From c4ec54e1cf75f177d6673bf0b3aec7c13464119a Mon Sep 17 00:00:00 2001
From: PhyxionNL <7643972+PhyxionNL@users.noreply.github.com>
Date: Mon, 7 Nov 2022 15:00:44 +0100
Subject: [PATCH] Thread affinity

Don't set thread affinity in IsValid.
Remove SetThreadAffinityMask fallback as SetThreadGroupAffinity is available in W7 and up.
---
 .../Hardware/ThreadAffinity.cs                | 45 +++++++------------
 LibreHardwareMonitorLib/Interop/Kernel32.cs   |  6 +--
 2 files changed, 18 insertions(+), 33 deletions(-)

diff --git a/LibreHardwareMonitorLib/Hardware/ThreadAffinity.cs b/LibreHardwareMonitorLib/Hardware/ThreadAffinity.cs
index 340af2c..eebe967 100644
--- a/LibreHardwareMonitorLib/Hardware/ThreadAffinity.cs
+++ b/LibreHardwareMonitorLib/Hardware/ThreadAffinity.cs
@@ -1,7 +1,7 @@
 // This Source Code Form is subject to the terms of the Mozilla Public License, v. 2.0.
 // If a copy of the MPL was not distributed with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
 // Copyright (C) LibreHardwareMonitor and Contributors.
-// Partial Copyright (C) Michael Möller <mmoeller@openhardwaremonitor.org> and Contributors.
+// Partial Copyright (C) Michael Möller <mmoeller@openhardwaremonitor.org> and Contributors.
 // All Rights Reserved.
 
 using System;
@@ -34,24 +34,25 @@ internal static class ThreadAffinity
     /// <returns><c>true</c> if the specified affinity is valid; otherwise, <c>false</c>.</returns>
     public static bool IsValid(GroupAffinity affinity)
     {
-        if (Software.OperatingSystem.IsUnix && affinity.Group > 0)
+        if (Software.OperatingSystem.IsUnix)
         {
-            return false;
-        }
-
-        try
-        {
-            GroupAffinity previousAffinity = Set(affinity);
-            if (previousAffinity == GroupAffinity.Undefined)
+            if (affinity.Group > 0)
                 return false;
 
-            Set(previousAffinity);
             return true;
         }
-        catch
+
+        UIntPtr uIntPtrMask;
+        try
+        {
+            uIntPtrMask = (UIntPtr)affinity.Mask;
+        }
+        catch (OverflowException)
         {
             return false;
         }
+
+        return true;
     }
 
     /// <summary>
@@ -94,25 +95,13 @@ internal static class ThreadAffinity
 
         IntPtr currentThread = Kernel32.GetCurrentThread();
 
-        try
+        if (Kernel32.SetThreadGroupAffinity(currentThread,
+                                            ref groupAffinity,
+                                            out Kernel32.GROUP_AFFINITY previousGroupAffinity))
         {
-            if (Kernel32.SetThreadGroupAffinity(currentThread,
-                                                ref groupAffinity,
-                                                out Kernel32.GROUP_AFFINITY previousGroupAffinity))
-            {
-                return new GroupAffinity(previousGroupAffinity.Group, (ulong)previousGroupAffinity.Mask);
-            }
-
-            return GroupAffinity.Undefined;
+            return new GroupAffinity(previousGroupAffinity.Group, (ulong)previousGroupAffinity.Mask);
         }
-        catch (EntryPointNotFoundException)
-        {
-            if (affinity.Group > 0)
-                throw new ArgumentOutOfRangeException(nameof(affinity));
 
-            ulong previous = (ulong)Kernel32.SetThreadAffinityMask(currentThread, uIntPtrMask);
-
-            return new GroupAffinity(0, previous);
-        }
+        return GroupAffinity.Undefined;
     }
 }
\ No newline at end of file
diff --git a/LibreHardwareMonitorLib/Interop/Kernel32.cs b/LibreHardwareMonitorLib/Interop/Kernel32.cs
index 64d2c38..5d9faba 100644
--- a/LibreHardwareMonitorLib/Interop/Kernel32.cs
+++ b/LibreHardwareMonitorLib/Interop/Kernel32.cs
@@ -317,10 +317,6 @@ public class Kernel32
     [return: MarshalAs(UnmanagedType.Bool)]
     internal static extern bool FreeLibrary(IntPtr module);
 
-    [DllImport(DllName, CallingConvention = CallingConvention.Winapi)]
-    [DefaultDllImportSearchPaths(DllImportSearchPath.System32)]
-    internal static extern UIntPtr SetThreadAffinityMask(IntPtr handle, UIntPtr mask);
-
     [DllImport(DllName, CallingConvention = CallingConvention.Winapi)]
     [DefaultDllImportSearchPaths(DllImportSearchPath.System32)]
     internal static extern IntPtr GetCurrentThread();
@@ -1558,4 +1554,4 @@ public class Kernel32
         FIRM = (byte)'F' << 24 | (byte)'I' << 16 | (byte)'R' << 8 | (byte)'M',
         RSMB = (byte)'R' << 24 | (byte)'S' << 16 | (byte)'M' << 8 | (byte)'B'
     }
-}
\ No newline at end of file
+}