[HLE] Remove ServerBase 1ms polling (#5855)

Added a KEvent for each ServerBase which signals whenever a session is added to the _sessions list, which allows it to rerun the ReplyAndReceive with the new session handle.

This greatly reduces the presence of ServerBase on profiles, especially of games that aren't particularly busy. It should also increase responsiveness when adding session objects, as it doesn't take at most 1ms for them to start working.

It also reduces the load on KTimeManager, which could allow it to spin less often. I have noticed that a bunch of games still do 1ms waits (they actually request a bit less than 1ms), so they still end up spinning to the next millisecond. Maybe for waits like this, it could attempt to nudge the timepoints to snap to each other when they're close enough, and also snap to whole millisecond waits when close enough.

src/Ryujinx.Graphics.Gpu/Image/Texture.cs

@@ -101,6 +101,11 @@ namespace Ryujinx.Graphics.Gpu.Image
         /// </summary>
         public bool AlwaysFlushOnOverlap { get; private set; }
 
+        /// <summary>
+        /// Indicates that the texture was fully unmapped since the modified flag was set, and flushes should be ignored until it is modified again.
+        /// </summary>
+        public bool FlushStale { get; private set; }
+
         /// <summary>
         /// Increments when the host texture is swapped, or when the texture is removed from all pools.
         /// </summary>
@@ -149,6 +154,7 @@ namespace Ryujinx.Graphics.Gpu.Image
         /// </summary>
         public bool HadPoolOwner { get; private set; }
 
+        /// <summary>
         /// Physical memory ranges where the texture data is located.
         /// </summary>
         public MultiRange Range { get; private set; }
@@ -1411,6 +1417,7 @@ namespace Ryujinx.Graphics.Gpu.Image
         /// </summary>
         public void SignalModified()
         {
+            FlushStale = false;
             _scaledSetScore = Math.Max(0, _scaledSetScore - 1);
 
             if (_modifiedStale || Group.HasCopyDependencies)
@@ -1431,6 +1438,7 @@ namespace Ryujinx.Graphics.Gpu.Image
         {
             if (bound)
             {
+                FlushStale = false;
                 _scaledSetScore = Math.Max(0, _scaledSetScore - 1);
             }
 
@@ -1695,12 +1703,17 @@ namespace Ryujinx.Graphics.Gpu.Image
         /// <param name="unmapRange">The range of memory being unmapped</param>
         public void Unmapped(MultiRange unmapRange)
         {
+            if (unmapRange.Contains(Range))
+            {
+                // If this is a full unmap, prevent flushes until the texture is mapped again.
+                FlushStale = true;
+            }
+
             ChangedMapping = true;
 
             if (Group.Storage == this)
             {
                 Group.Unmapped();
-
                 Group.ClearModified(unmapRange);
             }
         }

src/Ryujinx.Graphics.Gpu/Image/TextureCache.cs

@@ -107,8 +107,6 @@ namespace Ryujinx.Graphics.Gpu.Image
                             // Any texture that has been unmapped at any point or is partially unmapped
                             // should update their pool references after the remap completes.
 
-                            MultiRange unmapped = ((MemoryManager)sender).GetPhysicalRegions(e.Address, e.Size);
-
                             foreach (var texture in _partiallyMappedTextures)
                             {
                                 texture.UpdatePoolMappings();

src/Ryujinx.Graphics.Gpu/Image/TextureGroup.cs

@@ -1659,6 +1659,14 @@ namespace Ryujinx.Graphics.Gpu.Image
                 return;
             }
 
+            // If size is zero, we have nothing to flush.
+            // If the flush is stale, we should ignore it because the texture was unmapped since the modified
+            // flag was set, and flushing it is not safe anymore as the GPU might no longer own the memory.
+            if (size == 0 || Storage.FlushStale)
+            {
+                return;
+            }
+
             // There is a small gap here where the action is removed but _actionRegistered is still 1.
             // In this case it will skip registering the action, but here we are already handling it,
             // so there shouldn't be any issue as it's the same handler for all actions.

src/Ryujinx.HLE/HOS/Services/ServerBase.cs

@@ -39,6 +39,8 @@ namespace Ryujinx.HLE.HOS.Services
         private readonly KernelContext _context;
         private KProcess _selfProcess;
         private KThread _selfThread;
+        private KEvent _wakeEvent;
+        private int _wakeHandle = 0;
 
         private readonly ReaderWriterLockSlim _handleLock = new();
         private readonly Dictionary<int, IpcService> _sessions = new();
@@ -125,6 +127,8 @@ namespace Ryujinx.HLE.HOS.Services
                     _handleLock.ExitWriteLock();
                 }
             }
+
+            _wakeEvent.WritableEvent.Signal();
         }
 
         private IpcService GetSessionObj(int serverSessionHandle)
@@ -195,9 +199,11 @@ namespace Ryujinx.HLE.HOS.Services
             _selfProcess.CpuMemory.Write(messagePtr + 0x0, 0);
             _selfProcess.CpuMemory.Write(messagePtr + 0x4, 2 << 10);
             _selfProcess.CpuMemory.Write(messagePtr + 0x8, heapAddr | ((ulong)PointerBufferSize << 48));
-
             int replyTargetHandle = 0;
 
+            _wakeEvent = new KEvent(_context);
+            Result result = _selfProcess.HandleTable.GenerateHandle(_wakeEvent.ReadableEvent, out _wakeHandle);
+
             while (true)
             {
                 int portHandleCount;
@@ -211,13 +217,15 @@ namespace Ryujinx.HLE.HOS.Services
 
                     portHandleCount = _ports.Count;
 
-                    handleCount = portHandleCount + _sessions.Count;
+                    handleCount = portHandleCount + _sessions.Count + 1;
 
                     handles = ArrayPool<int>.Shared.Rent(handleCount);
 
-                    _ports.Keys.CopyTo(handles, 0);
+                    handles[0] = _wakeHandle;
 
-                    _sessions.Keys.CopyTo(handles, portHandleCount);
+                    _ports.Keys.CopyTo(handles, 1);
+
+                    _sessions.Keys.CopyTo(handles, portHandleCount + 1);
                 }
                 finally
                 {
@@ -227,8 +235,7 @@ namespace Ryujinx.HLE.HOS.Services
                     }
                 }
 
-                // We still need a timeout here to allow the service to pick up and listen new sessions...
-                var rc = _context.Syscall.ReplyAndReceive(out int signaledIndex, handles.AsSpan(0, handleCount), replyTargetHandle, 1000000L);
+                var rc = _context.Syscall.ReplyAndReceive(out int signaledIndex, handles.AsSpan(0, handleCount), replyTargetHandle, -1);
 
                 _selfThread.HandlePostSyscall();
 
@@ -239,7 +246,7 @@ namespace Ryujinx.HLE.HOS.Services
 
                 replyTargetHandle = 0;
 
-                if (rc == Result.Success && signaledIndex >= portHandleCount)
+                if (rc == Result.Success && signaledIndex >= portHandleCount + 1)
                 {
                     // We got a IPC request, process it, pass to the appropriate service if needed.
                     int signaledHandle = handles[signaledIndex];
@@ -253,24 +260,32 @@ namespace Ryujinx.HLE.HOS.Services
                 {
                     if (rc == Result.Success)
                     {
-                        // We got a new connection, accept the session to allow servicing future requests.
-                        if (_context.Syscall.AcceptSession(out int serverSessionHandle, handles[signaledIndex]) == Result.Success)
+                        if (signaledIndex > 0)
                         {
-                            bool handleWriteLockTaken = false;
-                            try
+                            // We got a new connection, accept the session to allow servicing future requests.
+                            if (_context.Syscall.AcceptSession(out int serverSessionHandle, handles[signaledIndex]) == Result.Success)
                             {
-                                handleWriteLockTaken = _handleLock.TryEnterWriteLock(Timeout.Infinite);
-                                IpcService obj = _ports[handles[signaledIndex]].Invoke();
-                                _sessions.Add(serverSessionHandle, obj);
-                            }
-                            finally
-                            {
-                                if (handleWriteLockTaken)
+                                bool handleWriteLockTaken = false;
+                                try
                                 {
-                                    _handleLock.ExitWriteLock();
+                                    handleWriteLockTaken = _handleLock.TryEnterWriteLock(Timeout.Infinite);
+                                    IpcService obj = _ports[handles[signaledIndex]].Invoke();
+                                    _sessions.Add(serverSessionHandle, obj);
+                                }
+                                finally
+                                {
+                                    if (handleWriteLockTaken)
+                                    {
+                                        _handleLock.ExitWriteLock();
+                                    }
                                 }
                             }
                         }
+                        else
+                        {
+                            // The _wakeEvent signalled, which means we have a new session.
+                            _wakeEvent.WritableEvent.Clear();
+                        }
                     }
 
                     _selfProcess.CpuMemory.Write(messagePtr + 0x0, 0);
@@ -499,6 +514,8 @@ namespace Ryujinx.HLE.HOS.Services
 
                 if (Interlocked.Exchange(ref _isDisposed, 1) == 0)
                 {
+                    _selfProcess.HandleTable.CloseHandle(_wakeHandle);
+
                     foreach (IpcService service in _sessions.Values)
                     {
                         (service as IDisposable)?.Dispose();