Tue, 19 May 2015 15:49:27 +0200
8061715: gc/g1/TestShrinkAuxiliaryData15.java fails with java.lang.RuntimeException: heap decommit failed - after > before
Summary: added WhiteBox methods to count regions and exact aux data sizes
Reviewed-by: jwilhelm, brutisso
1 /*
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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5 * This code is free software; you can redistribute it and/or modify it
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10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
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25 #ifndef SHARE_VM_GC_IMPLEMENTATION_G1_G1REMSET_HPP
26 #define SHARE_VM_GC_IMPLEMENTATION_G1_G1REMSET_HPP
28 #include "gc_implementation/g1/g1RemSetSummary.hpp"
30 // A G1RemSet provides ways of iterating over pointers into a selected
31 // collection set.
33 class G1CollectedHeap;
34 class CardTableModRefBarrierSet;
35 class ConcurrentG1Refine;
36 class G1ParPushHeapRSClosure;
38 // A G1RemSet in which each heap region has a rem set that records the
39 // external heap references into it. Uses a mod ref bs to track updates,
40 // so that they can be used to update the individual region remsets.
42 class G1RemSet: public CHeapObj<mtGC> {
43 private:
44 G1RemSetSummary _prev_period_summary;
45 protected:
46 G1CollectedHeap* _g1;
47 size_t _conc_refine_cards;
48 uint n_workers();
50 protected:
51 enum SomePrivateConstants {
52 UpdateRStoMergeSync = 0,
53 MergeRStoDoDirtySync = 1,
54 DoDirtySync = 2,
55 LastSync = 3,
57 SeqTask = 0,
58 NumSeqTasks = 1
59 };
61 CardTableModRefBS* _ct_bs;
62 G1CollectorPolicy* _g1p;
64 ConcurrentG1Refine* _cg1r;
66 size_t* _cards_scanned;
67 size_t _total_cards_scanned;
69 // Used for caching the closure that is responsible for scanning
70 // references into the collection set.
71 G1ParPushHeapRSClosure** _cset_rs_update_cl;
73 // Print the given summary info
74 virtual void print_summary_info(G1RemSetSummary * summary, const char * header = NULL);
75 public:
76 // This is called to reset dual hash tables after the gc pause
77 // is finished and the initial hash table is no longer being
78 // scanned.
79 void cleanupHRRS();
81 G1RemSet(G1CollectedHeap* g1, CardTableModRefBS* ct_bs);
82 ~G1RemSet();
84 // Invoke "blk->do_oop" on all pointers into the collection set
85 // from objects in regions outside the collection set (having
86 // invoked "blk->set_region" to set the "from" region correctly
87 // beforehand.)
88 //
89 // Invoke code_root_cl->do_code_blob on the unmarked nmethods
90 // on the strong code roots list for each region in the
91 // collection set.
92 //
93 // The "worker_i" param is for the parallel case where the id
94 // of the worker thread calling this function can be helpful in
95 // partitioning the work to be done. It should be the same as
96 // the "i" passed to the calling thread's work(i) function.
97 // In the sequential case this param will be ignored.
98 void oops_into_collection_set_do(G1ParPushHeapRSClosure* blk,
99 CodeBlobClosure* code_root_cl,
100 uint worker_i);
102 // Prepare for and cleanup after an oops_into_collection_set_do
103 // call. Must call each of these once before and after (in sequential
104 // code) any threads call oops_into_collection_set_do. (This offers an
105 // opportunity to sequential setup and teardown of structures needed by a
106 // parallel iteration over the CS's RS.)
107 void prepare_for_oops_into_collection_set_do();
108 void cleanup_after_oops_into_collection_set_do();
110 void scanRS(G1ParPushHeapRSClosure* oc,
111 CodeBlobClosure* code_root_cl,
112 uint worker_i);
114 void updateRS(DirtyCardQueue* into_cset_dcq, uint worker_i);
116 CardTableModRefBS* ct_bs() { return _ct_bs; }
117 size_t cardsScanned() { return _total_cards_scanned; }
119 // Record, if necessary, the fact that *p (where "p" is in region "from",
120 // which is required to be non-NULL) has changed to a new non-NULL value.
121 template <class T> void write_ref(HeapRegion* from, T* p);
122 template <class T> void par_write_ref(HeapRegion* from, T* p, int tid);
124 // Requires "region_bm" and "card_bm" to be bitmaps with 1 bit per region
125 // or card, respectively, such that a region or card with a corresponding
126 // 0 bit contains no part of any live object. Eliminates any remembered
127 // set entries that correspond to dead heap ranges.
128 void scrub(BitMap* region_bm, BitMap* card_bm);
130 // Like the above, but assumes is called in parallel: "worker_num" is the
131 // parallel thread id of the current thread, and "claim_val" is the
132 // value that should be used to claim heap regions.
133 void scrub_par(BitMap* region_bm, BitMap* card_bm,
134 uint worker_num, int claim_val);
136 // Refine the card corresponding to "card_ptr".
137 // If check_for_refs_into_cset is true, a true result is returned
138 // if the given card contains oops that have references into the
139 // current collection set.
140 virtual bool refine_card(jbyte* card_ptr,
141 uint worker_i,
142 bool check_for_refs_into_cset);
144 // Print accumulated summary info from the start of the VM.
145 virtual void print_summary_info();
147 // Print accumulated summary info from the last time called.
148 virtual void print_periodic_summary_info(const char* header);
150 // Prepare remembered set for verification.
151 virtual void prepare_for_verify();
153 size_t conc_refine_cards() const {
154 return _conc_refine_cards;
155 }
156 };
158 class CountNonCleanMemRegionClosure: public MemRegionClosure {
159 G1CollectedHeap* _g1;
160 int _n;
161 HeapWord* _start_first;
162 public:
163 CountNonCleanMemRegionClosure(G1CollectedHeap* g1) :
164 _g1(g1), _n(0), _start_first(NULL)
165 {}
166 void do_MemRegion(MemRegion mr);
167 int n() { return _n; };
168 HeapWord* start_first() { return _start_first; }
169 };
171 class UpdateRSOopClosure: public ExtendedOopClosure {
172 HeapRegion* _from;
173 G1RemSet* _rs;
174 uint _worker_i;
176 template <class T> void do_oop_work(T* p);
178 public:
179 UpdateRSOopClosure(G1RemSet* rs, uint worker_i = 0) :
180 _from(NULL), _rs(rs), _worker_i(worker_i)
181 {}
183 void set_from(HeapRegion* from) {
184 assert(from != NULL, "from region must be non-NULL");
185 _from = from;
186 }
188 virtual void do_oop(narrowOop* p) { do_oop_work(p); }
189 virtual void do_oop(oop* p) { do_oop_work(p); }
191 // Override: this closure is idempotent.
192 // bool idempotent() { return true; }
193 bool apply_to_weak_ref_discovered_field() { return true; }
194 };
196 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1REMSET_HPP