Disallow UI/IO thread blocking on any other thread.

base/threading/sequenced_worker_pool.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 "base/threading/sequenced_worker_pool.h"
 
 #include <list>
 #include <map>
 #include <set>
 #include <utility>
 #include <vector>
 
 #include "base/atomicops.h"
 #include "base/callback.h"
 #include "base/compiler_specific.h"
 #include "base/logging.h"
 #include "base/memory/linked_ptr.h"
 #include "base/message_loop_proxy.h"
 #include "base/metrics/histogram.h"
 #include "base/stl_util.h"
 #include "base/stringprintf.h"
 #include "base/synchronization/condition_variable.h"
 #include "base/synchronization/lock.h"
 #include "base/threading/platform_thread.h"
 #include "base/threading/simple_thread.h"
+#include "base/threading/thread_restrictions.h"
 #include "base/time.h"
 #include "base/tracked_objects.h"
 
 #if defined(OS_MACOSX)
 #include "base/mac/scoped_nsautorelease_pool.h"
 #endif
 
 namespace base {
 
 namespace {
@@ skipping 582 matching lines @@
 
   // If we're here, then something is blocking shutdown.  So wait for
   // CanShutdown() to go to true.
 
   if (testing_observer_)
     testing_observer_->WillWaitForShutdown();
 
   TimeTicks shutdown_wait_begin = TimeTicks::Now();
 
   {
+    base::ThreadRestrictions::ScopedAllowWait allow_wait;
     AutoLock lock(lock_);
     while (!CanShutdown())
       can_shutdown_cv_.Wait();
   }
   UMA_HISTOGRAM_TIMES("SequencedWorkerPool.ShutdownDelayTime",
                       TimeTicks::Now() - shutdown_wait_begin);
 }
 
 void SequencedWorkerPool::Inner::ThreadLoop(Worker* this_worker) {
   {
@@ skipping 424 matching lines @@
 void SequencedWorkerPool::SignalHasWorkForTesting() {
   inner_->SignalHasWorkForTesting();
 }
 
 void SequencedWorkerPool::Shutdown() {
   DCHECK(constructor_message_loop_->BelongsToCurrentThread());
   inner_->Shutdown();
 }
 
 }  // namespace base