linux: TCMalloc-based C++ heap profiler.

Requires compiling with linux_use_tcmalloc=1.

When enabled by --heap-profiler flag in test_shell exposes
chromium.HeapProfiler object to JavaScript. The object has three
methods:
o start() -- starts profiling
o dump() -- dumps data accumulated since start() to file
named like chromium-YYYY-MM-DD-TS.heap
o stop() -- stops profiling.

Output can be analyzed by third_party/tcmalloc/tcmalloc/src/pprof.
For example:
$ third_party/tcmalloc/tcmalloc/src/pprof \
sconsbuild/Release/test_shell \
chromium-2009-11-06-1234567890.heap

See http://code.google.com/p/google-perftools/ for details on how to
use pprof.

Patch contributed by vitalyr@chromium.org.  Original review at
http://codereview.chromium.org/377010/show.

TBR=vitalyr

Review URL: http://codereview.chromium.org/390015

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@31688 0039d316-1c4b-4281-b951-d872f2087c98

8 files changed, 154 insertions, 5 deletions

diff --git a/base/base.gyp b/base/base.gyp
index 31d9d49..52ffe09 100644
--- a/base/base.gyp
+++ b/base/base.gyp
@@ -376,9 +376,6 @@
       ],
       'conditions': [
         [ 'OS == "linux" or OS == "freebsd"', {
-            'variables' : {
-              'linux_use_tcmalloc%': 0,
-            },
             'sources/': [ ['exclude', '_(mac|win|chromeos)\\.cc$'],
                           ['exclude', '\\.mm?$' ] ],
             'conditions': [
diff --git a/build/common.gypi b/build/common.gypi
index a77a13c..1cc8cca 100644
--- a/build/common.gypi
+++ b/build/common.gypi
@@ -176,6 +176,9 @@
     # Strip the binary after dumping symbols.
     'linux_strip_binary%': 0,
 
+    # Enable TCMalloc.
+    'linux_use_tcmalloc%': 0,
+
     # Set to select the Title Case versions of strings in GRD files.
     'use_titlecase_in_grd_files%': 0,
 
@@ -709,6 +712,9 @@
               }]
             ],
           }],
+          ['linux_use_tcmalloc==1', {
+            'defines': ['LINUX_USE_TCMALLOC'],
+          }],
         ],
       },
     }],
diff --git a/webkit/extensions/v8/heap_profiler_extension.cc b/webkit/extensions/v8/heap_profiler_extension.cc
new file mode 100644
index 0000000..058a5c2
--- /dev/null
+++ b/webkit/extensions/v8/heap_profiler_extension.cc
@@ -0,0 +1,111 @@
+// Copyright (c) 2006-2009 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 "webkit/extensions/v8/heap_profiler_extension.h"
+
+#include "base/basictypes.h"
+
+#if defined(LINUX_USE_TCMALLOC)
+#include "third_party/tcmalloc/tcmalloc/src/google/heap-profiler.h"
+#endif
+
+namespace extensions_v8 {
+
+namespace {
+
+const char kHeapProfilerExtensionName[] = "v8/HeapProfiler";
+
+class HeapProfilerWrapper : public v8::Extension {
+ public:
+  HeapProfilerWrapper()
+      : v8::Extension(kHeapProfilerExtensionName,
+                      "if (typeof(chromium) == 'undefined') {"
+                      "  chromium = {};"
+                      "}"
+                      "(function() {"
+                      "  native function HeapProfilerStart();"
+                      "  native function HeapProfilerStop();"
+                      "  native function HeapProfilerDump();"
+                      "  chromium.HeapProfiler = {};"
+                      "  chromium.HeapProfiler.start = function(opt_prefix) {"
+                      "    var prefix = opt_prefix;"
+                      "    if (!prefix) {"
+                      "      var d = new Date();"
+                      "      prefix = \"chromium-\" + "
+                      "               (1900 + d.getYear()) + "
+                      "               \"-\" + d.getMonth() + "
+                      "               \"-\" + d.getDay() + "
+                      "               \"-\" + d.getTime();"
+                      "    }"
+                      "    HeapProfilerStart(prefix);"
+                      "  };"
+                      "  chromium.HeapProfiler.stop = function() {"
+                      "    HeapProfilerStop();"
+                      "  };"
+                      "  chromium.HeapProfiler.dump = function(opt_reason) {"
+                      "    HeapProfilerDump(opt_reason || \"\");"
+                      "  };"
+                      "})();") {}
+
+  virtual v8::Handle<v8::FunctionTemplate> GetNativeFunction(
+      v8::Handle<v8::String> name) {
+    if (name->Equals(v8::String::New("HeapProfilerStart"))) {
+      return v8::FunctionTemplate::New(HeapProfilerStart);
+    } else if (name->Equals(v8::String::New("HeapProfilerStop"))) {
+      return v8::FunctionTemplate::New(HeapProfilerStop);
+    } else if (name->Equals(v8::String::New("HeapProfilerDump"))) {
+      return v8::FunctionTemplate::New(HeapProfilerDump);
+    }
+    return v8::Handle<v8::FunctionTemplate>();
+  }
+
+#if defined(LINUX_USE_TCMALLOC)
+  static v8::Handle<v8::Value> HeapProfilerStart(const v8::Arguments& args) {
+    if (args.Length() >= 1 && args[0]->IsString()) {
+      v8::Local<v8::String> js_prefix = args[0]->ToString();
+      char prefix[256];
+      js_prefix->WriteAscii(prefix, 0, arraysize(prefix) - 1);
+      ::HeapProfilerStart(prefix);
+    }
+    return v8::Undefined();
+  }
+
+  static v8::Handle<v8::Value> HeapProfilerStop(const v8::Arguments& args) {
+    ::HeapProfilerStop();
+    return v8::Undefined();
+  }
+
+  static v8::Handle<v8::Value> HeapProfilerDump(const v8::Arguments& args) {
+    if (args.Length() >= 1 && args[0]->IsString()) {
+      v8::Local<v8::String> js_reason = args[0]->ToString();
+      char reason[256];
+      js_reason->WriteAscii(reason, 0, arraysize(reason) - 1);
+      ::HeapProfilerDump(reason);
+    }
+    return v8::Undefined();
+  }
+
+#else
+
+  static v8::Handle<v8::Value> HeapProfilerStart(const v8::Arguments& args) {
+    return v8::Undefined();
+  }
+
+  static v8::Handle<v8::Value> HeapProfilerStop(const v8::Arguments& args) {
+    return v8::Undefined();
+  }
+
+  static v8::Handle<v8::Value> HeapProfilerDump(const v8::Arguments& args) {
+    return v8::Undefined();
+  }
+#endif
+};
+
+}  // namespace
+
+v8::Extension* HeapProfilerExtension::Get() {
+  return new HeapProfilerWrapper;
+}
+
+}  // namespace extensions_v8
diff --git a/webkit/extensions/v8/heap_profiler_extension.h b/webkit/extensions/v8/heap_profiler_extension.h
new file mode 100644
index 0000000..8bdbf90
--- /dev/null
+++ b/webkit/extensions/v8/heap_profiler_extension.h
@@ -0,0 +1,23 @@
+// Copyright (c) 2006-2009 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.
+
+// HeapProfilerExtension is a V8 extension to expose a JS function for
+// dumping native heap profiles.  This should only be used for
+// debugging.
+
+#ifndef WEBKIT_EXTENSIONS_V8_HEAP_PROFILER_EXTENSION_H_
+#define WEBKIT_EXTENSIONS_V8_HEAP_PROFILER_EXTENSION_H_
+
+#include "v8/include/v8.h"
+
+namespace extensions_v8 {
+
+class HeapProfilerExtension {
+ public:
+  static v8::Extension* Get();
+};
+
+}  // namespace extensions_v8
+
+#endif  // WEBKIT_EXTENSIONS_V8_HEAP_PROFILER_EXTENSION_H_
diff --git a/webkit/tools/test_shell/test_shell_main.cc b/webkit/tools/test_shell/test_shell_main.cc
index b069b2f..ea2d625 100644
--- a/webkit/tools/test_shell/test_shell_main.cc
+++ b/webkit/tools/test_shell/test_shell_main.cc
@@ -29,6 +29,7 @@
 #include "webkit/glue/webkit_glue.h"
 #include "webkit/glue/window_open_disposition.h"
 #include "webkit/extensions/v8/gc_extension.h"
+#include "webkit/extensions/v8/heap_profiler_extension.h"
 #include "webkit/extensions/v8/playback_extension.h"
 #include "webkit/extensions/v8/profiler_extension.h"
 #include "webkit/tools/test_shell/simple_resource_loader_bridge.h"
@@ -225,6 +226,11 @@ int main(int argc, char* argv[]) {
         extensions_v8::ProfilerExtension::Get());
   }
 
+  if (parsed_command_line.HasSwitch(test_shell::kHeapProfiler)) {
+    WebScriptController::registerExtension(
+        extensions_v8::HeapProfilerExtension::Get());
+  }
+
   // Load and initialize the stats table.  Attempt to construct a somewhat
   // unique name to isolate separate instances from each other.
   StatsTable *table = new StatsTable(
diff --git a/webkit/tools/test_shell/test_shell_switches.cc b/webkit/tools/test_shell/test_shell_switches.cc
index 1142ee1..d0bf04c 100644
--- a/webkit/tools/test_shell/test_shell_switches.cc
+++ b/webkit/tools/test_shell/test_shell_switches.cc
@@ -82,4 +82,7 @@ extern const char kGDB[] = "gdb";
 // Make functions of the Profiler class available in javascript
 extern const char kProfiler[] = "profiler";
 
+// Make functions of the HeapProfiler class available in javascript
+extern const char kHeapProfiler[] = "heap-profiler";
+
 }  // namespace test_shell
diff --git a/webkit/tools/test_shell/test_shell_switches.h b/webkit/tools/test_shell/test_shell_switches.h
index d580695..0330e0a 100644
--- a/webkit/tools/test_shell/test_shell_switches.h
+++ b/webkit/tools/test_shell/test_shell_switches.h
@@ -33,6 +33,7 @@ extern const char kAllowScriptsToCloseWindows[];
 extern const char kCheckLayoutTestSystemDeps[];
 extern const char kGDB[];
 extern const char kProfiler[];
+extern const char kHeapProfiler[];
 
 }  // namespace test_shell
 
diff --git a/webkit/webkit.gyp b/webkit/webkit.gyp
index 9bf19c7..b6212a6 100644
--- a/webkit/webkit.gyp
+++ b/webkit/webkit.gyp
@@ -379,18 +379,20 @@
 
         # These files used to be built in the webcore target, but moved here
         # since part of glue.
+        'extensions/v8/benchmarking_extension.cc',
+        'extensions/v8/benchmarking_extension.h',
         'extensions/v8/gc_extension.cc',
         'extensions/v8/gc_extension.h',
         'extensions/v8/gears_extension.cc',
         'extensions/v8/gears_extension.h',
+        'extensions/v8/heap_profiler_extension.cc',
+        'extensions/v8/heap_profiler_extension.h',
         'extensions/v8/interval_extension.cc',
         'extensions/v8/interval_extension.h',
         'extensions/v8/playback_extension.cc',
         'extensions/v8/playback_extension.h',
         'extensions/v8/profiler_extension.cc',
         'extensions/v8/profiler_extension.h',
-        'extensions/v8/benchmarking_extension.cc',
-        'extensions/v8/benchmarking_extension.h',
 
       ],
       # When glue is a dependency, it needs to be a hard dependency.