Clarify StepBarrier

src/Ryujinx.Cpu/AppleHv/HvExecutionContext.cs

@@ -167,7 +167,7 @@ namespace Ryujinx.Cpu.AppleHv
             }
         }
 
-        public Barrier StepBarrier { get; private set; }
+        public Barrier StepBarrier { get; }
 
         /// <inheritdoc/>
         public void StopRunning()

src/Ryujinx.Cpu/IExecutionContext.cs

@@ -130,6 +130,7 @@ namespace Ryujinx.Cpu
         /// Step barrier
         /// </summary>
         /// <remarks>
+        /// The participant count should be 2.
         /// Should be signaled and waited on twice after single-stepping.
         /// </remarks>
         Barrier StepBarrier { get; }