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

   1 // Copyright (c) 2006, Google Inc.
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  28 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  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 static const int kHashTableSize = 179999;   // Size for bucket_table_.
 103 // GCC requires this declaration, but MSVC does not allow it.
 104 #if !defined(COMPILER_MSVC)
 105 /*static*/ const int HeapProfileTable::kMaxStackDepth;
 106 #endif
 107
 108 //----------------------------------------------------------------------
 109
 110 // We strip out different number of stack frames in debug mode
 111 // because less inlining happens in that case
 112 #ifdef NDEBUG
 113 static const int kStripFrames = 2;
 114 #else
 115 static const int kStripFrames = 3;
 116 #endif
 117
 118 // For sorting Stats or Buckets by in-use space
 119 static bool ByAllocatedSpace(HeapProfileTable::Stats* a,
 120                              HeapProfileTable::Stats* b) {
 121   // Return true iff "a" has more allocated space than "b"
 122   return (a->alloc_size - a->free_size) > (b->alloc_size - b->free_size);
 123 }
 124
 125 //----------------------------------------------------------------------
 126
 127 HeapProfileTable::HeapProfileTable(Allocator alloc,
 128                                    DeAllocator dealloc,
 129                                    bool profile_mmap)
 130     : alloc_(alloc),
 131       dealloc_(dealloc),
 132       bucket_table_(NULL),
 133       profile_mmap_(profile_mmap),
 134       num_buckets_(0),
 135       address_map_(NULL) {
 136   // Make a hash table for buckets.
 137   const int table_bytes = kHashTableSize * sizeof(*bucket_table_);
 138   bucket_table_ = static_cast<Bucket**>(alloc_(table_bytes));
 139   memset(bucket_table_, 0, table_bytes);
 140
 141   // Make an allocation map.
 142   address_map_ =
 143       new(alloc_(sizeof(AllocationMap))) AllocationMap(alloc_, dealloc_);
 144
 145   // Initialize.
 146   memset(&total_, 0, sizeof(total_));
 147   num_buckets_ = 0;
 148 }
 149
 150 HeapProfileTable::~HeapProfileTable() {
 151   // Free the allocation map.
 152   address_map_->~AllocationMap();
 153   dealloc_(address_map_);
 154   address_map_ = NULL;
 155
 156   // Free the hash table.
 157   for (int i = 0; i < kHashTableSize; i++) {
 158     for (Bucket* curr = bucket_table_[i]; curr != 0; /**/) {
 159       Bucket* bucket = curr;
 160       curr = curr->next;
 161       dealloc_(bucket->stack);
 162       dealloc_(bucket);
 163     }
 164   }
 165   dealloc_(bucket_table_);
 166   bucket_table_ = NULL;
 167 }
 168
 169 HeapProfileTable::Bucket* HeapProfileTable::GetBucket(int depth,
 170                                                       const void* const key[]) {
 171   // Make hash-value
 172   uintptr_t h = 0;
 173   for (int i = 0; i < depth; i++) {
 174     h += reinterpret_cast<uintptr_t>(key[i]);
 175     h += h << 10;
 176     h ^= h >> 6;
 177   }
 178   h += h << 3;
 179   h ^= h >> 11;
 180
 181   // Lookup stack trace in table
 182   unsigned int buck = ((unsigned int) h) % kHashTableSize;
 183   for (Bucket* b = bucket_table_[buck]; b != 0; b = b->next) {
 184     if ((b->hash == h) &&
 185         (b->depth == depth) &&
 186         equal(key, key + depth, b->stack)) {
 187       return b;
 188     }
 189   }
 190
 191   // Create new bucket
 192   const size_t key_size = sizeof(key[0]) * depth;
 193   const void** kcopy = reinterpret_cast<const void**>(alloc_(key_size));
 194   copy(key, key + depth, kcopy);
 195   Bucket* b = reinterpret_cast<Bucket*>(alloc_(sizeof(Bucket)));
 196   memset(b, 0, sizeof(*b));
 197   b->hash  = h;
 198   b->depth = depth;
 199   b->stack = kcopy;
 200   b->next  = bucket_table_[buck];
 201   bucket_table_[buck] = b;
 202   num_buckets_++;
 203   return b;
 204 }
 205
 206 int HeapProfileTable::GetCallerStackTrace(
 207     int skip_count, void* stack[kMaxStackDepth]) {
 208   return MallocHook::GetCallerStackTrace(
 209       stack, kMaxStackDepth, kStripFrames + skip_count + 1);
 210 }
 211
 212 void HeapProfileTable::RecordAlloc(
 213     const void* ptr, size_t bytes, int stack_depth,
 214     const void* const call_stack[]) {
 215   Bucket* b = GetBucket(stack_depth, call_stack);
 216   b->allocs++;
 217   b->alloc_size += bytes;
 218   total_.allocs++;
 219   total_.alloc_size += bytes;
 220
 221   AllocValue v;
 222   v.set_bucket(b);  // also did set_live(false); set_ignore(false)
 223   v.bytes = bytes;
 224   address_map_->Insert(ptr, v);
 225 }
 226
 227 void HeapProfileTable::RecordFree(const void* ptr) {
 228   AllocValue v;
 229   if (address_map_->FindAndRemove(ptr, &v)) {
 230     Bucket* b = v.bucket();
 231     b->frees++;
 232     b->free_size += v.bytes;
 233     total_.frees++;
 234     total_.free_size += v.bytes;
 235   }
 236 }
 237
 238 bool HeapProfileTable::FindAlloc(const void* ptr, size_t* object_size) const {
 239   const AllocValue* alloc_value = address_map_->Find(ptr);
 240   if (alloc_value != NULL) *object_size = alloc_value->bytes;
 241   return alloc_value != NULL;
 242 }
 243
 244 bool HeapProfileTable::FindAllocDetails(const void* ptr,
 245                                         AllocInfo* info) const {
 246   const AllocValue* alloc_value = address_map_->Find(ptr);
 247   if (alloc_value != NULL) {
 248     info->object_size = alloc_value->bytes;
 249     info->call_stack = alloc_value->bucket()->stack;
 250     info->stack_depth = alloc_value->bucket()->depth;
 251   }
 252   return alloc_value != NULL;
 253 }
 254
 255 bool HeapProfileTable::FindInsideAlloc(const void* ptr,
 256                                        size_t max_size,
 257                                        const void** object_ptr,
 258                                        size_t* object_size) const {
 259   const AllocValue* alloc_value =
 260     address_map_->FindInside(&AllocValueSize, max_size, ptr, object_ptr);
 261   if (alloc_value != NULL) *object_size = alloc_value->bytes;
 262   return alloc_value != NULL;
 263 }
 264
 265 bool HeapProfileTable::MarkAsLive(const void* ptr) {
 266   AllocValue* alloc = address_map_->FindMutable(ptr);
 267   if (alloc && !alloc->live()) {
 268     alloc->set_live(true);
 269     return true;
 270   }
 271   return false;
 272 }
 273
 274 void HeapProfileTable::MarkAsIgnored(const void* ptr) {
 275   AllocValue* alloc = address_map_->FindMutable(ptr);
 276   if (alloc) {
 277     alloc->set_ignore(true);
 278   }
 279 }
 280
 281 void HeapProfileTable::IterateAllocationAddresses(AddressIterator f,
 282                                                   void* data) {
 283   const AllocationAddressIteratorArgs args(f, data);
 284   address_map_->Iterate<const AllocationAddressIteratorArgs&>(
 285       AllocationAddressesIterator, args);
 286 }
 287
 288 void HeapProfileTable::MarkCurrentAllocations(AllocationMark mark) {
 289   const MarkArgs args(mark, true);
 290   address_map_->Iterate<const MarkArgs&>(MarkIterator, args);
 291 }
 292
 293 void HeapProfileTable::MarkUnmarkedAllocations(AllocationMark mark) {
 294   const MarkArgs args(mark, false);
 295   address_map_->Iterate<const MarkArgs&>(MarkIterator, args);
 296 }
 297
 298 // We'd be happier using snprintfer, but we don't to reduce dependencies.
 299 int HeapProfileTable::UnparseBucket(const Bucket& b,
 300                                     char* buf, int buflen, int bufsize,
 301                                     const char* extra,
 302                                     Stats* profile_stats) {
 303   if (profile_stats != NULL) {
 304     profile_stats->allocs += b.allocs;
 305     profile_stats->alloc_size += b.alloc_size;
 306     profile_stats->frees += b.frees;
 307     profile_stats->free_size += b.free_size;
 308   }
 309   int printed =
 310     snprintf(buf + buflen, bufsize - buflen,
 311              "%6d: %8" PRId64 " [%6d: %8" PRId64 "] @%s",
 312              b.allocs - b.frees,
 313              b.alloc_size - b.free_size,
 314              b.allocs,
 315              b.alloc_size,
 316              extra);
 317   // If it looks like the snprintf failed, ignore the fact we printed anything
 318   if (printed < 0 || printed >= bufsize - buflen) return buflen;
 319   buflen += printed;
 320   for (int d = 0; d < b.depth; d++) {
 321     printed = snprintf(buf + buflen, bufsize - buflen, " 0x%08" PRIxPTR,
 322                        reinterpret_cast<uintptr_t>(b.stack[d]));
 323     if (printed < 0 || printed >= bufsize - buflen) return buflen;
 324     buflen += printed;
 325   }
 326   printed = snprintf(buf + buflen, bufsize - buflen, "\n");
 327   if (printed < 0 || printed >= bufsize - buflen) return buflen;
 328   buflen += printed;
 329   return buflen;
 330 }
 331
 332 HeapProfileTable::Bucket**
 333 HeapProfileTable::MakeSortedBucketList() const {
 334   Bucket** list = static_cast<Bucket**>(alloc_(sizeof(Bucket) * num_buckets_));
 335
 336   int bucket_count = 0;
 337   for (int i = 0; i < kHashTableSize; i++) {
 338     for (Bucket* curr = bucket_table_[i]; curr != 0; curr = curr->next) {
 339       list[bucket_count++] = curr;
 340     }
 341   }
 342   RAW_DCHECK(bucket_count == num_buckets_, "");
 343
 344   sort(list, list + num_buckets_, ByAllocatedSpace);
 345
 346   return list;
 347 }
 348
 349 void HeapProfileTable::DumpMarkedObjects(AllocationMark mark,
 350                                          const char* file_name) {
 351   RawFD fd = RawOpenForWriting(file_name);
 352   if (fd == kIllegalRawFD) {
 353     RAW_LOG(ERROR, "Failed dumping live objects to %s", file_name);
 354     return;
 355   }
 356   const DumpMarkedArgs args(fd, mark);
 357   address_map_->Iterate<const DumpMarkedArgs&>(DumpMarkedIterator, args);
 358   RawClose(fd);
 359 }
 360
 361 void HeapProfileTable::IterateOrderedAllocContexts(
 362     AllocContextIterator callback) const {
 363   Bucket** list = MakeSortedBucketList();
 364   AllocContextInfo info;
 365   for (int i = 0; i < num_buckets_; ++i) {
 366     *static_cast<Stats*>(&info) = *static_cast<Stats*>(list[i]);
 367     info.stack_depth = list[i]->depth;
 368     info.call_stack = list[i]->stack;
 369     callback(info);
 370   }
 371   dealloc_(list);
 372 }
 373
 374 int HeapProfileTable::FillOrderedProfile(char buf[], int size) const {
 375   Bucket** list = MakeSortedBucketList();
 376
 377   // Our file format is "bucket, bucket, ..., bucket, proc_self_maps_info".
 378   // In the cases buf is too small, we'd rather leave out the last
 379   // buckets than leave out the /proc/self/maps info.  To ensure that,
 380   // we actually print the /proc/self/maps info first, then move it to
 381   // the end of the buffer, then write the bucket info into whatever
 382   // is remaining, and then move the maps info one last time to close
 383   // any gaps.  Whew!
 384   int map_length = snprintf(buf, size, "%s", kProcSelfMapsHeader);
 385   if (map_length < 0 || map_length >= size) return 0;
 386   bool dummy;   // "wrote_all" -- did /proc/self/maps fit in its entirety?
 387   map_length += FillProcSelfMaps(buf + map_length, size - map_length, &dummy);
 388   RAW_DCHECK(map_length <= size, "");
 389   char* const map_start = buf + size - map_length;      // move to end
 390   memmove(map_start, buf, map_length);
 391   size -= map_length;
 392
 393   Stats stats;
 394   memset(&stats, 0, sizeof(stats));
 395   int bucket_length = snprintf(buf, size, "%s", kProfileHeader);
 396   if (bucket_length < 0 || bucket_length >= size) return 0;
 397   bucket_length = UnparseBucket(total_, buf, bucket_length, size,
 398                                 " heapprofile", &stats);
 399
 400   // Dump the mmap list first.
 401   if (profile_mmap_) {
 402     BufferArgs buffer(buf, bucket_length, size);
 403     MemoryRegionMap::IterateBuckets<BufferArgs*>(DumpBucketIterator, &buffer);
 404     bucket_length = buffer.buflen;
 405   }
 406
 407   for (int i = 0; i < num_buckets_; i++) {
 408     bucket_length = UnparseBucket(*list[i], buf, bucket_length, size, "",
 409                                   &stats);
 410   }
 411   RAW_DCHECK(bucket_length < size, "");
 412
 413   dealloc_(list);
 414
 415   RAW_DCHECK(buf + bucket_length <= map_start, "");
 416   memmove(buf + bucket_length, map_start, map_length);  // close the gap
 417
 418   return bucket_length + map_length;
 419 }
 420
 421 // static
 422 void HeapProfileTable::DumpBucketIterator(const Bucket* bucket,
 423                                           BufferArgs* args) {
 424   args->buflen = UnparseBucket(*bucket, args->buf, args->buflen, args->bufsize,
 425                                "", NULL);
 426 }
 427
 428 inline
 429 void HeapProfileTable::DumpNonLiveIterator(const void* ptr, AllocValue* v,
 430                                            const DumpArgs& args) {
 431   if (v->live()) {
 432     v->set_live(false);
 433     return;
 434   }
 435   if (v->ignore()) {
 436     return;
 437   }
 438   Bucket b;
 439   memset(&b, 0, sizeof(b));
 440   b.allocs = 1;
 441   b.alloc_size = v->bytes;
 442   b.depth = v->bucket()->depth;
 443   b.stack = v->bucket()->stack;
 444   char buf[1024];
 445   int len = UnparseBucket(b, buf, 0, sizeof(buf), "", args.profile_stats);
 446   RawWrite(args.fd, buf, len);
 447 }
 448
 449 inline
 450 void HeapProfileTable::DumpMarkedIterator(const void* ptr, AllocValue* v,
 451                                           const DumpMarkedArgs& args) {
 452   if (v->mark() != args.mark)
 453     return;
 454   Bucket b;
 455   memset(&b, 0, sizeof(b));
 456   b.allocs = 1;
 457   b.alloc_size = v->bytes;
 458   b.depth = v->bucket()->depth;
 459   b.stack = v->bucket()->stack;
 460   char addr[16];
 461   snprintf(addr, 16, "0x%08" PRIxPTR, reinterpret_cast<uintptr_t>(ptr));
 462   char buf[1024];
 463   int len = UnparseBucket(b, buf, 0, sizeof(buf), addr, NULL);
 464   RawWrite(args.fd, buf, len);
 465 }
 466
 467 inline
 468 void HeapProfileTable::AllocationAddressesIterator(
 469     const void* ptr,
 470     AllocValue* v,
 471     const AllocationAddressIteratorArgs& args) {
 472   args.callback(args.data, ptr);
 473 }
 474
 475 inline
 476 void HeapProfileTable::MarkIterator(const void* ptr, AllocValue* v,
 477                                     const MarkArgs& args) {
 478   if (!args.mark_all && v->mark() != UNMARKED)
 479     return;
 480   v->set_mark(args.mark);
 481 }
 482
 483 // Callback from NonLiveSnapshot; adds entry to arg->dest
 484 // if not the entry is not live and is not present in arg->base.
 485 void HeapProfileTable::AddIfNonLive(const void* ptr, AllocValue* v,
 486                                     AddNonLiveArgs* arg) {
 487   if (v->live()) {
 488     v->set_live(false);
 489   } else {
 490     if (arg->base != NULL && arg->base->map_.Find(ptr) != NULL) {
 491       // Present in arg->base, so do not save
 492     } else {
 493       arg->dest->Add(ptr, *v);
 494     }
 495   }
 496 }
 497
 498 bool HeapProfileTable::WriteProfile(const char* file_name,
 499                                     const Bucket& total,
 500                                     AllocationMap* allocations) {
 501   RAW_VLOG(1, "Dumping non-live heap profile to %s", file_name);
 502   RawFD fd = RawOpenForWriting(file_name);
 503   if (fd == kIllegalRawFD) {
 504     RAW_LOG(ERROR, "Failed dumping filtered heap profile to %s", file_name);
 505     return false;
 506   }
 507   RawWrite(fd, kProfileHeader, strlen(kProfileHeader));
 508   char buf[512];
 509   int len = UnparseBucket(total, buf, 0, sizeof(buf), " heapprofile",
 510                           NULL);
 511   RawWrite(fd, buf, len);
 512   const DumpArgs args(fd, NULL);
 513   allocations->Iterate<const DumpArgs&>(DumpNonLiveIterator, args);
 514   RawWrite(fd, kProcSelfMapsHeader, strlen(kProcSelfMapsHeader));
 515   DumpProcSelfMaps(fd);
 516   RawClose(fd);
 517   return true;
 518 }
 519
 520 void HeapProfileTable::CleanupOldProfiles(const char* prefix) {
 521   if (!FLAGS_cleanup_old_heap_profiles)
 522     return;
 523   char buf[1000];
 524   snprintf(buf, 1000,"%s.%05d.", prefix, getpid());
 525   string pattern = string(buf) + ".*" + kFileExt;
 526
 527 #if defined(HAVE_GLOB_H)
 528   glob_t g;
 529   const int r = glob(pattern.c_str(), GLOB_ERR, NULL, &g);
 530   if (r == 0 || r == GLOB_NOMATCH) {
 531     const int prefix_length = strlen(prefix);
 532     for (int i = 0; i < g.gl_pathc; i++) {
 533       const char* fname = g.gl_pathv[i];
 534       if ((strlen(fname) >= prefix_length) &&
 535           (memcmp(fname, prefix, prefix_length) == 0)) {
 536         RAW_VLOG(1, "Removing old heap profile %s", fname);
 537         unlink(fname);
 538       }
 539     }
 540   }
 541   globfree(&g);
 542 #else   /* HAVE_GLOB_H */
 543   RAW_LOG(WARNING, "Unable to remove old heap profiles (can't run glob())");
 544 #endif
 545 }
 546
 547 HeapProfileTable::Snapshot* HeapProfileTable::TakeSnapshot() {
 548   Snapshot* s = new (alloc_(sizeof(Snapshot))) Snapshot(alloc_, dealloc_);
 549   address_map_->Iterate(AddToSnapshot, s);
 550   return s;
 551 }
 552
 553 void HeapProfileTable::ReleaseSnapshot(Snapshot* s) {
 554   s->~Snapshot();
 555   dealloc_(s);
 556 }
 557
 558 // Callback from TakeSnapshot; adds a single entry to snapshot
 559 void HeapProfileTable::AddToSnapshot(const void* ptr, AllocValue* v,
 560                                      Snapshot* snapshot) {
 561   snapshot->Add(ptr, *v);
 562 }
 563
 564 HeapProfileTable::Snapshot* HeapProfileTable::NonLiveSnapshot(
 565     Snapshot* base) {
 566   RAW_VLOG(2, "NonLiveSnapshot input: %d %d\n",
 567            int(total_.allocs - total_.frees),
 568            int(total_.alloc_size - total_.free_size));
 569
 570   Snapshot* s = new (alloc_(sizeof(Snapshot))) Snapshot(alloc_, dealloc_);
 571   AddNonLiveArgs args;
 572   args.dest = s;
 573   args.base = base;
 574   address_map_->Iterate<AddNonLiveArgs*>(AddIfNonLive, &args);
 575   RAW_VLOG(2, "NonLiveSnapshot output: %d %d\n",
 576            int(s->total_.allocs - s->total_.frees),
 577            int(s->total_.alloc_size - s->total_.free_size));
 578   return s;
 579 }
 580
 581 // Information kept per unique bucket seen
 582 struct HeapProfileTable::Snapshot::Entry {
 583   int count;
 584   int bytes;
 585   Bucket* bucket;
 586   Entry() : count(0), bytes(0) { }
 587
 588   // Order by decreasing bytes
 589   bool operator<(const Entry& x) const {
 590     return this->bytes > x.bytes;
 591   }
 592 };
 593
 594 // State used to generate leak report.  We keep a mapping from Bucket pointer
 595 // the collected stats for that bucket.
 596 struct HeapProfileTable::Snapshot::ReportState {
 597   map<Bucket*, Entry> buckets_;
 598 };
 599
 600 // Callback from ReportLeaks; updates ReportState.
 601 void HeapProfileTable::Snapshot::ReportCallback(const void* ptr,
 602                                                 AllocValue* v,
 603                                                 ReportState* state) {
 604   Entry* e = &state->buckets_[v->bucket()]; // Creates empty Entry first time
 605   e->bucket = v->bucket();
 606   e->count++;
 607   e->bytes += v->bytes;
 608 }
 609
 610 void HeapProfileTable::Snapshot::ReportLeaks(const char* checker_name,
 611                                              const char* filename,
 612                                              bool should_symbolize) {
 613   // This is only used by the heap leak checker, but is intimately
 614   // tied to the allocation map that belongs in this module and is
 615   // therefore placed here.
 616   RAW_LOG(ERROR, "Leak check %s detected leaks of %" PRIuS " bytes "
 617           "in %" PRIuS " objects",
 618           checker_name,
 619           size_t(total_.alloc_size),
 620           size_t(total_.allocs));
 621
 622   // Group objects by Bucket
 623   ReportState state;
 624   map_.Iterate(&ReportCallback, &state);
 625
 626   // Sort buckets by decreasing leaked size
 627   const int n = state.buckets_.size();
 628   Entry* entries = new Entry[n];
 629   int dst = 0;
 630   for (map<Bucket*,Entry>::const_iterator iter = state.buckets_.begin();
 631        iter != state.buckets_.end();
 632        ++iter) {
 633     entries[dst++] = iter->second;
 634   }
 635   sort(entries, entries + n);
 636
 637   // Report a bounded number of leaks to keep the leak report from
 638   // growing too long.
 639   const int to_report =
 640       (FLAGS_heap_check_max_leaks > 0 &&
 641        n > FLAGS_heap_check_max_leaks) ? FLAGS_heap_check_max_leaks : n;
 642   RAW_LOG(ERROR, "The %d largest leaks:", to_report);
 643
 644   // Print
 645   SymbolTable symbolization_table;
 646   for (int i = 0; i < to_report; i++) {
 647     const Entry& e = entries[i];
 648     for (int j = 0; j < e.bucket->depth; j++) {
 649       symbolization_table.Add(e.bucket->stack[j]);
 650     }
 651   }
 652   static const int kBufSize = 2<<10;
 653   char buffer[kBufSize];
 654   if (should_symbolize)
 655     symbolization_table.Symbolize();
 656   for (int i = 0; i < to_report; i++) {
 657     const Entry& e = entries[i];
 658     base::RawPrinter printer(buffer, kBufSize);
 659     printer.Printf("Leak of %d bytes in %d objects allocated from:\n",
 660                    e.bytes, e.count);
 661     for (int j = 0; j < e.bucket->depth; j++) {
 662       const void* pc = e.bucket->stack[j];
 663       printer.Printf("\t@ %" PRIxPTR " %s\n",
 664           reinterpret_cast<uintptr_t>(pc), symbolization_table.GetSymbol(pc));
 665     }
 666     RAW_LOG(ERROR, "%s", buffer);
 667   }
 668
 669   if (to_report < n) {
 670     RAW_LOG(ERROR, "Skipping leaks numbered %d..%d",
 671             to_report, n-1);
 672   }
 673   delete[] entries;
 674
 675   // TODO: Dump the sorted Entry list instead of dumping raw data?
 676   // (should be much shorter)
 677   if (!HeapProfileTable::WriteProfile(filename, total_, &map_)) {
 678     RAW_LOG(ERROR, "Could not write pprof profile to %s", filename);
 679   }
 680 }
 681
 682 void HeapProfileTable::Snapshot::ReportObject(const void* ptr,
 683                                               AllocValue* v,
 684                                               char* unused) {
 685   // Perhaps also log the allocation stack trace (unsymbolized)
 686   // on this line in case somebody finds it useful.
 687   RAW_LOG(ERROR, "leaked %" PRIuS " byte object %p", v->bytes, ptr);
 688 }
 689
 690 void HeapProfileTable::Snapshot::ReportIndividualObjects() {
 691   char unused;
 692   map_.Iterate(ReportObject, &unused);
 693 }