root/third_party/tcmalloc/chromium/src/malloc_extension.cc

DEFINITIONS

1. DumpAddressMap
2. Initialize
3. VerifyAllMemory
4. VerifyNewMemory
5. VerifyArrayNewMemory
6. VerifyMallocMemory
7. GetNumericProperty
8. SetNumericProperty
9. GetStats
10. MallocMemoryStats
11. ReadStackTraces
12. ReadHeapGrowthStackTraces
13. MarkThreadIdle
14. MarkThreadBusy
15. GetSystemAllocator
16. SetSystemAllocator
17. ReleaseToSystem
18. ReleaseFreeMemory
19. SetMemoryReleaseRate
20. GetMemoryReleaseRate
21. GetEstimatedAllocatedSize
22. GetAllocatedSize
23. GetOwnership
24. GetFreeListSizes
25. InitModule
26. instance
27. Register
28. GetBytesAllocatedOnCurrentThread
29. Count
30. Size
31. Depth
32. PC
33. PrintCountAndSize
34. PrintHeader
35. PrintStackEntry
36. GetHeapSample
37. GetHeapGrowthStacks
38. Ranges
39. MallocExtension_GetOwnership

// Copyright (c) 2012, 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 <opensource@google.com>

#include <config.h>
#include <assert.h>
#include <string.h>
#include <stdio.h>
#if defined HAVE_STDINT_H
#include <stdint.h>
#elif defined HAVE_INTTYPES_H
#include <inttypes.h>
#else
#include <sys/types.h>
#endif
#include <string>
#include "base/dynamic_annotations.h"
#include "base/sysinfo.h"    // for FillProcSelfMaps
#ifndef NO_HEAP_CHECK
#include "gperftools/heap-checker.h"
#endif
#include "gperftools/malloc_extension.h"
#include "gperftools/malloc_extension_c.h"
#include "maybe_threads.h"

#ifdef USE_TCMALLOC
// Note that malloc_extension can be used without tcmalloc if gperftools'
// heap-profiler is enabled without the tcmalloc memory allocator.
#include "thread_cache.h"
#endif

using STL_NAMESPACE::string;
using STL_NAMESPACE::vector;

static void DumpAddressMap(string* result) {
  *result += "\nMAPPED_LIBRARIES:\n";
  // We keep doubling until we get a fit
  const size_t old_resultlen = result->size();
  for (int amap_size = 10240; amap_size < 10000000; amap_size *= 2) {
    result->resize(old_resultlen + amap_size);
    bool wrote_all = false;
    const int bytes_written =
        tcmalloc::FillProcSelfMaps(&((*result)[old_resultlen]), amap_size,
                                   &wrote_all);
    if (wrote_all) {   // we fit!
      (*result)[old_resultlen + bytes_written] = '\0';
      result->resize(old_resultlen + bytes_written);
      return;
    }
  }
  result->reserve(old_resultlen);   // just don't print anything
}

// Note: this routine is meant to be called before threads are spawned.
void MallocExtension::Initialize() {
  static bool initialize_called = false;

  if (initialize_called) return;
  initialize_called = true;

#ifdef __GLIBC__
  // GNU libc++ versions 3.3 and 3.4 obey the environment variables
  // GLIBCPP_FORCE_NEW and GLIBCXX_FORCE_NEW respectively.  Setting
  // one of these variables forces the STL default allocator to call
  // new() or delete() for each allocation or deletion.  Otherwise
  // the STL allocator tries to avoid the high cost of doing
  // allocations by pooling memory internally.  However, tcmalloc
  // does allocations really fast, especially for the types of small
  // items one sees in STL, so it's better off just using us.
  // TODO: control whether we do this via an environment variable?
  setenv("GLIBCPP_FORCE_NEW", "1", false /* no overwrite*/);
  setenv("GLIBCXX_FORCE_NEW", "1", false /* no overwrite*/);

  // Now we need to make the setenv 'stick', which it may not do since
  // the env is flakey before main() is called.  But luckily stl only
  // looks at this env var the first time it tries to do an alloc, and
  // caches what it finds.  So we just cause an stl alloc here.
  string dummy("I need to be allocated");
  dummy += "!";         // so the definition of dummy isn't optimized out
#endif  /* __GLIBC__ */
}

// SysAllocator implementation
SysAllocator::~SysAllocator() {}

// Default implementation -- does nothing
MallocExtension::~MallocExtension() { }
bool MallocExtension::VerifyAllMemory() { return true; }
bool MallocExtension::VerifyNewMemory(const void* p) { return true; }
bool MallocExtension::VerifyArrayNewMemory(const void* p) { return true; }
bool MallocExtension::VerifyMallocMemory(const void* p) { return true; }

bool MallocExtension::GetNumericProperty(const char* property, size_t* value) {
  return false;
}

bool MallocExtension::SetNumericProperty(const char* property, size_t value) {
  return false;
}

void MallocExtension::GetStats(char* buffer, int length) {
  assert(length > 0);
  buffer[0] = '\0';
}

bool MallocExtension::MallocMemoryStats(int* blocks, size_t* total,
                                       int histogram[kMallocHistogramSize]) {
  *blocks = 0;
  *total = 0;
  memset(histogram, 0, sizeof(*histogram) * kMallocHistogramSize);
  return true;
}

void** MallocExtension::ReadStackTraces(int* sample_period) {
  return NULL;
}

void** MallocExtension::ReadHeapGrowthStackTraces() {
  return NULL;
}

void MallocExtension::MarkThreadIdle() {
  // Default implementation does nothing
}

void MallocExtension::MarkThreadBusy() {
  // Default implementation does nothing
}

SysAllocator* MallocExtension::GetSystemAllocator() {
  return NULL;
}

void MallocExtension::SetSystemAllocator(SysAllocator *a) {
  // Default implementation does nothing
}

void MallocExtension::ReleaseToSystem(size_t num_bytes) {
  // Default implementation does nothing
}

void MallocExtension::ReleaseFreeMemory() {
  ReleaseToSystem(static_cast<size_t>(-1));   // SIZE_T_MAX
}

void MallocExtension::SetMemoryReleaseRate(double rate) {
  // Default implementation does nothing
}

double MallocExtension::GetMemoryReleaseRate() {
  return -1.0;
}

size_t MallocExtension::GetEstimatedAllocatedSize(size_t size) {
  return size;
}

size_t MallocExtension::GetAllocatedSize(const void* p) {
  assert(GetOwnership(p) != kNotOwned);
  return 0;
}

MallocExtension::Ownership MallocExtension::GetOwnership(const void* p) {
  return kUnknownOwnership;
}

void MallocExtension::GetFreeListSizes(
    vector<MallocExtension::FreeListInfo>* v) {
  v->clear();
}

// The current malloc extension object.

static pthread_once_t module_init = PTHREAD_ONCE_INIT;
static MallocExtension* current_instance = NULL;

static void InitModule() {
  current_instance = new MallocExtension;
#ifndef NO_HEAP_CHECK
  HeapLeakChecker::IgnoreObject(current_instance);
#endif
}

MallocExtension* MallocExtension::instance() {
  perftools_pthread_once(&module_init, InitModule);
  return current_instance;
}

void MallocExtension::Register(MallocExtension* implementation) {
  perftools_pthread_once(&module_init, InitModule);
  // When running under valgrind, our custom malloc is replaced with
  // valgrind's one and malloc extensions will not work.  (Note:
  // callers should be responsible for checking that they are the
  // malloc that is really being run, before calling Register.  This
  // is just here as an extra sanity check.)
  if (!RunningOnValgrind()) {
    current_instance = implementation;
  }
}

unsigned int MallocExtension::GetBytesAllocatedOnCurrentThread() {
  // This function is added in Chromium for profiling.
#ifdef USE_TCMALLOC
  // Note that malloc_extension can be used without tcmalloc if gperftools'
  // heap-profiler is enabled without the tcmalloc memory allocator.
  return tcmalloc::ThreadCache::GetBytesAllocatedOnCurrentThread();
#else
  return 0;
#endif
}

// -----------------------------------------------------------------------
// Heap sampling support
// -----------------------------------------------------------------------

namespace {

// Accessors
uintptr_t Count(void** entry) {
  return reinterpret_cast<uintptr_t>(entry[0]);
}
uintptr_t Size(void** entry) {
  return reinterpret_cast<uintptr_t>(entry[1]);
}
uintptr_t Depth(void** entry) {
  return reinterpret_cast<uintptr_t>(entry[2]);
}
void* PC(void** entry, int i) {
  return entry[3+i];
}

void PrintCountAndSize(MallocExtensionWriter* writer,
                       uintptr_t count, uintptr_t size) {
  char buf[100];
  snprintf(buf, sizeof(buf),
           "%6" PRIu64 ": %8" PRIu64 " [%6" PRIu64 ": %8" PRIu64 "] @",
           static_cast<uint64>(count),
           static_cast<uint64>(size),
           static_cast<uint64>(count),
           static_cast<uint64>(size));
  writer->append(buf, strlen(buf));
}

void PrintHeader(MallocExtensionWriter* writer,
                 const char* label, void** entries) {
  // Compute the total count and total size
  uintptr_t total_count = 0;
  uintptr_t total_size = 0;
  for (void** entry = entries; Count(entry) != 0; entry += 3 + Depth(entry)) {
    total_count += Count(entry);
    total_size += Size(entry);
  }

  const char* const kTitle = "heap profile: ";
  writer->append(kTitle, strlen(kTitle));
  PrintCountAndSize(writer, total_count, total_size);
  writer->append(" ", 1);
  writer->append(label, strlen(label));
  writer->append("\n", 1);
}

void PrintStackEntry(MallocExtensionWriter* writer, void** entry) {
  PrintCountAndSize(writer, Count(entry), Size(entry));

  for (int i = 0; i < Depth(entry); i++) {
    char buf[32];
    snprintf(buf, sizeof(buf), " %p", PC(entry, i));
    writer->append(buf, strlen(buf));
  }
  writer->append("\n", 1);
}

}

void MallocExtension::GetHeapSample(MallocExtensionWriter* writer) {
  int sample_period = 0;
  void** entries = ReadStackTraces(&sample_period);
  if (entries == NULL) {
    const char* const kErrorMsg =
        "This malloc implementation does not support sampling.\n"
        "As of 2005/01/26, only tcmalloc supports sampling, and\n"
        "you are probably running a binary that does not use\n"
        "tcmalloc.\n";
    writer->append(kErrorMsg, strlen(kErrorMsg));
    return;
  }

  char label[32];
  sprintf(label, "heap_v2/%d", sample_period);
  PrintHeader(writer, label, entries);
  for (void** entry = entries; Count(entry) != 0; entry += 3 + Depth(entry)) {
    PrintStackEntry(writer, entry);
  }
  delete[] entries;

  DumpAddressMap(writer);
}

void MallocExtension::GetHeapGrowthStacks(MallocExtensionWriter* writer) {
  void** entries = ReadHeapGrowthStackTraces();
  if (entries == NULL) {
    const char* const kErrorMsg =
        "This malloc implementation does not support "
        "ReadHeapGrowthStackTraces().\n"
        "As of 2005/09/27, only tcmalloc supports this, and you\n"
        "are probably running a binary that does not use tcmalloc.\n";
    writer->append(kErrorMsg, strlen(kErrorMsg));
    return;
  }

  // Do not canonicalize the stack entries, so that we get a
  // time-ordered list of stack traces, which may be useful if the
  // client wants to focus on the latest stack traces.
  PrintHeader(writer, "growth", entries);
  for (void** entry = entries; Count(entry) != 0; entry += 3 + Depth(entry)) {
    PrintStackEntry(writer, entry);
  }
  delete[] entries;

  DumpAddressMap(writer);
}

void MallocExtension::Ranges(void* arg, RangeFunction func) {
  // No callbacks by default
}

// These are C shims that work on the current instance.

#define C_SHIM(fn, retval, paramlist, arglist)          \
  extern "C" PERFTOOLS_DLL_DECL retval MallocExtension_##fn paramlist {    \
    return MallocExtension::instance()->fn arglist;     \
  }

C_SHIM(VerifyAllMemory, int, (void), ());
C_SHIM(VerifyNewMemory, int, (const void* p), (p));
C_SHIM(VerifyArrayNewMemory, int, (const void* p), (p));
C_SHIM(VerifyMallocMemory, int, (const void* p), (p));
C_SHIM(MallocMemoryStats, int,
       (int* blocks, size_t* total, int histogram[kMallocHistogramSize]),
       (blocks, total, histogram));

C_SHIM(GetStats, void,
       (char* buffer, int buffer_length), (buffer, buffer_length));
C_SHIM(GetNumericProperty, int,
       (const char* property, size_t* value), (property, value));
C_SHIM(SetNumericProperty, int,
       (const char* property, size_t value), (property, value));

C_SHIM(MarkThreadIdle, void, (void), ());
C_SHIM(MarkThreadBusy, void, (void), ());
C_SHIM(ReleaseFreeMemory, void, (void), ());
C_SHIM(ReleaseToSystem, void, (size_t num_bytes), (num_bytes));
C_SHIM(GetEstimatedAllocatedSize, size_t, (size_t size), (size));
C_SHIM(GetAllocatedSize, size_t, (const void* p), (p));

// Can't use the shim here because of the need to translate the enums.
extern "C"
MallocExtension_Ownership MallocExtension_GetOwnership(const void* p) {
  return static_cast<MallocExtension_Ownership>(
      MallocExtension::instance()->GetOwnership(p));
}