src/share/vm/utilities/stack.inline.hpp

Tue, 28 Sep 2010 15:56:15 -0700

author
jcoomes
date
Tue, 28 Sep 2010 15:56:15 -0700
changeset 2191
894b1d7c7e01
child 2314
f95d63e2154a
permissions
-rw-r--r--

6423256: GC stacks should use a better data structure
6942771: SEGV in ParScanThreadState::take_from_overflow_stack
Reviewed-by: apetrusenko, ysr, pbk

jcoomes@2191 1 /*
jcoomes@2191 2 * Copyright 2009 Sun Microsystems, Inc. All Rights Reserved.
jcoomes@2191 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
jcoomes@2191 4 *
jcoomes@2191 5 * This code is free software; you can redistribute it and/or modify it
jcoomes@2191 6 * under the terms of the GNU General Public License version 2 only, as
jcoomes@2191 7 * published by the Free Software Foundation.
jcoomes@2191 8 *
jcoomes@2191 9 * This code is distributed in the hope that it will be useful, but WITHOUT
jcoomes@2191 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
jcoomes@2191 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
jcoomes@2191 12 * version 2 for more details (a copy is included in the LICENSE file that
jcoomes@2191 13 * accompanied this code).
jcoomes@2191 14 *
jcoomes@2191 15 * You should have received a copy of the GNU General Public License version
jcoomes@2191 16 * 2 along with this work; if not, write to the Free Software Foundation,
jcoomes@2191 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
jcoomes@2191 18 *
jcoomes@2191 19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
jcoomes@2191 20 * CA 95054 USA or visit www.sun.com if you need additional information or
jcoomes@2191 21 * have any questions.
jcoomes@2191 22 *
jcoomes@2191 23 */
jcoomes@2191 24
jcoomes@2191 25 StackBase::StackBase(size_t segment_size, size_t max_cache_size,
jcoomes@2191 26 size_t max_size):
jcoomes@2191 27 _seg_size(segment_size),
jcoomes@2191 28 _max_cache_size(max_cache_size),
jcoomes@2191 29 _max_size(adjust_max_size(max_size, segment_size))
jcoomes@2191 30 {
jcoomes@2191 31 assert(_max_size % _seg_size == 0, "not a multiple");
jcoomes@2191 32 }
jcoomes@2191 33
jcoomes@2191 34 size_t StackBase::adjust_max_size(size_t max_size, size_t seg_size)
jcoomes@2191 35 {
jcoomes@2191 36 assert(seg_size > 0, "cannot be 0");
jcoomes@2191 37 assert(max_size >= seg_size || max_size == 0, "max_size too small");
jcoomes@2191 38 const size_t limit = max_uintx - (seg_size - 1);
jcoomes@2191 39 if (max_size == 0 || max_size > limit) {
jcoomes@2191 40 max_size = limit;
jcoomes@2191 41 }
jcoomes@2191 42 return (max_size + seg_size - 1) / seg_size * seg_size;
jcoomes@2191 43 }
jcoomes@2191 44
jcoomes@2191 45 template <class E>
jcoomes@2191 46 Stack<E>::Stack(size_t segment_size, size_t max_cache_size, size_t max_size):
jcoomes@2191 47 StackBase(adjust_segment_size(segment_size), max_cache_size, max_size)
jcoomes@2191 48 {
jcoomes@2191 49 reset(true);
jcoomes@2191 50 }
jcoomes@2191 51
jcoomes@2191 52 template <class E>
jcoomes@2191 53 void Stack<E>::push(E item)
jcoomes@2191 54 {
jcoomes@2191 55 assert(!is_full(), "pushing onto a full stack");
jcoomes@2191 56 if (_cur_seg_size == _seg_size) {
jcoomes@2191 57 push_segment();
jcoomes@2191 58 }
jcoomes@2191 59 _cur_seg[_cur_seg_size] = item;
jcoomes@2191 60 ++_cur_seg_size;
jcoomes@2191 61 }
jcoomes@2191 62
jcoomes@2191 63 template <class E>
jcoomes@2191 64 E Stack<E>::pop()
jcoomes@2191 65 {
jcoomes@2191 66 assert(!is_empty(), "popping from an empty stack");
jcoomes@2191 67 if (_cur_seg_size == 1) {
jcoomes@2191 68 E tmp = _cur_seg[--_cur_seg_size];
jcoomes@2191 69 pop_segment();
jcoomes@2191 70 return tmp;
jcoomes@2191 71 }
jcoomes@2191 72 return _cur_seg[--_cur_seg_size];
jcoomes@2191 73 }
jcoomes@2191 74
jcoomes@2191 75 template <class E>
jcoomes@2191 76 void Stack<E>::clear(bool clear_cache)
jcoomes@2191 77 {
jcoomes@2191 78 free_segments(_cur_seg);
jcoomes@2191 79 if (clear_cache) free_segments(_cache);
jcoomes@2191 80 reset(clear_cache);
jcoomes@2191 81 }
jcoomes@2191 82
jcoomes@2191 83 template <class E>
jcoomes@2191 84 size_t Stack<E>::default_segment_size()
jcoomes@2191 85 {
jcoomes@2191 86 // Number of elements that fit in 4K bytes minus the size of two pointers
jcoomes@2191 87 // (link field and malloc header).
jcoomes@2191 88 return (4096 - 2 * sizeof(E*)) / sizeof(E);
jcoomes@2191 89 }
jcoomes@2191 90
jcoomes@2191 91 template <class E>
jcoomes@2191 92 size_t Stack<E>::adjust_segment_size(size_t seg_size)
jcoomes@2191 93 {
jcoomes@2191 94 const size_t elem_sz = sizeof(E);
jcoomes@2191 95 const size_t ptr_sz = sizeof(E*);
jcoomes@2191 96 assert(elem_sz % ptr_sz == 0 || ptr_sz % elem_sz == 0, "bad element size");
jcoomes@2191 97 if (elem_sz < ptr_sz) {
jcoomes@2191 98 return align_size_up(seg_size * elem_sz, ptr_sz) / elem_sz;
jcoomes@2191 99 }
jcoomes@2191 100 return seg_size;
jcoomes@2191 101 }
jcoomes@2191 102
jcoomes@2191 103 template <class E>
jcoomes@2191 104 size_t Stack<E>::link_offset() const
jcoomes@2191 105 {
jcoomes@2191 106 return align_size_up(_seg_size * sizeof(E), sizeof(E*));
jcoomes@2191 107 }
jcoomes@2191 108
jcoomes@2191 109 template <class E>
jcoomes@2191 110 size_t Stack<E>::segment_bytes() const
jcoomes@2191 111 {
jcoomes@2191 112 return link_offset() + sizeof(E*);
jcoomes@2191 113 }
jcoomes@2191 114
jcoomes@2191 115 template <class E>
jcoomes@2191 116 E** Stack<E>::link_addr(E* seg) const
jcoomes@2191 117 {
jcoomes@2191 118 return (E**) ((char*)seg + link_offset());
jcoomes@2191 119 }
jcoomes@2191 120
jcoomes@2191 121 template <class E>
jcoomes@2191 122 E* Stack<E>::get_link(E* seg) const
jcoomes@2191 123 {
jcoomes@2191 124 return *link_addr(seg);
jcoomes@2191 125 }
jcoomes@2191 126
jcoomes@2191 127 template <class E>
jcoomes@2191 128 E* Stack<E>::set_link(E* new_seg, E* old_seg)
jcoomes@2191 129 {
jcoomes@2191 130 *link_addr(new_seg) = old_seg;
jcoomes@2191 131 return new_seg;
jcoomes@2191 132 }
jcoomes@2191 133
jcoomes@2191 134 template <class E>
jcoomes@2191 135 E* Stack<E>::alloc(size_t bytes)
jcoomes@2191 136 {
jcoomes@2191 137 return (E*) NEW_C_HEAP_ARRAY(char, bytes);
jcoomes@2191 138 }
jcoomes@2191 139
jcoomes@2191 140 template <class E>
jcoomes@2191 141 void Stack<E>::free(E* addr, size_t bytes)
jcoomes@2191 142 {
jcoomes@2191 143 FREE_C_HEAP_ARRAY(char, (char*) addr);
jcoomes@2191 144 }
jcoomes@2191 145
jcoomes@2191 146 template <class E>
jcoomes@2191 147 void Stack<E>::push_segment()
jcoomes@2191 148 {
jcoomes@2191 149 assert(_cur_seg_size == _seg_size, "current segment is not full");
jcoomes@2191 150 E* next;
jcoomes@2191 151 if (_cache_size > 0) {
jcoomes@2191 152 // Use a cached segment.
jcoomes@2191 153 next = _cache;
jcoomes@2191 154 _cache = get_link(_cache);
jcoomes@2191 155 --_cache_size;
jcoomes@2191 156 } else {
jcoomes@2191 157 next = alloc(segment_bytes());
jcoomes@2191 158 DEBUG_ONLY(zap_segment(next, true);)
jcoomes@2191 159 }
jcoomes@2191 160 const bool at_empty_transition = is_empty();
jcoomes@2191 161 _cur_seg = set_link(next, _cur_seg);
jcoomes@2191 162 _cur_seg_size = 0;
jcoomes@2191 163 _full_seg_size += at_empty_transition ? 0 : _seg_size;
jcoomes@2191 164 DEBUG_ONLY(verify(at_empty_transition);)
jcoomes@2191 165 }
jcoomes@2191 166
jcoomes@2191 167 template <class E>
jcoomes@2191 168 void Stack<E>::pop_segment()
jcoomes@2191 169 {
jcoomes@2191 170 assert(_cur_seg_size == 0, "current segment is not empty");
jcoomes@2191 171 E* const prev = get_link(_cur_seg);
jcoomes@2191 172 if (_cache_size < _max_cache_size) {
jcoomes@2191 173 // Add the current segment to the cache.
jcoomes@2191 174 DEBUG_ONLY(zap_segment(_cur_seg, false);)
jcoomes@2191 175 _cache = set_link(_cur_seg, _cache);
jcoomes@2191 176 ++_cache_size;
jcoomes@2191 177 } else {
jcoomes@2191 178 DEBUG_ONLY(zap_segment(_cur_seg, true);)
jcoomes@2191 179 free(_cur_seg, segment_bytes());
jcoomes@2191 180 }
jcoomes@2191 181 const bool at_empty_transition = prev == NULL;
jcoomes@2191 182 _cur_seg = prev;
jcoomes@2191 183 _cur_seg_size = _seg_size;
jcoomes@2191 184 _full_seg_size -= at_empty_transition ? 0 : _seg_size;
jcoomes@2191 185 DEBUG_ONLY(verify(at_empty_transition);)
jcoomes@2191 186 }
jcoomes@2191 187
jcoomes@2191 188 template <class E>
jcoomes@2191 189 void Stack<E>::free_segments(E* seg)
jcoomes@2191 190 {
jcoomes@2191 191 const size_t bytes = segment_bytes();
jcoomes@2191 192 while (seg != NULL) {
jcoomes@2191 193 E* const prev = get_link(seg);
jcoomes@2191 194 free(seg, bytes);
jcoomes@2191 195 seg = prev;
jcoomes@2191 196 }
jcoomes@2191 197 }
jcoomes@2191 198
jcoomes@2191 199 template <class E>
jcoomes@2191 200 void Stack<E>::reset(bool reset_cache)
jcoomes@2191 201 {
jcoomes@2191 202 _cur_seg_size = _seg_size; // So push() will alloc a new segment.
jcoomes@2191 203 _full_seg_size = 0;
jcoomes@2191 204 _cur_seg = NULL;
jcoomes@2191 205 if (reset_cache) {
jcoomes@2191 206 _cache_size = 0;
jcoomes@2191 207 _cache = NULL;
jcoomes@2191 208 }
jcoomes@2191 209 }
jcoomes@2191 210
jcoomes@2191 211 #ifdef ASSERT
jcoomes@2191 212 template <class E>
jcoomes@2191 213 void Stack<E>::verify(bool at_empty_transition) const
jcoomes@2191 214 {
jcoomes@2191 215 assert(size() <= max_size(), "stack exceeded bounds");
jcoomes@2191 216 assert(cache_size() <= max_cache_size(), "cache exceeded bounds");
jcoomes@2191 217 assert(_cur_seg_size <= segment_size(), "segment index exceeded bounds");
jcoomes@2191 218
jcoomes@2191 219 assert(_full_seg_size % _seg_size == 0, "not a multiple");
jcoomes@2191 220 assert(at_empty_transition || is_empty() == (size() == 0), "mismatch");
jcoomes@2191 221 assert((_cache == NULL) == (cache_size() == 0), "mismatch");
jcoomes@2191 222
jcoomes@2191 223 if (is_empty()) {
jcoomes@2191 224 assert(_cur_seg_size == segment_size(), "sanity");
jcoomes@2191 225 }
jcoomes@2191 226 }
jcoomes@2191 227
jcoomes@2191 228 template <class E>
jcoomes@2191 229 void Stack<E>::zap_segment(E* seg, bool zap_link_field) const
jcoomes@2191 230 {
jcoomes@2191 231 if (!ZapStackSegments) return;
jcoomes@2191 232 const size_t zap_bytes = segment_bytes() - (zap_link_field ? 0 : sizeof(E*));
jcoomes@2191 233 uint32_t* cur = (uint32_t*)seg;
jcoomes@2191 234 const uint32_t* end = cur + zap_bytes / sizeof(uint32_t);
jcoomes@2191 235 while (cur < end) {
jcoomes@2191 236 *cur++ = 0xfadfaded;
jcoomes@2191 237 }
jcoomes@2191 238 }
jcoomes@2191 239 #endif
jcoomes@2191 240
jcoomes@2191 241 template <class E>
jcoomes@2191 242 E* ResourceStack<E>::alloc(size_t bytes)
jcoomes@2191 243 {
jcoomes@2191 244 return (E*) resource_allocate_bytes(bytes);
jcoomes@2191 245 }
jcoomes@2191 246
jcoomes@2191 247 template <class E>
jcoomes@2191 248 void ResourceStack<E>::free(E* addr, size_t bytes)
jcoomes@2191 249 {
jcoomes@2191 250 resource_free_bytes((char*) addr, bytes);
jcoomes@2191 251 }
jcoomes@2191 252
jcoomes@2191 253 template <class E>
jcoomes@2191 254 void StackIterator<E>::sync()
jcoomes@2191 255 {
jcoomes@2191 256 _full_seg_size = _stack._full_seg_size;
jcoomes@2191 257 _cur_seg_size = _stack._cur_seg_size;
jcoomes@2191 258 _cur_seg = _stack._cur_seg;
jcoomes@2191 259 }
jcoomes@2191 260
jcoomes@2191 261 template <class E>
jcoomes@2191 262 E* StackIterator<E>::next_addr()
jcoomes@2191 263 {
jcoomes@2191 264 assert(!is_empty(), "no items left");
jcoomes@2191 265 if (_cur_seg_size == 1) {
jcoomes@2191 266 E* addr = _cur_seg;
jcoomes@2191 267 _cur_seg = _stack.get_link(_cur_seg);
jcoomes@2191 268 _cur_seg_size = _stack.segment_size();
jcoomes@2191 269 _full_seg_size -= _stack.segment_size();
jcoomes@2191 270 return addr;
jcoomes@2191 271 }
jcoomes@2191 272 return _cur_seg + --_cur_seg_size;
jcoomes@2191 273 }

mercurial