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
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
|
// Copyright 2014 Citra Emulator Project
// Licensed under GPLv2
// Refer to the license.txt file included.
#include <map>
#include <vector>
#include "common/common.h"
#include "core/hle/kernel/kernel.h"
#include "core/hle/kernel/mutex.h"
#include "core/hle/kernel/thread.h"
namespace Kernel {
class Mutex : public Object {
public:
std::string GetTypeName() const override { return "Mutex"; }
std::string GetName() const override { return name; }
static Kernel::HandleType GetStaticHandleType() { return Kernel::HandleType::Mutex; }
Kernel::HandleType GetHandleType() const override { return Kernel::HandleType::Mutex; }
bool initial_locked; ///< Initial lock state when mutex was created
bool locked; ///< Current locked state
Handle lock_thread; ///< Handle to thread that currently has mutex
std::vector<Handle> waiting_threads; ///< Threads that are waiting for the mutex
std::string name; ///< Name of mutex (optional)
ResultVal<bool> WaitSynchronization() override;
};
////////////////////////////////////////////////////////////////////////////////////////////////////
typedef std::multimap<Handle, Handle> MutexMap;
static MutexMap g_mutex_held_locks;
/**
* Acquires the specified mutex for the specified thread
* @param mutex Mutex that is to be acquired
* @param thread Thread that will acquired
*/
void MutexAcquireLock(Mutex* mutex, Handle thread = GetCurrentThreadHandle()) {
g_mutex_held_locks.insert(std::make_pair(thread, mutex->GetHandle()));
mutex->lock_thread = thread;
}
bool ReleaseMutexForThread(Mutex* mutex, Handle thread) {
MutexAcquireLock(mutex, thread);
Kernel::ResumeThreadFromWait(thread);
return true;
}
/**
* Resumes a thread waiting for the specified mutex
* @param mutex The mutex that some thread is waiting on
*/
void ResumeWaitingThread(Mutex* mutex) {
// Find the next waiting thread for the mutex...
if (mutex->waiting_threads.empty()) {
// Reset mutex lock thread handle, nothing is waiting
mutex->locked = false;
mutex->lock_thread = -1;
}
else {
// Resume the next waiting thread and re-lock the mutex
std::vector<Handle>::iterator iter = mutex->waiting_threads.begin();
ReleaseMutexForThread(mutex, *iter);
mutex->waiting_threads.erase(iter);
}
}
void MutexEraseLock(Mutex* mutex) {
Handle handle = mutex->GetHandle();
auto locked = g_mutex_held_locks.equal_range(mutex->lock_thread);
for (MutexMap::iterator iter = locked.first; iter != locked.second; ++iter) {
if (iter->second == handle) {
g_mutex_held_locks.erase(iter);
break;
}
}
mutex->lock_thread = -1;
}
void ReleaseThreadMutexes(Handle thread) {
auto locked = g_mutex_held_locks.equal_range(thread);
// Release every mutex that the thread holds, and resume execution on the waiting threads
for (MutexMap::iterator iter = locked.first; iter != locked.second; ++iter) {
Mutex* mutex = g_object_pool.GetFast<Mutex>(iter->second);
ResumeWaitingThread(mutex);
}
// Erase all the locks that this thread holds
g_mutex_held_locks.erase(thread);
}
bool LockMutex(Mutex* mutex) {
// Mutex alread locked?
if (mutex->locked) {
return false;
}
MutexAcquireLock(mutex);
return true;
}
bool ReleaseMutex(Mutex* mutex) {
MutexEraseLock(mutex);
ResumeWaitingThread(mutex);
return true;
}
/**
* Releases a mutex
* @param handle Handle to mutex to release
*/
ResultCode ReleaseMutex(Handle handle) {
Mutex* mutex = Kernel::g_object_pool.Get<Mutex>(handle);
if (mutex == nullptr) return InvalidHandle(ErrorModule::Kernel);
if (!ReleaseMutex(mutex)) {
// TODO(yuriks): Verify error code, this one was pulled out of thin air. I'm not even sure
// what error condition this is supposed to be signaling.
return ResultCode(ErrorDescription::AlreadyDone, ErrorModule::Kernel,
ErrorSummary::NothingHappened, ErrorLevel::Temporary);
}
return RESULT_SUCCESS;
}
/**
* Creates a mutex
* @param handle Reference to handle for the newly created mutex
* @param initial_locked Specifies if the mutex should be locked initially
* @param name Optional name of mutex
* @return Pointer to new Mutex object
*/
Mutex* CreateMutex(Handle& handle, bool initial_locked, const std::string& name) {
Mutex* mutex = new Mutex;
handle = Kernel::g_object_pool.Create(mutex);
mutex->locked = mutex->initial_locked = initial_locked;
mutex->name = name;
// Acquire mutex with current thread if initialized as locked...
if (mutex->locked) {
MutexAcquireLock(mutex);
// Otherwise, reset lock thread handle
} else {
mutex->lock_thread = -1;
}
return mutex;
}
/**
* Creates a mutex
* @param initial_locked Specifies if the mutex should be locked initially
* @param name Optional name of mutex
* @return Handle to newly created object
*/
Handle CreateMutex(bool initial_locked, const std::string& name) {
Handle handle;
Mutex* mutex = CreateMutex(handle, initial_locked, name);
return handle;
}
ResultVal<bool> Mutex::WaitSynchronization() {
bool wait = locked;
if (locked) {
Kernel::WaitCurrentThread(WAITTYPE_MUTEX, GetHandle());
}
else {
// Lock the mutex when the first thread accesses it
locked = true;
MutexAcquireLock(this);
}
return MakeResult<bool>(wait);
}
} // namespace
|
