial hash table is no longer being
ysr@777 171 // scanned.
ysr@777 172 void cleanupHRRS();
ysr@777 173
ysr@777 174 HRInto_G1RemSet(G1CollectedHeap* g1, CardTableModRefBS* ct_bs);
ysr@777 175 ~HRInto_G1RemSet();
ysr@777 176
ysr@777 177 void oops_into_collection_set_do(OopsInHeapRegionClosure* blk,
ysr@777 178 int worker_i);
ysr@777 179
ysr@777 180 void prepare_for_oops_into_collection_set_do();
ysr@777 181 void cleanup_after_oops_into_collection_set_do();
ysr@777 182 void scanRS(OopsInHeapRegionClosure* oc, int worker_i);
ysr@1280 183 template <class T> void scanNewRefsRS_work(OopsInHeapRegionClosure* oc, int worker_i);
ysr@1280 184 void scanNewRefsRS(OopsInHeapRegionClosure* oc, int worker_i) {
ysr@1280 185 if (UseCompressedOops) {
ysr@1280 186 scanNewRefsRS_work<narrowOop>(oc, worker_i);
ysr@1280 187 } else {
ysr@1280 188 scanNewRefsRS_work<oop>(oc, worker_i);
ysr@1280 189 }
ysr@1280 190 }
ysr@777 191 void updateRS(int worker_i);
ysr@777 192 HeapRegion* calculateStartRegion(int i);
ysr@777 193
ysr@777 194 HRInto_G1RemSet* as_HRInto_G1RemSet() { return this; }
ysr@777 195
ysr@777 196 CardTableModRefBS* ct_bs() { return _ct_bs; }
ysr@777 197 size_t cardsScanned() { return _total_cards_scanned; }
ysr@777 198
ysr@777 199 // Record, if necessary, the fact that *p (where "p" is in region "from",
ysr@777 200 // which is required to be non-NULL) has changed to a new non-NULL value.
ysr@1280 201 // [Below the virtual version calls a non-virtual protected
ysr@1280 202 // workhorse that is templatified for narrow vs wide oop.]
ysr@1280 203 inline void write_ref(HeapRegion* from, oop* p) {
ysr@1280 204 write_ref_nv(from, p);
ysr@1280 205 }
ysr@1280 206 inline void write_ref(HeapRegion* from, narrowOop* p) {
ysr@1280 207 write_ref_nv(from, p);
ysr@1280 208 }
ysr@1280 209 inline void par_write_ref(HeapRegion* from, oop* p, int tid) {
ysr@1280 210 par_write_ref_nv(from, p, tid);
ysr@1280 211 }
ysr@1280 212 inline void par_write_ref(HeapRegion* from, narrowOop* p, int tid) {
ysr@1280 213 par_write_ref_nv(from, p, tid);
ysr@1280 214 }
ysr@777 215
ysr@1280 216 bool self_forwarded(oop obj);
ysr@777 217
ysr@777 218 void scrub(BitMap* region_bm, BitMap* card_bm);
ysr@777 219 void scrub_par(BitMap* region_bm, BitMap* card_bm,
ysr@777 220 int worker_num, int claim_val);
ysr@777 221
ysr@777 222 virtual void concurrentRefineOneCard(jbyte* card_ptr, int worker_i);
ysr@777 223
ysr@777 224 virtual void print_summary_info();
ysr@777 225 virtual void prepare_for_verify();
ysr@777 226 };
ysr@777 227
ysr@777 228 #define G1_REM_SET_LOGGING 0
ysr@777 229
ysr@777 230 class CountNonCleanMemRegionClosure: public MemRegionClosure {
ysr@777 231 G1CollectedHeap* _g1;
ysr@777 232 int _n;
ysr@777 233 HeapWord* _start_first;
ysr@777 234 public:
ysr@777 235 CountNonCleanMemRegionClosure(G1CollectedHeap* g1) :
ysr@777 236 _g1(g1), _n(0), _start_first(NULL)
ysr@777 237 {}
ysr@777 238 void do_MemRegion(MemRegion mr);
ysr@777 239 int n() { return _n; };
ysr@777 240 HeapWord* start_first() { return _start_first; }
ysr@777 241 };
apetrusenko@1061 242
apetrusenko@1061 243 class UpdateRSOopClosure: public OopClosure {
apetrusenko@1061 244 HeapRegion* _from;
apetrusenko@1061 245 HRInto_G1RemSet* _rs;
apetrusenko@1061 246 int _worker_i;
ysr@1280 247
ysr@1280 248 template <class T> void do_oop_work(T* p);
ysr@1280 249
apetrusenko@1061 250 public:
apetrusenko@1061 251 UpdateRSOopClosure(HRInto_G1RemSet* rs, int worker_i = 0) :
apetrusenko@1061 252 _from(NULL), _rs(rs), _worker_i(worker_i) {
apetrusenko@1061 253 guarantee(_rs != NULL, "Requires an HRIntoG1RemSet");
apetrusenko@1061 254 }
apetrusenko@1061 255
apetrusenko@1061 256 void set_from(HeapRegion* from) {
apetrusenko@1061 257 assert(from != NULL, "from region must be non-NULL");
apetrusenko@1061 258 _from = from;
apetrusenko@1061 259 }
apetrusenko@1061 260
ysr@1280 261 virtual void do_oop(narrowOop* p) { do_oop_work(p); }
ysr@1280 262 virtual void do_oop(oop* p) { do_oop_work(p); }
apetrusenko@1061 263
apetrusenko@1061 264 // Override: this closure is idempotent.
apetrusenko@1061 265 // bool idempotent() { return true; }
apetrusenko@1061 266 bool apply_to_weak_ref_discovered_field() { return true; }
apetrusenko@1061 267 };

mercurial