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
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
|
/*
* Copyright (C) 2014 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO , PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
* THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "config.h"
#include "ProcessThrottler.h"
#include "ProcessThrottlerClient.h"
namespace WebKit {
static const unsigned processSuspensionTimeout = 30;
ProcessThrottler::ProcessThrottler(ProcessThrottlerClient& process)
: m_process(process)
, m_suspendTimer(RunLoop::main(), this, &ProcessThrottler::suspendTimerFired)
, m_foregroundCounter([this](bool) { updateAssertion(); })
, m_backgroundCounter([this](bool) { updateAssertion(); })
, m_suspendMessageCount(0)
{
}
AssertionState ProcessThrottler::assertionState()
{
ASSERT(!m_suspendTimer.isActive());
if (m_foregroundCounter.value())
return AssertionState::Foreground;
if (m_backgroundCounter.value())
return AssertionState::Background;
return AssertionState::Suspended;
}
void ProcessThrottler::updateAssertionNow()
{
m_suspendTimer.stop();
if (m_assertion) {
m_assertion->setState(assertionState());
m_process.didSetAssertionState(assertionState());
}
}
void ProcessThrottler::updateAssertion()
{
// If the process is currently runnable but will be suspended then first give it a chance to complete what it was doing
// and clean up - move it to the background and send it a message to notify. Schedule a timeout so it can't stay running
// in the background for too long.
if (m_assertion && m_assertion->state() != AssertionState::Suspended && !m_foregroundCounter.value() && !m_backgroundCounter.value()) {
++m_suspendMessageCount;
m_process.sendPrepareToSuspend();
m_suspendTimer.startOneShot(processSuspensionTimeout);
m_assertion->setState(AssertionState::Background);
m_process.didSetAssertionState(AssertionState::Background);
return;
}
bool shouldBeRunnable = m_foregroundCounter.value() || m_backgroundCounter.value();
// If we're currently waiting for the Web process to do suspension cleanup, but no longer need to be suspended, tell the Web process to cancel the cleanup.
if (m_suspendTimer.isActive() && shouldBeRunnable)
m_process.sendCancelPrepareToSuspend();
if (m_assertion && m_assertion->state() == AssertionState::Suspended && shouldBeRunnable)
m_process.sendProcessDidResume();
updateAssertionNow();
}
void ProcessThrottler::didConnectToProcess(PlatformProcessIdentifier pid)
{
m_suspendTimer.stop();
m_assertion = std::make_unique<ProcessAndUIAssertion>(pid, assertionState());
m_process.didSetAssertionState(assertionState());
m_assertion->setClient(*this);
}
void ProcessThrottler::suspendTimerFired()
{
updateAssertionNow();
}
void ProcessThrottler::processReadyToSuspend()
{
if (!--m_suspendMessageCount)
updateAssertionNow();
ASSERT(m_suspendMessageCount >= 0);
}
void ProcessThrottler::didCancelProcessSuspension()
{
if (!--m_suspendMessageCount)
updateAssertionNow();
ASSERT(m_suspendMessageCount >= 0);
}
void ProcessThrottler::assertionWillExpireImminently()
{
m_process.sendProcessWillSuspendImminently();
}
}
|
