From 5ad62e7bfccf6655e1aa355e31d23ab86e163b50 Mon Sep 17 00:00:00 2001 From: ReinUsesLisp Date: Tue, 2 Mar 2021 02:44:19 -0300 Subject: [PATCH] buffer_cache: Heuristically decide to skip cache on uniform buffers MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Some games benefit from skipping caches (Pokémon Sword), and others don't (Animal Crossing: New Horizons). Add an heuristic to decide this at runtime. The cache hit ratio has to be ~98% or better to not skip the cache. There are 16 frames of buffer. --- src/video_core/buffer_cache/buffer_cache.h | 45 ++++++++++++++----- .../renderer_opengl/gl_buffer_cache.cpp | 3 +- 2 files changed, 37 insertions(+), 11 deletions(-) diff --git a/src/video_core/buffer_cache/buffer_cache.h b/src/video_core/buffer_cache/buffer_cache.h index 2a6844ab1..4de1e37e5 100644 --- a/src/video_core/buffer_cache/buffer_cache.h +++ b/src/video_core/buffer_cache/buffer_cache.h @@ -9,6 +9,7 @@ #include #include #include +#include #include #include #include @@ -91,7 +92,7 @@ class BufferCache { }; public: - static constexpr u32 SKIP_CACHE_SIZE = 4096; + static constexpr u32 DEFAULT_SKIP_CACHE_SIZE = 4096; explicit BufferCache(VideoCore::RasterizerInterface& rasterizer_, Tegra::Engines::Maxwell3D& maxwell3d_, @@ -240,9 +241,9 @@ private: template void ChangeRegister(BufferId buffer_id); - void SynchronizeBuffer(Buffer& buffer, VAddr cpu_addr, u32 size); + bool SynchronizeBuffer(Buffer& buffer, VAddr cpu_addr, u32 size); - void SynchronizeBufferImpl(Buffer& buffer, VAddr cpu_addr, u32 size); + bool SynchronizeBufferImpl(Buffer& buffer, VAddr cpu_addr, u32 size); void UploadMemory(Buffer& buffer, u64 total_size_bytes, u64 largest_copy, std::span copies); @@ -297,6 +298,11 @@ private: std::array fast_bound_uniform_buffers{}; + std::array uniform_cache_hits{}; + std::array uniform_cache_shots{}; + + u32 uniform_buffer_skip_cache_size = DEFAULT_SKIP_CACHE_SIZE; + bool has_deleted_buffers = false; std::conditional_t, Empty> @@ -328,6 +334,19 @@ BufferCache

::BufferCache(VideoCore::RasterizerInterface& rasterizer_, template void BufferCache

::TickFrame() { + // Calculate hits and shots and move hit bits to the right + const u32 hits = std::reduce(uniform_cache_hits.begin(), uniform_cache_hits.end()); + const u32 shots = std::reduce(uniform_cache_shots.begin(), uniform_cache_shots.end()); + std::copy_n(uniform_cache_hits.begin(), uniform_cache_hits.size() - 1, + uniform_cache_hits.begin() + 1); + std::copy_n(uniform_cache_shots.begin(), uniform_cache_shots.size() - 1, + uniform_cache_shots.begin() + 1); + uniform_cache_hits[0] = 0; + uniform_cache_shots[0] = 0; + + const bool skip_preferred = hits * 256 < shots * 251; + uniform_buffer_skip_cache_size = skip_preferred ? DEFAULT_SKIP_CACHE_SIZE : 0; + delayed_destruction_ring.Tick(); } @@ -671,7 +690,7 @@ void BufferCache

::BindHostGraphicsUniformBuffer(size_t stage, u32 index, u32 const VAddr cpu_addr = binding.cpu_addr; const u32 size = binding.size; Buffer& buffer = slot_buffers[binding.buffer_id]; - if (size <= SKIP_CACHE_SIZE && !buffer.IsRegionGpuModified(cpu_addr, size)) { + if (size <= uniform_buffer_skip_cache_size && !buffer.IsRegionGpuModified(cpu_addr, size)) { if constexpr (IS_OPENGL) { if (runtime.HasFastBufferSubData()) { // Fast path for Nvidia @@ -692,7 +711,12 @@ void BufferCache

::BindHostGraphicsUniformBuffer(size_t stage, u32 index, u32 return; } // Classic cached path - SynchronizeBuffer(buffer, cpu_addr, size); + const bool sync_cached = SynchronizeBuffer(buffer, cpu_addr, size); + if (sync_cached) { + ++uniform_cache_hits[0]; + } + ++uniform_cache_shots[0]; + if (!needs_bind && !HasFastUniformBufferBound(stage, binding_index)) { // Skip binding if it's not needed and if the bound buffer is not the fast version // This exists to avoid instances where the fast buffer is bound and a GPU write happens @@ -1106,15 +1130,15 @@ void BufferCache

::ChangeRegister(BufferId buffer_id) { } template -void BufferCache

::SynchronizeBuffer(Buffer& buffer, VAddr cpu_addr, u32 size) { +bool BufferCache

::SynchronizeBuffer(Buffer& buffer, VAddr cpu_addr, u32 size) { if (buffer.CpuAddr() == 0) { - return; + return true; } - SynchronizeBufferImpl(buffer, cpu_addr, size); + return SynchronizeBufferImpl(buffer, cpu_addr, size); } template -void BufferCache

::SynchronizeBufferImpl(Buffer& buffer, VAddr cpu_addr, u32 size) { +bool BufferCache

::SynchronizeBufferImpl(Buffer& buffer, VAddr cpu_addr, u32 size) { boost::container::small_vector copies; u64 total_size_bytes = 0; u64 largest_copy = 0; @@ -1128,10 +1152,11 @@ void BufferCache

::SynchronizeBufferImpl(Buffer& buffer, VAddr cpu_addr, u32 s largest_copy = std::max(largest_copy, range_size); }); if (total_size_bytes == 0) { - return; + return true; } const std::span copies_span(copies.data(), copies.size()); UploadMemory(buffer, total_size_bytes, largest_copy, copies_span); + return false; } template diff --git a/src/video_core/renderer_opengl/gl_buffer_cache.cpp b/src/video_core/renderer_opengl/gl_buffer_cache.cpp index 6da3906a4..c225d1fc9 100644 --- a/src/video_core/renderer_opengl/gl_buffer_cache.cpp +++ b/src/video_core/renderer_opengl/gl_buffer_cache.cpp @@ -73,7 +73,8 @@ BufferCacheRuntime::BufferCacheRuntime(const Device& device_) for (auto& stage_uniforms : fast_uniforms) { for (OGLBuffer& buffer : stage_uniforms) { buffer.Create(); - glNamedBufferData(buffer.handle, BufferCache::SKIP_CACHE_SIZE, nullptr, GL_STREAM_DRAW); + glNamedBufferData(buffer.handle, BufferCache::DEFAULT_SKIP_CACHE_SIZE, nullptr, + GL_STREAM_DRAW); } } for (auto& stage_uniforms : copy_uniforms) {