1/*
2 * Copyright (C) 2017 Yusuke Suzuki <utatane.tea@gmail.com>.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#pragma once
27
28#include <wtf/AutomaticThread.h>
29#include <wtf/Deque.h>
30#include <wtf/Function.h>
31#include <wtf/NumberOfCores.h>
32#include <wtf/Vector.h>
33#include <wtf/text/WTFString.h>
34
35namespace WTF {
36
37class WorkerPool : public ThreadSafeRefCounted<WorkerPool> {
38public:
39 WTF_EXPORT_PRIVATE void postTask(Function<void()>&&);
40
41 WTF_EXPORT_PRIVATE ~WorkerPool();
42
43 // If timeout is infinity, it means AutomaticThread will be never automatically destroyed.
44 static Ref<WorkerPool> create(ASCIILiteral name, unsigned numberOfWorkers = WTF::numberOfProcessorCores(), Seconds timeout = Seconds::infinity())
45 {
46 ASSERT(numberOfWorkers >= 1);
47 return adoptRef(*new WorkerPool(name, numberOfWorkers, timeout));
48 }
49
50 ASCIILiteral name() const { return m_name; }
51
52private:
53 class Worker;
54 friend class Worker;
55
56 WTF_EXPORT_PRIVATE WorkerPool(ASCIILiteral name, unsigned numberOfWorkers, Seconds timeout);
57
58 bool shouldSleep(const AbstractLocker&);
59
60 Box<Lock> m_lock;
61 Ref<AutomaticThreadCondition> m_condition;
62 Seconds m_timeout;
63 MonotonicTime m_lastTimeoutTime { MonotonicTime::nan() };
64 unsigned m_numberOfActiveWorkers { 0 };
65 Vector<Ref<Worker>> m_workers;
66 Deque<Function<void()>> m_tasks;
67 ASCIILiteral m_name;
68};
69
70}
71
72using WTF::WorkerPool;
73