From 31b21b2d1765cc904d1deb9bda5d4d42b99dccd6 Mon Sep 17 00:00:00 2001
From: "Steve MacLean, Qualcomm Datacenter Technologies Inc"
 <sdmaclea@qti.qualcomm.com>
Date: Fri, 28 Jul 2017 12:44:43 -0400
Subject: [PATCH] mscorlib cache padding for 128 byte lines

---
 .../src/System/Collections/Concurrent/ConcurrentQueue.cs    | 6 +++---
 .../src/System/Threading/Tasks/ProducerConsumerQueues.cs    | 2 +-
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/mscorlib/src/System/Collections/Concurrent/ConcurrentQueue.cs b/src/mscorlib/src/System/Collections/Concurrent/ConcurrentQueue.cs
index 632f0eecef9e..ad08019b669a 100644
--- a/src/mscorlib/src/System/Collections/Concurrent/ConcurrentQueue.cs
+++ b/src/mscorlib/src/System/Collections/Concurrent/ConcurrentQueue.cs
@@ -1111,10 +1111,10 @@ internal struct Slot
 
     /// <summary>Padded head and tail indices, to avoid false sharing between producers and consumers.</summary>
     [DebuggerDisplay("Head = {Head}, Tail = {Tail}")]
-    [StructLayout(LayoutKind.Explicit, Size = 192)] // padding before/between/after fields based on typical cache line size of 64
+    [StructLayout(LayoutKind.Explicit, Size = 384)] // padding before/between/after fields based on worst case cache line size of 128
     internal struct PaddedHeadAndTail
     {
-        [FieldOffset(64)] public int Head;
-        [FieldOffset(128)] public int Tail;
+        [FieldOffset(128)] public int Head;
+        [FieldOffset(256)] public int Tail;
     }
 }
diff --git a/src/mscorlib/src/System/Threading/Tasks/ProducerConsumerQueues.cs b/src/mscorlib/src/System/Threading/Tasks/ProducerConsumerQueues.cs
index f9d5f89398bb..beed1b4e882a 100644
--- a/src/mscorlib/src/System/Threading/Tasks/ProducerConsumerQueues.cs
+++ b/src/mscorlib/src/System/Threading/Tasks/ProducerConsumerQueues.cs
@@ -375,7 +375,7 @@ internal static class PaddingHelpers
     }
 
     /// <summary>Padding structure used to minimize false sharing in SingleProducerSingleConsumerQueue{T}.</summary>
-    [StructLayout(LayoutKind.Explicit, Size = PaddingHelpers.CACHE_LINE_SIZE - sizeof(Int32))] // Based on common case of 64-byte cache lines
+    [StructLayout(LayoutKind.Explicit, Size = PaddingHelpers.CACHE_LINE_SIZE - sizeof(Int32))]
     internal struct PaddingFor32
     {
     }