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base / task / thread_pool / environment_config.cc [blame]
// Copyright 2017 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "base/task/thread_pool/environment_config.h"
#include "base/base_switches.h"
#include "base/command_line.h"
#include "base/synchronization/lock.h"
#include "base/threading/platform_thread.h"
#include "build/build_config.h"
namespace base {
namespace internal {
namespace {
bool CanUseBackgroundThreadTypeForWorkerThreadImpl() {
// Commandline flag overrides (e.g. for experiments). Note that it may not be
// initialized yet, e.g. in cronet.
if (CommandLine::InitializedForCurrentProcess() &&
CommandLine::ForCurrentProcess()->HasSwitch(
switches::kEnableBackgroundThreadPool)) {
return true;
}
// When Lock doesn't handle multiple thread priorities, run all
// WorkerThread 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 !BUILDFLAG(IS_ANDROID)
// When thread type can't be increased to kNormal, run all threads with a
// kNormal thread type to avoid priority inversions on shutdown
// (ThreadPoolImpl increases kBackground threads type to kNormal on shutdown
// while resolving remaining shutdown blocking tasks).
//
// This is ignored on Android, because it doesn't have a clean shutdown phase.
if (!PlatformThread::CanChangeThreadType(ThreadType::kBackground,
ThreadType::kDefault))
return false;
#endif // BUILDFLAG(IS_ANDROID)
return true;
}
bool CanUseUtilityThreadTypeForWorkerThreadImpl() {
#if !BUILDFLAG(IS_ANDROID)
// Same as CanUseBackgroundThreadTypeForWorkerThreadImpl()
if (!PlatformThread::CanChangeThreadType(ThreadType::kUtility,
ThreadType::kDefault))
return false;
#endif // BUILDFLAG(IS_ANDROID)
return true;
}
} // namespace
bool CanUseBackgroundThreadTypeForWorkerThread() {
static const bool can_use_background_thread_type_for_worker_thread =
CanUseBackgroundThreadTypeForWorkerThreadImpl();
return can_use_background_thread_type_for_worker_thread;
}
bool CanUseUtilityThreadTypeForWorkerThread() {
static const bool can_use_utility_thread_type_for_worker_thread =
CanUseUtilityThreadTypeForWorkerThreadImpl();
return can_use_utility_thread_type_for_worker_thread;
}
} // namespace internal
} // namespace base