From 45e82d21f4e15234ce8b7cf39d005fa929f535c8 Mon Sep 17 00:00:00 2001
From: Wojtek Figat <wojtek@figat.pl>
Date: Thu, 26 Jun 2025 19:51:06 +0200
Subject: [PATCH] Fix `ConcurrentSystemLocker` to guard for a single writer at
 once

---
 Source/Engine/Threading/ConcurrentSystemLocker.cpp | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/Source/Engine/Threading/ConcurrentSystemLocker.cpp b/Source/Engine/Threading/ConcurrentSystemLocker.cpp
index f8eab96d9..c8debb561 100644
--- a/Source/Engine/Threading/ConcurrentSystemLocker.cpp
+++ b/Source/Engine/Threading/ConcurrentSystemLocker.cpp
@@ -22,6 +22,14 @@ RETRY:
         goto RETRY;
     }
 
+    // Writers have to check themselves to (one write at the same time - just like a mutex)
+    if (write && Platform::AtomicRead(thisCounter) != 0)
+    {
+        // Someone else is doing opposite operation so wait for it's end
+        Platform::Sleep(0);
+        goto RETRY;
+    }
+
     // Mark that we entered this section
     Platform::InterlockedIncrement(thisCounter);