Instrumenting CopyData to analyze its slowing down

net/url_request/url_request_simple_job.cc

 // 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 "net/url_request/url_request_simple_job.h"
 
 #include <vector>
 
 #include "base/bind.h"
 #include "base/compiler_specific.h"
 #include "base/memory/ref_counted_memory.h"
 #include "base/message_loop/message_loop.h"
 #include "base/profiler/scoped_tracker.h"
 #include "base/threading/worker_pool.h"
 #include "net/base/io_buffer.h"
 #include "net/base/net_errors.h"
 #include "net/http/http_request_headers.h"
 #include "net/http/http_util.h"
 #include "net/url_request/url_request_status.h"
 
 namespace net {
 
 namespace {
 
 void CopyData(const scoped_refptr<IOBuffer>& buf,
               int buf_size,
               const scoped_refptr<base::RefCountedMemory>& data,
               int64 data_offset) {
+  // TODO(vadimt): Remove ScopedTracker below once crbug.com/422489 is fixed.
+  tracked_objects::ScopedTracker tracking_profile(
+      FROM_HERE_WITH_EXPLICIT_FUNCTION("422489 CopyData"));
+
   memcpy(buf->data(), data->front() + data_offset, buf_size);
 }
 
 }  // namespace
 
 URLRequestSimpleJob::URLRequestSimpleJob(URLRequest* request,
                                          NetworkDelegate* network_delegate)
     : URLRangeRequestJob(request, network_delegate),
       next_data_offset_(0),
       task_runner_(base::WorkerPool::GetTaskRunner(false)),
@@ skipping 135 matching lines @@
     next_data_offset_ = byte_range_.first_byte_position();
     set_expected_content_size(byte_range_.last_byte_position() -
                               next_data_offset_ + 1);
     NotifyHeadersComplete();
   } else {
     NotifyStartError(URLRequestStatus(URLRequestStatus::FAILED, result));
   }
 }
 
 }  // namespace net