Resume the main job immediately when QUIC job fails, not wait for the head start timer to exprie

net/http/http_stream_factory_impl_job_controller.cc

 // Copyright (c) 2016 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/http/http_stream_factory_impl_job_controller.h"
 
 #include <memory>
 #include <string>
 #include <utility>
 
@@ skipping 45 matching lines @@
     bool is_preconnect)
     : factory_(factory),
       session_(session),
       job_factory_(job_factory),
       request_(nullptr),
       delegate_(delegate),
       is_preconnect_(is_preconnect),
       alternative_job_net_error_(OK),
       job_bound_(false),
       main_job_is_blocked_(false),
+      main_job_is_resumed_(false),
       bound_job_(nullptr),
       can_start_alternative_proxy_job_(false),
       privacy_mode_(PRIVACY_MODE_DISABLED),
       net_log_(
           NetLogWithSource::Make(session->net_log(),
                                  NetLogSourceType::HTTP_STREAM_JOB_CONTROLLER)),
       ptr_factory_(this) {
   DCHECK(factory);
   net_log_.BeginEvent(NetLogEventType::HTTP_STREAM_JOB_CONTROLLER,
                       base::Bind(&NetLogJobControllerCallback,
@@ skipping 464 matching lines @@
     Job* job,
     const ConnectionAttempts& attempts) {
   if (is_preconnect_ || (job_bound_ && bound_job_ != job))
     return;
 
   DCHECK(request_);
   request_->AddConnectionAttempts(attempts);
 }
 
 void HttpStreamFactoryImpl::JobController::ResumeMainJob() {
+  if (main_job_is_resumed_)
+    return;
+
+  main_job_is_resumed_ = true;
   main_job_->net_log().AddEvent(
       NetLogEventType::HTTP_STREAM_JOB_DELAYED,
       base::Bind(&NetLogHttpStreamJobDelayCallback, main_job_wait_time_));
 
   main_job_->Resume();
   main_job_wait_time_ = base::TimeDelta();
 }
 
 void HttpStreamFactoryImpl::JobController::MaybeResumeMainJob(
     Job* job,
     const base::TimeDelta& delay) {
+  DCHECK(delay == base::TimeDelta() || delay == main_job_wait_time_);
   DCHECK(job == main_job_.get() || job == alternative_job_.get());
 
-  if (!main_job_is_blocked_ || job != alternative_job_.get() || !main_job_)
+  if (main_job_is_resumed_ || job != alternative_job_.get() || !main_job_)
     return;
 
-  main_job_is_blocked_ = false;
+  if (!main_job_->is_waiting()) {
+    main_job_is_blocked_ = false;
+    return;
+  }
 
-  if (!main_job_->is_waiting())
-    return;
+  if (!main_job_is_blocked_) {
+    // A task has been posted earlier to resume the main job, though not
+    // executed. This task will now resume the main job immediately.
+    main_job_wait_time_ = base::TimeDelta();
+    DCHECK(delay == base::TimeDelta());

[Ryan Hamilton, 2017/02/15 00:07:02]

I don't quite understand this block. I would think that we would unconditionally
do:

main_job_wait_time_ = delay;

[Zhongyi Shi, 2017/02/15 00:26:58]

Done.

+  }
 
   base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
       FROM_HERE,
       base::Bind(&HttpStreamFactoryImpl::JobController::ResumeMainJob,
                  ptr_factory_.GetWeakPtr()),
-      main_job_wait_time_);
+      delay);
+  main_job_is_blocked_ = false;
 }
 
 void HttpStreamFactoryImpl::JobController::OnConnectionInitialized(Job* job,
                                                                    int rv) {
   if (rv != OK) {
     // Resume the main job as there's an error raised in connection
     // initiation.
     return MaybeResumeMainJob(job, main_job_wait_time_);
   }
 }
@@ skipping 570 matching lines @@
     return;
   DCHECK(alternative_job_->alternative_proxy_server().is_valid());
   alternative_job_->Start(request_->stream_type());
 }
 
 bool HttpStreamFactoryImpl::JobController::IsJobOrphaned(Job* job) const {
   return !request_ || (job_bound_ && bound_job_ != job);
 }
 
 }  // namespace net