1/*
2 * Copyright (C) 2017 Apple Inc. All rights reserved.
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/FastMalloc.h>
29#include <wtf/MonotonicTime.h>
30#include <wtf/Noncopyable.h>
31
32namespace JSC {
33
34class MutatorScheduler {
35 WTF_MAKE_NONCOPYABLE(MutatorScheduler);
36 WTF_MAKE_FAST_ALLOCATED;
37public:
38 enum State {
39 Normal, // Not collecting.
40 Stopped,
41 Resumed
42 };
43
44 MutatorScheduler();
45 virtual ~MutatorScheduler();
46
47 virtual State state() const = 0;
48
49 virtual void beginCollection() = 0;
50
51 virtual void didStop();
52 virtual void willResume();
53
54 // At the top of an iteration, the GC will may call didReachTermination.
55 virtual void didReachTermination();
56
57 // If it called didReachTermination, it will then later call didExecuteConstraints.
58 virtual void didExecuteConstraints();
59
60 // After doing that, it will do synchronous draining. When this stalls - either due to timeout or
61 // just 'cause, it will call this.
62 virtual void synchronousDrainingDidStall();
63
64 virtual MonotonicTime timeToStop() = 0; // Call while resumed, to ask when to stop.
65 virtual MonotonicTime timeToResume() = 0; // Call while stopped, to ask when to resume.
66
67 virtual void log();
68
69 bool shouldStop(); // Call while resumed, to ask if we should stop now.
70 bool shouldResume(); // Call while stopped, to ask if we should resume now.
71
72 virtual void endCollection() = 0;
73};
74
75} // namespace JSC
76
77