Add a benchmarking_extension API to call TCMalloc's HeapProfilerDump().

chrome/renderer/benchmarking_extension.cc

Index: chrome/renderer/benchmarking_extension.cc
diff --git a/chrome/renderer/benchmarking_extension.cc b/chrome/renderer/benchmarking_extension.cc
index f74714f52c9a22ae9a8288c6065e15ca3ef1cadc..8119aaf40088103fe1080e0b9dcf26b7feb43b2a 100644
--- a/chrome/renderer/benchmarking_extension.cc
+++ b/chrome/renderer/benchmarking_extension.cc
@@ -5,11 +5,15 @@
 #include "chrome/renderer/benchmarking_extension.h"
 
 #include "base/command_line.h"
+#include "base/string_util.h"
 #include "base/metrics/stats_table.h"
 #include "base/time.h"
 #include "chrome/common/benchmarking_messages.h"
 #include "content/public/common/content_switches.h"
 #include "content/public/renderer/render_thread.h"
+#if !defined(NO_TCMALLOC) && (defined(OS_LINUX) || defined(OS_CHROMEOS))
+#include "third_party/tcmalloc/chromium/src/gperftools/heap-profiler.h"
+#endif  // !defined(NO_TCMALLOC) && (defined(OS_LINUX) || defined(OS_CHROMEOS))
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebCache.h"
 #include "v8/include/v8.h"
 
@@ -57,6 +61,12 @@ class BenchmarkingWrapper : public v8::Extension {
         "  native function IsSingleProcess();"
         "  return IsSingleProcess();"
         "};"
+#if !defined(NO_TCMALLOC) && (defined(OS_LINUX) || defined(OS_CHROMEOS))
+        "chrome.benchmarking.heapProfilerDump = function(reason) {"
+        "  native function HeapProfilerDump();"
+        "  HeapProfilerDump(reason);"
+        "};"
+#endif  // !defined(NO_TCMALLOC) && (defined(OS_LINUX) || defined(OS_CHROMEOS))
         "chrome.Interval = function() {"
         "  var start_ = 0;"
         "  var stop_ = 0;"
@@ -95,6 +105,10 @@ class BenchmarkingWrapper : public v8::Extension {
       return v8::FunctionTemplate::New(GetCounter);
     } else if (name->Equals(v8::String::New("IsSingleProcess"))) {
       return v8::FunctionTemplate::New(IsSingleProcess);
+#if !defined(NO_TCMALLOC) && (defined(OS_LINUX) || defined(OS_CHROMEOS))
+    } else if (name->Equals(v8::String::New("HeapProfilerDump"))) {
+      return v8::FunctionTemplate::New(HeapProfilerDump);
+#endif  // !defined(NO_TCMALLOC) && (defined(OS_LINUX) || defined(OS_CHROMEOS))
     } else if (name->Equals(v8::String::New("HiResTime"))) {
       return v8::FunctionTemplate::New(HiResTime);
     }
@@ -159,6 +173,19 @@ class BenchmarkingWrapper : public v8::Extension {
        CommandLine::ForCurrentProcess()->HasSwitch(switches::kSingleProcess));
   }
 
+#if !defined(NO_TCMALLOC) && (defined(OS_LINUX) || defined(OS_CHROMEOS))

[nduca, 2013/02/06 07:26:42]

Awesome. Now, we've been trying to split apart this monolithic extension [so
that is easy to reason about the side effects of different patches]. While these
changes aren't themselves controversial, I think it'd be in keeping with that
general desire to pull this out to its own extension, maybe we can call it the
memory-benchmarking extension? We can then put other memory related extensions
as we find need for them.

https://codereview.chromium.org/11801024/ has an example of danhn doing this.

[Dai Mikurube (NOT FULLTIME), 2013/02/06 10:51:15]

Hmm, do you mean we should have new memory_benchmarking_extension.{cc|h} instead
of adding this function to benchmarking_extension.cc?

It's ok to do that.  Are all files to be changed are the following?

1) chrome/chrome_renderer.gypi ... add memory_benchmarking_extension
2) chrome/renderer/chrome_content_renderer_client.cc ... register
3) chrome/renderer/memory_benchmarking_extension.h
4) chrome/renderer/memory_benchmarking_extension.cc

+  static v8::Handle<v8::Value> HeapProfilerDump(const v8::Arguments& args) {
+    char reason[256];
+    if (args.Length() && args[0]->IsString())
+      args[0]->ToString()->WriteAscii(reason, 0, sizeof(reason) - 1);
+    else
+      base::strlcpy(reason, "benchmarking_extension", sizeof(reason));
+
+    ::HeapProfilerDump(reason);
+    return v8::Undefined();
+  }
+#endif  // !defined(NO_TCMALLOC) && (defined(OS_LINUX) || defined(OS_CHROMEOS))
+
   static v8::Handle<v8::Value> HiResTime(const v8::Arguments& args) {
     return v8::Number::New(
         static_cast<double>(base::TimeTicks::HighResNow().ToInternalValue()));