From eceb6710024716433069d705fbd873d6d136c2cc Mon Sep 17 00:00:00 2001 From: Thomas Hellstrom Date: Tue, 20 Jun 2017 21:12:50 +0200 Subject: [PATCH] mesa/st: Reduce the number of frontbuffer flush calls MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit The mesa state tracker was needlessly flushing the front buffer even if it hadn't been drawn to since the last flush. This was happening during glXSwapBuffers if we at some point previously had set that frontbuffer as a read- or draw renderbuffer, or at glFlush() or glFinish() if we at some point previously had rendered to the front buffer. Since the frontbuffer flush typically means a full drawable copy, it's a pretty big waste. Signed-off-by: Thomas Hellstrom Reviewed-by: Marek Olšák Reviewed-by: Sinclair Yeh --- src/mesa/state_tracker/st_cb_flush.c | 37 ++-------------------------- src/mesa/state_tracker/st_manager.c | 12 ++++++--- 2 files changed, 10 insertions(+), 39 deletions(-) diff --git a/src/mesa/state_tracker/st_cb_flush.c b/src/mesa/state_tracker/st_cb_flush.c index 6442fc92253..8375308c3e2 100644 --- a/src/mesa/state_tracker/st_cb_flush.c +++ b/src/mesa/state_tracker/st_cb_flush.c @@ -46,35 +46,6 @@ #include "util/u_gen_mipmap.h" -/** Check if we have a front color buffer and if it's been drawn to. */ -static inline GLboolean -is_front_buffer_dirty(struct st_context *st) -{ - struct gl_framebuffer *fb = st->ctx->DrawBuffer; - struct st_renderbuffer *strb - = st_renderbuffer(fb->Attachment[BUFFER_FRONT_LEFT].Renderbuffer); - return strb && strb->defined; -} - - -/** - * Tell the screen to display the front color buffer on-screen. - */ -static void -display_front_buffer(struct st_context *st) -{ - struct gl_framebuffer *fb = st->ctx->DrawBuffer; - struct st_renderbuffer *strb - = st_renderbuffer(fb->Attachment[BUFFER_FRONT_LEFT].Renderbuffer); - - if (strb) { - /* Hook for copying "fake" frontbuffer if necessary: - */ - st_manager_flush_frontbuffer(st); - } -} - - void st_flush(struct st_context *st, struct pipe_fence_handle **fence, unsigned flags) @@ -120,9 +91,7 @@ static void st_glFlush(struct gl_context *ctx) */ st_flush(st, NULL, 0); - if (is_front_buffer_dirty(st)) { - display_front_buffer(st); - } + st_manager_flush_frontbuffer(st); } @@ -135,9 +104,7 @@ static void st_glFinish(struct gl_context *ctx) st_finish(st); - if (is_front_buffer_dirty(st)) { - display_front_buffer(st); - } + st_manager_flush_frontbuffer(st); } diff --git a/src/mesa/state_tracker/st_manager.c b/src/mesa/state_tracker/st_manager.c index 62924b099e9..28cf0234cd6 100644 --- a/src/mesa/state_tracker/st_manager.c +++ b/src/mesa/state_tracker/st_manager.c @@ -1036,11 +1036,15 @@ st_manager_flush_frontbuffer(struct st_context *st) if (stfb) strb = st_renderbuffer(stfb->Base.Attachment[BUFFER_FRONT_LEFT].Renderbuffer); - if (!strb) - return; - /* never a dummy fb */ - stfb->iface->flush_front(&st->iface, stfb->iface, ST_ATTACHMENT_FRONT_LEFT); + /* Do we have a front color buffer and has it been drawn to since last + * frontbuffer flush? + */ + if (strb && strb->defined) { + stfb->iface->flush_front(&st->iface, stfb->iface, + ST_ATTACHMENT_FRONT_LEFT); + strb->defined = GL_FALSE; + } } /** -- 2.30.2