Route calls to tcmalloc MallocExtension through allocator agnostic interface

Our various libraries should not be picking or depending on a particular
allocator choice - that should be an application level choice. This creates
a generic AllocatorExtension interface that can optionally be backed by
entry points to a particular allocator's MallocExtension interface if the
application chooses to.

BUG=125003
TEST=compiles, chrome://tcmalloc works


Review URL: http://codereview.chromium.org/10239012

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@134434 0039d316-1c4b-4281-b951-d872f2087c98

7 files changed, 209 insertions, 0 deletions

diff --git a/base/allocator/allocator.gyp b/base/allocator/allocator.gyp
index ee07ecc..7b1058c 100644
--- a/base/allocator/allocator.gyp
+++ b/base/allocator/allocator.gyp
@@ -427,7 +427,22 @@
         }],
       ],
     },
+    {
+      # This library is linked in to libbase and allocator_unittests.
+      # It can't depend on either and nothing else should depend on it -
+      # all other code should use the interfaced provided by libbase.
+      'target_name': 'allocator_extension_thunks',
+      'type': 'static_library',
+      'sources': [
+        'allocator_extension_thunks.cc',
+        'allocator_extension_thunks.h',
       ],
+      'toolsets': ['host', 'target'],
+      'include_dirs': [
+        '../../'
+      ],
+    },
+   ],
   'conditions': [
     ['OS=="win"', {
       'targets': [
@@ -456,6 +471,7 @@
           'type': 'executable',
           'dependencies': [
             'allocator',
+            'allocator_extension_thunks',
             '../../testing/gtest.gyp:gtest',
           ],
           'include_dirs': [
@@ -470,6 +486,23 @@
             '../profiler/alternate_timer.h',
           ],
         },
+        {
+          'target_name': 'allocator_extension_thunks_win64',
+          'type': 'static_library',
+          'sources': [
+            'allocator_extension_thunks.cc',
+            'allocator_extension_thunks.h',
+          ],
+          'toolsets': ['host', 'target'],
+          'include_dirs': [
+            '../../'
+          ],
+          'configurations': {
+            'Common_Base': {
+              'msvs_target_platform': 'x64',
+            },
+          },
+        },
       ],
     }],
   ],
diff --git a/base/allocator/allocator_extension.cc b/base/allocator/allocator_extension.cc
new file mode 100644
index 0000000..7ae11da
--- /dev/null
+++ b/base/allocator/allocator_extension.cc
@@ -0,0 +1,42 @@
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "base/allocator/allocator_extension.h"
+
+#include "base/logging.h"
+
+namespace base {
+namespace allocator {
+
+void GetStats(char* buffer, int buffer_length) {
+  DCHECK_GT(buffer_length, 0);
+  if (thunks::GetStatsFunction* get_stats_function =
+          base::allocator::thunks::GetGetStatsFunction())
+    get_stats_function(buffer, buffer_length);
+  else
+    buffer[0] = '\0';
+}
+
+void ReleaseFreeMemory() {
+  if (thunks::ReleaseFreeMemoryFunction* release_free_memory_function =
+          base::allocator::thunks::GetReleaseFreeMemoryFunction())
+    release_free_memory_function();
+}
+
+void SetGetStatsFunction(thunks::GetStatsFunction* get_stats_function) {
+  DCHECK_EQ(base::allocator::thunks::GetGetStatsFunction(),
+            reinterpret_cast<thunks::GetStatsFunction*>(NULL));
+  base::allocator::thunks::SetGetStatsFunction(get_stats_function);
+}
+
+void SetReleaseFreeMemoryFunction(
+    thunks::ReleaseFreeMemoryFunction* release_free_memory_function) {
+  DCHECK_EQ(base::allocator::thunks::GetReleaseFreeMemoryFunction(),
+            reinterpret_cast<thunks::ReleaseFreeMemoryFunction*>(NULL));
+  base::allocator::thunks::SetReleaseFreeMemoryFunction(
+      release_free_memory_function);
+}
+
+}  // namespace allocator
+}  // namespace base
diff --git a/base/allocator/allocator_extension.h b/base/allocator/allocator_extension.h
new file mode 100644
index 0000000..d63f189
--- /dev/null
+++ b/base/allocator/allocator_extension.h
@@ -0,0 +1,45 @@
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef BASE_ALLOCATOR_ALLOCATOR_EXTENSION_H
+#define BASE_ALLOCATOR_ALLOCATOR_EXTENSION_H
+#pragma once
+
+#include "base/allocator/allocator_extension_thunks.h"
+#include "base/base_export.h"
+#include "build/build_config.h"
+
+namespace base {
+namespace allocator {
+
+// Request that the allocator print a human-readable description of the current
+// state of the allocator into a null-terminated string in the memory segment
+// buffer[0,buffer_length-1].
+//
+// |buffer| must point to a valid piece of memory
+// |buffer_length| must be > 0.
+BASE_EXPORT void GetStats(char* buffer, int buffer_length);
+
+// Request that the allocator release any free memory it knows about to the
+// system.
+BASE_EXPORT void ReleaseFreeMemory();
+
+
+// These settings allow specifying a callback used to implement the allocator
+// extension functions.  These are optional, but if set they must only be set
+// once.  These will typically called in an allocator-specific initialization
+// routine.
+//
+// No threading promises are made.  The caller is responsible for making sure
+// these pointers are set before any other threads attempt to call the above
+// functions.
+BASE_EXPORT void SetGetStatsFunction(
+    thunks::GetStatsFunction* get_stats_function);
+
+BASE_EXPORT void SetReleaseFreeMemoryFunction(
+    thunks::ReleaseFreeMemoryFunction* release_free_memory_function);
+}  // namespace allocator
+}  // namespace base
+
+#endif
diff --git a/base/allocator/allocator_extension_thunks.cc b/base/allocator/allocator_extension_thunks.cc
new file mode 100644
index 0000000..f8985a2
--- /dev/null
+++ b/base/allocator/allocator_extension_thunks.cc
@@ -0,0 +1,42 @@
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "base/allocator/allocator_extension_thunks.h"
+
+#include <cstddef> // for NULL
+
+namespace base {
+namespace allocator {
+namespace thunks {
+
+// This slightly odd translation unit exists because of the peculularity of how
+// allocator_unittests works on windows.  That target has to perform
+// tcmalloc-specific initialization on windows, but it cannot depend on base
+// otherwise.  This target sits in the middle - both libbase and
+// allocator_unittests can depend on it.
+// This file can't depend on anything else in base, including logging.
+
+static GetStatsFunction* g_get_stats_function = NULL;
+static ReleaseFreeMemoryFunction* g_release_free_memory_function = NULL;
+
+void SetGetStatsFunction(GetStatsFunction* get_stats_function) {
+  g_get_stats_function = get_stats_function;
+}
+
+GetStatsFunction* GetGetStatsFunction() {
+  return g_get_stats_function;
+}
+
+void SetReleaseFreeMemoryFunction(
+      ReleaseFreeMemoryFunction* release_free_memory_function) {
+  g_release_free_memory_function = release_free_memory_function;
+}
+
+ReleaseFreeMemoryFunction* GetReleaseFreeMemoryFunction() {
+  return g_release_free_memory_function;
+}
+
+}  // namespace thunks
+}  // namespace allocator
+}  // namespace base
diff --git a/base/allocator/allocator_extension_thunks.h b/base/allocator/allocator_extension_thunks.h
new file mode 100644
index 0000000..7c9c231
--- /dev/null
+++ b/base/allocator/allocator_extension_thunks.h
@@ -0,0 +1,30 @@
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef BASE_ALLOCATOR_ALLOCATOR_THUNKS_EXTENSION_H
+#define BASE_ALLOCATOR_ALLOCATOR_THUNKS_EXTENSION_H
+#pragma once
+
+namespace base {
+namespace allocator {
+namespace thunks {
+
+// WARNING: You probably don't want to use this file unless you are routing a
+// new allocator extension from a specific allocator implementation to base.
+// See allocator_extension.h to see the interface that base exports.
+
+typedef void GetStatsFunction(char*, int);
+void SetGetStatsFunction(GetStatsFunction* get_stats_function);
+GetStatsFunction* GetGetStatsFunction();
+
+typedef void ReleaseFreeMemoryFunction();
+void SetReleaseFreeMemoryFunction(
+    ReleaseFreeMemoryFunction* release_free_memory_function);
+ReleaseFreeMemoryFunction* GetReleaseFreeMemoryFunction();
+
+}  // namespace thunks
+}  // namespace allocator
+}  // namespace base
+
+#endif
diff --git a/base/allocator/allocator_shim.cc b/base/allocator/allocator_shim.cc
index 075828d..8728097 100644
--- a/base/allocator/allocator_shim.cc
+++ b/base/allocator/allocator_shim.cc
@@ -5,6 +5,7 @@
 #include "base/allocator/allocator_shim.h"
 
 #include <config.h>
+#include "base/allocator/allocator_extension_thunks.h"
 #include "base/profiler/alternate_timer.h"
 #include "base/sysinfo.h"
 
@@ -229,6 +230,14 @@ extern "C" intptr_t _get_heap_handle() {
   return 0;
 }
 
+static void get_stats_thunk(char* buffer, int buffer_length) {
+  MallocExtension::instance()->GetStats(buffer, buffer_length);
+}
+
+static void release_free_memory_thunk() {
+  MallocExtension::instance()->ReleaseFreeMemory();
+}
+
 // The CRT heap initialization stub.
 extern "C" int _heap_init() {
 #ifdef ENABLE_DYNAMIC_ALLOCATOR_SWITCHING
@@ -274,6 +283,10 @@ extern "C" int _heap_init() {
         tracked_objects::TIME_SOURCE_TYPE_TCMALLOC);
   }
 
+  base::allocator::thunks::SetGetStatsFunction(get_stats_thunk);
+  base::allocator::thunks::SetReleaseFreeMemoryFunction(
+      release_free_memory_thunk);
+
   return 1;
 }
 
diff --git a/base/base.gypi b/base/base.gypi
index 302f620..c5fb4cc 100644
--- a/base/base.gypi
+++ b/base/base.gypi
@@ -21,6 +21,8 @@
           'third_party/nspr/prtime.h',
           'third_party/nspr/prcpucfg_linux.h',
           'third_party/xdg_mime/xdgmime.h',
+          'allocator/allocator_extension.cc',
+          'allocator/allocator_extension.h',
           'android/base_jni_registrar.cc',
           'android/base_jni_registrar.h',
           'android/build_info.cc',
@@ -589,6 +591,7 @@
       },
       'dependencies': [
         'base_static',
+        'allocator/allocator.gyp:allocator_extension_thunks',
         '../testing/gtest.gyp:gtest_prod',
         '../third_party/modp_b64/modp_b64.gyp:modp_b64',
         'third_party/dynamic_annotations/dynamic_annotations.gyp:dynamic_annotations',
@@ -808,6 +811,7 @@
           },
           'dependencies': [
             'base_static_win64',
+            'allocator/allocator.gyp:allocator_extension_thunks_win64',
             'third_party/dynamic_annotations/dynamic_annotations.gyp:dynamic_annotations_win64',
           ],
           # TODO(gregoryd): direct_dependent_settings should be shared with the