buffer_cache: Fix race condition

src/video_core/amdgpu/liverpool.cpp

@@ -17,6 +17,8 @@
 #include "video_core/renderer_vulkan/vk_rasterizer.h"
 #include "video_core/renderer_vulkan/vk_scheduler.h"
 
+std::thread::id gpu_id;
+
 namespace AmdGpu {
 
 static const char* dcb_task_name{"DCB_TASK"};
@@ -89,7 +91,7 @@ void Liverpool::ProcessCommands() {
 
 void Liverpool::Process(std::stop_token stoken) {
     Common::SetCurrentThreadName("shadPS4:GpuCommandProcessor");
-
+    gpu_id = std::this_thread::get_id();
     while (!stoken.stop_requested()) {
         {
             std::unique_lock lk{submit_mutex};

src/video_core/buffer_cache/buffer_cache.cpp

@@ -288,13 +288,13 @@ bool BufferCache::CommitPendingDownloads(bool wait_done) {
             }
         }
     };
+    const u64 wait_tick = scheduler.CurrentTick();
+    scheduler.Flush();
     {
         std::scoped_lock lk{queue_mutex};
-        async_downloads.emplace(std::move(writeback_host), scheduler.CurrentTick(),
-                                current_download_tick);
+        async_downloads.emplace(std::move(writeback_host), wait_tick, current_download_tick);
     }
     queue_cv.notify_one();
-    scheduler.Flush();
     if (wait_done) {
         WaitForTargetTick(current_download_tick);
     }

src/video_core/renderer_vulkan/vk_rasterizer.cpp

@@ -62,9 +62,6 @@ void Rasterizer::CpSync() {
 }
 
 bool Rasterizer::CommitPendingDownloads(bool wait_done) {
-    SCOPE_EXIT {
-        scheduler.PopPendingOperations();
-    };
     return buffer_cache.CommitPendingDownloads(wait_done);
 }
 

src/video_core/renderer_vulkan/vk_scheduler.cpp

@@ -8,6 +8,8 @@
 #include "video_core/renderer_vulkan/vk_instance.h"
 #include "video_core/renderer_vulkan/vk_scheduler.h"
 
+extern std::thread::id gpu_id;
+
 namespace Vulkan {
 
 std::mutex Scheduler::submit_mutex;
@@ -68,6 +70,7 @@ void Scheduler::EndRendering() {
 void Scheduler::PopPendingOperations() {
     master_semaphore.Refresh();
     while (!pending_ops.empty() && master_semaphore.IsFree(pending_ops.front().gpu_tick)) {
+        ASSERT(gpu_id == std::this_thread::get_id());
         ASSERT(op_scope == 0);
         ++op_scope;
         pending_ops.front().callback();