Tue, 25 Mar 2014 17:07:36 -0700
Merge
1 /*
2 * Copyright (c) 2011, 2013, Oracle and/or its affiliates. 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.
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23 */
24 #ifndef SHARE_VM_MEMORY_METASPACE_HPP
25 #define SHARE_VM_MEMORY_METASPACE_HPP
27 #include "memory/allocation.hpp"
28 #include "memory/memRegion.hpp"
29 #include "memory/metaspaceChunkFreeListSummary.hpp"
30 #include "runtime/virtualspace.hpp"
31 #include "utilities/exceptions.hpp"
33 // Metaspace
34 //
35 // Metaspaces are Arenas for the VM's metadata.
36 // They are allocated one per class loader object, and one for the null
37 // bootstrap class loader
38 // Eventually for bootstrap loader we'll have a read-only section and read-write
39 // to write for DumpSharedSpaces and read for UseSharedSpaces
40 //
41 // block X ---+ +-------------------+
42 // | | Virtualspace |
43 // | | |
44 // | | |
45 // | |-------------------|
46 // | || Chunk |
47 // | || |
48 // | ||---------- |
49 // +------>||| block 0 | |
50 // ||---------- |
51 // ||| block 1 | |
52 // ||---------- |
53 // || |
54 // |-------------------|
55 // | |
56 // | |
57 // +-------------------+
58 //
60 class ChunkManager;
61 class ClassLoaderData;
62 class Metablock;
63 class Metachunk;
64 class MetaspaceTracer;
65 class MetaWord;
66 class Mutex;
67 class outputStream;
68 class SpaceManager;
69 class VirtualSpaceList;
71 // Metaspaces each have a SpaceManager and allocations
72 // are done by the SpaceManager. Allocations are done
73 // out of the current Metachunk. When the current Metachunk
74 // is exhausted, the SpaceManager gets a new one from
75 // the current VirtualSpace. When the VirtualSpace is exhausted
76 // the SpaceManager gets a new one. The SpaceManager
77 // also manages freelists of available Chunks.
78 //
79 // Currently the space manager maintains the list of
80 // virtual spaces and the list of chunks in use. Its
81 // allocate() method returns a block for use as a
82 // quantum of metadata.
84 class Metaspace : public CHeapObj<mtClass> {
85 friend class VMStructs;
86 friend class SpaceManager;
87 friend class VM_CollectForMetadataAllocation;
88 friend class MetaspaceGC;
89 friend class MetaspaceAux;
91 public:
92 enum MetadataType {
93 ClassType,
94 NonClassType,
95 MetadataTypeCount
96 };
97 enum MetaspaceType {
98 StandardMetaspaceType,
99 BootMetaspaceType,
100 ROMetaspaceType,
101 ReadWriteMetaspaceType,
102 AnonymousMetaspaceType,
103 ReflectionMetaspaceType
104 };
106 private:
107 void initialize(Mutex* lock, MetaspaceType type);
109 // Get the first chunk for a Metaspace. Used for
110 // special cases such as the boot class loader, reflection
111 // class loader and anonymous class loader.
112 Metachunk* get_initialization_chunk(MetadataType mdtype,
113 size_t chunk_word_size,
114 size_t chunk_bunch);
116 // Align up the word size to the allocation word size
117 static size_t align_word_size_up(size_t);
119 // Aligned size of the metaspace.
120 static size_t _compressed_class_space_size;
122 static size_t compressed_class_space_size() {
123 return _compressed_class_space_size;
124 }
126 static void set_compressed_class_space_size(size_t size) {
127 _compressed_class_space_size = size;
128 }
130 static size_t _first_chunk_word_size;
131 static size_t _first_class_chunk_word_size;
133 static size_t _commit_alignment;
134 static size_t _reserve_alignment;
136 SpaceManager* _vsm;
137 SpaceManager* vsm() const { return _vsm; }
139 SpaceManager* _class_vsm;
140 SpaceManager* class_vsm() const { return _class_vsm; }
142 // Allocate space for metadata of type mdtype. This is space
143 // within a Metachunk and is used by
144 // allocate(ClassLoaderData*, size_t, bool, MetadataType, TRAPS)
145 MetaWord* allocate(size_t word_size, MetadataType mdtype);
147 // Virtual Space lists for both classes and other metadata
148 static VirtualSpaceList* _space_list;
149 static VirtualSpaceList* _class_space_list;
151 static ChunkManager* _chunk_manager_metadata;
152 static ChunkManager* _chunk_manager_class;
154 static const MetaspaceTracer* _tracer;
156 public:
157 static VirtualSpaceList* space_list() { return _space_list; }
158 static VirtualSpaceList* class_space_list() { return _class_space_list; }
159 static VirtualSpaceList* get_space_list(MetadataType mdtype) {
160 assert(mdtype != MetadataTypeCount, "MetadaTypeCount can't be used as mdtype");
161 return mdtype == ClassType ? class_space_list() : space_list();
162 }
164 static ChunkManager* chunk_manager_metadata() { return _chunk_manager_metadata; }
165 static ChunkManager* chunk_manager_class() { return _chunk_manager_class; }
166 static ChunkManager* get_chunk_manager(MetadataType mdtype) {
167 assert(mdtype != MetadataTypeCount, "MetadaTypeCount can't be used as mdtype");
168 return mdtype == ClassType ? chunk_manager_class() : chunk_manager_metadata();
169 }
171 static const MetaspaceTracer* tracer() { return _tracer; }
173 private:
174 // This is used by DumpSharedSpaces only, where only _vsm is used. So we will
175 // maintain a single list for now.
176 void record_allocation(void* ptr, MetaspaceObj::Type type, size_t word_size);
178 #ifdef _LP64
179 static void set_narrow_klass_base_and_shift(address metaspace_base, address cds_base);
181 // Returns true if can use CDS with metaspace allocated as specified address.
182 static bool can_use_cds_with_metaspace_addr(char* metaspace_base, address cds_base);
184 static void allocate_metaspace_compressed_klass_ptrs(char* requested_addr, address cds_base);
186 static void initialize_class_space(ReservedSpace rs);
187 #endif
189 class AllocRecord : public CHeapObj<mtClass> {
190 public:
191 AllocRecord(address ptr, MetaspaceObj::Type type, int byte_size)
192 : _next(NULL), _ptr(ptr), _type(type), _byte_size(byte_size) {}
193 AllocRecord *_next;
194 address _ptr;
195 MetaspaceObj::Type _type;
196 int _byte_size;
197 };
199 AllocRecord * _alloc_record_head;
200 AllocRecord * _alloc_record_tail;
202 size_t class_chunk_size(size_t word_size);
204 public:
206 Metaspace(Mutex* lock, MetaspaceType type);
207 ~Metaspace();
209 static void ergo_initialize();
210 static void global_initialize();
212 static size_t first_chunk_word_size() { return _first_chunk_word_size; }
213 static size_t first_class_chunk_word_size() { return _first_class_chunk_word_size; }
215 static size_t reserve_alignment() { return _reserve_alignment; }
216 static size_t reserve_alignment_words() { return _reserve_alignment / BytesPerWord; }
217 static size_t commit_alignment() { return _commit_alignment; }
218 static size_t commit_alignment_words() { return _commit_alignment / BytesPerWord; }
220 char* bottom() const;
221 size_t used_words_slow(MetadataType mdtype) const;
222 size_t free_words_slow(MetadataType mdtype) const;
223 size_t capacity_words_slow(MetadataType mdtype) const;
225 size_t used_bytes_slow(MetadataType mdtype) const;
226 size_t capacity_bytes_slow(MetadataType mdtype) const;
228 static MetaWord* allocate(ClassLoaderData* loader_data, size_t word_size,
229 bool read_only, MetaspaceObj::Type type, TRAPS);
230 void deallocate(MetaWord* ptr, size_t byte_size, bool is_class);
232 MetaWord* expand_and_allocate(size_t size,
233 MetadataType mdtype);
235 bool contains(const void* ptr);
236 void dump(outputStream* const out) const;
238 // Free empty virtualspaces
239 static void purge(MetadataType mdtype);
240 static void purge();
242 static void report_metadata_oome(ClassLoaderData* loader_data, size_t word_size,
243 MetaspaceObj::Type type, MetadataType mdtype, TRAPS);
245 static const char* metadata_type_name(Metaspace::MetadataType mdtype);
247 void print_on(outputStream* st) const;
248 // Debugging support
249 void verify();
251 class AllocRecordClosure : public StackObj {
252 public:
253 virtual void doit(address ptr, MetaspaceObj::Type type, int byte_size) = 0;
254 };
256 void iterate(AllocRecordClosure *closure);
258 // Return TRUE only if UseCompressedClassPointers is True and DumpSharedSpaces is False.
259 static bool using_class_space() {
260 return NOT_LP64(false) LP64_ONLY(UseCompressedClassPointers && !DumpSharedSpaces);
261 }
263 static bool is_class_space_allocation(MetadataType mdType) {
264 return mdType == ClassType && using_class_space();
265 }
267 };
269 class MetaspaceAux : AllStatic {
270 static size_t free_chunks_total_words(Metaspace::MetadataType mdtype);
272 // These methods iterate over the classloader data graph
273 // for the given Metaspace type. These are slow.
274 static size_t used_bytes_slow(Metaspace::MetadataType mdtype);
275 static size_t free_bytes_slow(Metaspace::MetadataType mdtype);
276 static size_t capacity_bytes_slow(Metaspace::MetadataType mdtype);
277 static size_t capacity_bytes_slow();
279 // Running sum of space in all Metachunks that has been
280 // allocated to a Metaspace. This is used instead of
281 // iterating over all the classloaders. One for each
282 // type of Metadata
283 static size_t _allocated_capacity_words[Metaspace:: MetadataTypeCount];
284 // Running sum of space in all Metachunks that have
285 // are being used for metadata. One for each
286 // type of Metadata.
287 static size_t _allocated_used_words[Metaspace:: MetadataTypeCount];
289 public:
290 // Decrement and increment _allocated_capacity_words
291 static void dec_capacity(Metaspace::MetadataType type, size_t words);
292 static void inc_capacity(Metaspace::MetadataType type, size_t words);
294 // Decrement and increment _allocated_used_words
295 static void dec_used(Metaspace::MetadataType type, size_t words);
296 static void inc_used(Metaspace::MetadataType type, size_t words);
298 // Total of space allocated to metadata in all Metaspaces.
299 // This sums the space used in each Metachunk by
300 // iterating over the classloader data graph
301 static size_t used_bytes_slow() {
302 return used_bytes_slow(Metaspace::ClassType) +
303 used_bytes_slow(Metaspace::NonClassType);
304 }
306 // Used by MetaspaceCounters
307 static size_t free_chunks_total_words();
308 static size_t free_chunks_total_bytes();
309 static size_t free_chunks_total_bytes(Metaspace::MetadataType mdtype);
311 static size_t allocated_capacity_words(Metaspace::MetadataType mdtype) {
312 return _allocated_capacity_words[mdtype];
313 }
314 static size_t allocated_capacity_words() {
315 return allocated_capacity_words(Metaspace::NonClassType) +
316 allocated_capacity_words(Metaspace::ClassType);
317 }
318 static size_t allocated_capacity_bytes(Metaspace::MetadataType mdtype) {
319 return allocated_capacity_words(mdtype) * BytesPerWord;
320 }
321 static size_t allocated_capacity_bytes() {
322 return allocated_capacity_words() * BytesPerWord;
323 }
325 static size_t allocated_used_words(Metaspace::MetadataType mdtype) {
326 return _allocated_used_words[mdtype];
327 }
328 static size_t allocated_used_words() {
329 return allocated_used_words(Metaspace::NonClassType) +
330 allocated_used_words(Metaspace::ClassType);
331 }
332 static size_t allocated_used_bytes(Metaspace::MetadataType mdtype) {
333 return allocated_used_words(mdtype) * BytesPerWord;
334 }
335 static size_t allocated_used_bytes() {
336 return allocated_used_words() * BytesPerWord;
337 }
339 static size_t free_bytes();
340 static size_t free_bytes(Metaspace::MetadataType mdtype);
342 static size_t reserved_bytes(Metaspace::MetadataType mdtype);
343 static size_t reserved_bytes() {
344 return reserved_bytes(Metaspace::ClassType) +
345 reserved_bytes(Metaspace::NonClassType);
346 }
348 static size_t committed_bytes(Metaspace::MetadataType mdtype);
349 static size_t committed_bytes() {
350 return committed_bytes(Metaspace::ClassType) +
351 committed_bytes(Metaspace::NonClassType);
352 }
354 static size_t min_chunk_size_words();
355 static size_t min_chunk_size_bytes() {
356 return min_chunk_size_words() * BytesPerWord;
357 }
359 static bool has_chunk_free_list(Metaspace::MetadataType mdtype);
360 static MetaspaceChunkFreeListSummary chunk_free_list_summary(Metaspace::MetadataType mdtype);
362 // Print change in used metadata.
363 static void print_metaspace_change(size_t prev_metadata_used);
364 static void print_on(outputStream * out);
365 static void print_on(outputStream * out, Metaspace::MetadataType mdtype);
367 static void print_class_waste(outputStream* out);
368 static void print_waste(outputStream* out);
369 static void dump(outputStream* out);
370 static void verify_free_chunks();
371 // Checks that the values returned by allocated_capacity_bytes() and
372 // capacity_bytes_slow() are the same.
373 static void verify_capacity();
374 static void verify_used();
375 static void verify_metrics();
376 };
378 // Metaspace are deallocated when their class loader are GC'ed.
379 // This class implements a policy for inducing GC's to recover
380 // Metaspaces.
382 class MetaspaceGC : AllStatic {
384 // The current high-water-mark for inducing a GC.
385 // When committed memory of all metaspaces reaches this value,
386 // a GC is induced and the value is increased. Size is in bytes.
387 static volatile intptr_t _capacity_until_GC;
389 // For a CMS collection, signal that a concurrent collection should
390 // be started.
391 static bool _should_concurrent_collect;
393 static uint _shrink_factor;
395 static size_t shrink_factor() { return _shrink_factor; }
396 void set_shrink_factor(uint v) { _shrink_factor = v; }
398 public:
400 static void initialize() { _capacity_until_GC = MetaspaceSize; }
402 static size_t capacity_until_GC();
403 static size_t inc_capacity_until_GC(size_t v);
404 static size_t dec_capacity_until_GC(size_t v);
406 static bool should_concurrent_collect() { return _should_concurrent_collect; }
407 static void set_should_concurrent_collect(bool v) {
408 _should_concurrent_collect = v;
409 }
411 // The amount to increase the high-water-mark (_capacity_until_GC)
412 static size_t delta_capacity_until_GC(size_t bytes);
414 // Tells if we have can expand metaspace without hitting set limits.
415 static bool can_expand(size_t words, bool is_class);
417 // Returns amount that we can expand without hitting a GC,
418 // measured in words.
419 static size_t allowed_expansion();
421 // Calculate the new high-water mark at which to induce
422 // a GC.
423 static void compute_new_size();
424 };
426 #endif // SHARE_VM_MEMORY_METASPACE_HPP