From 559fa50f547cd2b712097a8aebbc10c990cf537d Mon Sep 17 00:00:00 2001
From: Philip Rebohle <philip.rebohle@tu-dortmund.de>
Date: Wed, 24 Aug 2022 12:27:02 +0200
Subject: [PATCH] [d3d11] Introduce d3d11.enableContextLock option

---
 dxvk.conf                       |  8 ++++++++
 src/d3d10/d3d10_multithread.cpp | 17 +++++++++++++----
 src/d3d10/d3d10_multithread.h   |  5 ++++-
 src/d3d11/d3d11_context_imm.cpp |  2 +-
 src/d3d11/d3d11_options.cpp     |  1 +
 src/d3d11/d3d11_options.h       |  5 +++++
 6 files changed, 32 insertions(+), 6 deletions(-)

diff --git a/dxvk.conf b/dxvk.conf
index 6d0aba1e8..d029dce2a 100644
--- a/dxvk.conf
+++ b/dxvk.conf
@@ -236,6 +236,14 @@
 # d3d11.cachedDynamicResources = ""
 
 
+# Force-enables the D3D11 context lock via the ID3D10Multithread
+# interface. This may be useful to debug race conditions.
+#
+# Supported values: True, False
+
+# d3d11.enableContextLock = False
+
+
 # Sets number of pipeline compiler threads.
 # 
 # If the graphics pipeline library feature is enabled, the given
diff --git a/src/d3d10/d3d10_multithread.cpp b/src/d3d10/d3d10_multithread.cpp
index 65932b53d..20a97eef0 100644
--- a/src/d3d10/d3d10_multithread.cpp
+++ b/src/d3d10/d3d10_multithread.cpp
@@ -6,9 +6,12 @@ namespace dxvk {
 
   D3D10Multithread::D3D10Multithread(
           IUnknown*             pParent,
-          BOOL                  Protected)
+          BOOL                  Protected,
+          BOOL                  Force)
   : m_parent    (pParent),
-    m_protected (Protected) {
+    m_protected (Protected || Force),
+    m_enabled   (Protected),
+    m_forced    (Force) {
     
   }
 
@@ -49,12 +52,18 @@ namespace dxvk {
 
   BOOL STDMETHODCALLTYPE D3D10Multithread::SetMultithreadProtected(
           BOOL                  bMTProtect) {
-    return std::exchange(m_protected, bMTProtect);
+    BOOL result = m_enabled;
+    m_enabled = bMTProtect;
+
+    if (!m_forced)
+      m_protected = m_enabled;
+
+    return result;
   }
 
 
   BOOL STDMETHODCALLTYPE D3D10Multithread::GetMultithreadProtected() {
-    return m_protected;
+    return m_enabled;
   }
 
 }
diff --git a/src/d3d10/d3d10_multithread.h b/src/d3d10/d3d10_multithread.h
index 39a736cc0..75d4060f2 100644
--- a/src/d3d10/d3d10_multithread.h
+++ b/src/d3d10/d3d10_multithread.h
@@ -64,7 +64,8 @@ namespace dxvk {
 
     D3D10Multithread(
             IUnknown*             pParent,
-            BOOL                  Protected);
+            BOOL                  Protected,
+            BOOL                  Force);
     
     ~D3D10Multithread();
 
@@ -95,6 +96,8 @@ namespace dxvk {
 
     IUnknown* m_parent;
     BOOL      m_protected;
+    BOOL      m_enabled;
+    BOOL      m_forced;
 
     sync::RecursiveSpinlock m_mutex;
 
diff --git a/src/d3d11/d3d11_context_imm.cpp b/src/d3d11/d3d11_context_imm.cpp
index e754ca608..3aa4d3613 100644
--- a/src/d3d11/d3d11_context_imm.cpp
+++ b/src/d3d11/d3d11_context_imm.cpp
@@ -18,7 +18,7 @@ namespace dxvk {
   : D3D11CommonContext<D3D11ImmediateContext>(pParent, Device, 0, DxvkCsChunkFlag::SingleUse),
     m_csThread(Device, Device->createContext(DxvkContextType::Primary)),
     m_maxImplicitDiscardSize(pParent->GetOptions()->maxImplicitDiscardSize),
-    m_multithread(this, false),
+    m_multithread(this, false, pParent->GetOptions()->enableContextLock),
     m_videoContext(this, Device) {
     EmitCs([
       cDevice                 = m_device,
diff --git a/src/d3d11/d3d11_options.cpp b/src/d3d11/d3d11_options.cpp
index 4874e114e..83c321de0 100644
--- a/src/d3d11/d3d11_options.cpp
+++ b/src/d3d11/d3d11_options.cpp
@@ -25,6 +25,7 @@ namespace dxvk {
     this->invariantPosition     = config.getOption<bool>("d3d11.invariantPosition", true);
     this->floatControls         = config.getOption<bool>("d3d11.floatControls", true);
     this->disableMsaa           = config.getOption<bool>("d3d11.disableMsaa", false);
+    this->enableContextLock     = config.getOption<bool>("d3d11.enableContextLock", false);
     this->deferSurfaceCreation  = config.getOption<bool>("dxgi.deferSurfaceCreation", false);
     this->numBackBuffers        = config.getOption<int32_t>("dxgi.numBackBuffers", 0);
     this->maxFrameLatency       = config.getOption<int32_t>("dxgi.maxFrameLatency", 0);
diff --git a/src/d3d11/d3d11_options.h b/src/d3d11/d3d11_options.h
index dcbef7c3c..67bceaa54 100644
--- a/src/d3d11/d3d11_options.h
+++ b/src/d3d11/d3d11_options.h
@@ -111,6 +111,11 @@ namespace dxvk {
     /// in cached system memory. Enabled automatically when recording
     /// an api trace.
     uint32_t cachedDynamicResources;
+
+    /// Always lock immediate context on every API call. May be
+    /// useful for debugging purposes or when applications have
+    /// race conditions.
+    bool enableContextLock;
   };
   
 }
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