Sat, 01 Sep 2012 13:25:18 -0400
6964458: Reimplement class meta-data storage to use native memory
Summary: Remove PermGen, allocate meta-data in metaspace linked to class loaders, rewrite GC walking, rewrite and rename metadata to be C++ classes
Reviewed-by: jmasa, stefank, never, coleenp, kvn, brutisso, mgerdin, dholmes, jrose, twisti, roland
Contributed-by: jmasa <jon.masamitsu@oracle.com>, stefank <stefan.karlsson@oracle.com>, mgerdin <mikael.gerdin@oracle.com>, never <tom.rodriguez@oracle.com>
1 /*
2 * Copyright (c) 1997, 2012, 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 */
25 #ifndef SHARE_VM_UTILITIES_GROWABLEARRAY_HPP
26 #define SHARE_VM_UTILITIES_GROWABLEARRAY_HPP
28 #include "memory/allocation.hpp"
29 #include "memory/allocation.inline.hpp"
30 #include "utilities/debug.hpp"
31 #include "utilities/globalDefinitions.hpp"
32 #include "utilities/top.hpp"
34 // A growable array.
36 /*************************************************************************/
37 /* */
38 /* WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING */
39 /* */
40 /* Should you use GrowableArrays to contain handles you must be certain */
41 /* the the GrowableArray does not outlive the HandleMark that contains */
42 /* the handles. Since GrowableArrays are typically resource allocated */
43 /* the following is an example of INCORRECT CODE, */
44 /* */
45 /* ResourceMark rm; */
46 /* GrowableArray<Handle>* arr = new GrowableArray<Handle>(size); */
47 /* if (blah) { */
48 /* while (...) { */
49 /* HandleMark hm; */
50 /* ... */
51 /* Handle h(THREAD, some_oop); */
52 /* arr->append(h); */
53 /* } */
54 /* } */
55 /* if (arr->length() != 0 ) { */
56 /* oop bad_oop = arr->at(0)(); // Handle is BAD HERE. */
57 /* ... */
58 /* } */
59 /* */
60 /* If the GrowableArrays you are creating is C_Heap allocated then it */
61 /* hould not old handles since the handles could trivially try and */
62 /* outlive their HandleMark. In some situations you might need to do */
63 /* this and it would be legal but be very careful and see if you can do */
64 /* the code in some other manner. */
65 /* */
66 /*************************************************************************/
68 // To call default constructor the placement operator new() is used.
69 // It should be empty (it only returns the passed void* pointer).
70 // The definition of placement operator new(size_t, void*) in the <new>.
72 #include <new>
74 // Need the correct linkage to call qsort without warnings
75 extern "C" {
76 typedef int (*_sort_Fn)(const void *, const void *);
77 }
79 class GenericGrowableArray : public ResourceObj {
80 friend class VMStructs;
82 protected:
83 int _len; // current length
84 int _max; // maximum length
85 Arena* _arena; // Indicates where allocation occurs:
86 // 0 means default ResourceArea
87 // 1 means on C heap
88 // otherwise, allocate in _arena
90 MEMFLAGS _memflags; // memory type if allocation in C heap
92 #ifdef ASSERT
93 int _nesting; // resource area nesting at creation
94 void set_nesting();
95 void check_nesting();
96 #else
97 #define set_nesting();
98 #define check_nesting();
99 #endif
101 // Where are we going to allocate memory?
102 bool on_C_heap() { return _arena == (Arena*)1; }
103 bool on_stack () { return _arena == NULL; }
104 bool on_arena () { return _arena > (Arena*)1; }
106 // This GA will use the resource stack for storage if c_heap==false,
107 // Else it will use the C heap. Use clear_and_deallocate to avoid leaks.
108 GenericGrowableArray(int initial_size, int initial_len, bool c_heap, MEMFLAGS flags = mtNone) {
109 _len = initial_len;
110 _max = initial_size;
111 _memflags = flags;
113 // memory type has to be specified for C heap allocation
114 assert(!(c_heap && flags == mtNone), "memory type not specified for C heap object");
116 assert(_len >= 0 && _len <= _max, "initial_len too big");
117 _arena = (c_heap ? (Arena*)1 : NULL);
118 set_nesting();
119 assert(!on_C_heap() || allocated_on_C_heap(), "growable array must be on C heap if elements are");
120 assert(!on_stack() ||
121 (allocated_on_res_area() || allocated_on_stack()),
122 "growable array must be on stack if elements are not on arena and not on C heap");
123 }
125 // This GA will use the given arena for storage.
126 // Consider using new(arena) GrowableArray<T> to allocate the header.
127 GenericGrowableArray(Arena* arena, int initial_size, int initial_len) {
128 _len = initial_len;
129 _max = initial_size;
130 assert(_len >= 0 && _len <= _max, "initial_len too big");
131 _arena = arena;
132 _memflags = mtNone;
134 assert(on_arena(), "arena has taken on reserved value 0 or 1");
135 // Relax next assert to allow object allocation on resource area,
136 // on stack or embedded into an other object.
137 assert(allocated_on_arena() || allocated_on_stack(),
138 "growable array must be on arena or on stack if elements are on arena");
139 }
141 void* raw_allocate(int elementSize);
143 // some uses pass the Thread explicitly for speed (4990299 tuning)
144 void* raw_allocate(Thread* thread, int elementSize) {
145 assert(on_stack(), "fast ResourceObj path only");
146 return (void*)resource_allocate_bytes(thread, elementSize * _max);
147 }
148 };
150 template<class E> class GrowableArray : public GenericGrowableArray {
151 friend class VMStructs;
153 private:
154 E* _data; // data array
156 void grow(int j);
157 void raw_at_put_grow(int i, const E& p, const E& fill);
158 void clear_and_deallocate();
159 public:
160 GrowableArray(Thread* thread, int initial_size) : GenericGrowableArray(initial_size, 0, false) {
161 _data = (E*)raw_allocate(thread, sizeof(E));
162 for (int i = 0; i < _max; i++) ::new ((void*)&_data[i]) E();
163 }
165 GrowableArray(int initial_size, bool C_heap = false, MEMFLAGS F = mtInternal)
166 : GenericGrowableArray(initial_size, 0, C_heap, F) {
167 _data = (E*)raw_allocate(sizeof(E));
168 for (int i = 0; i < _max; i++) ::new ((void*)&_data[i]) E();
169 }
171 GrowableArray(int initial_size, int initial_len, const E& filler, bool C_heap = false, MEMFLAGS memflags = mtInternal)
172 : GenericGrowableArray(initial_size, initial_len, C_heap, memflags) {
173 _data = (E*)raw_allocate(sizeof(E));
174 int i = 0;
175 for (; i < _len; i++) ::new ((void*)&_data[i]) E(filler);
176 for (; i < _max; i++) ::new ((void*)&_data[i]) E();
177 }
179 GrowableArray(Arena* arena, int initial_size, int initial_len, const E& filler) : GenericGrowableArray(arena, initial_size, initial_len) {
180 _data = (E*)raw_allocate(sizeof(E));
181 int i = 0;
182 for (; i < _len; i++) ::new ((void*)&_data[i]) E(filler);
183 for (; i < _max; i++) ::new ((void*)&_data[i]) E();
184 }
186 GrowableArray() : GenericGrowableArray(2, 0, false) {
187 _data = (E*)raw_allocate(sizeof(E));
188 ::new ((void*)&_data[0]) E();
189 ::new ((void*)&_data[1]) E();
190 }
192 // Does nothing for resource and arena objects
193 ~GrowableArray() { if (on_C_heap()) clear_and_deallocate(); }
195 void clear() { _len = 0; }
196 int length() const { return _len; }
197 void trunc_to(int l) { assert(l <= _len,"cannot increase length"); _len = l; }
198 bool is_empty() const { return _len == 0; }
199 bool is_nonempty() const { return _len != 0; }
200 bool is_full() const { return _len == _max; }
201 DEBUG_ONLY(E* data_addr() const { return _data; })
203 void print();
205 int append(const E& elem) {
206 check_nesting();
207 if (_len == _max) grow(_len);
208 int idx = _len++;
209 _data[idx] = elem;
210 return idx;
211 }
213 bool append_if_missing(const E& elem) {
214 // Returns TRUE if elem is added.
215 bool missed = !contains(elem);
216 if (missed) append(elem);
217 return missed;
218 }
220 E at(int i) const {
221 assert(0 <= i && i < _len, "illegal index");
222 return _data[i];
223 }
225 E* adr_at(int i) const {
226 assert(0 <= i && i < _len, "illegal index");
227 return &_data[i];
228 }
230 E first() const {
231 assert(_len > 0, "empty list");
232 return _data[0];
233 }
235 E top() const {
236 assert(_len > 0, "empty list");
237 return _data[_len-1];
238 }
240 void push(const E& elem) { append(elem); }
242 E pop() {
243 assert(_len > 0, "empty list");
244 return _data[--_len];
245 }
247 void at_put(int i, const E& elem) {
248 assert(0 <= i && i < _len, "illegal index");
249 _data[i] = elem;
250 }
252 E at_grow(int i, const E& fill = E()) {
253 assert(0 <= i, "negative index");
254 check_nesting();
255 if (i >= _len) {
256 if (i >= _max) grow(i);
257 for (int j = _len; j <= i; j++)
258 _data[j] = fill;
259 _len = i+1;
260 }
261 return _data[i];
262 }
264 void at_put_grow(int i, const E& elem, const E& fill = E()) {
265 assert(0 <= i, "negative index");
266 check_nesting();
267 raw_at_put_grow(i, elem, fill);
268 }
270 bool contains(const E& elem) const {
271 for (int i = 0; i < _len; i++) {
272 if (_data[i] == elem) return true;
273 }
274 return false;
275 }
277 int find(const E& elem) const {
278 for (int i = 0; i < _len; i++) {
279 if (_data[i] == elem) return i;
280 }
281 return -1;
282 }
284 int find_from_end(const E& elem) const {
285 for (int i = _len-1; i >= 0; i--) {
286 if (_data[i] == elem) return i;
287 }
288 return -1;
289 }
291 int find(void* token, bool f(void*, E)) const {
292 for (int i = 0; i < _len; i++) {
293 if (f(token, _data[i])) return i;
294 }
295 return -1;
296 }
298 int find_from_end(void* token, bool f(void*, E)) const {
299 // start at the end of the array
300 for (int i = _len-1; i >= 0; i--) {
301 if (f(token, _data[i])) return i;
302 }
303 return -1;
304 }
306 void remove(const E& elem) {
307 for (int i = 0; i < _len; i++) {
308 if (_data[i] == elem) {
309 for (int j = i + 1; j < _len; j++) _data[j-1] = _data[j];
310 _len--;
311 return;
312 }
313 }
314 ShouldNotReachHere();
315 }
317 // The order is preserved.
318 void remove_at(int index) {
319 assert(0 <= index && index < _len, "illegal index");
320 for (int j = index + 1; j < _len; j++) _data[j-1] = _data[j];
321 _len--;
322 }
324 // The order is changed.
325 void delete_at(int index) {
326 assert(0 <= index && index < _len, "illegal index");
327 if (index < --_len) {
328 // Replace removed element with last one.
329 _data[index] = _data[_len];
330 }
331 }
333 // inserts the given element before the element at index i
334 void insert_before(const int idx, const E& elem) {
335 check_nesting();
336 if (_len == _max) grow(_len);
337 for (int j = _len - 1; j >= idx; j--) {
338 _data[j + 1] = _data[j];
339 }
340 _len++;
341 _data[idx] = elem;
342 }
344 void appendAll(const GrowableArray<E>* l) {
345 for (int i = 0; i < l->_len; i++) {
346 raw_at_put_grow(_len, l->_data[i], 0);
347 }
348 }
350 void sort(int f(E*,E*)) {
351 qsort(_data, length(), sizeof(E), (_sort_Fn)f);
352 }
353 // sort by fixed-stride sub arrays:
354 void sort(int f(E*,E*), int stride) {
355 qsort(_data, length() / stride, sizeof(E) * stride, (_sort_Fn)f);
356 }
357 };
359 // Global GrowableArray methods (one instance in the library per each 'E' type).
361 template<class E> void GrowableArray<E>::grow(int j) {
362 // grow the array by doubling its size (amortized growth)
363 int old_max = _max;
364 if (_max == 0) _max = 1; // prevent endless loop
365 while (j >= _max) _max = _max*2;
366 // j < _max
367 E* newData = (E*)raw_allocate(sizeof(E));
368 int i = 0;
369 for ( ; i < _len; i++) ::new ((void*)&newData[i]) E(_data[i]);
370 for ( ; i < _max; i++) ::new ((void*)&newData[i]) E();
371 for (i = 0; i < old_max; i++) _data[i].~E();
372 if (on_C_heap() && _data != NULL) {
373 FreeHeap(_data);
374 }
375 _data = newData;
376 }
378 template<class E> void GrowableArray<E>::raw_at_put_grow(int i, const E& p, const E& fill) {
379 if (i >= _len) {
380 if (i >= _max) grow(i);
381 for (int j = _len; j < i; j++)
382 _data[j] = fill;
383 _len = i+1;
384 }
385 _data[i] = p;
386 }
388 // This function clears and deallocate the data in the growable array that
389 // has been allocated on the C heap. It's not public - called by the
390 // destructor.
391 template<class E> void GrowableArray<E>::clear_and_deallocate() {
392 assert(on_C_heap(),
393 "clear_and_deallocate should only be called when on C heap");
394 clear();
395 if (_data != NULL) {
396 for (int i = 0; i < _max; i++) _data[i].~E();
397 FreeHeap(_data);
398 _data = NULL;
399 }
400 }
402 template<class E> void GrowableArray<E>::print() {
403 tty->print("Growable Array " INTPTR_FORMAT, this);
404 tty->print(": length %ld (_max %ld) { ", _len, _max);
405 for (int i = 0; i < _len; i++) tty->print(INTPTR_FORMAT " ", *(intptr_t*)&(_data[i]));
406 tty->print("}\n");
407 }
409 #endif // SHARE_VM_UTILITIES_GROWABLEARRAY_HPP