third_party/tcmalloc/vendor/src/heap-profile-table.cc

   1 // Copyright (c) 2006, Google Inc.
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  29
  30 // ---
  31 // Author: Sanjay Ghemawat
  32 //         Maxim Lifantsev (refactoring)
  33 //
  34
  35 #include <config.h>
  36
  37 #ifdef HAVE_UNISTD_H
  38 #include <unistd.h>   // for write()
  39 #endif
  40 #include <fcntl.h>    // for open()
  41 #ifdef HAVE_GLOB_H
  42 #include <glob.h>
  43 #ifndef GLOB_NOMATCH  // true on some old cygwins
  44 # define GLOB_NOMATCH 0
  45 #endif
  46 #endif
  47 #ifdef HAVE_INTTYPES_H
  48 #include <inttypes.h> // for PRIxPTR
  49 #endif
  50 #ifdef HAVE_POLL_H
  51 #include <poll.h>
  52 #endif
  53 #include <errno.h>
  54 #include <stdarg.h>
  55 #include <string>
  56 #include <map>
  57 #include <algorithm>  // for sort(), equal(), and copy()
  58
  59 #include "heap-profile-table.h"
  60
  61 #include "base/logging.h"
  62 #include "raw_printer.h"
  63 #include "symbolize.h"
  64 #include <gperftools/stacktrace.h>
  65 #include <gperftools/malloc_hook.h>
  66 #include "memory_region_map.h"
  67 #include "base/commandlineflags.h"
  68 #include "base/logging.h"    // for the RawFD I/O commands
  69 #include "base/sysinfo.h"
  70
  71 using std::sort;
  72 using std::equal;
  73 using std::copy;
  74 using std::string;
  75 using std::map;
  76
  77 using tcmalloc::FillProcSelfMaps;   // from sysinfo.h
  78 using tcmalloc::DumpProcSelfMaps;   // from sysinfo.h
  79
  80 //----------------------------------------------------------------------
  81
  82 DEFINE_bool(cleanup_old_heap_profiles,
  83             EnvToBool("HEAP_PROFILE_CLEANUP", true),
  84             "At initialization time, delete old heap profiles.");
  85
  86 DEFINE_int32(heap_check_max_leaks,
  87              EnvToInt("HEAP_CHECK_MAX_LEAKS", 20),
  88              "The maximum number of leak reports to print.");
  89
  90 //----------------------------------------------------------------------
  91
  92 // header of the dumped heap profile
  93 static const char kProfileHeader[] = "heap profile: ";
  94 static const char kProcSelfMapsHeader[] = "\nMAPPED_LIBRARIES:\n";
  95
  96 //----------------------------------------------------------------------
  97
  98 const char HeapProfileTable::kFileExt[] = ".heap";
  99
 100 //----------------------------------------------------------------------
 101
 102 // Size for alloc_table_ and mmap_table_.
 103 static const int kHashTableSize = 179999;
 104 /*static*/ const int HeapProfileTable::kMaxStackDepth;
 105
 106 //----------------------------------------------------------------------
 107
 108 // We strip out different number of stack frames in debug mode
 109 // because less inlining happens in that case
 110 #ifdef NDEBUG
 111 static const int kStripFrames = 2;
 112 #else
 113 static const int kStripFrames = 3;
 114 #endif
 115
 116 // For sorting Stats or Buckets by in-use space
 117 static bool ByAllocatedSpace(HeapProfileTable::Stats* a,
 118                              HeapProfileTable::Stats* b) {
 119   // Return true iff "a" has more allocated space than "b"
 120   return (a->alloc_size - a->free_size) > (b->alloc_size - b->free_size);
 121 }
 122
 123 //----------------------------------------------------------------------
 124
 125 HeapProfileTable::HeapProfileTable(Allocator alloc, DeAllocator dealloc)
 126     : alloc_(alloc), dealloc_(dealloc) {
 127   // Initialize the overall profile stats.
 128   memset(&total_, 0, sizeof(total_));
 129
 130   // Make the malloc table.
 131   const int alloc_table_bytes = kHashTableSize * sizeof(*alloc_table_);
 132   alloc_table_ = reinterpret_cast<Bucket**>(alloc_(alloc_table_bytes));
 133   memset(alloc_table_, 0, alloc_table_bytes);
 134   num_alloc_buckets_ = 0;
 135
 136   // Initialize the mmap table.
 137   mmap_table_ = NULL;
 138   num_available_mmap_buckets_ = 0;
 139
 140   // Make malloc and mmap allocation maps.
 141   alloc_address_map_ =
 142       new(alloc_(sizeof(AllocationMap))) AllocationMap(alloc_, dealloc_);
 143   mmap_address_map_ = NULL;
 144 }
 145
 146 HeapProfileTable::~HeapProfileTable() {
 147   DeallocateBucketTable(alloc_table_);
 148   alloc_table_ = NULL;
 149   DeallocateBucketTable(mmap_table_);
 150   mmap_table_ = NULL;
 151   DeallocateAllocationMap(alloc_address_map_);
 152   alloc_address_map_ = NULL;
 153   DeallocateAllocationMap(mmap_address_map_);
 154   mmap_address_map_ = NULL;
 155 }
 156
 157 void HeapProfileTable::DeallocateAllocationMap(AllocationMap* allocation) {
 158   if (allocation != NULL) {
 159     alloc_address_map_->~AllocationMap();
 160     dealloc_(allocation);
 161   }
 162 }
 163
 164 void HeapProfileTable::DeallocateBucketTable(Bucket** table) {
 165   if (table != NULL) {
 166     for (int b = 0; b < kHashTableSize; b++) {
 167       for (Bucket* x = table[b]; x != 0; /**/) {
 168         Bucket* b = x;
 169         x = x->next;
 170         dealloc_(b->stack);
 171         dealloc_(b);
 172       }
 173     }
 174     dealloc_(table);
 175   }
 176 }
 177
 178 HeapProfileTable::Bucket* HeapProfileTable::GetBucket(
 179     int depth, const void* const key[], Bucket** table,
 180     int* bucket_count) {
 181   // Make hash-value
 182   uintptr_t h = 0;
 183   for (int i = 0; i < depth; i++) {
 184     h += reinterpret_cast<uintptr_t>(key[i]);
 185     h += h << 10;
 186     h ^= h >> 6;
 187   }
 188   h += h << 3;
 189   h ^= h >> 11;
 190
 191   // Lookup stack trace in table
 192   unsigned int buck = ((unsigned int) h) % kHashTableSize;
 193   for (Bucket* b = table[buck]; b != 0; b = b->next) {
 194     if ((b->hash == h) &&
 195         (b->depth == depth) &&
 196         equal(key, key + depth, b->stack)) {
 197       return b;
 198     }
 199   }
 200
 201   // Create new bucket
 202   const size_t key_size = sizeof(key[0]) * depth;
 203   const void** kcopy = reinterpret_cast<const void**>(alloc_(key_size));
 204   copy(key, key + depth, kcopy);
 205   Bucket* b = reinterpret_cast<Bucket*>(alloc_(sizeof(Bucket)));
 206   memset(b, 0, sizeof(*b));
 207   b->hash  = h;
 208   b->depth = depth;
 209   b->stack = kcopy;
 210   b->next  = table[buck];
 211   table[buck] = b;
 212   if (bucket_count != NULL) {
 213     ++(*bucket_count);
 214   }
 215   return b;
 216 }
 217
 218 int HeapProfileTable::GetCallerStackTrace(
 219     int skip_count, void* stack[kMaxStackDepth]) {
 220   return MallocHook::GetCallerStackTrace(
 221       stack, kMaxStackDepth, kStripFrames + skip_count + 1);
 222 }
 223
 224 void HeapProfileTable::RecordAlloc(
 225     const void* ptr, size_t bytes, int stack_depth,
 226     const void* const call_stack[]) {
 227   Bucket* b = GetBucket(stack_depth, call_stack, alloc_table_,
 228                         &num_alloc_buckets_);
 229   b->allocs++;
 230   b->alloc_size += bytes;
 231   total_.allocs++;
 232   total_.alloc_size += bytes;
 233
 234   AllocValue v;
 235   v.set_bucket(b);  // also did set_live(false); set_ignore(false)
 236   v.bytes = bytes;
 237   alloc_address_map_->Insert(ptr, v);
 238 }
 239
 240 void HeapProfileTable::RecordFree(const void* ptr) {
 241   AllocValue v;
 242   if (alloc_address_map_->FindAndRemove(ptr, &v)) {
 243     Bucket* b = v.bucket();
 244     b->frees++;
 245     b->free_size += v.bytes;
 246     total_.frees++;
 247     total_.free_size += v.bytes;
 248   }
 249 }
 250
 251 bool HeapProfileTable::FindAlloc(const void* ptr, size_t* object_size) const {
 252   const AllocValue* alloc_value = alloc_address_map_->Find(ptr);
 253   if (alloc_value != NULL) *object_size = alloc_value->bytes;
 254   return alloc_value != NULL;
 255 }
 256
 257 bool HeapProfileTable::FindAllocDetails(const void* ptr,
 258                                         AllocInfo* info) const {
 259   const AllocValue* alloc_value = alloc_address_map_->Find(ptr);
 260   if (alloc_value != NULL) {
 261     info->object_size = alloc_value->bytes;
 262     info->call_stack = alloc_value->bucket()->stack;
 263     info->stack_depth = alloc_value->bucket()->depth;
 264   }
 265   return alloc_value != NULL;
 266 }
 267
 268 bool HeapProfileTable::FindInsideAlloc(const void* ptr,
 269                                        size_t max_size,
 270                                        const void** object_ptr,
 271                                        size_t* object_size) const {
 272   const AllocValue* alloc_value =
 273     alloc_address_map_->FindInside(&AllocValueSize, max_size, ptr, object_ptr);
 274   if (alloc_value != NULL) *object_size = alloc_value->bytes;
 275   return alloc_value != NULL;
 276 }
 277
 278 bool HeapProfileTable::MarkAsLive(const void* ptr) {
 279   AllocValue* alloc = alloc_address_map_->FindMutable(ptr);
 280   if (alloc && !alloc->live()) {
 281     alloc->set_live(true);
 282     return true;
 283   }
 284   return false;
 285 }
 286
 287 void HeapProfileTable::MarkAsIgnored(const void* ptr) {
 288   AllocValue* alloc = alloc_address_map_->FindMutable(ptr);
 289   if (alloc) {
 290     alloc->set_ignore(true);
 291   }
 292 }
 293
 294 // We'd be happier using snprintfer, but we don't to reduce dependencies.
 295 int HeapProfileTable::UnparseBucket(const Bucket& b,
 296                                     char* buf, int buflen, int bufsize,
 297                                     const char* extra,
 298                                     Stats* profile_stats) {
 299   if (profile_stats != NULL) {
 300     profile_stats->allocs += b.allocs;
 301     profile_stats->alloc_size += b.alloc_size;
 302     profile_stats->frees += b.frees;
 303     profile_stats->free_size += b.free_size;
 304   }
 305   int printed =
 306     snprintf(buf + buflen, bufsize - buflen, "%6d: %8"PRId64" [%6d: %8"PRId64"] @%s",
 307              b.allocs - b.frees,
 308              b.alloc_size - b.free_size,
 309              b.allocs,
 310              b.alloc_size,
 311              extra);
 312   // If it looks like the snprintf failed, ignore the fact we printed anything
 313   if (printed < 0 || printed >= bufsize - buflen) return buflen;
 314   buflen += printed;
 315   for (int d = 0; d < b.depth; d++) {
 316     printed = snprintf(buf + buflen, bufsize - buflen, " 0x%08" PRIxPTR,
 317                        reinterpret_cast<uintptr_t>(b.stack[d]));
 318     if (printed < 0 || printed >= bufsize - buflen) return buflen;
 319     buflen += printed;
 320   }
 321   printed = snprintf(buf + buflen, bufsize - buflen, "\n");
 322   if (printed < 0 || printed >= bufsize - buflen) return buflen;
 323   buflen += printed;
 324   return buflen;
 325 }
 326
 327 HeapProfileTable::Bucket**
 328 HeapProfileTable::MakeSortedBucketList() const {
 329   Bucket** list = reinterpret_cast<Bucket**>(alloc_(sizeof(Bucket) *
 330       (num_alloc_buckets_ + num_available_mmap_buckets_)));
 331
 332   RAW_DCHECK(mmap_table_ != NULL || num_available_mmap_buckets_ == 0, "");
 333
 334   int n = 0;
 335
 336   for (int b = 0; b < kHashTableSize; b++) {
 337     for (Bucket* x = alloc_table_[b]; x != 0; x = x->next) {
 338       list[n++] = x;
 339     }
 340   }
 341   RAW_DCHECK(n == num_alloc_buckets_, "");
 342
 343   if (mmap_table_ != NULL) {
 344     for (int b = 0; b < kHashTableSize; b++) {
 345       for (Bucket* x = mmap_table_[b]; x != 0; x = x->next) {
 346         list[n++] = x;
 347       }
 348     }
 349   }
 350   RAW_DCHECK(n == num_alloc_buckets_ + num_available_mmap_buckets_, "");
 351
 352   sort(list, list + num_alloc_buckets_ + num_available_mmap_buckets_,
 353        ByAllocatedSpace);
 354
 355   return list;
 356 }
 357
 358 void HeapProfileTable::RefreshMMapData() {
 359   // Make the table
 360   static const int mmap_table_bytes = kHashTableSize * sizeof(*mmap_table_);
 361   if (mmap_table_ == NULL) {
 362     mmap_table_ = reinterpret_cast<Bucket**>(alloc_(mmap_table_bytes));
 363     memset(mmap_table_, 0, mmap_table_bytes);
 364   }
 365   num_available_mmap_buckets_ = 0;
 366
 367   ClearMMapData();
 368   mmap_address_map_ =
 369       new(alloc_(sizeof(AllocationMap))) AllocationMap(alloc_, dealloc_);
 370
 371   MemoryRegionMap::LockHolder l;
 372   for (MemoryRegionMap::RegionIterator r =
 373            MemoryRegionMap::BeginRegionLocked();
 374        r != MemoryRegionMap::EndRegionLocked(); ++r) {
 375     Bucket* b =
 376         GetBucket(r->call_stack_depth, r->call_stack, mmap_table_, NULL);
 377     if (b->alloc_size == 0) {
 378       num_available_mmap_buckets_ += 1;
 379     }
 380     b->allocs += 1;
 381     b->alloc_size += r->end_addr - r->start_addr;
 382
 383     AllocValue v;
 384     v.set_bucket(b);
 385     v.bytes = r->end_addr - r->start_addr;
 386     mmap_address_map_->Insert(reinterpret_cast<const void*>(r->start_addr), v);
 387   }
 388 }
 389
 390 void HeapProfileTable::ClearMMapData() {
 391   if (mmap_address_map_ != NULL) {
 392     mmap_address_map_->Iterate(ZeroBucketCountsIterator, this);
 393     mmap_address_map_->~AllocationMap();
 394     dealloc_(mmap_address_map_);
 395     mmap_address_map_ = NULL;
 396   }
 397 }
 398
 399 void HeapProfileTable::IterateOrderedAllocContexts(
 400     AllocContextIterator callback) const {
 401   Bucket** list = MakeSortedBucketList();
 402   AllocContextInfo info;
 403   for (int i = 0; i < num_alloc_buckets_; ++i) {
 404     *static_cast<Stats*>(&info) = *static_cast<Stats*>(list[i]);
 405     info.stack_depth = list[i]->depth;
 406     info.call_stack = list[i]->stack;
 407     callback(info);
 408   }
 409   dealloc_(list);
 410 }
 411
 412 int HeapProfileTable::FillOrderedProfile(char buf[], int size) const {
 413   Bucket** list = MakeSortedBucketList();
 414
 415   // Our file format is "bucket, bucket, ..., bucket, proc_self_maps_info".
 416   // In the cases buf is too small, we'd rather leave out the last
 417   // buckets than leave out the /proc/self/maps info.  To ensure that,
 418   // we actually print the /proc/self/maps info first, then move it to
 419   // the end of the buffer, then write the bucket info into whatever
 420   // is remaining, and then move the maps info one last time to close
 421   // any gaps.  Whew!
 422   int map_length = snprintf(buf, size, "%s", kProcSelfMapsHeader);
 423   if (map_length < 0 || map_length >= size) return 0;
 424   bool dummy;   // "wrote_all" -- did /proc/self/maps fit in its entirety?
 425   map_length += FillProcSelfMaps(buf + map_length, size - map_length, &dummy);
 426   RAW_DCHECK(map_length <= size, "");
 427   char* const map_start = buf + size - map_length;      // move to end
 428   memmove(map_start, buf, map_length);
 429   size -= map_length;
 430
 431   Stats stats;
 432   memset(&stats, 0, sizeof(stats));
 433   int bucket_length = snprintf(buf, size, "%s", kProfileHeader);
 434   if (bucket_length < 0 || bucket_length >= size) return 0;
 435   Bucket total_with_mmap(total_);
 436   if (mmap_table_ != NULL) {
 437     total_with_mmap.alloc_size += MemoryRegionMap::MapSize();
 438     total_with_mmap.free_size += MemoryRegionMap::UnmapSize();
 439   }
 440   bucket_length = UnparseBucket(total_with_mmap, buf, bucket_length, size,
 441                                 " heapprofile", &stats);
 442   for (int i = 0; i < num_alloc_buckets_; i++) {
 443     bucket_length = UnparseBucket(*list[i], buf, bucket_length, size, "",
 444                                   &stats);
 445   }
 446   RAW_DCHECK(bucket_length < size, "");
 447
 448   dealloc_(list);
 449
 450   RAW_DCHECK(buf + bucket_length <= map_start, "");
 451   memmove(buf + bucket_length, map_start, map_length);  // close the gap
 452
 453   return bucket_length + map_length;
 454 }
 455
 456 inline
 457 void HeapProfileTable::DumpNonLiveIterator(const void* ptr, AllocValue* v,
 458                                            const DumpArgs& args) {
 459   if (v->live()) {
 460     v->set_live(false);
 461     return;
 462   }
 463   if (v->ignore()) {
 464     return;
 465   }
 466   Bucket b;
 467   memset(&b, 0, sizeof(b));
 468   b.allocs = 1;
 469   b.alloc_size = v->bytes;
 470   b.depth = v->bucket()->depth;
 471   b.stack = v->bucket()->stack;
 472   char buf[1024];
 473   int len = UnparseBucket(b, buf, 0, sizeof(buf), "", args.profile_stats);
 474   RawWrite(args.fd, buf, len);
 475 }
 476
 477 inline void HeapProfileTable::ZeroBucketCountsIterator(
 478     const void* ptr, AllocValue* v, HeapProfileTable* heap_profile) {
 479   Bucket* b = v->bucket();
 480   if (b != NULL) {
 481     b->allocs = 0;
 482     b->alloc_size = 0;
 483     b->free_size = 0;
 484     b->frees = 0;
 485   }
 486 }
 487
 488 // Callback from NonLiveSnapshot; adds entry to arg->dest
 489 // if not the entry is not live and is not present in arg->base.
 490 void HeapProfileTable::AddIfNonLive(const void* ptr, AllocValue* v,
 491                                     AddNonLiveArgs* arg) {
 492   if (v->live()) {
 493     v->set_live(false);
 494   } else {
 495     if (arg->base != NULL && arg->base->map_.Find(ptr) != NULL) {
 496       // Present in arg->base, so do not save
 497     } else {
 498       arg->dest->Add(ptr, *v);
 499     }
 500   }
 501 }
 502
 503 bool HeapProfileTable::WriteProfile(const char* file_name,
 504                                     const Bucket& total,
 505                                     AllocationMap* allocations) {
 506   RAW_VLOG(1, "Dumping non-live heap profile to %s", file_name);
 507   RawFD fd = RawOpenForWriting(file_name);
 508   if (fd != kIllegalRawFD) {
 509     RawWrite(fd, kProfileHeader, strlen(kProfileHeader));
 510     char buf[512];
 511     int len = UnparseBucket(total, buf, 0, sizeof(buf), " heapprofile",
 512                             NULL);
 513     RawWrite(fd, buf, len);
 514     const DumpArgs args(fd, NULL);
 515     allocations->Iterate<const DumpArgs&>(DumpNonLiveIterator, args);
 516     RawWrite(fd, kProcSelfMapsHeader, strlen(kProcSelfMapsHeader));
 517     DumpProcSelfMaps(fd);
 518     RawClose(fd);
 519     return true;
 520   } else {
 521     RAW_LOG(ERROR, "Failed dumping filtered heap profile to %s", file_name);
 522     return false;
 523   }
 524 }
 525
 526 void HeapProfileTable::CleanupOldProfiles(const char* prefix) {
 527   if (!FLAGS_cleanup_old_heap_profiles)
 528     return;
 529   string pattern = string(prefix) + ".*" + kFileExt;
 530 #if defined(HAVE_GLOB_H)
 531   glob_t g;
 532   const int r = glob(pattern.c_str(), GLOB_ERR, NULL, &g);
 533   if (r == 0 || r == GLOB_NOMATCH) {
 534     const int prefix_length = strlen(prefix);
 535     for (int i = 0; i < g.gl_pathc; i++) {
 536       const char* fname = g.gl_pathv[i];
 537       if ((strlen(fname) >= prefix_length) &&
 538           (memcmp(fname, prefix, prefix_length) == 0)) {
 539         RAW_VLOG(1, "Removing old heap profile %s", fname);
 540         unlink(fname);
 541       }
 542     }
 543   }
 544   globfree(&g);
 545 #else   /* HAVE_GLOB_H */
 546   RAW_LOG(WARNING, "Unable to remove old heap profiles (can't run glob())");
 547 #endif
 548 }
 549
 550 HeapProfileTable::Snapshot* HeapProfileTable::TakeSnapshot() {
 551   Snapshot* s = new (alloc_(sizeof(Snapshot))) Snapshot(alloc_, dealloc_);
 552   alloc_address_map_->Iterate(AddToSnapshot, s);
 553   return s;
 554 }
 555
 556 void HeapProfileTable::ReleaseSnapshot(Snapshot* s) {
 557   s->~Snapshot();
 558   dealloc_(s);
 559 }
 560
 561 // Callback from TakeSnapshot; adds a single entry to snapshot
 562 void HeapProfileTable::AddToSnapshot(const void* ptr, AllocValue* v,
 563                                      Snapshot* snapshot) {
 564   snapshot->Add(ptr, *v);
 565 }
 566
 567 HeapProfileTable::Snapshot* HeapProfileTable::NonLiveSnapshot(
 568     Snapshot* base) {
 569   RAW_VLOG(2, "NonLiveSnapshot input: %d %d\n",
 570            int(total_.allocs - total_.frees),
 571            int(total_.alloc_size - total_.free_size));
 572
 573   Snapshot* s = new (alloc_(sizeof(Snapshot))) Snapshot(alloc_, dealloc_);
 574   AddNonLiveArgs args;
 575   args.dest = s;
 576   args.base = base;
 577   alloc_address_map_->Iterate<AddNonLiveArgs*>(AddIfNonLive, &args);
 578   RAW_VLOG(2, "NonLiveSnapshot output: %d %d\n",
 579            int(s->total_.allocs - s->total_.frees),
 580            int(s->total_.alloc_size - s->total_.free_size));
 581   return s;
 582 }
 583
 584 // Information kept per unique bucket seen
 585 struct HeapProfileTable::Snapshot::Entry {
 586   int count;
 587   int bytes;
 588   Bucket* bucket;
 589   Entry() : count(0), bytes(0) { }
 590
 591   // Order by decreasing bytes
 592   bool operator<(const Entry& x) const {
 593     return this->bytes > x.bytes;
 594   }
 595 };
 596
 597 // State used to generate leak report.  We keep a mapping from Bucket pointer
 598 // the collected stats for that bucket.
 599 struct HeapProfileTable::Snapshot::ReportState {
 600   map<Bucket*, Entry> buckets_;
 601 };
 602
 603 // Callback from ReportLeaks; updates ReportState.
 604 void HeapProfileTable::Snapshot::ReportCallback(const void* ptr,
 605                                                 AllocValue* v,
 606                                                 ReportState* state) {
 607   Entry* e = &state->buckets_[v->bucket()]; // Creates empty Entry first time
 608   e->bucket = v->bucket();
 609   e->count++;
 610   e->bytes += v->bytes;
 611 }
 612
 613 void HeapProfileTable::Snapshot::ReportLeaks(const char* checker_name,
 614                                              const char* filename,
 615                                              bool should_symbolize) {
 616   // This is only used by the heap leak checker, but is intimately
 617   // tied to the allocation map that belongs in this module and is
 618   // therefore placed here.
 619   RAW_LOG(ERROR, "Leak check %s detected leaks of %"PRIuS" bytes "
 620           "in %"PRIuS" objects",
 621           checker_name,
 622           size_t(total_.alloc_size),
 623           size_t(total_.allocs));
 624
 625   // Group objects by Bucket
 626   ReportState state;
 627   map_.Iterate(&ReportCallback, &state);
 628
 629   // Sort buckets by decreasing leaked size
 630   const int n = state.buckets_.size();
 631   Entry* entries = new Entry[n];
 632   int dst = 0;
 633   for (map<Bucket*,Entry>::const_iterator iter = state.buckets_.begin();
 634        iter != state.buckets_.end();
 635        ++iter) {
 636     entries[dst++] = iter->second;
 637   }
 638   sort(entries, entries + n);
 639
 640   // Report a bounded number of leaks to keep the leak report from
 641   // growing too long.
 642   const int to_report =
 643       (FLAGS_heap_check_max_leaks > 0 &&
 644        n > FLAGS_heap_check_max_leaks) ? FLAGS_heap_check_max_leaks : n;
 645   RAW_LOG(ERROR, "The %d largest leaks:", to_report);
 646
 647   // Print
 648   SymbolTable symbolization_table;
 649   for (int i = 0; i < to_report; i++) {
 650     const Entry& e = entries[i];
 651     for (int j = 0; j < e.bucket->depth; j++) {
 652       symbolization_table.Add(e.bucket->stack[j]);
 653     }
 654   }
 655   static const int kBufSize = 2<<10;
 656   char buffer[kBufSize];
 657   if (should_symbolize)
 658     symbolization_table.Symbolize();
 659   for (int i = 0; i < to_report; i++) {
 660     const Entry& e = entries[i];
 661     base::RawPrinter printer(buffer, kBufSize);
 662     printer.Printf("Leak of %d bytes in %d objects allocated from:\n",
 663                    e.bytes, e.count);
 664     for (int j = 0; j < e.bucket->depth; j++) {
 665       const void* pc = e.bucket->stack[j];
 666       printer.Printf("\t@ %"PRIxPTR" %s\n",
 667           reinterpret_cast<uintptr_t>(pc), symbolization_table.GetSymbol(pc));
 668     }
 669     RAW_LOG(ERROR, "%s", buffer);
 670   }
 671
 672   if (to_report < n) {
 673     RAW_LOG(ERROR, "Skipping leaks numbered %d..%d",
 674             to_report, n-1);
 675   }
 676   delete[] entries;
 677
 678   // TODO: Dump the sorted Entry list instead of dumping raw data?
 679   // (should be much shorter)
 680   if (!HeapProfileTable::WriteProfile(filename, total_, &map_)) {
 681     RAW_LOG(ERROR, "Could not write pprof profile to %s", filename);
 682   }
 683 }
 684
 685 void HeapProfileTable::Snapshot::ReportObject(const void* ptr,
 686                                               AllocValue* v,
 687                                               char* unused) {
 688   // Perhaps also log the allocation stack trace (unsymbolized)
 689   // on this line in case somebody finds it useful.
 690   RAW_LOG(ERROR, "leaked %"PRIuS" byte object %p", v->bytes, ptr);
 691 }
 692
 693 void HeapProfileTable::Snapshot::ReportIndividualObjects() {
 694   char unused;
 695   map_.Iterate(ReportObject, &unused);
 696 }