vk_renderpass_cache: Bring back renderpass flushing

src/video_core/renderer_vulkan/vk_renderpass_cache.cpp

@@ -12,6 +12,8 @@
 
 namespace Vulkan {
 
+constexpr u32 MIN_DRAWS_TO_FLUSH = 20;
+
 using VideoCore::PixelFormat;
 using VideoCore::SurfaceType;
 
@@ -46,6 +48,7 @@ void RenderpassCache::BeginRendering(const Framebuffer* framebuffer,
 
 void RenderpassCache::BeginRendering(const RenderPass& new_pass) {
     if (pass == new_pass) [[likely]] {
+        num_draws++;
         return;
     }
 
@@ -111,6 +114,13 @@ void RenderpassCache::EndRendering() {
                                vk::DependencyFlagBits::eByRegion, 0, nullptr, 0, nullptr,
                                num_barriers, barriers.data());
     });
+
+    // The Mali guide recommends flushing at the end of each major renderpass
+    // Testing has shown this has a significant effect on rendering performance
+    if (num_draws > MIN_DRAWS_TO_FLUSH && instance.ShouldFlush()) {
+        scheduler.Flush();
+        num_draws = 0;
+    }
 }
 
 vk::RenderPass RenderpassCache::GetRenderpass(VideoCore::PixelFormat color,

src/video_core/renderer_vulkan/vk_renderpass_cache.h

@@ -68,6 +68,7 @@ private:
     std::array<vk::Image, 2> images;
     std::array<vk::ImageAspectFlags, 2> aspects;
     RenderPass pass{};
+    u32 num_draws{};
 };
 
 } // namespace Vulkan