Use SequencedWorkerPool for disk operations in TraceSubscriberStdio.

content/browser/trace_controller.cc

 // Copyright (c) 2011 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 "content/browser/trace_controller.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/debug/trace_event.h"
 #include "base/string_number_conversions.h"
 #include "content/browser/trace_message_filter.h"
 #include "content/browser/trace_subscriber_stdio.h"
 #include "content/common/child_process_messages.h"
 #include "content/public/browser/browser_message_filter.h"
 #include "content/public/common/content_switches.h"
 
 using base::debug::TraceLog;
 using content::BrowserMessageFilter;
 using content::BrowserThread;
 
 namespace {
 
-class AutoStopTraceSubscriberStdio : public TraceSubscriberStdio {
+class AutoStopTraceSubscriberStdio : public content::TraceSubscriberStdio {
  public:
   AutoStopTraceSubscriberStdio(const FilePath& file_path)
       : TraceSubscriberStdio(file_path) {}
 
   static void EndStartupTrace(TraceSubscriberStdio* subscriber) {
     if (!TraceController::GetInstance()->EndTracingAsync(subscriber))
       delete subscriber;
     // else, the tracing will end asynchronously in OnEndTracingComplete().
   }
 
@@ skipping 45 matching lines @@
   if (trace_file == FilePath().AppendASCII("none"))
     return;
 
   if (trace_file.empty()) {
     // Default to saving the startup trace into the current dir.
     trace_file = FilePath().AppendASCII("chrometrace.log");
   }
   scoped_ptr<AutoStopTraceSubscriberStdio> subscriber(
       new AutoStopTraceSubscriberStdio(trace_file));
   DCHECK(can_begin_tracing(subscriber.get()));
-  if (!subscriber->IsValid()) {
-    TraceLog::GetInstance()->SetDisabled();
-    return;
-  }
 
   std::string delay_str = command_line.GetSwitchValueASCII(
       switches::kTraceStartupDuration);
   int delay_secs = 5;
   if (!delay_str.empty() && !base::StringToInt(delay_str, &delay_secs)) {
     DLOG(WARNING) << "Could not parse --" << switches::kTraceStartupDuration
         << "=" << delay_str << " defaulting to 5 (secs)";
     delay_secs = 5;
   }
 
@@ skipping 204 matching lines @@
     // this code only executes if there were child processes.
     std::vector<std::string> categories;
     TraceLog::GetInstance()->GetKnownCategories(&categories);
     BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
         base::Bind(&TraceController::OnEndTracingAck, base::Unretained(this),
                    categories));
   }
 }
 
 void TraceController::OnTraceDataCollected(
-    const scoped_refptr<TraceLog::RefCountedString>& events_str_ptr) {
+    const scoped_refptr<base::RefCountedString>& events_str_ptr) {
   // OnTraceDataCollected may be called from any browser thread, either by the
   // local event trace system or from child processes via TraceMessageFilter.
   if (!BrowserThread::CurrentlyOn(BrowserThread::UI)) {
     BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
         base::Bind(&TraceController::OnTraceDataCollected,
                    base::Unretained(this), events_str_ptr));
     return;
   }
 
   // Drop trace events if we are just getting categories.
   if (subscriber_ && !is_get_categories_)
-    subscriber_->OnTraceDataCollected(events_str_ptr->data);
+    subscriber_->OnTraceDataCollected(events_str_ptr);
 }
 
 void TraceController::OnTraceBufferFull() {
   // OnTraceBufferFull may be called from any browser thread, either by the
   // local event trace system or from child processes via TraceMessageFilter.
   if (!BrowserThread::CurrentlyOn(BrowserThread::UI)) {
     BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
         base::Bind(&TraceController::OnTraceBufferFull,
                    base::Unretained(this)));
     return;
@@ skipping 26 matching lines @@
   if (pending_bpf_ack_count_ == 1) {
     // The last ack represents local trace, so we need to ack it now. Note that
     // this code only executes if there were child processes.
     float bpf = TraceLog::GetInstance()->GetBufferPercentFull();
     BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
         base::Bind(&TraceController::OnTraceBufferPercentFullReply,
                    base::Unretained(this), bpf));
   }
 }