[Mesa-dev] [PATCH v5] etnaviv: fix resource usage tracking across different pipe_context's

[Christian Gmeiner]

Am Sa., 16. März 2019 um 20:55 Uhr schrieb Marek Vasut <marex at denx.de>:
>
> On 2/22/19 10:30 AM, Boris Brezillon wrote:
> > On Thu, 21 Feb 2019 23:29:53 +0100
> > Boris Brezillon <boris.brezillon at collabora.com> wrote:
> >
> >> Christian, Marek,
> >>
> >> On Wed, 30 Jan 2019 05:28:14 +0100
> >> Marek Vasut <marex at denx.de> wrote:
> >>
> >>> From: Christian Gmeiner <christian.gmeiner at gmail.com>
> >>>
> >>> A pipe_resource can be shared by all the pipe_context's hanging off the
> >>> same pipe_screen.
> >>
> >> We seem to be impacted by the problem you're fixing here, but, while
> >> this patch definitely make things much better, the problem does not
> >> seem to be entirely fixed (at least in our case).
> >>
> >> A bit more context: we have Qt App using QtWebEngine to render html
> >> content. When we call QtWebEngine::initialize(), which as for effect
> >> to allow shared GL contexts, we sometimes notice that part of the web
> >> page is mis-rendered. That does not happen when we omit the
> >> QtWebEngine::initialize() call.
> >> As said above, this patch make those rendering issues less likely to
> >> happen, but we still have the problem from time to time. So I thought
> >> I'd share my guesses about what could cause these issues before
> >> debugging it further.
> >>
> >> First thing I noticed: I couldn't reproduce the problem with [1]
> >> applied (+ a tiny change forcing CPU-based tiling no matter the size of
> >> the region to tile/untile). So, my guess is that it's related to how we
> >> handle GPU-based tiling/untiling.
> >> Also noticed that we're testing the rsc->status here [2] without the
> >> screen->lock held, and there might be a race with another thread calling
> >> resource_used(). We might also lack a resource_read(ctx, &src->base)
> >> here [3]. But even after fixing those problems, the rendering issues
> >> are not gone.
> >
> > I tested again with the following diff applied on top of your patch, and
> > the remaining rendering issues we had seem to be gone (don't know what I
> > messed up in my previous tests :-/).
> >
> > --->8---
> > diff --git a/src/gallium/drivers/etnaviv/etnaviv_rs.c b/src/gallium/drivers/etnaviv/etnaviv_rs.c
> > index fc4f65dbeee1..b8c8b96a6f72 100644
> > --- a/src/gallium/drivers/etnaviv/etnaviv_rs.c
> > +++ b/src/gallium/drivers/etnaviv/etnaviv_rs.c
> > @@ -729,6 +729,7 @@ etna_try_rs_blit(struct pipe_context *pctx,
> >
> >     etna_submit_rs_state(ctx, &copy_to_screen);
> >     resource_written(ctx, &dst->base);
> > +   resource_read(ctx, &src->base);
> >     dst->seqno++;
> >     dst->levels[blit_info->dst.level].ts_valid = false;
> >     ctx->dirty |= ETNA_DIRTY_DERIVE_TS;
> While the V6 of this patch [1] is now in mesa upstream, this hunk is
> missing from the V6 . Any special reason for that or is this just an
> omission ?
>

This and an other change was done in separates commits - see:

https://cgit.freedesktop.org/mesa/mesa/commit/?id=7244e768040859126a5b74023f587beaa8bef81c
https://cgit.freedesktop.org/mesa/mesa/commit/?id=c56e73449698c31fe72b99a95b7e4ecdb2985b73

So everything went in.

-- 
greets
--
Christian Gmeiner, MSc

https://christian-gmeiner.info