config: Add readbacks config option

src/common/config.cpp

@@ -51,6 +51,7 @@ static bool isShowSplash = false;
 static std::string isSideTrophy = "right";
 static bool isNullGpu = false;
 static bool shouldCopyGPUBuffers = false;
+static bool readbacksEnabled = false;
 static bool shouldDumpShaders = false;
 static bool shouldPatchShaders = true;
 static u32 vblankDivider = 1;
@@ -240,6 +241,10 @@ bool copyGPUCmdBuffers() {
     return shouldCopyGPUBuffers;
 }
 
+bool readbacks() {
+    return readbacksEnabled;
+}
+
 bool dumpShaders() {
     return shouldDumpShaders;
 }
@@ -344,6 +349,10 @@ void setCopyGPUCmdBuffers(bool enable) {
     shouldCopyGPUBuffers = enable;
 }
 
+void setReadbacks(bool enable) {
+    readbacksEnabled = enable;
+}
+
 void setDumpShaders(bool enable) {
     shouldDumpShaders = enable;
 }
@@ -586,6 +595,7 @@ void load(const std::filesystem::path& path) {
         screenHeight = toml::find_or<int>(gpu, "screenHeight", screenHeight);
         isNullGpu = toml::find_or<bool>(gpu, "nullGpu", false);
         shouldCopyGPUBuffers = toml::find_or<bool>(gpu, "copyGPUBuffers", false);
+        readbacksEnabled = toml::find_or<bool>(gpu, "readbacks", false);
         shouldDumpShaders = toml::find_or<bool>(gpu, "dumpShaders", false);
         shouldPatchShaders = toml::find_or<bool>(gpu, "patchShaders", true);
         vblankDivider = toml::find_or<int>(gpu, "vblankDivider", 1);
@@ -735,6 +745,7 @@ void save(const std::filesystem::path& path) {
     data["GPU"]["screenHeight"] = screenHeight;
     data["GPU"]["nullGpu"] = isNullGpu;
     data["GPU"]["copyGPUBuffers"] = shouldCopyGPUBuffers;
+    data["GPU"]["readbacks"] = readbacksEnabled;
     data["GPU"]["dumpShaders"] = shouldDumpShaders;
     data["GPU"]["patchShaders"] = shouldPatchShaders;
     data["GPU"]["vblankDivider"] = vblankDivider;

src/common/config.h

@@ -45,6 +45,8 @@ bool nullGpu();
 void setNullGpu(bool enable);
 bool copyGPUCmdBuffers();
 void setCopyGPUCmdBuffers(bool enable);
+bool readbacks();
+void setReadbacks(bool enable);
 bool dumpShaders();
 void setDumpShaders(bool enable);
 u32 vblankDiv();

src/video_core/amdgpu/liverpool.cpp

@@ -77,7 +77,7 @@ void Liverpool::ProcessCommands() {
     while (num_commands) {
         Common::UniqueFunction<void> callback{};
         {
-            std::unique_lock lk{submit_mutex};
+            std::scoped_lock lk{submit_mutex};
             callback = std::move(command_queue.front());
             command_queue.pop();
             --num_commands;

src/video_core/amdgpu/liverpool.h

@@ -8,6 +8,7 @@
 #include <coroutine>
 #include <exception>
 #include <mutex>
+#include <semaphore>
 #include <span>
 #include <thread>
 #include <vector>
@@ -1512,11 +1513,29 @@ public:
         rasterizer = rasterizer_;
     }
 
-    void SendCommand(Common::UniqueFunction<void>&& func) {
-        std::scoped_lock lk{submit_mutex};
-        command_queue.emplace(std::move(func));
-        ++num_commands;
-        submit_cv.notify_one();
+    template <bool wait_done = false>
+    void SendCommand(auto&& func) {
+        if (std::this_thread::get_id() == gpu_id) {
+            return func();
+        }
+        if constexpr (wait_done) {
+            std::binary_semaphore sem{0};
+            {
+                std::scoped_lock lk{submit_mutex};
+                command_queue.emplace([&sem, &func] {
+                    func();
+                    sem.release();
+                });
+                ++num_commands;
+                submit_cv.notify_one();
+            }
+            sem.acquire();
+        } else {
+            std::scoped_lock lk{submit_mutex};
+            command_queue.emplace(std::move(func));
+            ++num_commands;
+            submit_cv.notify_one();
+        }
     }
 
     void ReserveCopyBufferSpace() {
@@ -1542,7 +1561,6 @@ public:
         u32 tmp_dwords;
     };
     Common::SlotVector<AscQueueInfo> asc_queues{};
-    std::thread::id gpu_id;
 
 private:
     struct Task {
@@ -1628,6 +1646,7 @@ private:
     std::mutex submit_mutex;
     std::condition_variable_any submit_cv;
     std::queue<Common::UniqueFunction<void>> command_queue{};
+    std::thread::id gpu_id;
     int curr_qid{-1};
 };
 

src/video_core/buffer_cache/buffer_cache.cpp

@@ -2,8 +2,8 @@
 // SPDX-License-Identifier: GPL-2.0-or-later
 
 #include <algorithm>
-#include <semaphore>
 #include "common/alignment.h"
+#include "common/config.h"
 #include "common/debug.h"
 #include "common/scope_exit.h"
 #include "common/types.h"
@@ -136,25 +136,17 @@ void BufferCache::InvalidateMemory(VAddr device_addr, u64 size) {
     if (!IsRegionRegistered(device_addr, size)) {
         return;
     }
-    if (memory_tracker->IsRegionGpuModified(device_addr, size)) {
+    if (Config::readbacks() && memory_tracker->IsRegionGpuModified(device_addr, size)) {
         ReadMemory(device_addr, size);
     }
     memory_tracker->MarkRegionAsCpuModified(device_addr, size);
 }
 
 void BufferCache::ReadMemory(VAddr device_addr, u64 size) {
-    if (std::this_thread::get_id() != liverpool->gpu_id) {
-        std::binary_semaphore command_wait{0};
-        liverpool->SendCommand([this, &command_wait, device_addr, size] {
-            Buffer& buffer = slot_buffers[FindBuffer(device_addr, size)];
-            DownloadBufferMemory(buffer, device_addr, size);
-            command_wait.release();
-        });
-        command_wait.acquire();
-    } else {
+    liverpool->SendCommand<true>([this, device_addr, size] {
         Buffer& buffer = slot_buffers[FindBuffer(device_addr, size)];
         DownloadBufferMemory(buffer, device_addr, size);
-    }
+    });
 }
 
 void BufferCache::DownloadBufferMemory(Buffer& buffer, VAddr device_addr, u64 size) {

src/video_core/buffer_cache/region_definitions.h

@@ -3,7 +3,6 @@
 
 #pragma once
 
-#include <array>
 #include "common/bit_array.h"
 #include "common/types.h"
 
@@ -20,9 +19,8 @@ constexpr u64 NUM_PAGES_PER_REGION = TRACKER_HIGHER_PAGE_SIZE / TRACKER_BYTES_PE
 enum class Type {
     CPU,
     GPU,
-    Writeable,
 };
 
 using RegionBits = Common::BitArray<NUM_PAGES_PER_REGION>;
 
-} // namespace VideoCore
+} // namespace VideoCore

src/video_core/buffer_cache/region_manager.h

@@ -4,6 +4,7 @@
 #pragma once
 
 #include <mutex>
+#include "common/config.h"
 #include "common/div_ceil.h"
 
 #ifdef __linux__
@@ -47,29 +48,19 @@ public:
 
     template <Type type>
     RegionBits& GetRegionBits() noexcept {
-        static_assert(type != Type::Writeable);
         if constexpr (type == Type::CPU) {
             return cpu;
         } else if constexpr (type == Type::GPU) {
             return gpu;
-        } else if constexpr (type == Type::Writeable) {
-            return writeable;
-        } else {
-            static_assert(false, "Invalid type");
         }
     }
 
     template <Type type>
     const RegionBits& GetRegionBits() const noexcept {
-        static_assert(type != Type::Writeable);
         if constexpr (type == Type::CPU) {
             return cpu;
         } else if constexpr (type == Type::GPU) {
             return gpu;
-        } else if constexpr (type == Type::Writeable) {
-            return writeable;
-        } else {
-            static_assert(false, "Invalid type");
         }
     }
 
@@ -90,7 +81,6 @@ public:
             return;
         }
         std::scoped_lock lk{lock};
-        static_assert(type != Type::Writeable);
 
         RegionBits& bits = GetRegionBits<type>();
         if constexpr (enable) {
@@ -100,7 +90,7 @@ public:
         }
         if constexpr (type == Type::CPU) {
             UpdateProtection<!enable, false>();
-        } else {
+        } else if (Config::readbacks()) {
             UpdateProtection<enable, true>();
         }
     }
@@ -124,7 +114,6 @@ public:
             return;
         }
         std::scoped_lock lk{lock};
-        static_assert(type != Type::Writeable);
 
         RegionBits& bits = GetRegionBits<type>();
         RegionBits mask(bits, start_page, end_page);
@@ -137,7 +126,7 @@ public:
             bits.UnsetRange(start_page, end_page);
             if constexpr (type == Type::CPU) {
                 UpdateProtection<true, false>();
-            } else {
+            } else if (Config::readbacks()) {
                 UpdateProtection<false, true>();
             }
         }
@@ -159,7 +148,6 @@ public:
             return false;
         }
         std::scoped_lock lk{lock};
-        static_assert(type != Type::Writeable);
 
         const RegionBits& bits = GetRegionBits<type>();
         RegionBits test(bits, start_page, end_page);