Adding instrumentation to locate the source of jankiness.

net/proxy/proxy_script_fetcher_impl.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/proxy/proxy_script_fetcher_impl.h"
 
 #include "base/compiler_specific.h"
 #include "base/logging.h"
 #include "base/message_loop/message_loop.h"
+#include "base/profiler/scoped_tracker.h"
 #include "base/strings/string_util.h"
 #include "net/base/data_url.h"
 #include "net/base/io_buffer.h"
 #include "net/base/load_flags.h"
 #include "net/base/net_errors.h"
 #include "net/base/net_string_util.h"
 #include "net/base/request_priority.h"
 #include "net/cert/cert_status_flags.h"
 #include "net/http/http_response_headers.h"
 #include "net/url_request/url_request_context.h"
@@ skipping 175 matching lines @@
     request->ContinueDespiteLastError();
     return;
   }
   LOG(WARNING) << "SSL certificate error when fetching PAC script, aborting.";
   // Certificate errors are in same space as net errors.
   result_code_ = MapCertStatusToNetError(ssl_info.cert_status);
   request->Cancel();
 }
 
 void ProxyScriptFetcherImpl::OnResponseStarted(URLRequest* request) {
+  // TODO(vadimt): Remove ScopedTracker below once crbug.com/423948 is fixed.
+  tracked_objects::ScopedTracker tracking_profile(
+      FROM_HERE_WITH_EXPLICIT_FUNCTION(
+          "423948 ProxyScriptFetcherImpl::OnResponseStarted"));
+
   DCHECK_EQ(request, cur_request_.get());
 
   if (!request->status().is_success()) {
     OnResponseCompleted(request);
     return;
   }
 
   // Require HTTP responses to have a success status code.
   if (request->url().SchemeIsHTTPOrHTTPS()) {
     // NOTE about status codes: We are like Firefox 3 in this respect.
@@ skipping 15 matching lines @@
       VLOG(1) << "Fetched PAC script does not have a proper mime type: "
               << mime_type;
     }
   }
 
   ReadBody(request);
 }
 
 void ProxyScriptFetcherImpl::OnReadCompleted(URLRequest* request,
                                              int num_bytes) {
+  // TODO(vadimt): Remove ScopedTracker below once crbug.com/423948 is fixed.
+  tracked_objects::ScopedTracker tracking_profile(
+      FROM_HERE_WITH_EXPLICIT_FUNCTION(
+          "423948 ProxyScriptFetcherImpl::OnReadCompleted"));
+
   DCHECK_EQ(request, cur_request_.get());
   if (ConsumeBytesRead(request, num_bytes)) {
     // Keep reading.
     ReadBody(request);
   }
 }
 
 void ProxyScriptFetcherImpl::ReadBody(URLRequest* request) {
   // Read as many bytes as are available synchronously.
   while (true) {
@@ skipping 61 matching lines @@
   // is still applicable.
   if (cur_request_id_ != id)
     return;
 
   DCHECK(cur_request_.get());
   result_code_ = ERR_TIMED_OUT;
   cur_request_->Cancel();
 }
 
 }  // namespace net