From 39c97f1b652898dbd0e5e6d028de2ba4b9fa94a0 Mon Sep 17 00:00:00 2001
From: ReinUsesLisp <reinuseslisp@airmail.cc>
Date: Thu, 18 Jun 2020 21:53:47 -0300
Subject: gl_stream_buffer: Use InvalidateBufferData instead unmap and map

Making the stream buffer resident increases GPU usage significantly on
some games. This seems to be addressed invalidating the stream buffer
with InvalidateBufferData instead of using a Unmap + Map (with
invalidation flags).
---
 src/video_core/renderer_opengl/gl_stream_buffer.cpp | 19 +++++--------------
 src/video_core/renderer_opengl/gl_stream_buffer.h   |  1 -
 2 files changed, 5 insertions(+), 15 deletions(-)

diff --git a/src/video_core/renderer_opengl/gl_stream_buffer.cpp b/src/video_core/renderer_opengl/gl_stream_buffer.cpp
index 164df4feb..3655ff629 100644
--- a/src/video_core/renderer_opengl/gl_stream_buffer.cpp
+++ b/src/video_core/renderer_opengl/gl_stream_buffer.cpp
@@ -57,30 +57,21 @@ std::tuple<u8*, GLintptr, bool> OGLStreamBuffer::Map(GLsizeiptr size, GLintptr a
 
     bool invalidate = false;
     if (buffer_pos + size > buffer_size) {
+        MICROPROFILE_SCOPE(OpenGL_StreamBuffer);
+        glInvalidateBufferData(gl_buffer.handle);
+
         buffer_pos = 0;
         invalidate = true;
-
-        glUnmapNamedBuffer(gl_buffer.handle);
-    }
-
-    if (invalidate) {
-        static const GLbitfield flags = GL_MAP_WRITE_BIT | GL_MAP_PERSISTENT_BIT |
-                                        GL_MAP_INVALIDATE_BUFFER_BIT | GL_MAP_FLUSH_EXPLICIT_BIT;
-
-        MICROPROFILE_SCOPE(OpenGL_StreamBuffer);
-        mapped_ptr = static_cast<u8*>(
-            glMapNamedBufferRange(gl_buffer.handle, buffer_pos, buffer_size - buffer_pos, flags));
-        mapped_offset = buffer_pos;
     }
 
-    return std::make_tuple(mapped_ptr + buffer_pos - mapped_offset, buffer_pos, invalidate);
+    return std::make_tuple(mapped_ptr + buffer_pos, buffer_pos, invalidate);
 }
 
 void OGLStreamBuffer::Unmap(GLsizeiptr size) {
     ASSERT(size <= mapped_size);
 
     if (size > 0) {
-        glFlushMappedNamedBufferRange(gl_buffer.handle, buffer_pos - mapped_offset, size);
+        glFlushMappedNamedBufferRange(gl_buffer.handle, buffer_pos, size);
     }
 
     buffer_pos += size;
diff --git a/src/video_core/renderer_opengl/gl_stream_buffer.h b/src/video_core/renderer_opengl/gl_stream_buffer.h
index e67a82980..307a67113 100644
--- a/src/video_core/renderer_opengl/gl_stream_buffer.h
+++ b/src/video_core/renderer_opengl/gl_stream_buffer.h
@@ -48,7 +48,6 @@ private:
     GLuint64EXT gpu_address = 0;
     GLintptr buffer_pos = 0;
     GLsizeiptr buffer_size = 0;
-    GLintptr mapped_offset = 0;
     GLsizeiptr mapped_size = 0;
     u8* mapped_ptr = nullptr;
 };
-- 
cgit v1.2.3