<div dir="ltr"><div class="gmail_extra"><div class="gmail_quote">On Thu, Feb 8, 2018 at 4:46 PM, Marek Olšák <<a href="mailto:maraeo@gmail.com" target="_blank">maraeo@gmail.com</a>> wrote: <blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">This is not the correct fix. clear_with_quad calls cso_set_blend. pipe->clear ignores (and should ignore) the blend state. There is no scenario where you would have to call st_update_blend for pipe->clear. I think this is a virgl bug in pipe->clear. </blockquote><div> </div><div><span style="color:rgb(34,34,34);font-family:arial,sans-serif;font-size:small;font-style:normal;font-variant-ligatures:normal;font-variant-caps:normal;font-weight:400;letter-spacing:normal;text-align:start;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px;background-color:rgb(255,255,255);text-decoration-style:initial;text-decoration-color:initial;float:none;display:inline">clear_with_quad is only called if a color mask exists (see is_color_masked). When the state transitions from color-mask exists --> completely unmasked (the clear_buffers case), how is the driver supposed to be notified? </div><div> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"> Marek <div><div class="gmail-h5"> On Fri, Feb 9, 2018 at 1:28 AM, <a href="mailto:gurchetansingh@chromium.org">gurchetansingh@chromium.org</a> <<a href="mailto:gurchetansingh@chromium.org">gurchetansingh@chromium.org</a>> wrote: > From: Gurchetan Singh <<a href="mailto:gurchetansingh@chromium.org">gurchetansingh@chromium.org</a>> > > Consider this series of events: > > glColorMask(GL_FALSE, GL_TRUE, GL_TRUE, GL_TRUE); > glClearColor(0.125f, 0.25f, 0.5f, 1.0f); > glClear(GL_COLOR_BUFFER_BIT); > glColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE); > glClearColor(0.1f, 0.1f, 0.1f, 1.0f); > glClear(GL_COLOR_BUFFER_BIT); > > With virgl, this may render an incorrect result. This is because > there our two paths for clears in Gallium -- one for full clears > (st->pipe->clear) and another for color-masked/scissored clears > (clear_with_quad). We only encode the color mask in the > virgl_encode_blend_state in the clear_with_quad case. > > We should set the colormask the case of full clears as well, since > we need to update the GL state on the host driver. > > With this patch, the number of dEQP GLES2 failures on Virgl with a > nvidia host drivers goes from 260 to 136 with no regressions. > Two representative test cases are: > > dEQP-GLES2.functional.color_clear.masked_scissored_rgb > dEQP-GLES2.functional.color_clear.masked_scissored_rgba > > Note: I tried a virgl specific solution (<a href="http://crrev.com/c/909961" rel="noreferrer" target="_blank">crrev.com/c/909961</a>), however > that caused a regression in dEQP-GLES2.functional.depth_stencil_clear.depth > since the cso_cache was not updated. > --- > src/mesa/state_tracker/st_cb_clear.c | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/src/mesa/state_tracker/st_cb_clear.c b/src/mesa/state_tracker/st_cb_clear.c > index 68677182ab..d8ad2b3b4a 100644 > --- a/src/mesa/state_tracker/st_cb_clear.c > +++ b/src/mesa/state_tracker/st_cb_clear.c > @@ -444,6 +444,13 @@ st_Clear(struct gl_context *ctx, GLbitfield mask) > clear_with_quad(ctx, quad_buffers); > } > if (clear_buffers) { > + /* The colormask may go from a masked value to being completely unmasked. > + * In that case, we should notify the driver via st_update_blend. The cso > + * cache should take care of not emitting old states. > + */ > + if (clear_buffers & PIPE_CLEAR_COLOR) > + st_update_blend(st); > + > /* We can't translate the clear color to the colorbuffer format, > * because different colorbuffers may have different formats. > */ > -- > 2.13.5 > </div></div>> _______________________________________________ > mesa-dev mailing list > <a href="mailto:mesa-dev@lists.freedesktop.org">mesa-dev@lists.freedesktop.org</a> > <a href="https://lists.freedesktop.org/mailman/listinfo/mesa-dev" rel="noreferrer" target="_blank">https://lists.freedesktop.org/mailman/listinfo/mesa-dev</a> </blockquote></div> </div></div>