1 /* 2 * Copyright (c) 1997, 2019, 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. 22 * 23 */ 24 25 #include "precompiled.hpp" 26 #include "memory/heap.hpp" 27 #include "oops/oop.inline.hpp" 28 #include "runtime/os.hpp" 29 #include "services/memTracker.hpp" 30 #include "utilities/align.hpp" 31 32 size_t CodeHeap::header_size() { 33 return sizeof(HeapBlock); 34 } 35 36 37 // Implementation of Heap 38 39 CodeHeap::CodeHeap(const char* name, const int code_blob_type) 40 : _code_blob_type(code_blob_type) { 41 _name = name; 42 _number_of_committed_segments = 0; 43 _number_of_reserved_segments = 0; 44 _segment_size = 0; 45 _log2_segment_size = 0; 46 _next_segment = 0; 47 _freelist = NULL; 48 _freelist_segments = 0; 49 _freelist_length = 0; 50 _max_allocated_capacity = 0; 51 _blob_count = 0; 52 _nmethod_count = 0; 53 _adapter_count = 0; 54 _full_count = 0; 55 } 56 57 58 // The segmap is marked free for that part of the heap 59 // which has not been allocated yet (beyond _next_segment). 60 // "Allocated" space in this context means there exists a 61 // HeapBlock or a FreeBlock describing this space. 62 // This method takes segment map indices as range boundaries 63 void CodeHeap::mark_segmap_as_free(size_t beg, size_t end) { 64 assert( beg < _number_of_committed_segments, "interval begin out of bounds"); 65 assert(beg < end && end <= _number_of_committed_segments, "interval end out of bounds"); 66 // Don't do unpredictable things in PRODUCT build 67 if (beg < end) { 68 // setup _segmap pointers for faster indexing 69 address p = (address)_segmap.low() + beg; 70 address q = (address)_segmap.low() + end; 71 // initialize interval 72 memset(p, free_sentinel, q-p); 73 } 74 } 75 76 // Don't get confused here. 77 // All existing blocks, no matter if they are used() or free(), 78 // have their segmap marked as used. This allows to find the 79 // block header (HeapBlock or FreeBlock) for any pointer 80 // within the allocated range (upper limit: _next_segment). 81 // This method takes segment map indices as range boundaries 82 void CodeHeap::mark_segmap_as_used(size_t beg, size_t end) { 83 assert( beg < _number_of_committed_segments, "interval begin out of bounds"); 84 assert(beg < end && end <= _number_of_committed_segments, "interval end out of bounds"); 85 // Don't do unpredictable things in PRODUCT build 86 if (beg < end) { 87 // setup _segmap pointers for faster indexing 88 address p = (address)_segmap.low() + beg; 89 address q = (address)_segmap.low() + end; 90 // initialize interval 91 int i = 0; 92 while (p < q) { 93 *p++ = i++; 94 if (i == free_sentinel) i = 1; 95 } 96 } 97 } 98 99 void CodeHeap::invalidate(size_t beg, size_t end, size_t hdr_size) { 100 #ifndef PRODUCT 101 // Fill the given range with some bad value. 102 // length is expected to be in segment_size units. 103 // This prevents inadvertent execution of code leftover from previous use. 104 char* p = low_boundary() + segments_to_size(beg) + hdr_size; 105 memset(p, badCodeHeapNewVal, segments_to_size(end-beg)-hdr_size); 106 #endif 107 } 108 109 void CodeHeap::clear(size_t beg, size_t end) { 110 mark_segmap_as_free(beg, end); 111 invalidate(beg, end, 0); 112 } 113 114 void CodeHeap::clear() { 115 _next_segment = 0; 116 clear(_next_segment, _number_of_committed_segments); 117 } 118 119 120 static size_t align_to_page_size(size_t size) { 121 const size_t alignment = (size_t)os::vm_page_size(); 122 assert(is_power_of_2(alignment), "no kidding ???"); 123 return (size + alignment - 1) & ~(alignment - 1); 124 } 125 126 127 void CodeHeap::on_code_mapping(char* base, size_t size) { 128 #ifdef LINUX 129 extern void linux_wrap_code(char* base, size_t size); 130 linux_wrap_code(base, size); 131 #endif 132 } 133 134 135 bool CodeHeap::reserve(ReservedSpace rs, size_t committed_size, size_t segment_size) { 136 assert(rs.size() >= committed_size, "reserved < committed"); 137 assert(segment_size >= sizeof(FreeBlock), "segment size is too small"); 138 assert(is_power_of_2(segment_size), "segment_size must be a power of 2"); 139 140 _segment_size = segment_size; 141 _log2_segment_size = exact_log2(segment_size); 142 143 // Reserve and initialize space for _memory. 144 size_t page_size = os::vm_page_size(); 145 if (os::can_execute_large_page_memory()) { 146 const size_t min_pages = 8; 147 page_size = MIN2(os::page_size_for_region_aligned(committed_size, min_pages), 148 os::page_size_for_region_aligned(rs.size(), min_pages)); 149 } 150 151 const size_t granularity = os::vm_allocation_granularity(); 152 const size_t c_size = align_up(committed_size, page_size); 153 154 os::trace_page_sizes(_name, committed_size, rs.size(), page_size, 155 rs.base(), rs.size()); 156 if (!_memory.initialize(rs, c_size)) { 157 return false; 158 } 159 160 on_code_mapping(_memory.low(), _memory.committed_size()); 161 _number_of_committed_segments = size_to_segments(_memory.committed_size()); 162 _number_of_reserved_segments = size_to_segments(_memory.reserved_size()); 163 assert(_number_of_reserved_segments >= _number_of_committed_segments, "just checking"); 164 const size_t reserved_segments_alignment = MAX2((size_t)os::vm_page_size(), granularity); 165 const size_t reserved_segments_size = align_up(_number_of_reserved_segments, reserved_segments_alignment); 166 const size_t committed_segments_size = align_to_page_size(_number_of_committed_segments); 167 168 // reserve space for _segmap 169 if (!_segmap.initialize(reserved_segments_size, committed_segments_size)) { 170 return false; 171 } 172 173 MemTracker::record_virtual_memory_type((address)_segmap.low_boundary(), mtCode); 174 175 assert(_segmap.committed_size() >= (size_t) _number_of_committed_segments, "could not commit enough space for segment map"); 176 assert(_segmap.reserved_size() >= (size_t) _number_of_reserved_segments , "could not reserve enough space for segment map"); 177 assert(_segmap.reserved_size() >= _segmap.committed_size() , "just checking"); 178 179 // initialize remaining instance variables, heap memory and segmap 180 clear(); 181 return true; 182 } 183 184 185 bool CodeHeap::expand_by(size_t size) { 186 // expand _memory space 187 size_t dm = align_to_page_size(_memory.committed_size() + size) - _memory.committed_size(); 188 if (dm > 0) { 189 // Use at least the available uncommitted space if 'size' is larger 190 if (_memory.uncommitted_size() != 0 && dm > _memory.uncommitted_size()) { 191 dm = _memory.uncommitted_size(); 192 } 193 char* base = _memory.low() + _memory.committed_size(); 194 if (!_memory.expand_by(dm)) return false; 195 on_code_mapping(base, dm); 196 size_t i = _number_of_committed_segments; 197 _number_of_committed_segments = size_to_segments(_memory.committed_size()); 198 assert(_number_of_reserved_segments == size_to_segments(_memory.reserved_size()), "number of reserved segments should not change"); 199 assert(_number_of_reserved_segments >= _number_of_committed_segments, "just checking"); 200 // expand _segmap space 201 size_t ds = align_to_page_size(_number_of_committed_segments) - _segmap.committed_size(); 202 if ((ds > 0) && !_segmap.expand_by(ds)) { 203 return false; 204 } 205 assert(_segmap.committed_size() >= (size_t) _number_of_committed_segments, "just checking"); 206 // initialize additional space (heap memory and segmap) 207 clear(i, _number_of_committed_segments); 208 } 209 return true; 210 } 211 212 213 void* CodeHeap::allocate(size_t instance_size) { 214 size_t number_of_segments = size_to_segments(instance_size + header_size()); 215 assert(segments_to_size(number_of_segments) >= sizeof(FreeBlock), "not enough room for FreeList"); 216 217 // First check if we can satisfy request from freelist 218 NOT_PRODUCT(verify()); 219 HeapBlock* block = search_freelist(number_of_segments); 220 NOT_PRODUCT(verify()); 221 222 if (block != NULL) { 223 assert(!block->free(), "must be marked free"); 224 guarantee((char*) block >= _memory.low_boundary() && (char*) block < _memory.high(), 225 "The newly allocated block " INTPTR_FORMAT " is not within the heap " 226 "starting with " INTPTR_FORMAT " and ending with " INTPTR_FORMAT, 227 p2i(block), p2i(_memory.low_boundary()), p2i(_memory.high())); 228 // Invalidate the additional space that FreeBlock occupies. The rest of the block should already be invalidated. 229 // This is necessary due to a dubious assert in nmethod.cpp(PcDescCache::reset_to()). 230 DEBUG_ONLY(memset((void*)block->allocated_space(), badCodeHeapNewVal, sizeof(FreeBlock) - sizeof(HeapBlock))); 231 _max_allocated_capacity = MAX2(_max_allocated_capacity, allocated_capacity()); 232 _blob_count++; 233 return block->allocated_space(); 234 } 235 236 // Ensure minimum size for allocation to the heap. 237 number_of_segments = MAX2((int)CodeCacheMinBlockLength, (int)number_of_segments); 238 239 if (_next_segment + number_of_segments <= _number_of_committed_segments) { 240 mark_segmap_as_used(_next_segment, _next_segment + number_of_segments); 241 HeapBlock* b = block_at(_next_segment); 242 b->initialize(number_of_segments); 243 _next_segment += number_of_segments; 244 guarantee((char*) b >= _memory.low_boundary() && (char*) block < _memory.high(), 245 "The newly allocated block " INTPTR_FORMAT " is not within the heap " 246 "starting with " INTPTR_FORMAT " and ending with " INTPTR_FORMAT, 247 p2i(b), p2i(_memory.low_boundary()), p2i(_memory.high())); 248 _max_allocated_capacity = MAX2(_max_allocated_capacity, allocated_capacity()); 249 _blob_count++; 250 return b->allocated_space(); 251 } else { 252 return NULL; 253 } 254 } 255 256 // Split the given block into two at the given segment. 257 // This is helpful when a block was allocated too large 258 // to trim off the unused space at the end (interpreter). 259 // It also helps with splitting a large free block during allocation. 260 // Usage state (used or free) must be set by caller since 261 // we don't know if the resulting blocks will be used or free. 262 // split_at is the segment number (relative to segment_for(b)) 263 // where the split happens. The segment with relative 264 // number split_at is the first segment of the split-off block. 265 HeapBlock* CodeHeap::split_block(HeapBlock *b, size_t split_at) { 266 if (b == NULL) return NULL; 267 // After the split, both blocks must have a size of at least CodeCacheMinBlockLength 268 assert((split_at >= CodeCacheMinBlockLength) && (split_at + CodeCacheMinBlockLength <= b->length()), 269 "split position(%d) out of range [0..%d]", (int)split_at, (int)b->length()); 270 size_t split_segment = segment_for(b) + split_at; 271 size_t b_size = b->length(); 272 size_t newb_size = b_size - split_at; 273 274 HeapBlock* newb = block_at(split_segment); 275 newb->set_length(newb_size); 276 mark_segmap_as_used(segment_for(newb), segment_for(newb) + newb_size); 277 b->set_length(split_at); 278 return newb; 279 } 280 281 void CodeHeap::deallocate_tail(void* p, size_t used_size) { 282 assert(p == find_start(p), "illegal deallocation"); 283 // Find start of HeapBlock 284 HeapBlock* b = (((HeapBlock *)p) - 1); 285 assert(b->allocated_space() == p, "sanity check"); 286 287 size_t actual_number_of_segments = b->length(); 288 size_t used_number_of_segments = size_to_segments(used_size + header_size()); 289 size_t unused_number_of_segments = actual_number_of_segments - used_number_of_segments; 290 guarantee(used_number_of_segments <= actual_number_of_segments, "Must be!"); 291 292 HeapBlock* f = split_block(b, used_number_of_segments); 293 add_to_freelist(f); 294 NOT_PRODUCT(verify()); 295 } 296 297 void CodeHeap::deallocate(void* p) { 298 assert(p == find_start(p), "illegal deallocation"); 299 // Find start of HeapBlock 300 HeapBlock* b = (((HeapBlock *)p) - 1); 301 assert(b->allocated_space() == p, "sanity check"); 302 guarantee((char*) b >= _memory.low_boundary() && (char*) b < _memory.high(), 303 "The block to be deallocated " INTPTR_FORMAT " is not within the heap " 304 "starting with " INTPTR_FORMAT " and ending with " INTPTR_FORMAT, 305 p2i(b), p2i(_memory.low_boundary()), p2i(_memory.high())); 306 add_to_freelist(b); 307 NOT_PRODUCT(verify()); 308 } 309 310 /** 311 * Uses segment map to find the the start (header) of a nmethod. This works as follows: 312 * The memory of the code cache is divided into 'segments'. The size of a segment is 313 * determined by -XX:CodeCacheSegmentSize=XX. Allocation in the code cache can only 314 * happen at segment boundaries. A pointer in the code cache can be mapped to a segment 315 * by calling segment_for(addr). Each time memory is requested from the code cache, 316 * the segmap is updated accordingly. See the following example, which illustrates the 317 * state of code cache and the segment map: (seg -> segment, nm ->nmethod) 318 * 319 * code cache segmap 320 * ----------- --------- 321 * seg 1 | nm 1 | -> | 0 | 322 * seg 2 | nm 1 | -> | 1 | 323 * ... | nm 1 | -> | .. | 324 * seg m | nm 2 | -> | 0 | 325 * seg m+1 | nm 2 | -> | 1 | 326 * ... | nm 2 | -> | 2 | 327 * ... | nm 2 | -> | .. | 328 * ... | nm 2 | -> | 0xFE | 329 * seg m+n | nm 2 | -> | 1 | 330 * ... | nm 2 | -> | | 331 * 332 * A value of '0' in the segmap indicates that this segment contains the beginning of 333 * an nmethod. Let's walk through a simple example: If we want to find the start of 334 * an nmethod that falls into seg 2, we read the value of the segmap[2]. The value 335 * is an offset that points to the segment that contains the start of the nmethod. 336 * Another example: If we want to get the start of nm 2, and we happen to get a pointer 337 * that points to seg m+n, we first read seg[n+m], which returns '1'. So we have to 338 * do one more read of the segmap[m+n-1] to finally get the segment header. 339 */ 340 void* CodeHeap::find_start(void* p) const { 341 if (!contains(p)) { 342 return NULL; 343 } 344 size_t seg_idx = segment_for(p); 345 address seg_map = (address)_segmap.low(); 346 if (is_segment_unused(seg_map[seg_idx])) { 347 return NULL; 348 } 349 while (seg_map[seg_idx] > 0) { 350 seg_idx -= (int)seg_map[seg_idx]; 351 } 352 353 HeapBlock* h = block_at(seg_idx); 354 if (h->free()) { 355 return NULL; 356 } 357 return h->allocated_space(); 358 } 359 360 CodeBlob* CodeHeap::find_blob_unsafe(void* start) const { 361 CodeBlob* result = (CodeBlob*)CodeHeap::find_start(start); 362 if (result != NULL && result->blob_contains((address)start)) { 363 return result; 364 } 365 return NULL; 366 } 367 368 size_t CodeHeap::alignment_unit() const { 369 // this will be a power of two 370 return _segment_size; 371 } 372 373 374 size_t CodeHeap::alignment_offset() const { 375 // The lowest address in any allocated block will be 376 // equal to alignment_offset (mod alignment_unit). 377 return sizeof(HeapBlock) & (_segment_size - 1); 378 } 379 380 // Returns the current block if available and used. 381 // If not, it returns the subsequent block (if available), NULL otherwise. 382 // Free blocks are merged, therefore there is at most one free block 383 // between two used ones. As a result, the subsequent block (if available) is 384 // guaranteed to be used. 385 void* CodeHeap::next_used(HeapBlock* b) const { 386 if (b != NULL && b->free()) b = next_block(b); 387 assert(b == NULL || !b->free(), "must be in use or at end of heap"); 388 return (b == NULL) ? NULL : b->allocated_space(); 389 } 390 391 // Returns the first used HeapBlock 392 HeapBlock* CodeHeap::first_block() const { 393 if (_next_segment > 0) 394 return block_at(0); 395 return NULL; 396 } 397 398 HeapBlock* CodeHeap::block_start(void* q) const { 399 HeapBlock* b = (HeapBlock*)find_start(q); 400 if (b == NULL) return NULL; 401 return b - 1; 402 } 403 404 // Returns the next Heap block an offset into one 405 HeapBlock* CodeHeap::next_block(HeapBlock *b) const { 406 if (b == NULL) return NULL; 407 size_t i = segment_for(b) + b->length(); 408 if (i < _next_segment) 409 return block_at(i); 410 return NULL; 411 } 412 413 414 // Returns current capacity 415 size_t CodeHeap::capacity() const { 416 return _memory.committed_size(); 417 } 418 d 419 size_t CodeHeap::max_capacity() const { 420 return _memory.reserved_size(); 421 } 422 423 int CodeHeap::allocated_segments() const { 424 return (int)_next_segment; 425 } 426 427 size_t CodeHeap::allocated_capacity() const { 428 // size of used heap - size on freelist 429 return segments_to_size(_next_segment - _freelist_segments); 430 } 431 432 // Returns size of the unallocated heap block 433 size_t CodeHeap::heap_unallocated_capacity() const { 434 // Total number of segments - number currently used 435 return segments_to_size(_number_of_reserved_segments - _next_segment); 436 } 437 438 // Free list management 439 440 FreeBlock* CodeHeap::following_block(FreeBlock *b) { 441 return (FreeBlock*)(((address)b) + _segment_size * b->length()); 442 } 443 444 // Inserts block b after a 445 void CodeHeap::insert_after(FreeBlock* a, FreeBlock* b) { 446 assert(a != NULL && b != NULL, "must be real pointers"); 447 448 // Link b into the list after a 449 b->set_link(a->link()); 450 a->set_link(b); 451 452 // See if we can merge blocks 453 merge_right(b); // Try to make b bigger 454 merge_right(a); // Try to make a include b 455 } 456 457 // Try to merge this block with the following block 458 bool CodeHeap::merge_right(FreeBlock* a) { 459 assert(a->free(), "must be a free block"); 460 if (following_block(a) == a->link()) { 461 assert(a->link() != NULL && a->link()->free(), "must be free too"); 462 // Update block a to include the following block 463 a->set_length(a->length() + a->link()->length()); 464 a->set_link(a->link()->link()); 465 // Update find_start map 466 size_t beg = segment_for(a); 467 mark_segmap_as_used(beg, beg + a->length()); 468 invalidate(beg, beg + a->length(), sizeof(FreeBlock)); 469 _freelist_length--; 470 return true; 471 } 472 return false; 473 } 474 475 476 void CodeHeap::add_to_freelist(HeapBlock* a) { 477 FreeBlock* b = (FreeBlock*)a; 478 size_t bseg = segment_for(b); 479 _freelist_length++; 480 481 assert(b != _freelist, "cannot be removed twice"); 482 483 // Mark as free and update free space count 484 _freelist_segments += b->length(); 485 b->set_free(); 486 invalidate(bseg, bseg + b->length(), sizeof(FreeBlock)); 487 488 // First element in list? 489 if (_freelist == NULL) { 490 b->set_link(NULL); 491 _freelist = b; 492 return; 493 } 494 495 // Since the freelist is ordered (smaller addresses -> larger addresses) and the 496 // element we want to insert into the freelist has a smaller address than the first 497 // element, we can simply add 'b' as the first element and we are done. 498 if (b < _freelist) { 499 // Insert first in list 500 b->set_link(_freelist); 501 _freelist = b; 502 merge_right(_freelist); 503 return; 504 } 505 506 // Scan for right place to put into list. List 507 // is sorted by increasing addresses 508 FreeBlock* prev = _freelist; 509 FreeBlock* cur = _freelist->link(); 510 while(cur != NULL && cur < b) { 511 assert(prev < cur, "Freelist must be ordered"); 512 prev = cur; 513 cur = cur->link(); 514 } 515 assert((prev < b) && (cur == NULL || b < cur), "free-list must be ordered"); 516 insert_after(prev, b); 517 } 518 519 /** 520 * Search freelist for an entry on the list with the best fit. 521 * @return NULL, if no one was found 522 */ 523 HeapBlock* CodeHeap::search_freelist(size_t length) { 524 FreeBlock* found_block = NULL; 525 FreeBlock* found_prev = NULL; 526 size_t found_length = _next_segment; // max it out to begin with 527 528 HeapBlock* res = NULL; 529 FreeBlock* prev = NULL; 530 FreeBlock* cur = _freelist; 531 532 length = length < CodeCacheMinBlockLength ? CodeCacheMinBlockLength : length; 533 534 // Search for best-fitting block 535 while(cur != NULL) { 536 size_t cur_length = cur->length(); 537 if (cur_length == length) { 538 // We have a perfect fit 539 found_block = cur; 540 found_prev = prev; 541 found_length = cur_length; 542 break; 543 } else if ((cur_length > length) && (cur_length < found_length)) { 544 // This is a new, closer fit. Remember block, its previous element, and its length 545 found_block = cur; 546 found_prev = prev; 547 found_length = cur_length; 548 } 549 // Next element in list 550 prev = cur; 551 cur = cur->link(); 552 } 553 554 if (found_block == NULL) { 555 // None found 556 return NULL; 557 } 558 559 // Exact (or at least good enough) fit. Remove from list. 560 // Don't leave anything on the freelist smaller than CodeCacheMinBlockLength. 561 if (found_length - length < CodeCacheMinBlockLength) { 562 _freelist_length--; 563 length = found_length; 564 if (found_prev == NULL) { 565 assert(_freelist == found_block, "sanity check"); 566 _freelist = _freelist->link(); 567 } else { 568 assert((found_prev->link() == found_block), "sanity check"); 569 // Unmap element 570 found_prev->set_link(found_block->link()); 571 } 572 res = found_block; 573 } else { 574 // Truncate the free block and return the truncated part 575 // as new HeapBlock. The remaining free block does not 576 // need to be updated, except for it's length. Truncating 577 // the segment map does not invalidate the leading part. 578 res = split_block(found_block, found_length - length); 579 } 580 581 res->set_used(); 582 _freelist_segments -= length; 583 return res; 584 } 585 586 //---------------------------------------------------------------------------- 587 // Non-product code 588 589 #ifndef PRODUCT 590 591 void CodeHeap::print() { 592 tty->print_cr("The Heap"); 593 } 594 595 void CodeHeap::verify() { 596 if (VerifyCodeCache) { 597 size_t len = 0; 598 int count = 0; 599 for(FreeBlock* b = _freelist; b != NULL; b = b->link()) { 600 len += b->length(); 601 count++; 602 // Check if we have merged all free blocks 603 assert(merge_right(b) == false, "Missed merging opportunity"); 604 } 605 // Verify that freelist contains the right amount of free space 606 assert(len == _freelist_segments, "wrong freelist"); 607 608 for(HeapBlock* h = first_block(); h != NULL; h = next_block(h)) { 609 if (h->free()) count--; 610 } 611 // Verify that the freelist contains the same number of blocks 612 // than free blocks found on the full list. 613 assert(count == 0, "missing free blocks"); 614 615 //---< all free block memory must have been invalidated >--- 616 for(FreeBlock* b = _freelist; b != NULL; b = b->link()) { 617 for (char* c = (char*)b + sizeof(FreeBlock); c < (char*)b + segments_to_size(b->length()); c++) { 618 assert(*c == (char)badCodeHeapNewVal, "FreeBlock@" PTR_FORMAT "(" PTR_FORMAT ") not invalidated @byte %d", p2i(b), b->length(), (int)(c - (char*)b)); 619 } 620 } 621 622 // Verify segment map marking. 623 // All allocated segments, no matter if in a free or used block, 624 // must be marked "in use". 625 address seg_map = (address)_segmap.low(); 626 size_t nseg = 0; 627 for(HeapBlock* b = first_block(); b != NULL; b = next_block(b)) { 628 size_t seg1 = segment_for(b); 629 size_t segn = seg1 + b->length(); 630 for (size_t i = seg1; i < segn; i++) { 631 nseg++; 632 assert(!is_segment_unused(seg_map[i]), "CodeHeap: unused segment. %d [%d..%d], %s block", (int)i, (int)seg1, (int)segn, b->free()? "free":"used"); 633 } 634 } 635 assert(nseg == _next_segment, "CodeHeap: segment count mismatch. found %d, expected %d.", (int)nseg, (int)_next_segment); 636 637 // Verify that the number of free blocks is not out of hand. 638 static int free_block_threshold = 10000; 639 if (count > free_block_threshold) { 640 warning("CodeHeap: # of free blocks > %d", free_block_threshold); 641 // Double the warning limit 642 free_block_threshold *= 2; 643 } 644 } 645 } 646 647 #endif