src/Ryujinx.HLE/HOS/Kernel/Threading/KSynchronization.cs


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

using Ryujinx.HLE.HOS.Kernel.Common;
using Ryujinx.Horizon.Common;
using System;
using System.Buffers;
using System.Collections.Generic;

namespace Ryujinx.HLE.HOS.Kernel.Threading
{
    class KSynchronization
    {
        private KernelContext _context;

        public KSynchronization(KernelContext context)
        {
            _context = context;
        }

        public Result WaitFor(Span<KSynchronizationObject> syncObjs, long timeout, out int handleIndex)
        {
            handleIndex = 0;

            Result result = KernelResult.TimedOut;

            _context.CriticalSection.Enter();

            // Check if objects are already signaled before waiting.
            for (int index = 0; index < syncObjs.Length; index++)
            {
                if (!syncObjs[index].IsSignaled())
                {
                    continue;
                }

                handleIndex = index;

                _context.CriticalSection.Leave();

                return Result.Success;
            }

            if (timeout == 0)
            {
                _context.CriticalSection.Leave();

                return result;
            }

            KThread currentThread = KernelStatic.GetCurrentThread();

            if (currentThread.TerminationRequested)
            {
                result = KernelResult.ThreadTerminating;
            }
            else if (currentThread.SyncCancelled)
            {
                currentThread.SyncCancelled = false;

                result = KernelResult.Cancelled;
            }
            else
            {
                LinkedListNode<KThread>[] syncNodesArray = ArrayPool<LinkedListNode<KThread>>.Shared.Rent(syncObjs.Length);

                Span<LinkedListNode<KThread>> syncNodes = syncNodesArray.AsSpan(0, syncObjs.Length);

                for (int index = 0; index < syncObjs.Length; index++)
                {
                    syncNodes[index] = syncObjs[index].AddWaitingThread(currentThread);
                }

                currentThread.WaitingSync   = true;
                currentThread.SignaledObj   = null;
                currentThread.ObjSyncResult = result;

                currentThread.Reschedule(ThreadSchedState.Paused);

                if (timeout > 0)
                {
                    _context.TimeManager.ScheduleFutureInvocation(currentThread, timeout);
                }

                _context.CriticalSection.Leave();

                currentThread.WaitingSync = false;

                if (timeout > 0)
                {
                    _context.TimeManager.UnscheduleFutureInvocation(currentThread);
                }

                _context.CriticalSection.Enter();

                result = currentThread.ObjSyncResult;

                handleIndex = -1;

                for (int index = 0; index < syncObjs.Length; index++)
                {
                    syncObjs[index].RemoveWaitingThread(syncNodes[index]);

                    if (syncObjs[index] == currentThread.SignaledObj)
                    {
                        handleIndex = index;
                    }
                }

                ArrayPool<LinkedListNode<KThread>>.Shared.Return(syncNodesArray);
            }

            _context.CriticalSection.Leave();

            return result;
        }

        public void SignalObject(KSynchronizationObject syncObj)
        {
            _context.CriticalSection.Enter();

            if (syncObj.IsSignaled())
            {
                LinkedListNode<KThread> node = syncObj.WaitingThreads.First;

                while (node != null)
                {
                    KThread thread = node.Value;

                    if ((thread.SchedFlags & ThreadSchedState.LowMask) == ThreadSchedState.Paused)
                    {
                        thread.SignaledObj   = syncObj;
                        thread.ObjSyncResult = Result.Success;

                        thread.Reschedule(ThreadSchedState.Running);
                    }

                    node = node.Next;
                }
            }

            _context.CriticalSection.Leave();
        }
    }
}