third_party/tcmalloc/chromium/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 #if defined(TYPE_PROFILING)
  96 static const char kTypeProfileStatsHeader[] = "type statistics:\n";
  97 #endif  // defined(TYPE_PROFILING)
  98
  99 //----------------------------------------------------------------------
 100
 101 const char HeapProfileTable::kFileExt[] = ".heap";
 102
 103 //----------------------------------------------------------------------
 104
 105 static const int kHashTableSize = 179999;   // Size for bucket_table_.
 106 /*static*/ const int HeapProfileTable::kMaxStackDepth;
 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, true);
 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, "%6d: %8"PRId64" [%6d: %8"PRId64"] @%s",
 311              b.allocs - b.frees,
 312              b.alloc_size - b.free_size,
 313              b.allocs,
 314              b.alloc_size,
 315              extra);
 316   // If it looks like the snprintf failed, ignore the fact we printed anything
 317   if (printed < 0 || printed >= bufsize - buflen) return buflen;
 318   buflen += printed;
 319   for (int d = 0; d < b.depth; d++) {
 320     printed = snprintf(buf + buflen, bufsize - buflen, " 0x%08" PRIxPTR,
 321                        reinterpret_cast<uintptr_t>(b.stack[d]));
 322     if (printed < 0 || printed >= bufsize - buflen) return buflen;
 323     buflen += printed;
 324   }
 325   printed = snprintf(buf + buflen, bufsize - buflen, "\n");
 326   if (printed < 0 || printed >= bufsize - buflen) return buflen;
 327   buflen += printed;
 328   return buflen;
 329 }
 330
 331 HeapProfileTable::Bucket**
 332 HeapProfileTable::MakeSortedBucketList() const {
 333   Bucket** list = static_cast<Bucket**>(alloc_(sizeof(Bucket) * num_buckets_));
 334
 335   int bucket_count = 0;
 336   for (int i = 0; i < kHashTableSize; i++) {
 337     for (Bucket* curr = bucket_table_[i]; curr != 0; curr = curr->next) {
 338       list[bucket_count++] = curr;
 339     }
 340   }
 341   RAW_DCHECK(bucket_count == num_buckets_, "");
 342
 343   sort(list, list + num_buckets_, ByAllocatedSpace);
 344
 345   return list;
 346 }
 347
 348 void HeapProfileTable::DumpMarkedObjects(AllocationMark mark,
 349                                          const char* file_name) {
 350   RawFD fd = RawOpenForWriting(file_name);
 351   if (fd == kIllegalRawFD) {
 352     RAW_LOG(ERROR, "Failed dumping live objects to %s", file_name);
 353     return;
 354   }
 355   const DumpMarkedArgs args(fd, mark);
 356   address_map_->Iterate<const DumpMarkedArgs&>(DumpMarkedIterator, args);
 357   RawClose(fd);
 358 }
 359
 360 #if defined(TYPE_PROFILING)
 361 void HeapProfileTable::DumpTypeStatistics(const char* file_name) const {
 362   RawFD fd = RawOpenForWriting(file_name);
 363   if (fd == kIllegalRawFD) {
 364     RAW_LOG(ERROR, "Failed dumping type statistics to %s", file_name);
 365     return;
 366   }
 367
 368   AddressMap<TypeCount>* type_size_map;
 369   type_size_map = new(alloc_(sizeof(AddressMap<TypeCount>)))
 370       AddressMap<TypeCount>(alloc_, dealloc_);
 371   address_map_->Iterate(TallyTypesItererator, type_size_map);
 372
 373   RawWrite(fd, kTypeProfileStatsHeader, strlen(kTypeProfileStatsHeader));
 374   const DumpArgs args(fd, NULL);
 375   type_size_map->Iterate<const DumpArgs&>(DumpTypesIterator, args);
 376   RawClose(fd);
 377
 378   type_size_map->~AddressMap<TypeCount>();
 379   dealloc_(type_size_map);
 380 }
 381 #endif  // defined(TYPE_PROFILING)
 382
 383 void HeapProfileTable::IterateOrderedAllocContexts(
 384     AllocContextIterator callback) const {
 385   Bucket** list = MakeSortedBucketList();
 386   AllocContextInfo info;
 387   for (int i = 0; i < num_buckets_; ++i) {
 388     *static_cast<Stats*>(&info) = *static_cast<Stats*>(list[i]);
 389     info.stack_depth = list[i]->depth;
 390     info.call_stack = list[i]->stack;
 391     callback(info);
 392   }
 393   dealloc_(list);
 394 }
 395
 396 int HeapProfileTable::FillOrderedProfile(char buf[], int size) const {
 397   Bucket** list = MakeSortedBucketList();
 398
 399   // Our file format is "bucket, bucket, ..., bucket, proc_self_maps_info".
 400   // In the cases buf is too small, we'd rather leave out the last
 401   // buckets than leave out the /proc/self/maps info.  To ensure that,
 402   // we actually print the /proc/self/maps info first, then move it to
 403   // the end of the buffer, then write the bucket info into whatever
 404   // is remaining, and then move the maps info one last time to close
 405   // any gaps.  Whew!
 406   int map_length = snprintf(buf, size, "%s", kProcSelfMapsHeader);
 407   if (map_length < 0 || map_length >= size) return 0;
 408   bool dummy;   // "wrote_all" -- did /proc/self/maps fit in its entirety?
 409   map_length += FillProcSelfMaps(buf + map_length, size - map_length, &dummy);
 410   RAW_DCHECK(map_length <= size, "");
 411   char* const map_start = buf + size - map_length;      // move to end
 412   memmove(map_start, buf, map_length);
 413   size -= map_length;
 414
 415   Stats stats;
 416   memset(&stats, 0, sizeof(stats));
 417   int bucket_length = snprintf(buf, size, "%s", kProfileHeader);
 418   if (bucket_length < 0 || bucket_length >= size) return 0;
 419   bucket_length = UnparseBucket(total_, buf, bucket_length, size,
 420                                 " heapprofile", &stats);
 421
 422   // Dump the mmap list first.
 423   if (profile_mmap_) {
 424     BufferArgs buffer(buf, bucket_length, size);
 425     MemoryRegionMap::IterateBuckets<BufferArgs*>(DumpBucketIterator, &buffer);
 426     bucket_length = buffer.buflen;
 427   }
 428
 429   for (int i = 0; i < num_buckets_; i++) {
 430     bucket_length = UnparseBucket(*list[i], buf, bucket_length, size, "",
 431                                   &stats);
 432   }
 433   RAW_DCHECK(bucket_length < size, "");
 434
 435   dealloc_(list);
 436
 437   RAW_DCHECK(buf + bucket_length <= map_start, "");
 438   memmove(buf + bucket_length, map_start, map_length);  // close the gap
 439
 440   return bucket_length + map_length;
 441 }
 442
 443 // static
 444 void HeapProfileTable::DumpBucketIterator(const Bucket* bucket,
 445                                           BufferArgs* args) {
 446   args->buflen = UnparseBucket(*bucket, args->buf, args->buflen, args->bufsize,
 447                                "", NULL);
 448 }
 449
 450 #if defined(TYPE_PROFILING)
 451 // static
 452 void HeapProfileTable::TallyTypesItererator(
 453     const void* ptr,
 454     AllocValue* value,
 455     AddressMap<TypeCount>* type_size_map) {
 456   const std::type_info* type = LookupType(ptr);
 457
 458   const void* key = NULL;
 459   if (type)
 460     key = type->name();
 461
 462   TypeCount* count = type_size_map->FindMutable(key);
 463   if (count) {
 464     count->bytes += value->bytes;
 465     ++count->objects;
 466   } else {
 467     type_size_map->Insert(key, TypeCount(value->bytes, 1));
 468   }
 469 }
 470
 471 // static
 472 void HeapProfileTable::DumpTypesIterator(const void* ptr,
 473                                          TypeCount* count,
 474                                          const DumpArgs& args) {
 475   char buf[1024];
 476   int len;
 477   const char* mangled_type_name = static_cast<const char*>(ptr);
 478   len = snprintf(buf, sizeof(buf), "%6d: %8"PRId64" @ %s\n",
 479                  count->objects, count->bytes,
 480                  mangled_type_name ? mangled_type_name : "(no_typeinfo)");
 481   RawWrite(args.fd, buf, len);
 482 }
 483 #endif  // defined(TYPE_PROFILING)
 484
 485 inline
 486 void HeapProfileTable::DumpNonLiveIterator(const void* ptr, AllocValue* v,
 487                                            const DumpArgs& args) {
 488   if (v->live()) {
 489     v->set_live(false);
 490     return;
 491   }
 492   if (v->ignore()) {
 493     return;
 494   }
 495   Bucket b;
 496   memset(&b, 0, sizeof(b));
 497   b.allocs = 1;
 498   b.alloc_size = v->bytes;
 499   b.depth = v->bucket()->depth;
 500   b.stack = v->bucket()->stack;
 501   char buf[1024];
 502   int len = UnparseBucket(b, buf, 0, sizeof(buf), "", args.profile_stats);
 503   RawWrite(args.fd, buf, len);
 504 }
 505
 506 inline
 507 void HeapProfileTable::DumpMarkedIterator(const void* ptr, AllocValue* v,
 508                                           const DumpMarkedArgs& args) {
 509   if (v->mark() != args.mark)
 510     return;
 511   Bucket b;
 512   memset(&b, 0, sizeof(b));
 513   b.allocs = 1;
 514   b.alloc_size = v->bytes;
 515   b.depth = v->bucket()->depth;
 516   b.stack = v->bucket()->stack;
 517   char addr[16];
 518   snprintf(addr, 16, "0x%08" PRIxPTR, ptr);
 519   char buf[1024];
 520   int len = UnparseBucket(b, buf, 0, sizeof(buf), addr, NULL);
 521   RawWrite(args.fd, buf, len);
 522 }
 523
 524 inline
 525 void HeapProfileTable::AllocationAddressesIterator(
 526     const void* ptr,
 527     AllocValue* v,
 528     const AllocationAddressIteratorArgs& args) {
 529   args.callback(args.data, ptr);
 530 }
 531
 532 inline
 533 void HeapProfileTable::MarkIterator(const void* ptr, AllocValue* v,
 534                                     const MarkArgs& args) {
 535   if (!args.mark_all && v->mark() != UNMARKED)
 536     return;
 537   v->set_mark(args.mark);
 538 }
 539
 540 // Callback from NonLiveSnapshot; adds entry to arg->dest
 541 // if not the entry is not live and is not present in arg->base.
 542 void HeapProfileTable::AddIfNonLive(const void* ptr, AllocValue* v,
 543                                     AddNonLiveArgs* arg) {
 544   if (v->live()) {
 545     v->set_live(false);
 546   } else {
 547     if (arg->base != NULL && arg->base->map_.Find(ptr) != NULL) {
 548       // Present in arg->base, so do not save
 549     } else {
 550       arg->dest->Add(ptr, *v);
 551     }
 552   }
 553 }
 554
 555 bool HeapProfileTable::WriteProfile(const char* file_name,
 556                                     const Bucket& total,
 557                                     AllocationMap* allocations) {
 558   RAW_VLOG(1, "Dumping non-live heap profile to %s", file_name);
 559   RawFD fd = RawOpenForWriting(file_name);
 560   if (fd == kIllegalRawFD) {
 561     RAW_LOG(ERROR, "Failed dumping filtered heap profile to %s", file_name);
 562     return false;
 563   }
 564   RawWrite(fd, kProfileHeader, strlen(kProfileHeader));
 565   char buf[512];
 566   int len = UnparseBucket(total, buf, 0, sizeof(buf), " heapprofile",
 567                           NULL);
 568   RawWrite(fd, buf, len);
 569   const DumpArgs args(fd, NULL);
 570   allocations->Iterate<const DumpArgs&>(DumpNonLiveIterator, args);
 571   RawWrite(fd, kProcSelfMapsHeader, strlen(kProcSelfMapsHeader));
 572   DumpProcSelfMaps(fd);
 573   RawClose(fd);
 574   return true;
 575 }
 576
 577 void HeapProfileTable::CleanupOldProfiles(const char* prefix) {
 578   if (!FLAGS_cleanup_old_heap_profiles)
 579     return;
 580   char buf[1000];
 581   snprintf(buf, 1000,"%s.%05d.", prefix, getpid());
 582   string pattern = string(buf) + ".*" + kFileExt;
 583
 584 #if defined(HAVE_GLOB_H)
 585   glob_t g;
 586   const int r = glob(pattern.c_str(), GLOB_ERR, NULL, &g);
 587   if (r == 0 || r == GLOB_NOMATCH) {
 588     const int prefix_length = strlen(prefix);
 589     for (int i = 0; i < g.gl_pathc; i++) {
 590       const char* fname = g.gl_pathv[i];
 591       if ((strlen(fname) >= prefix_length) &&
 592           (memcmp(fname, prefix, prefix_length) == 0)) {
 593         RAW_VLOG(1, "Removing old heap profile %s", fname);
 594         unlink(fname);
 595       }
 596     }
 597   }
 598   globfree(&g);
 599 #else   /* HAVE_GLOB_H */
 600   RAW_LOG(WARNING, "Unable to remove old heap profiles (can't run glob())");
 601 #endif
 602 }
 603
 604 HeapProfileTable::Snapshot* HeapProfileTable::TakeSnapshot() {
 605   Snapshot* s = new (alloc_(sizeof(Snapshot))) Snapshot(alloc_, dealloc_);
 606   address_map_->Iterate(AddToSnapshot, s);
 607   return s;
 608 }
 609
 610 void HeapProfileTable::ReleaseSnapshot(Snapshot* s) {
 611   s->~Snapshot();
 612   dealloc_(s);
 613 }
 614
 615 // Callback from TakeSnapshot; adds a single entry to snapshot
 616 void HeapProfileTable::AddToSnapshot(const void* ptr, AllocValue* v,
 617                                      Snapshot* snapshot) {
 618   snapshot->Add(ptr, *v);
 619 }
 620
 621 HeapProfileTable::Snapshot* HeapProfileTable::NonLiveSnapshot(
 622     Snapshot* base) {
 623   RAW_VLOG(2, "NonLiveSnapshot input: %d %d\n",
 624            int(total_.allocs - total_.frees),
 625            int(total_.alloc_size - total_.free_size));
 626
 627   Snapshot* s = new (alloc_(sizeof(Snapshot))) Snapshot(alloc_, dealloc_);
 628   AddNonLiveArgs args;
 629   args.dest = s;
 630   args.base = base;
 631   address_map_->Iterate<AddNonLiveArgs*>(AddIfNonLive, &args);
 632   RAW_VLOG(2, "NonLiveSnapshot output: %d %d\n",
 633            int(s->total_.allocs - s->total_.frees),
 634            int(s->total_.alloc_size - s->total_.free_size));
 635   return s;
 636 }
 637
 638 // Information kept per unique bucket seen
 639 struct HeapProfileTable::Snapshot::Entry {
 640   int count;
 641   int bytes;
 642   Bucket* bucket;
 643   Entry() : count(0), bytes(0) { }
 644
 645   // Order by decreasing bytes
 646   bool operator<(const Entry& x) const {
 647     return this->bytes > x.bytes;
 648   }
 649 };
 650
 651 // State used to generate leak report.  We keep a mapping from Bucket pointer
 652 // the collected stats for that bucket.
 653 struct HeapProfileTable::Snapshot::ReportState {
 654   map<Bucket*, Entry> buckets_;
 655 };
 656
 657 // Callback from ReportLeaks; updates ReportState.
 658 void HeapProfileTable::Snapshot::ReportCallback(const void* ptr,
 659                                                 AllocValue* v,
 660                                                 ReportState* state) {
 661   Entry* e = &state->buckets_[v->bucket()]; // Creates empty Entry first time
 662   e->bucket = v->bucket();
 663   e->count++;
 664   e->bytes += v->bytes;
 665 }
 666
 667 void HeapProfileTable::Snapshot::ReportLeaks(const char* checker_name,
 668                                              const char* filename,
 669                                              bool should_symbolize) {
 670   // This is only used by the heap leak checker, but is intimately
 671   // tied to the allocation map that belongs in this module and is
 672   // therefore placed here.
 673   RAW_LOG(ERROR, "Leak check %s detected leaks of %"PRIuS" bytes "
 674           "in %"PRIuS" objects",
 675           checker_name,
 676           size_t(total_.alloc_size),
 677           size_t(total_.allocs));
 678
 679   // Group objects by Bucket
 680   ReportState state;
 681   map_.Iterate(&ReportCallback, &state);
 682
 683   // Sort buckets by decreasing leaked size
 684   const int n = state.buckets_.size();
 685   Entry* entries = new Entry[n];
 686   int dst = 0;
 687   for (map<Bucket*,Entry>::const_iterator iter = state.buckets_.begin();
 688        iter != state.buckets_.end();
 689        ++iter) {
 690     entries[dst++] = iter->second;
 691   }
 692   sort(entries, entries + n);
 693
 694   // Report a bounded number of leaks to keep the leak report from
 695   // growing too long.
 696   const int to_report =
 697       (FLAGS_heap_check_max_leaks > 0 &&
 698        n > FLAGS_heap_check_max_leaks) ? FLAGS_heap_check_max_leaks : n;
 699   RAW_LOG(ERROR, "The %d largest leaks:", to_report);
 700
 701   // Print
 702   SymbolTable symbolization_table;
 703   for (int i = 0; i < to_report; i++) {
 704     const Entry& e = entries[i];
 705     for (int j = 0; j < e.bucket->depth; j++) {
 706       symbolization_table.Add(e.bucket->stack[j]);
 707     }
 708   }
 709   static const int kBufSize = 2<<10;
 710   char buffer[kBufSize];
 711   if (should_symbolize)
 712     symbolization_table.Symbolize();
 713   for (int i = 0; i < to_report; i++) {
 714     const Entry& e = entries[i];
 715     base::RawPrinter printer(buffer, kBufSize);
 716     printer.Printf("Leak of %d bytes in %d objects allocated from:\n",
 717                    e.bytes, e.count);
 718     for (int j = 0; j < e.bucket->depth; j++) {
 719       const void* pc = e.bucket->stack[j];
 720       printer.Printf("\t@ %"PRIxPTR" %s\n",
 721           reinterpret_cast<uintptr_t>(pc), symbolization_table.GetSymbol(pc));
 722     }
 723     RAW_LOG(ERROR, "%s", buffer);
 724   }
 725
 726   if (to_report < n) {
 727     RAW_LOG(ERROR, "Skipping leaks numbered %d..%d",
 728             to_report, n-1);
 729   }
 730   delete[] entries;
 731
 732   // TODO: Dump the sorted Entry list instead of dumping raw data?
 733   // (should be much shorter)
 734   if (!HeapProfileTable::WriteProfile(filename, total_, &map_)) {
 735     RAW_LOG(ERROR, "Could not write pprof profile to %s", filename);
 736   }
 737 }
 738
 739 void HeapProfileTable::Snapshot::ReportObject(const void* ptr,
 740                                               AllocValue* v,
 741                                               char* unused) {
 742   // Perhaps also log the allocation stack trace (unsymbolized)
 743   // on this line in case somebody finds it useful.
 744   RAW_LOG(ERROR, "leaked %"PRIuS" byte object %p", v->bytes, ptr);
 745 }
 746
 747 void HeapProfileTable::Snapshot::ReportIndividualObjects() {
 748   char unused;
 749   map_.Iterate(ReportObject, &unused);
 750 }