1 /*
  2  * Copyright (c) 2017, 2020, Red Hat, Inc. All rights reserved.
  3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  4  *
  5  * This code is free software; you can redistribute it and/or modify it
  6  * under the terms of the GNU General Public License version 2 only, as
  7  * published by the Free Software Foundation.
  8  *
  9  * This code is distributed in the hope that it will be useful, but WITHOUT
 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).
 14  *
 15  * You should have received a copy of the GNU General Public License version
 16  * 2 along with this work; if not, write to the Free Software Foundation,
 17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 18  *
 19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 20  * or visit www.oracle.com if you need additional information or have any
 21  * questions.
 22  *
 23  */
 24 
 25 #ifndef SHARE_GC_SHENANDOAH_SHENANDOAHVERIFIER_HPP
 26 #define SHARE_GC_SHENANDOAH_SHENANDOAHVERIFIER_HPP
 27 
 28 #include "gc/shared/markBitMap.hpp"
 29 #include "gc/shenandoah/shenandoahRootVerifier.hpp"
 30 #include "memory/allocation.hpp"
 31 #include "oops/oopsHierarchy.hpp"
 32 #include "utilities/stack.hpp"
 33 
 34 class ShenandoahHeap;
 35 
 36 #ifdef _WINDOWS
 37 #pragma warning( disable : 4522 )
 38 #endif
 39 
 40 class ShenandoahVerifierTask {
 41 public:
 42   ShenandoahVerifierTask(oop o = NULL, int idx = 0): _obj(o) { }
 43   ShenandoahVerifierTask(oop o, size_t idx): _obj(o) { }
 44   // Trivially copyable.
 45 
 46   inline oop obj()  const { return _obj; }
 47 
 48 private:
 49   oop _obj;
 50 };
 51 
 52 typedef Stack<ShenandoahVerifierTask, mtGC> ShenandoahVerifierStack;
 53 typedef volatile juint ShenandoahLivenessData;
 54 
 55 class ShenandoahVerifier : public CHeapObj<mtGC> {
 56 private:
 57   ShenandoahHeap* _heap;
 58   MarkBitMap* _verification_bit_map;
 59 public:
 60   typedef enum {
 61     // Disable marked objects verification.
 62     _verify_marked_disable,
 63 
 64     // Objects should be marked in "next" bitmap.
 65     _verify_marked_incomplete,
 66 
 67     // Objects should be marked in "complete" bitmap.
 68     _verify_marked_complete,
 69 
 70     // Objects should be marked in "complete" bitmap, except j.l.r.Reference referents, which
 71     // may be dangling after marking but before conc-weakrefs-processing.
 72     _verify_marked_complete_except_references
 73   } VerifyMarked;
 74 
 75   typedef enum {
 76     // Disable forwarded objects verification.
 77     _verify_forwarded_disable,
 78 
 79     // Objects should not have forwardees.
 80     _verify_forwarded_none,
 81 
 82     // Objects may have forwardees.
 83     _verify_forwarded_allow
 84   } VerifyForwarded;
 85 
 86   typedef enum {
 87     // Disable collection set verification.
 88     _verify_cset_disable,
 89 
 90     // Should have no references to cset.
 91     _verify_cset_none,
 92 
 93     // May have references to cset, all should be forwarded.
 94     // Note: Allowing non-forwarded references to cset is equivalent
 95     // to _verify_cset_disable.
 96     _verify_cset_forwarded
 97   } VerifyCollectionSet;
 98 
 99   typedef enum {
100     // Disable liveness verification
101     _verify_liveness_disable,
102 
103     // All objects should belong to live regions
104     _verify_liveness_conservative,
105 
106     // All objects should belong to live regions,
107     // and liveness data should be accurate
108     _verify_liveness_complete
109   } VerifyLiveness;
110 
111   typedef enum {
112     // Disable region verification
113     _verify_regions_disable,
114 
115     // No trash regions allowed
116     _verify_regions_notrash,
117 
118     // No collection set regions allowed
119     _verify_regions_nocset,
120 
121     // No trash and no cset regions allowed
122     _verify_regions_notrash_nocset
123   } VerifyRegions;
124 
125   typedef enum {
126     // Disable gc-state verification
127     _verify_gcstate_disable,
128 
129     // Nothing is in progress, no forwarded objects
130     _verify_gcstate_stable,
131 
132     // Nothing is in progress, no forwarded objects, weak roots handling
133     _verify_gcstate_stable_weakroots,
134 
135     // Nothing is in progress, some objects are forwarded
136     _verify_gcstate_forwarded,
137 
138     // Evacuation is in progress, some objects are forwarded
139     _verify_gcstate_evacuation
140   } VerifyGCState;
141 
142   struct VerifyOptions {
143     VerifyForwarded     _verify_forwarded;
144     VerifyMarked        _verify_marked;
145     VerifyCollectionSet _verify_cset;
146     VerifyLiveness      _verify_liveness;
147     VerifyRegions       _verify_regions;
148     VerifyGCState       _verify_gcstate;
149 
150     VerifyOptions(VerifyForwarded verify_forwarded,
151                   VerifyMarked verify_marked,
152                   VerifyCollectionSet verify_collection_set,
153                   VerifyLiveness verify_liveness,
154                   VerifyRegions verify_regions,
155                   VerifyGCState verify_gcstate) :
156             _verify_forwarded(verify_forwarded), _verify_marked(verify_marked),
157             _verify_cset(verify_collection_set),
158             _verify_liveness(verify_liveness), _verify_regions(verify_regions),
159             _verify_gcstate(verify_gcstate) {}
160   };
161 
162 private:
163   void verify_at_safepoint(const char *label,
164                            VerifyForwarded forwarded,
165                            VerifyMarked marked,
166                            VerifyCollectionSet cset,
167                            VerifyLiveness liveness,
168                            VerifyRegions regions,
169                            VerifyGCState gcstate);
170 
171 public:
172   ShenandoahVerifier(ShenandoahHeap* heap, MarkBitMap* verification_bitmap) :
173           _heap(heap), _verification_bit_map(verification_bitmap) {};
174 
175   void verify_before_concmark();
176   void verify_after_concmark();
177   void verify_before_evacuation();
178   void verify_during_evacuation();
179   void verify_after_evacuation();
180   void verify_before_updaterefs();
181   void verify_after_updaterefs();
182   void verify_before_fullgc();
183   void verify_after_fullgc();
184   void verify_after_degenerated();
185   void verify_generic(VerifyOption option);
186 
187   // Roots should only contain to-space oops
188   void verify_roots_in_to_space();
189 
190   void verify_roots_no_forwarded();
191 };
192 
193 #endif // SHARE_GC_SHENANDOAH_SHENANDOAHVERIFIER_HPP