On 06/09/16 12:08 PM, Jason Ekstrand wrote: > On Mon, Sep 5, 2016 at 7:39 PM, Michel Dänzer <mic...@daenzer.net > <mailto:mic...@daenzer.net>> wrote: > > From: Michel Dänzer <michel.daen...@amd.com > <mailto:michel.daen...@amd.com>> > > This can make a significant difference for performance with some extreme > test cases such as vblank_mode=0 glxgears. > > Fixes: 1e3218bc5ba2 ("loader/dri3: Overhaul dri3_update_num_back") > Cc: "12.0 11.2" <mesa-sta...@lists.freedesktop.org > <mailto:mesa-sta...@lists.freedesktop.org>> > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=97549 > <https://bugs.freedesktop.org/show_bug.cgi?id=97549> > Signed-off-by: Michel Dänzer <michel.daen...@amd.com > <mailto:michel.daen...@amd.com>> > --- > > I could swear I tested vblank_mode=0 glxgears with my previous change > and couldn't measure any difference, but I can now, so I must have > messed up my previous testing somehow... Apologies for any inconvenience > this caused. > > src/loader/loader_dri3_helper.c | 4 +--- > 1 file changed, 1 insertion(+), 3 deletions(-) > > diff --git a/src/loader/loader_dri3_helper.c > b/src/loader/loader_dri3_helper.c > index 86ae5ae..3ce0352 100644 > --- a/src/loader/loader_dri3_helper.c > +++ b/src/loader/loader_dri3_helper.c > @@ -70,10 +70,8 @@ dri3_update_num_back(struct loader_dri3_drawable > *draw) > { > if (draw->flipping) > draw->num_back = 3; > - else if (draw->vtable->get_swap_interval(draw) != 0) > - draw->num_back = 2; > else > - draw->num_back = 1; > + draw->num_back = 2; > > > With this change, the function is logically identical to the old > function with the async flipping case removed.
Not sure what you mean exactly, but I hope we can agree that the code is easier to understand and reason about now. :) > I'm still not sure why we aren't getting a stall with 3 butters in the > swapinterval=0 flipping case, but if it doesn't have a perf impact, it must > not be a problem. Right, there is a stall, but it doesn't seem significant, at least on my setup. > Reviewed-by: Jason Ekstrand <ja...@jlekstrand.net > <mailto:ja...@jlekstrand.net>> Thanks! -- Earthling Michel Dänzer | http://www.amd.com Libre software enthusiast | Mesa and X developer _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/mesa-dev
