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
|
// Copyright 2018 yuzu emulator team
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#include "core/core.h"
#include "core/core_timing.h"
#include "core/hle/kernel/process.h"
#include "core/hle/kernel/scheduler.h"
namespace Kernel {
std::mutex Scheduler::scheduler_mutex;
Scheduler::Scheduler(ARM_Interface* cpu_core) : cpu_core(cpu_core) {}
Scheduler::~Scheduler() {
for (auto& thread : thread_list) {
thread->Stop();
}
}
bool Scheduler::HaveReadyThreads() {
std::lock_guard<std::mutex> lock(scheduler_mutex);
return ready_queue.get_first() != nullptr;
}
Thread* Scheduler::GetCurrentThread() const {
return current_thread.get();
}
Thread* Scheduler::PopNextReadyThread() {
Thread* next = nullptr;
Thread* thread = GetCurrentThread();
if (thread && thread->status == THREADSTATUS_RUNNING) {
// We have to do better than the current thread.
// This call returns null when that's not possible.
next = ready_queue.pop_first_better(thread->current_priority);
if (!next) {
// Otherwise just keep going with the current thread
next = thread;
}
} else {
next = ready_queue.pop_first();
}
return next;
}
void Scheduler::SwitchContext(Thread* new_thread) {
Thread* previous_thread = GetCurrentThread();
// Save context for previous thread
if (previous_thread) {
previous_thread->last_running_ticks = CoreTiming::GetTicks();
cpu_core->SaveContext(previous_thread->context);
if (previous_thread->status == THREADSTATUS_RUNNING) {
// This is only the case when a reschedule is triggered without the current thread
// yielding execution (i.e. an event triggered, system core time-sliced, etc)
ready_queue.push_front(previous_thread->current_priority, previous_thread);
previous_thread->status = THREADSTATUS_READY;
}
}
// Load context of new thread
if (new_thread) {
ASSERT_MSG(new_thread->status == THREADSTATUS_READY,
"Thread must be ready to become running.");
// Cancel any outstanding wakeup events for this thread
new_thread->CancelWakeupTimer();
auto previous_process = Core::CurrentProcess();
current_thread = new_thread;
ready_queue.remove(new_thread->current_priority, new_thread);
new_thread->status = THREADSTATUS_RUNNING;
if (previous_process != current_thread->owner_process) {
Core::CurrentProcess() = current_thread->owner_process;
SetCurrentPageTable(&Core::CurrentProcess()->vm_manager.page_table);
}
cpu_core->LoadContext(new_thread->context);
cpu_core->SetTlsAddress(new_thread->GetTLSAddress());
} else {
current_thread = nullptr;
// Note: We do not reset the current process and current page table when idling because
// technically we haven't changed processes, our threads are just paused.
}
}
void Scheduler::Reschedule() {
std::lock_guard<std::mutex> lock(scheduler_mutex);
Thread* cur = GetCurrentThread();
Thread* next = PopNextReadyThread();
if (cur && next) {
LOG_TRACE(Kernel, "context switch {} -> {}", cur->GetObjectId(), next->GetObjectId());
} else if (cur) {
LOG_TRACE(Kernel, "context switch {} -> idle", cur->GetObjectId());
} else if (next) {
LOG_TRACE(Kernel, "context switch idle -> {}", next->GetObjectId());
}
SwitchContext(next);
}
void Scheduler::AddThread(SharedPtr<Thread> thread, u32 priority) {
std::lock_guard<std::mutex> lock(scheduler_mutex);
thread_list.push_back(thread);
ready_queue.prepare(priority);
}
void Scheduler::RemoveThread(Thread* thread) {
std::lock_guard<std::mutex> lock(scheduler_mutex);
thread_list.erase(std::remove(thread_list.begin(), thread_list.end(), thread),
thread_list.end());
}
void Scheduler::ScheduleThread(Thread* thread, u32 priority) {
std::lock_guard<std::mutex> lock(scheduler_mutex);
ASSERT(thread->status == THREADSTATUS_READY);
ready_queue.push_back(priority, thread);
}
void Scheduler::UnscheduleThread(Thread* thread, u32 priority) {
std::lock_guard<std::mutex> lock(scheduler_mutex);
ASSERT(thread->status == THREADSTATUS_READY);
ready_queue.remove(priority, thread);
}
void Scheduler::SetThreadPriority(Thread* thread, u32 priority) {
std::lock_guard<std::mutex> lock(scheduler_mutex);
// If thread was ready, adjust queues
if (thread->status == THREADSTATUS_READY)
ready_queue.move(thread, thread->current_priority, priority);
else
ready_queue.prepare(priority);
}
} // namespace Kernel
|
