1
    2
    3
    4
    5
    6
    7
    8
    9
   10
   11
   12
   13
   14
   15
   16
   17
   18
   19
   20
   21
   22
   23
   24
   25
   26
   27
   28
   29
   30
   31
   32
   33
   34
   35
   36
   37
   38
   39
   40
   41
   42
   43
   44
   45
   46
   47
   48
   49
   50
   51
   52
   53
   54
   55
   56
   57
   58
   59
   60
   61
   62
   63
   64
   65
   66
   67
   68
   69
   70
   71
   72
   73
   74
   75

base / task / task_features.cc [blame]

// Copyright 2018 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/task_features.h"

#include <atomic>

#include "base/base_export.h"
#include "base/feature_list.h"
#include "build/build_config.h"

namespace base {

// Note to implementers: thread pool code using task features must absolutely
// not invoke FeatureList::IsEnabled outside of the main thread. Doing so
// causes data races between worker threads and ~FeatureList when tests end
// (crbug.com/1344573). A reliable moment to query and cache the feature state
// is on ThreadPoolImpl::Start (and thus also on the first WorkerThread::Start,
// not the later ones) as this is invoked from the main thread after
// initializing the FeatureList. If caching the feature state in a static, you
// must be aware that all tests sharing a process will have the same state,
// regardless of future ScopedFeatureList instances.

BASE_FEATURE(kUseUtilityThreadGroup,
             "UseUtilityThreadGroup",
             base::FEATURE_DISABLED_BY_DEFAULT);

BASE_FEATURE(kDelayFirstWorkerWake,
             "DelayFirstWorkerWake",
             base::FEATURE_ENABLED_BY_DEFAULT);

BASE_FEATURE(kAddTaskLeewayFeature,
             "AddTaskLeeway",
             base::FEATURE_ENABLED_BY_DEFAULT);

const base::FeatureParam<TimeDelta> kTaskLeewayParam{&kAddTaskLeewayFeature,
                                                     "leeway", kDefaultLeeway};
const base::FeatureParam<TimeDelta> kMaxPreciseDelay{
    &kAddTaskLeewayFeature, "max_precise_delay", kDefaultMaxPreciseDelay};

BASE_FEATURE(kAlignWakeUps, "AlignWakeUps", base::FEATURE_DISABLED_BY_DEFAULT);

BASE_FEATURE(kTimerSlackMac,
             "TimerSlackMac",
             base::FEATURE_DISABLED_BY_DEFAULT);

BASE_FEATURE(kExplicitHighResolutionTimerWin,
             "ExplicitHighResolutionTimerWin",
             base::FEATURE_ENABLED_BY_DEFAULT);

BASE_FEATURE(kUIPumpImprovementsWin,
             "UIPumpImprovementsWin",
             base::FEATURE_ENABLED_BY_DEFAULT);

BASE_FEATURE(kPumpFastToSleepAndroid,
             "PumpFastToSleepAndroid",
             base::FEATURE_ENABLED_BY_DEFAULT);

BASE_FEATURE(kRunTasksByBatches,
             "RunTasksByBatches",
#if BUILDFLAG(IS_MAC) || BUILDFLAG(IS_CHROMEOS) || BUILDFLAG(IS_WIN)
             base::FEATURE_ENABLED_BY_DEFAULT);
#else
             base::FEATURE_DISABLED_BY_DEFAULT);
#endif

BASE_FEATURE(kThreadPoolCap2,
             "ThreadPoolCap2",
             base::FEATURE_DISABLED_BY_DEFAULT);

const base::FeatureParam<int> kThreadPoolCapRestrictedCount{
    &kThreadPoolCap2, "restricted_count", 3};

}  // namespace base