blob: 0bb59ab2e3a4d396662ce190b110998f5a498169 [file] [log] [blame]
// Copyright 2017 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/task/task_scheduler/environment_config.h"
#include "base/synchronization/lock.h"
#include "base/threading/platform_thread.h"
#include "build/build_config.h"
namespace base {
namespace internal {
size_t GetEnvironmentIndexForTraits(const TaskTraits& traits) {
const bool is_background =
traits.priority() == base::TaskPriority::BEST_EFFORT;
if (traits.may_block() || traits.with_base_sync_primitives())
return is_background ? BACKGROUND : FOREGROUND;
bool CanUseBackgroundPriorityForSchedulerWorker() {
// When Lock doesn't handle multiple thread priorities, run all
// SchedulerWorker with a normal priority to avoid priority inversion when a
// thread running with a normal priority tries to acquire a lock held by a
// thread running with a background priority.
if (!Lock::HandlesMultipleThreadPriorities())
return false;
#if !defined(OS_ANDROID)
// When thread priority can't be increased to NORMAL, run all threads with a
// NORMAL priority to avoid priority inversions on shutdown (TaskScheduler
// increases BACKGROUND threads priority to NORMAL on shutdown while resolving
// remaining shutdown blocking tasks).
// This is ignored on Android, because it doesn't have a clean shutdown phase.
if (!PlatformThread::CanIncreaseThreadPriority(ThreadPriority::NORMAL))
return false;
#endif // defined(OS_ANDROID)
return true;
} // namespace internal
} // namespace base