Wed, 23 Sep 2009 23:56:15 -0700
Merge
duke@435 | 1 | /* |
xdono@631 | 2 | * Copyright 1997-2008 Sun Microsystems, Inc. All Rights Reserved. |
duke@435 | 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
duke@435 | 4 | * |
duke@435 | 5 | * This code is free software; you can redistribute it and/or modify it |
duke@435 | 6 | * under the terms of the GNU General Public License version 2 only, as |
duke@435 | 7 | * published by the Free Software Foundation. |
duke@435 | 8 | * |
duke@435 | 9 | * This code is distributed in the hope that it will be useful, but WITHOUT |
duke@435 | 10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
duke@435 | 11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
duke@435 | 12 | * version 2 for more details (a copy is included in the LICENSE file that |
duke@435 | 13 | * accompanied this code). |
duke@435 | 14 | * |
duke@435 | 15 | * You should have received a copy of the GNU General Public License version |
duke@435 | 16 | * 2 along with this work; if not, write to the Free Software Foundation, |
duke@435 | 17 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
duke@435 | 18 | * |
duke@435 | 19 | * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
duke@435 | 20 | * CA 95054 USA or visit www.sun.com if you need additional information or |
duke@435 | 21 | * have any questions. |
duke@435 | 22 | * |
duke@435 | 23 | */ |
duke@435 | 24 | |
duke@435 | 25 | // The following classes are C++ `closures` for iterating over objects, roots and spaces |
duke@435 | 26 | |
jrose@1424 | 27 | class CodeBlob; |
duke@435 | 28 | class ReferenceProcessor; |
ysr@1376 | 29 | class DataLayout; |
duke@435 | 30 | |
ysr@777 | 31 | // Closure provides abortability. |
ysr@777 | 32 | |
ysr@777 | 33 | class Closure : public StackObj { |
ysr@777 | 34 | protected: |
ysr@777 | 35 | bool _abort; |
ysr@777 | 36 | void set_abort() { _abort = true; } |
ysr@777 | 37 | public: |
ysr@777 | 38 | Closure() : _abort(false) {} |
ysr@777 | 39 | // A subtype can use this mechanism to indicate to some iterator mapping |
ysr@777 | 40 | // functions that the iteration should cease. |
ysr@777 | 41 | bool abort() { return _abort; } |
ysr@777 | 42 | void clear_abort() { _abort = false; } |
ysr@777 | 43 | }; |
ysr@777 | 44 | |
duke@435 | 45 | // OopClosure is used for iterating through roots (oop*) |
duke@435 | 46 | |
ysr@777 | 47 | class OopClosure : public Closure { |
duke@435 | 48 | public: |
duke@435 | 49 | ReferenceProcessor* _ref_processor; |
duke@435 | 50 | OopClosure(ReferenceProcessor* rp) : _ref_processor(rp) { } |
duke@435 | 51 | OopClosure() : _ref_processor(NULL) { } |
duke@435 | 52 | virtual void do_oop(oop* o) = 0; |
duke@435 | 53 | virtual void do_oop_v(oop* o) { do_oop(o); } |
coleenp@548 | 54 | virtual void do_oop(narrowOop* o) = 0; |
coleenp@548 | 55 | virtual void do_oop_v(narrowOop* o) { do_oop(o); } |
duke@435 | 56 | |
duke@435 | 57 | // In support of post-processing of weak links of KlassKlass objects; |
duke@435 | 58 | // see KlassKlass::oop_oop_iterate(). |
jmasa@1370 | 59 | |
jmasa@1370 | 60 | virtual const bool should_remember_klasses() const { |
jmasa@1370 | 61 | assert(!must_remember_klasses(), "Should have overriden this method."); |
jmasa@1370 | 62 | return false; |
jmasa@1370 | 63 | } |
jmasa@1370 | 64 | |
duke@435 | 65 | virtual void remember_klass(Klass* k) { /* do nothing */ } |
duke@435 | 66 | |
ysr@1376 | 67 | // In support of post-processing of weak references in |
ysr@1376 | 68 | // ProfileData (MethodDataOop) objects; see, for example, |
ysr@1376 | 69 | // VirtualCallData::oop_iterate(). |
ysr@1376 | 70 | virtual const bool should_remember_mdo() const { return false; } |
ysr@1376 | 71 | virtual void remember_mdo(DataLayout* v) { /* do nothing */ } |
ysr@1376 | 72 | |
duke@435 | 73 | // If "true", invoke on nmethods (when scanning compiled frames). |
duke@435 | 74 | virtual const bool do_nmethods() const { return false; } |
duke@435 | 75 | |
duke@435 | 76 | // The methods below control how object iterations invoking this closure |
duke@435 | 77 | // should be performed: |
duke@435 | 78 | |
duke@435 | 79 | // If "true", invoke on header klass field. |
duke@435 | 80 | bool do_header() { return true; } // Note that this is non-virtual. |
duke@435 | 81 | // Controls how prefetching is done for invocations of this closure. |
duke@435 | 82 | Prefetch::style prefetch_style() { // Note that this is non-virtual. |
duke@435 | 83 | return Prefetch::do_none; |
duke@435 | 84 | } |
ysr@777 | 85 | |
ysr@777 | 86 | // True iff this closure may be safely applied more than once to an oop |
ysr@777 | 87 | // location without an intervening "major reset" (like the end of a GC). |
ysr@777 | 88 | virtual bool idempotent() { return false; } |
ysr@777 | 89 | virtual bool apply_to_weak_ref_discovered_field() { return false; } |
jmasa@1370 | 90 | |
jmasa@1370 | 91 | #ifdef ASSERT |
jmasa@1370 | 92 | static bool _must_remember_klasses; |
jmasa@1370 | 93 | static bool must_remember_klasses(); |
jmasa@1370 | 94 | static void set_must_remember_klasses(bool v); |
jmasa@1370 | 95 | #endif |
duke@435 | 96 | }; |
duke@435 | 97 | |
duke@435 | 98 | // ObjectClosure is used for iterating through an object space |
duke@435 | 99 | |
ysr@777 | 100 | class ObjectClosure : public Closure { |
duke@435 | 101 | public: |
duke@435 | 102 | // Called for each object. |
duke@435 | 103 | virtual void do_object(oop obj) = 0; |
duke@435 | 104 | }; |
duke@435 | 105 | |
duke@435 | 106 | |
duke@435 | 107 | class BoolObjectClosure : public ObjectClosure { |
duke@435 | 108 | public: |
duke@435 | 109 | virtual bool do_object_b(oop obj) = 0; |
duke@435 | 110 | }; |
duke@435 | 111 | |
duke@435 | 112 | // Applies an oop closure to all ref fields in objects iterated over in an |
duke@435 | 113 | // object iteration. |
duke@435 | 114 | class ObjectToOopClosure: public ObjectClosure { |
duke@435 | 115 | OopClosure* _cl; |
duke@435 | 116 | public: |
duke@435 | 117 | void do_object(oop obj); |
duke@435 | 118 | ObjectToOopClosure(OopClosure* cl) : _cl(cl) {} |
duke@435 | 119 | }; |
duke@435 | 120 | |
duke@435 | 121 | // A version of ObjectClosure with "memory" (see _previous_address below) |
duke@435 | 122 | class UpwardsObjectClosure: public BoolObjectClosure { |
duke@435 | 123 | HeapWord* _previous_address; |
duke@435 | 124 | public: |
duke@435 | 125 | UpwardsObjectClosure() : _previous_address(NULL) { } |
duke@435 | 126 | void set_previous(HeapWord* addr) { _previous_address = addr; } |
duke@435 | 127 | HeapWord* previous() { return _previous_address; } |
duke@435 | 128 | // A return value of "true" can be used by the caller to decide |
duke@435 | 129 | // if this object's end should *NOT* be recorded in |
duke@435 | 130 | // _previous_address above. |
duke@435 | 131 | virtual bool do_object_bm(oop obj, MemRegion mr) = 0; |
duke@435 | 132 | }; |
duke@435 | 133 | |
duke@435 | 134 | // A version of ObjectClosure that is expected to be robust |
duke@435 | 135 | // in the face of possibly uninitialized objects. |
duke@435 | 136 | class ObjectClosureCareful : public ObjectClosure { |
duke@435 | 137 | public: |
duke@435 | 138 | virtual size_t do_object_careful_m(oop p, MemRegion mr) = 0; |
duke@435 | 139 | virtual size_t do_object_careful(oop p) = 0; |
duke@435 | 140 | }; |
duke@435 | 141 | |
duke@435 | 142 | // The following are used in CompactibleFreeListSpace and |
duke@435 | 143 | // ConcurrentMarkSweepGeneration. |
duke@435 | 144 | |
duke@435 | 145 | // Blk closure (abstract class) |
duke@435 | 146 | class BlkClosure : public StackObj { |
duke@435 | 147 | public: |
duke@435 | 148 | virtual size_t do_blk(HeapWord* addr) = 0; |
duke@435 | 149 | }; |
duke@435 | 150 | |
duke@435 | 151 | // A version of BlkClosure that is expected to be robust |
duke@435 | 152 | // in the face of possibly uninitialized objects. |
duke@435 | 153 | class BlkClosureCareful : public BlkClosure { |
duke@435 | 154 | public: |
duke@435 | 155 | size_t do_blk(HeapWord* addr) { |
duke@435 | 156 | guarantee(false, "call do_blk_careful instead"); |
duke@435 | 157 | return 0; |
duke@435 | 158 | } |
duke@435 | 159 | virtual size_t do_blk_careful(HeapWord* addr) = 0; |
duke@435 | 160 | }; |
duke@435 | 161 | |
duke@435 | 162 | // SpaceClosure is used for iterating over spaces |
duke@435 | 163 | |
duke@435 | 164 | class Space; |
duke@435 | 165 | class CompactibleSpace; |
duke@435 | 166 | |
duke@435 | 167 | class SpaceClosure : public StackObj { |
duke@435 | 168 | public: |
duke@435 | 169 | // Called for each space |
duke@435 | 170 | virtual void do_space(Space* s) = 0; |
duke@435 | 171 | }; |
duke@435 | 172 | |
duke@435 | 173 | class CompactibleSpaceClosure : public StackObj { |
duke@435 | 174 | public: |
duke@435 | 175 | // Called for each compactible space |
duke@435 | 176 | virtual void do_space(CompactibleSpace* s) = 0; |
duke@435 | 177 | }; |
duke@435 | 178 | |
duke@435 | 179 | |
jrose@1424 | 180 | // CodeBlobClosure is used for iterating through code blobs |
jrose@1424 | 181 | // in the code cache or on thread stacks |
jrose@1424 | 182 | |
jrose@1424 | 183 | class CodeBlobClosure : public Closure { |
jrose@1424 | 184 | public: |
jrose@1424 | 185 | // Called for each code blob. |
jrose@1424 | 186 | virtual void do_code_blob(CodeBlob* cb) = 0; |
jrose@1424 | 187 | }; |
jrose@1424 | 188 | |
jrose@1424 | 189 | |
jrose@1424 | 190 | class MarkingCodeBlobClosure : public CodeBlobClosure { |
jrose@1424 | 191 | public: |
jrose@1424 | 192 | // Called for each code blob, but at most once per unique blob. |
jrose@1424 | 193 | virtual void do_newly_marked_nmethod(CodeBlob* cb) = 0; |
jrose@1424 | 194 | |
jrose@1424 | 195 | virtual void do_code_blob(CodeBlob* cb); |
jrose@1424 | 196 | // = { if (!nmethod(cb)->test_set_oops_do_mark()) do_newly_marked_nmethod(cb); } |
jrose@1424 | 197 | |
jrose@1424 | 198 | class MarkScope : public StackObj { |
jrose@1424 | 199 | protected: |
jrose@1424 | 200 | bool _active; |
jrose@1424 | 201 | public: |
jrose@1424 | 202 | MarkScope(bool activate = true); |
jrose@1424 | 203 | // = { if (active) nmethod::oops_do_marking_prologue(); } |
jrose@1424 | 204 | ~MarkScope(); |
jrose@1424 | 205 | // = { if (active) nmethod::oops_do_marking_epilogue(); } |
jrose@1424 | 206 | }; |
jrose@1424 | 207 | }; |
jrose@1424 | 208 | |
jrose@1424 | 209 | |
jrose@1424 | 210 | // Applies an oop closure to all ref fields in code blobs |
jrose@1424 | 211 | // iterated over in an object iteration. |
jrose@1424 | 212 | class CodeBlobToOopClosure: public MarkingCodeBlobClosure { |
jrose@1424 | 213 | OopClosure* _cl; |
jrose@1424 | 214 | bool _do_marking; |
jrose@1424 | 215 | public: |
jrose@1424 | 216 | virtual void do_newly_marked_nmethod(CodeBlob* cb); |
jrose@1424 | 217 | // = { cb->oops_do(_cl); } |
jrose@1424 | 218 | virtual void do_code_blob(CodeBlob* cb); |
jrose@1424 | 219 | // = { if (_do_marking) super::do_code_blob(cb); else cb->oops_do(_cl); } |
jrose@1424 | 220 | CodeBlobToOopClosure(OopClosure* cl, bool do_marking) |
jrose@1424 | 221 | : _cl(cl), _do_marking(do_marking) {} |
jrose@1424 | 222 | }; |
jrose@1424 | 223 | |
jrose@1424 | 224 | |
duke@435 | 225 | |
duke@435 | 226 | // MonitorClosure is used for iterating over monitors in the monitors cache |
duke@435 | 227 | |
duke@435 | 228 | class ObjectMonitor; |
duke@435 | 229 | |
duke@435 | 230 | class MonitorClosure : public StackObj { |
duke@435 | 231 | public: |
duke@435 | 232 | // called for each monitor in cache |
duke@435 | 233 | virtual void do_monitor(ObjectMonitor* m) = 0; |
duke@435 | 234 | }; |
duke@435 | 235 | |
duke@435 | 236 | // A closure that is applied without any arguments. |
duke@435 | 237 | class VoidClosure : public StackObj { |
duke@435 | 238 | public: |
duke@435 | 239 | // I would have liked to declare this a pure virtual, but that breaks |
duke@435 | 240 | // in mysterious ways, for unknown reasons. |
duke@435 | 241 | virtual void do_void(); |
duke@435 | 242 | }; |
duke@435 | 243 | |
duke@435 | 244 | |
duke@435 | 245 | // YieldClosure is intended for use by iteration loops |
duke@435 | 246 | // to incrementalize their work, allowing interleaving |
duke@435 | 247 | // of an interruptable task so as to allow other |
duke@435 | 248 | // threads to run (which may not otherwise be able to access |
duke@435 | 249 | // exclusive resources, for instance). Additionally, the |
duke@435 | 250 | // closure also allows for aborting an ongoing iteration |
duke@435 | 251 | // by means of checking the return value from the polling |
duke@435 | 252 | // call. |
duke@435 | 253 | class YieldClosure : public StackObj { |
duke@435 | 254 | public: |
duke@435 | 255 | virtual bool should_return() = 0; |
duke@435 | 256 | }; |
duke@435 | 257 | |
duke@435 | 258 | // Abstract closure for serializing data (read or write). |
duke@435 | 259 | |
duke@435 | 260 | class SerializeOopClosure : public OopClosure { |
duke@435 | 261 | public: |
duke@435 | 262 | // Return bool indicating whether closure implements read or write. |
duke@435 | 263 | virtual bool reading() const = 0; |
duke@435 | 264 | |
duke@435 | 265 | // Read/write the int pointed to by i. |
duke@435 | 266 | virtual void do_int(int* i) = 0; |
duke@435 | 267 | |
duke@435 | 268 | // Read/write the size_t pointed to by i. |
duke@435 | 269 | virtual void do_size_t(size_t* i) = 0; |
duke@435 | 270 | |
duke@435 | 271 | // Read/write the void pointer pointed to by p. |
duke@435 | 272 | virtual void do_ptr(void** p) = 0; |
duke@435 | 273 | |
duke@435 | 274 | // Read/write the HeapWord pointer pointed to be p. |
duke@435 | 275 | virtual void do_ptr(HeapWord** p) = 0; |
duke@435 | 276 | |
duke@435 | 277 | // Read/write the region specified. |
duke@435 | 278 | virtual void do_region(u_char* start, size_t size) = 0; |
duke@435 | 279 | |
duke@435 | 280 | // Check/write the tag. If reading, then compare the tag against |
duke@435 | 281 | // the passed in value and fail is they don't match. This allows |
duke@435 | 282 | // for verification that sections of the serialized data are of the |
duke@435 | 283 | // correct length. |
duke@435 | 284 | virtual void do_tag(int tag) = 0; |
duke@435 | 285 | }; |
jmasa@1370 | 286 | |
jmasa@1370 | 287 | #ifdef ASSERT |
jmasa@1370 | 288 | // This class is used to flag phases of a collection that |
jmasa@1370 | 289 | // can unload classes and which should override the |
jmasa@1370 | 290 | // should_remember_klasses() and remember_klass() of OopClosure. |
jmasa@1370 | 291 | // The _must_remember_klasses is set in the contructor and restored |
jmasa@1370 | 292 | // in the destructor. _must_remember_klasses is checked in assertions |
jmasa@1370 | 293 | // in the OopClosure implementations of should_remember_klasses() and |
jmasa@1370 | 294 | // remember_klass() and the expectation is that the OopClosure |
jmasa@1370 | 295 | // implementation should not be in use if _must_remember_klasses is set. |
jmasa@1370 | 296 | // Instances of RememberKlassesChecker can be place in |
jmasa@1370 | 297 | // marking phases of collections which can do class unloading. |
jmasa@1370 | 298 | // RememberKlassesChecker can be passed "false" to turn off checking. |
jmasa@1370 | 299 | // It is used by CMS when CMS yields to a different collector. |
jmasa@1370 | 300 | class RememberKlassesChecker: StackObj { |
jmasa@1370 | 301 | bool _state; |
jmasa@1370 | 302 | bool _skip; |
jmasa@1370 | 303 | public: |
jmasa@1370 | 304 | RememberKlassesChecker(bool checking_on) : _state(false), _skip(false) { |
jmasa@1370 | 305 | _skip = !(ClassUnloading && !UseConcMarkSweepGC || |
jmasa@1370 | 306 | CMSClassUnloadingEnabled && UseConcMarkSweepGC); |
jmasa@1370 | 307 | if (_skip) { |
jmasa@1370 | 308 | return; |
jmasa@1370 | 309 | } |
jmasa@1370 | 310 | _state = OopClosure::must_remember_klasses(); |
jmasa@1370 | 311 | OopClosure::set_must_remember_klasses(checking_on); |
jmasa@1370 | 312 | } |
jmasa@1370 | 313 | ~RememberKlassesChecker() { |
jmasa@1370 | 314 | if (_skip) { |
jmasa@1370 | 315 | return; |
jmasa@1370 | 316 | } |
jmasa@1370 | 317 | OopClosure::set_must_remember_klasses(_state); |
jmasa@1370 | 318 | } |
jmasa@1370 | 319 | }; |
jmasa@1370 | 320 | #endif // ASSERT |