On Fri, Jul 06, 2018 at 09:27:47PM +0100, Chris Wilson wrote: > Quoting Rodrigo Vivi (2018-07-06 21:23:00) > > On Fri, Jul 06, 2018 at 06:49:26PM +0100, Chris Wilson wrote: > > > clflush is an unserialised instruction and the IA manual strongly advises > > > you to serialise it with a mb. To be cautious, apply one before and one > > > after, > > > > my understanding is that we need one before and one after anyways, > > not just a matter of being cautious for being cautious.. > > > > Reviewed-by: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx> > > If you are really careful, you can reduce it to a mb between writes and > the clflush; and vice verse, the mb between clflush and subsequent > reads. It's all about prevent the clflush from overtaking or being > overtaken by the operations it is meant to flush or invalidate > respectively. > > But since we're being paranoid here, do both. hm... makes sense... better to be paranoid... > -Chris > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@xxxxxxxxxxxxxxxxxxxxx > https://lists.freedesktop.org/mailman/listinfo/intel-gfx _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
