Timing: Optimize Timestamp Aquisition (#479)

* Timing: Optimize Timestamp Aquisition

Currently, we make use of Environment.TickCount in a number of places. This has some downsides, mainly being that the TickCount is a signed 32-bit integer, and has an effective limit of ~25 days before overflowing and wrapping around. Due to the signed-ness of the value, this also caused issues with negative numbers. This resolves these issues by using a 64-bit tick count obtained from Performance Counters (via the Stopwatch class). This has a beneficial side effect of being significantly more accurate than the TickCount.

* Timing: Rename ElapsedTicks to ElapsedMilliseconds and expose TicksPerX

* Timing: Some style changes

* Timing: Align static variable initialization

2 files changed, 7 insertions, 17 deletions

diff --git a/Ryujinx.Graphics/Gal/OpenGL/OGLCachedResource.cs b/Ryujinx.Graphics/Gal/OpenGL/OGLCachedResource.cs
index 839915ea..a65ebcbb 100644
--- a/Ryujinx.Graphics/Gal/OpenGL/OGLCachedResource.cs
+++ b/Ryujinx.Graphics/Gal/OpenGL/OGLCachedResource.cs
@@ -1,3 +1,4 @@
+using Ryujinx.Common;
 using System;
 using System.Collections.Generic;
 
@@ -18,7 +19,7 @@ namespace Ryujinx.Graphics.Gal.OpenGL
 
             public long DataSize { get; private set; }
 
-            public int Timestamp { get; private set; }
+            public long Timestamp { get; private set; }
 
             public CacheBucket(T Value, long DataSize, LinkedListNode<long> Node)
             {
@@ -26,7 +27,7 @@ namespace Ryujinx.Graphics.Gal.OpenGL
                 this.DataSize = DataSize;
                 this.Node     = Node;
 
-                Timestamp = Environment.TickCount;
+                Timestamp = PerformanceCounter.ElapsedMilliseconds;
             }
         }
 
@@ -141,7 +142,7 @@ namespace Ryujinx.Graphics.Gal.OpenGL
 
         private void ClearCacheIfNeeded()
         {
-            int Timestamp = Environment.TickCount;
+            long Timestamp = PerformanceCounter.ElapsedMilliseconds;
 
             int Count = 0;
 
@@ -156,7 +157,7 @@ namespace Ryujinx.Graphics.Gal.OpenGL
 
                 CacheBucket Bucket = Cache[Node.Value];
 
-                int TimeDelta = RingDelta(Bucket.Timestamp, Timestamp);
+                long TimeDelta = Bucket.Timestamp - Timestamp;
 
                 if ((uint)TimeDelta <= (uint)MaxTimeDelta)
                 {
@@ -170,17 +171,5 @@ namespace Ryujinx.Graphics.Gal.OpenGL
                 DeleteValueCallback(Bucket.Value);
             }
         }
-
-        private int RingDelta(int Old, int New)
-        {
-            if ((uint)New < (uint)Old)
-            {
-                return New + (~Old + 1);
-            }
-            else
-            {
-                return New - Old;
-            }
-        }
     }
 }
\ No newline at end of file
diff --git a/Ryujinx.Graphics/NvGpuEngine3d.cs b/Ryujinx.Graphics/NvGpuEngine3d.cs
index 7d2b2b43..618d7d9f 100644
--- a/Ryujinx.Graphics/NvGpuEngine3d.cs
+++ b/Ryujinx.Graphics/NvGpuEngine3d.cs
@@ -1,3 +1,4 @@
+using Ryujinx.Common;
 using Ryujinx.Graphics.Gal;
 using Ryujinx.Graphics.Memory;
 using Ryujinx.Graphics.Texture;
@@ -851,7 +852,7 @@ namespace Ryujinx.Graphics
                     //TODO: Implement counters.
                     long Counter = 1;
 
-                    long Timestamp = (uint)Environment.TickCount;
+                    long Timestamp = PerformanceCounter.ElapsedMilliseconds;
 
                     Timestamp = (long)(Timestamp * 615384.615385);