Initialize TaskScheduler in all child processes.

content/child/child_process.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 "content/child/child_process.h"
 
 #include <string.h>
 
 #include "base/lazy_instance.h"
 #include "base/message_loop/message_loop.h"
 #include "base/metrics/statistics_recorder.h"
 #include "base/process/process_handle.h"
 #include "base/single_thread_task_runner.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/utf_string_conversions.h"
+#include "base/task_scheduler/task_scheduler.h"
 #include "base/threading/thread.h"
 #include "base/threading/thread_local.h"
 #include "build/build_config.h"
 #include "content/child/child_thread_impl.h"
 
 #if defined(OS_ANDROID)
 #include "base/debug/debugger.h"
 #endif
 
 #if defined(OS_POSIX) && !defined(OS_ANDROID)
@@ skipping 14 matching lines @@
 ChildProcess::ChildProcess(base::ThreadPriority io_thread_priority)
     : ref_count_(0),
       shutdown_event_(base::WaitableEvent::ResetPolicy::MANUAL,
                       base::WaitableEvent::InitialState::NOT_SIGNALED),
       io_thread_("Chrome_ChildIOThread") {
   DCHECK(!g_lazy_tls.Pointer()->Get());
   g_lazy_tls.Pointer()->Set(this);
 
   base::StatisticsRecorder::Initialize();
 
+  // Initialize TaskScheduler if not already done. A TaskScheduler may already
+  // exist when ChildProcess is instantiated in the browser process or in a
+  // test process.
+  if (!base::TaskScheduler::GetInstance()) {
+    InitializeTaskScheduler();
+    DCHECK(base::TaskScheduler::GetInstance());
+    initialized_task_scheduler_ = true;
+  }
+
   // We can't recover from failing to start the IO thread.
   base::Thread::Options thread_options(base::MessageLoop::TYPE_IO, 0);
   thread_options.priority = io_thread_priority;
 #if defined(OS_ANDROID)
   // TODO(reveman): Remove this in favor of setting it explicitly for each type
   // of process.
   thread_options.priority = base::ThreadPriority::DISPLAY;
 #endif
   CHECK(io_thread_.StartWithOptions(thread_options));
 }
@@ skipping 13 matching lines @@
       main_thread_.reset();
     } else {
       // Leak the main_thread_. See a comment in
       // RenderThreadImpl::ShouldBeDestroyed.
       main_thread_.release();
     }
   }
 
   g_lazy_tls.Pointer()->Set(NULL);
   io_thread_.Stop();
+
+  if (initialized_task_scheduler_) {
+    DCHECK(base::TaskScheduler::GetInstance());
+    base::TaskScheduler::GetInstance()->Shutdown();
+  }
 }
 
 ChildThreadImpl* ChildProcess::main_thread() {
   return main_thread_.get();
 }
 
 void ChildProcess::set_main_thread(ChildThreadImpl* thread) {
   main_thread_.reset(thread);
 }
 
@@ skipping 62 matching lines @@
   struct sigaction sa;
   memset(&sa, 0, sizeof(sa));
   sa.sa_handler = SigUSR1Handler;
   sigaction(SIGUSR1, &sa, NULL);
 
   pause();
 #endif  // defined(OS_ANDROID)
 #endif  // defined(OS_POSIX)
 }
 
+void ChildProcess::InitializeTaskScheduler() {
+  constexpr int kMaxThreads = 2;
+  base::TaskScheduler::CreateAndSetSimpleTaskScheduler(kMaxThreads);
+}
+
 }  // namespace content