third_party/tcmalloc/chromium/src/heap-profiler.cc

/* [<][>][^][v][top][bottom][index][help] */
This source file includes following definitions.
ProfilerMalloc
ProfilerFree
DoGetHeapProfileLocked
GetHeapProfile
DumpProfileLocked
MaybeDumpProfileLocked
RecordAlloc
RecordFree
NewHook
DeleteHook
RawInfoStackDumper
MmapHook
MremapHook
MunmapHook
SbrkHook
HeapProfilerStart
HeapProfilerWithPseudoStackStart
IterateAllocatedObjects
IsHeapProfilerRunning
HeapProfilerStop
HeapProfilerDump
HeapProfilerMarkBaseline
HeapProfilerMarkInteresting
HeapProfilerDumpAliveObjects
HeapProfilerInit
// Copyright (c) 2005, Google Inc.
// All rights reserved.
// 
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
// 
//     * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
//     * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
// 
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

// ---
// Author: Sanjay Ghemawat
//
// TODO: Log large allocations

#include <config.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#ifdef HAVE_INTTYPES_H
#include <inttypes.h>
#endif
#ifdef HAVE_FCNTL_H
#include <fcntl.h>    // for open()
#endif
#ifdef HAVE_MMAP
#include <sys/mman.h>
#endif
#include <errno.h>
#include <assert.h>
#include <sys/types.h>

#include <algorithm>
#include <string>

#include <gperftools/heap-profiler.h>

#include "base/logging.h"
#include "base/basictypes.h"   // for PRId64, among other things
#include "base/googleinit.h"
#include "base/commandlineflags.h"
#include "malloc_hook-inl.h"
#include "tcmalloc_guard.h"
#include <gperftools/malloc_hook.h>
#include <gperftools/malloc_extension.h>
#include "base/spinlock.h"
#include "base/low_level_alloc.h"
#include "base/sysinfo.h"      // for GetUniquePathFromEnv()
#include "deep-heap-profile.h"
#include "heap-profile-table.h"
#include "memory_region_map.h"


#ifndef PATH_MAX
#ifdef MAXPATHLEN
#define PATH_MAX        MAXPATHLEN
#else
#define PATH_MAX        4096         // seems conservative for max filename len!
#endif
#endif

#if defined(__ANDROID__) || defined(ANDROID)
// On android, there are no environment variables.
// Instead, we use system properties, set via:
//   adb shell setprop prop_name prop_value
// From <sys/system_properties.h>,
//   PROP_NAME_MAX   32
//   PROP_VALUE_MAX  92
#define HEAPPROFILE "heapprof"
#define HEAP_PROFILE_ALLOCATION_INTERVAL "heapprof.allocation_interval"
#define HEAP_PROFILE_DEALLOCATION_INTERVAL "heapprof.deallocation_interval"
#define HEAP_PROFILE_INUSE_INTERVAL "heapprof.inuse_interval"
#define HEAP_PROFILE_TIME_INTERVAL "heapprof.time_interval"
#define HEAP_PROFILE_MMAP_LOG "heapprof.mmap_log"
#define HEAP_PROFILE_MMAP "heapprof.mmap"
#define HEAP_PROFILE_ONLY_MMAP "heapprof.only_mmap"
#define DEEP_HEAP_PROFILE "heapprof.deep_heap_profile"
#define DEEP_HEAP_PROFILE_PAGEFRAME "heapprof.deep.pageframe"
#define HEAP_PROFILE_TYPE_STATISTICS "heapprof.type_statistics"
#else  // defined(__ANDROID__) || defined(ANDROID)
#define HEAPPROFILE "HEAPPROFILE"
#define HEAP_PROFILE_ALLOCATION_INTERVAL "HEAP_PROFILE_ALLOCATION_INTERVAL"
#define HEAP_PROFILE_DEALLOCATION_INTERVAL "HEAP_PROFILE_DEALLOCATION_INTERVAL"
#define HEAP_PROFILE_INUSE_INTERVAL "HEAP_PROFILE_INUSE_INTERVAL"
#define HEAP_PROFILE_TIME_INTERVAL "HEAP_PROFILE_TIME_INTERVAL"
#define HEAP_PROFILE_MMAP_LOG "HEAP_PROFILE_MMAP_LOG"
#define HEAP_PROFILE_MMAP "HEAP_PROFILE_MMAP"
#define HEAP_PROFILE_ONLY_MMAP "HEAP_PROFILE_ONLY_MMAP"
#define DEEP_HEAP_PROFILE "DEEP_HEAP_PROFILE"
#define DEEP_HEAP_PROFILE_PAGEFRAME "DEEP_HEAP_PROFILE_PAGEFRAME"
#define HEAP_PROFILE_TYPE_STATISTICS "HEAP_PROFILE_TYPE_STATISTICS"
#endif  // defined(__ANDROID__) || defined(ANDROID)

using STL_NAMESPACE::string;
using STL_NAMESPACE::sort;

//----------------------------------------------------------------------
// Flags that control heap-profiling
//
// The thread-safety of the profiler depends on these being immutable
// after main starts, so don't change them.
//----------------------------------------------------------------------

DEFINE_int64(heap_profile_allocation_interval,
             EnvToInt64(HEAP_PROFILE_ALLOCATION_INTERVAL, 1 << 30 /*1GB*/),
             "If non-zero, dump heap profiling information once every "
             "specified number of bytes allocated by the program since "
             "the last dump.");
DEFINE_int64(heap_profile_deallocation_interval,
             EnvToInt64(HEAP_PROFILE_DEALLOCATION_INTERVAL, 0),
             "If non-zero, dump heap profiling information once every "
             "specified number of bytes deallocated by the program "
             "since the last dump.");
// We could also add flags that report whenever inuse_bytes changes by
// X or -X, but there hasn't been a need for that yet, so we haven't.
DEFINE_int64(heap_profile_inuse_interval,
             EnvToInt64(HEAP_PROFILE_INUSE_INTERVAL, 100 << 20 /*100MB*/),
             "If non-zero, dump heap profiling information whenever "
             "the high-water memory usage mark increases by the specified "
             "number of bytes.");
DEFINE_int64(heap_profile_time_interval,
             EnvToInt64(HEAP_PROFILE_TIME_INTERVAL, 0),
             "If non-zero, dump heap profiling information once every "
             "specified number of seconds since the last dump.");
DEFINE_bool(mmap_log,
            EnvToBool(HEAP_PROFILE_MMAP_LOG, false),
            "Should mmap/munmap calls be logged?");
DEFINE_bool(mmap_profile,
            EnvToBool(HEAP_PROFILE_MMAP, false),
            "If heap-profiling is on, also profile mmap, mremap, and sbrk)");
DEFINE_bool(only_mmap_profile,
            EnvToBool(HEAP_PROFILE_ONLY_MMAP, false),
            "If heap-profiling is on, only profile mmap, mremap, and sbrk; "
            "do not profile malloc/new/etc");
DEFINE_bool(deep_heap_profile,
            EnvToBool(DEEP_HEAP_PROFILE, false),
            "If heap-profiling is on, profile deeper (Linux and Android)");
DEFINE_int32(deep_heap_profile_pageframe,
             EnvToInt(DEEP_HEAP_PROFILE_PAGEFRAME, 0),
             "Needs deeper profile. If 1, dump page frame numbers (PFNs). "
             "If 2, dump page counts (/proc/kpagecount) with PFNs.");
#if defined(TYPE_PROFILING)
DEFINE_bool(heap_profile_type_statistics,
            EnvToBool(HEAP_PROFILE_TYPE_STATISTICS, false),
            "If heap-profiling is on, dump type statistics.");
#endif  // defined(TYPE_PROFILING)


//----------------------------------------------------------------------
// Locking
//----------------------------------------------------------------------

// A pthread_mutex has way too much lock contention to be used here.
//
// I would like to use Mutex, but it can call malloc(),
// which can cause us to fall into an infinite recursion.
//
// So we use a simple spinlock.
static SpinLock heap_lock(SpinLock::LINKER_INITIALIZED);

//----------------------------------------------------------------------
// Simple allocator for heap profiler's internal memory
//----------------------------------------------------------------------

static LowLevelAlloc::Arena *heap_profiler_memory;

static void* ProfilerMalloc(size_t bytes) {
  return LowLevelAlloc::AllocWithArena(bytes, heap_profiler_memory);
}
static void ProfilerFree(void* p) {
  LowLevelAlloc::Free(p);
}

// We use buffers of this size in DoGetHeapProfile.
static const int kProfileBufferSize = 1 << 20;

// This is a last-ditch buffer we use in DumpProfileLocked in case we
// can't allocate more memory from ProfilerMalloc.  We expect this
// will be used by HeapProfileEndWriter when the application has to
// exit due to out-of-memory.  This buffer is allocated in
// HeapProfilerStart.  Access to this must be protected by heap_lock.
static char* global_profiler_buffer = NULL;


//----------------------------------------------------------------------
// Profiling control/state data
//----------------------------------------------------------------------

// Access to all of these is protected by heap_lock.
static bool  is_on = false;           // If are on as a subsytem.
static bool  dumping = false;         // Dumping status to prevent recursion
static char* filename_prefix = NULL;  // Prefix used for profile file names
                                      // (NULL if no need for dumping yet)
static int   dump_count = 0;          // How many dumps so far
static int64 last_dump_alloc = 0;     // alloc_size when did we last dump
static int64 last_dump_free = 0;      // free_size when did we last dump
static int64 high_water_mark = 0;     // In-use-bytes at last high-water dump
static int64 last_dump_time = 0;      // The time of the last dump

static HeapProfileTable* heap_profile = NULL;  // the heap profile table
static DeepHeapProfile* deep_profile = NULL;  // deep memory profiler

// Callback to generate a stack trace for an allocation. May be overriden
// by an application to provide its own pseudo-stacks.
static StackGeneratorFunction stack_generator_function =
    HeapProfileTable::GetCallerStackTrace;

//----------------------------------------------------------------------
// Profile generation
//----------------------------------------------------------------------

// Input must be a buffer of size at least 1MB.
static char* DoGetHeapProfileLocked(char* buf, int buflen) {
  // We used to be smarter about estimating the required memory and
  // then capping it to 1MB and generating the profile into that.
  if (buf == NULL || buflen < 1)
    return NULL;

  RAW_DCHECK(heap_lock.IsHeld(), "");
  int bytes_written = 0;
  if (is_on) {
    HeapProfileTable::Stats const stats = heap_profile->total();
    (void)stats;   // avoid an unused-variable warning in non-debug mode.
    bytes_written = heap_profile->FillOrderedProfile(buf, buflen - 1);
    // FillOrderedProfile should not reduce the set of active mmap-ed regions,
    // hence MemoryRegionMap will let us remove everything we've added above:
    RAW_DCHECK(stats.Equivalent(heap_profile->total()), "");
    // if this fails, we somehow removed by FillOrderedProfile
    // more than we have added.
  }
  buf[bytes_written] = '\0';
  RAW_DCHECK(bytes_written == strlen(buf), "");

  return buf;
}

extern "C" char* GetHeapProfile() {
  // Use normal malloc: we return the profile to the user to free it:
  char* buffer = reinterpret_cast<char*>(malloc(kProfileBufferSize));
  SpinLockHolder l(&heap_lock);
  return DoGetHeapProfileLocked(buffer, kProfileBufferSize);
}

// defined below
static void NewHook(const void* ptr, size_t size);
static void DeleteHook(const void* ptr);

// Helper for HeapProfilerDump.
static void DumpProfileLocked(const char* reason) {
  RAW_DCHECK(heap_lock.IsHeld(), "");
  RAW_DCHECK(is_on, "");
  RAW_DCHECK(!dumping, "");

  if (filename_prefix == NULL) return;  // we do not yet need dumping

  dumping = true;

  // Make file name
  char file_name[1000];
  dump_count++;
  snprintf(file_name, sizeof(file_name), "%s.%05d.%04d%s",
           filename_prefix, getpid(), dump_count, HeapProfileTable::kFileExt);

  // Dump the profile
  RAW_VLOG(0, "Dumping heap profile to %s (%s)", file_name, reason);
  // We must use file routines that don't access memory, since we hold
  // a memory lock now.
  RawFD fd = RawOpenForWriting(file_name);
  if (fd == kIllegalRawFD) {
    RAW_LOG(ERROR, "Failed dumping heap profile to %s", file_name);
    dumping = false;
    return;
  }

  // This case may be impossible, but it's best to be safe.
  // It's safe to use the global buffer: we're protected by heap_lock.
  if (global_profiler_buffer == NULL) {
    global_profiler_buffer =
        reinterpret_cast<char*>(ProfilerMalloc(kProfileBufferSize));
  }

  if (deep_profile) {
    deep_profile->DumpOrderedProfile(reason, global_profiler_buffer,
                                     kProfileBufferSize, fd);
  } else {
    char* profile = DoGetHeapProfileLocked(global_profiler_buffer,
                                           kProfileBufferSize);
    RawWrite(fd, profile, strlen(profile));
  }
  RawClose(fd);

#if defined(TYPE_PROFILING)
  if (FLAGS_heap_profile_type_statistics) {
    snprintf(file_name, sizeof(file_name), "%s.%05d.%04d.type",
             filename_prefix, getpid(), dump_count);
    RAW_VLOG(0, "Dumping type statistics to %s", file_name);
    heap_profile->DumpTypeStatistics(file_name);
  }
#endif  // defined(TYPE_PROFILING)

  dumping = false;
}

//----------------------------------------------------------------------
// Profile collection
//----------------------------------------------------------------------

// Dump a profile after either an allocation or deallocation, if
// the memory use has changed enough since the last dump.
static void MaybeDumpProfileLocked() {
  if (!dumping) {
    const HeapProfileTable::Stats& total = heap_profile->total();
    const int64 inuse_bytes = total.alloc_size - total.free_size;
    bool need_to_dump = false;
    char buf[128];
    int64 current_time = time(NULL);
    if (FLAGS_heap_profile_allocation_interval > 0 &&
        total.alloc_size >=
        last_dump_alloc + FLAGS_heap_profile_allocation_interval) {
      snprintf(buf, sizeof(buf), ("%" PRId64 " MB allocated cumulatively, "
                                  "%" PRId64 " MB currently in use"),
               total.alloc_size >> 20, inuse_bytes >> 20);
      need_to_dump = true;
    } else if (FLAGS_heap_profile_deallocation_interval > 0 &&
               total.free_size >=
               last_dump_free + FLAGS_heap_profile_deallocation_interval) {
      snprintf(buf, sizeof(buf), ("%" PRId64 " MB freed cumulatively, "
                                  "%" PRId64 " MB currently in use"),
               total.free_size >> 20, inuse_bytes >> 20);
      need_to_dump = true;
    } else if (FLAGS_heap_profile_inuse_interval > 0 &&
               inuse_bytes >
               high_water_mark + FLAGS_heap_profile_inuse_interval) {
      snprintf(buf, sizeof(buf), "%" PRId64 " MB currently in use",
               inuse_bytes >> 20);
      need_to_dump = true;
    } else if (FLAGS_heap_profile_time_interval > 0 &&
               current_time - last_dump_time >=
               FLAGS_heap_profile_time_interval) {
      snprintf(buf, sizeof(buf), "%" PRId64 " sec since the last dump",
               current_time - last_dump_time);
      need_to_dump = true;
      last_dump_time = current_time;
    }
    if (need_to_dump) {
      DumpProfileLocked(buf);

      last_dump_alloc = total.alloc_size;
      last_dump_free = total.free_size;
      if (inuse_bytes > high_water_mark)
        high_water_mark = inuse_bytes;
    }
  }
}

// Record an allocation in the profile.
static void RecordAlloc(const void* ptr, size_t bytes, int skip_count) {
  // Take the stack trace outside the critical section.
  void* stack[HeapProfileTable::kMaxStackDepth];
  int depth = stack_generator_function(skip_count + 1, stack);
  SpinLockHolder l(&heap_lock);
  if (is_on) {
    heap_profile->RecordAlloc(ptr, bytes, depth, stack);
    MaybeDumpProfileLocked();
  }
}

// Record a deallocation in the profile.
static void RecordFree(const void* ptr) {
  SpinLockHolder l(&heap_lock);
  if (is_on) {
    heap_profile->RecordFree(ptr);
    MaybeDumpProfileLocked();
  }
}

//----------------------------------------------------------------------
// Allocation/deallocation hooks for MallocHook
//----------------------------------------------------------------------

// static
void NewHook(const void* ptr, size_t size) {
  if (ptr != NULL) RecordAlloc(ptr, size, 0);
}

// static
void DeleteHook(const void* ptr) {
  if (ptr != NULL) RecordFree(ptr);
}

// TODO(jandrews): Re-enable stack tracing
#ifdef TODO_REENABLE_STACK_TRACING
static void RawInfoStackDumper(const char* message, void*) {
  RAW_LOG(INFO, "%.*s", static_cast<int>(strlen(message) - 1), message);
  // -1 is to chop the \n which will be added by RAW_LOG
}
#endif

static void MmapHook(const void* result, const void* start, size_t size,
                     int prot, int flags, int fd, off_t offset) {
  if (FLAGS_mmap_log) {  // log it
    // We use PRIxS not just '%p' to avoid deadlocks
    // in pretty-printing of NULL as "nil".
    // TODO(maxim): instead should use a safe snprintf reimplementation
    RAW_LOG(INFO,
            "mmap(start=0x%" PRIxPTR ", len=%" PRIuS ", prot=0x%x, flags=0x%x, "
            "fd=%d, offset=0x%x) = 0x%" PRIxPTR,
            (uintptr_t) start, size, prot, flags, fd, (unsigned int) offset,
            (uintptr_t) result);
#ifdef TODO_REENABLE_STACK_TRACING
    DumpStackTrace(1, RawInfoStackDumper, NULL);
#endif
  }
}

static void MremapHook(const void* result, const void* old_addr,
                       size_t old_size, size_t new_size,
                       int flags, const void* new_addr) {
  if (FLAGS_mmap_log) {  // log it
    // We use PRIxS not just '%p' to avoid deadlocks
    // in pretty-printing of NULL as "nil".
    // TODO(maxim): instead should use a safe snprintf reimplementation
    RAW_LOG(INFO,
            "mremap(old_addr=0x%" PRIxPTR ", old_size=%" PRIuS ", "
            "new_size=%" PRIuS ", flags=0x%x, new_addr=0x%" PRIxPTR ") = "
            "0x%" PRIxPTR,
            (uintptr_t) old_addr, old_size, new_size, flags,
            (uintptr_t) new_addr, (uintptr_t) result);
#ifdef TODO_REENABLE_STACK_TRACING
    DumpStackTrace(1, RawInfoStackDumper, NULL);
#endif
  }
}

static void MunmapHook(const void* ptr, size_t size) {
  if (FLAGS_mmap_log) {  // log it
    // We use PRIxS not just '%p' to avoid deadlocks
    // in pretty-printing of NULL as "nil".
    // TODO(maxim): instead should use a safe snprintf reimplementation
    RAW_LOG(INFO, "munmap(start=0x%" PRIxPTR ", len=%" PRIuS ")",
                  (uintptr_t) ptr, size);
#ifdef TODO_REENABLE_STACK_TRACING
    DumpStackTrace(1, RawInfoStackDumper, NULL);
#endif
  }
}

static void SbrkHook(const void* result, ptrdiff_t increment) {
  if (FLAGS_mmap_log) {  // log it
    RAW_LOG(INFO, "sbrk(inc=%" PRIdS ") = 0x%" PRIxPTR,
                  increment, (uintptr_t) result);
#ifdef TODO_REENABLE_STACK_TRACING
    DumpStackTrace(1, RawInfoStackDumper, NULL);
#endif
  }
}

//----------------------------------------------------------------------
// Starting/stopping/dumping
//----------------------------------------------------------------------

extern "C" void HeapProfilerStart(const char* prefix) {
  SpinLockHolder l(&heap_lock);

  if (is_on) return;

  is_on = true;

  RAW_VLOG(0, "Starting tracking the heap");

  // This should be done before the hooks are set up, since it should
  // call new, and we want that to be accounted for correctly.
  MallocExtension::Initialize();

  if (FLAGS_only_mmap_profile) {
    FLAGS_mmap_profile = true;
  }

  if (FLAGS_mmap_profile) {
    // Ask MemoryRegionMap to record all mmap, mremap, and sbrk
    // call stack traces of at least size kMaxStackDepth:
    MemoryRegionMap::Init(HeapProfileTable::kMaxStackDepth,
                          /* use_buckets */ true);
  }

  if (FLAGS_mmap_log) {
    // Install our hooks to do the logging:
    RAW_CHECK(MallocHook::AddMmapHook(&MmapHook), "");
    RAW_CHECK(MallocHook::AddMremapHook(&MremapHook), "");
    RAW_CHECK(MallocHook::AddMunmapHook(&MunmapHook), "");
    RAW_CHECK(MallocHook::AddSbrkHook(&SbrkHook), "");
  }

  heap_profiler_memory =
    LowLevelAlloc::NewArena(0, LowLevelAlloc::DefaultArena());

  // Reserve space now for the heap profiler, so we can still write a
  // heap profile even if the application runs out of memory.
  global_profiler_buffer =
      reinterpret_cast<char*>(ProfilerMalloc(kProfileBufferSize));

  heap_profile = new(ProfilerMalloc(sizeof(HeapProfileTable)))
      HeapProfileTable(ProfilerMalloc, ProfilerFree, FLAGS_mmap_profile);

  last_dump_alloc = 0;
  last_dump_free = 0;
  high_water_mark = 0;
  last_dump_time = 0;

  if (FLAGS_deep_heap_profile) {
    // Initialize deep memory profiler
    RAW_VLOG(0, "[%d] Starting a deep memory profiler", getpid());
    deep_profile = new(ProfilerMalloc(sizeof(DeepHeapProfile)))
        DeepHeapProfile(heap_profile, prefix, DeepHeapProfile::PageFrameType(
            FLAGS_deep_heap_profile_pageframe));
  }

  // We do not reset dump_count so if the user does a sequence of
  // HeapProfilerStart/HeapProfileStop, we will get a continuous
  // sequence of profiles.

  if (FLAGS_only_mmap_profile == false) {
    // Now set the hooks that capture new/delete and malloc/free.
    RAW_CHECK(MallocHook::AddNewHook(&NewHook), "");
    RAW_CHECK(MallocHook::AddDeleteHook(&DeleteHook), "");
  }

  // Copy filename prefix only if provided.
  if (!prefix)
    return;
  RAW_DCHECK(filename_prefix == NULL, "");
  const int prefix_length = strlen(prefix);
  filename_prefix = reinterpret_cast<char*>(ProfilerMalloc(prefix_length + 1));
  memcpy(filename_prefix, prefix, prefix_length);
  filename_prefix[prefix_length] = '\0';
}

extern "C" void HeapProfilerWithPseudoStackStart(
    StackGeneratorFunction callback) {
  {
    // Ensure the callback is set before allocations can be recorded.
    SpinLockHolder l(&heap_lock);
    stack_generator_function = callback;
  }
  HeapProfilerStart(NULL);
}

extern "C" void IterateAllocatedObjects(AddressVisitor visitor, void* data) {
  SpinLockHolder l(&heap_lock);

  if (!is_on) return;

  heap_profile->IterateAllocationAddresses(visitor, data);
}

extern "C" int IsHeapProfilerRunning() {
  SpinLockHolder l(&heap_lock);
  return is_on ? 1 : 0;   // return an int, because C code doesn't have bool
}

extern "C" void HeapProfilerStop() {
  SpinLockHolder l(&heap_lock);

  if (!is_on) return;

  if (FLAGS_only_mmap_profile == false) {
    // Unset our new/delete hooks, checking they were set:
    RAW_CHECK(MallocHook::RemoveNewHook(&NewHook), "");
    RAW_CHECK(MallocHook::RemoveDeleteHook(&DeleteHook), "");
  }
  if (FLAGS_mmap_log) {
    // Restore mmap/sbrk hooks, checking that our hooks were set:
    RAW_CHECK(MallocHook::RemoveMmapHook(&MmapHook), "");
    RAW_CHECK(MallocHook::RemoveMremapHook(&MremapHook), "");
    RAW_CHECK(MallocHook::RemoveSbrkHook(&SbrkHook), "");
    RAW_CHECK(MallocHook::RemoveMunmapHook(&MunmapHook), "");
  }

  if (deep_profile) {
    // free deep memory profiler
    deep_profile->~DeepHeapProfile();
    ProfilerFree(deep_profile);
    deep_profile = NULL;
  }

  // free profile
  heap_profile->~HeapProfileTable();
  ProfilerFree(heap_profile);
  heap_profile = NULL;

  // free output-buffer memory
  ProfilerFree(global_profiler_buffer);

  // free prefix
  ProfilerFree(filename_prefix);
  filename_prefix = NULL;

  if (!LowLevelAlloc::DeleteArena(heap_profiler_memory)) {
    RAW_LOG(FATAL, "Memory leak in HeapProfiler:");
  }

  if (FLAGS_mmap_profile) {
    MemoryRegionMap::Shutdown();
  }

  is_on = false;
}

extern "C" void HeapProfilerDump(const char* reason) {
  SpinLockHolder l(&heap_lock);
  if (is_on && !dumping) {
    DumpProfileLocked(reason);
  }
}

extern "C" void HeapProfilerMarkBaseline() {
  SpinLockHolder l(&heap_lock);

  if (!is_on) return;

  heap_profile->MarkCurrentAllocations(HeapProfileTable::MARK_ONE);
}

extern "C" void HeapProfilerMarkInteresting() {
  SpinLockHolder l(&heap_lock);

  if (!is_on) return;

  heap_profile->MarkUnmarkedAllocations(HeapProfileTable::MARK_TWO);
}

extern "C" void HeapProfilerDumpAliveObjects(const char* filename) {
  SpinLockHolder l(&heap_lock);

  if (!is_on) return;

  heap_profile->DumpMarkedObjects(HeapProfileTable::MARK_TWO, filename);
}

//----------------------------------------------------------------------
// Initialization/finalization code
//----------------------------------------------------------------------

// Initialization code
static void HeapProfilerInit() {
  // Everything after this point is for setting up the profiler based on envvar
  char fname[PATH_MAX];
  if (!GetUniquePathFromEnv(HEAPPROFILE, fname)) {
    return;
  }
  // We do a uid check so we don't write out files in a setuid executable.
#ifdef HAVE_GETEUID
  if (getuid() != geteuid()) {
    RAW_LOG(WARNING, ("HeapProfiler: ignoring " HEAPPROFILE " because "
                      "program seems to be setuid\n"));
    return;
  }
#endif

  HeapProfileTable::CleanupOldProfiles(fname);

  HeapProfilerStart(fname);
}

// class used for finalization -- dumps the heap-profile at program exit
struct HeapProfileEndWriter {
  ~HeapProfileEndWriter() { HeapProfilerDump("Exiting"); }
};

// We want to make sure tcmalloc is up and running before starting the profiler
static const TCMallocGuard tcmalloc_initializer;
REGISTER_MODULE_INITIALIZER(heapprofiler, HeapProfilerInit());
static HeapProfileEndWriter heap_profile_end_writer;
/* [<][>][^][v][top][bottom][index][help] */
root/third_party/tcmalloc/chromium/src/heap-profiler.cc

DEFINITIONS
