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
|
/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
* 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 THE COPYRIGHT HOLDERS AND 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 THE COPYRIGHT HOLDER OR 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.
*/
#pragma once
#include <AK/Assertions.h>
#include <AK/Atomic.h>
#include <AK/Types.h>
#include <Kernel/Arch/i386/CPU.h>
#include <Kernel/Forward.h>
#include <Kernel/WaitQueue.h>
namespace Kernel {
class Lock {
public:
Lock(const char* name = nullptr)
: m_name(name)
{
}
~Lock() {}
void lock();
void unlock();
bool force_unlock_if_locked();
bool is_locked() const { return m_holder; }
void clear_waiters();
const char* name() const { return m_name; }
private:
Atomic<bool> m_lock { false };
u32 m_level { 0 };
Thread* m_holder { nullptr };
const char* m_name { nullptr };
WaitQueue m_queue;
};
class Locker {
public:
[[gnu::always_inline]] inline explicit Locker(Lock& l)
: m_lock(l)
{
lock();
}
[[gnu::always_inline]] inline ~Locker() { unlock(); }
[[gnu::always_inline]] inline void unlock() { m_lock.unlock(); }
[[gnu::always_inline]] inline void lock() { m_lock.lock(); }
private:
Lock& m_lock;
};
#define LOCKER(lock) Locker locker(lock)
template<typename T>
class Lockable {
public:
Lockable() {}
Lockable(T&& resource)
: m_resource(move(resource))
{
}
Lock& lock() { return m_lock; }
T& resource() { return m_resource; }
T lock_and_copy()
{
LOCKER(m_lock);
return m_resource;
}
private:
T m_resource;
Lock m_lock;
};
}
|
