Re: [PATCH] media: vb2: always set buffer cache sync hints

From: Sergey Senozhatsky
Date: Sat Nov 28 2020 - 00:13:02 EST


On (20/11/28 01:50), Tomasz Figa wrote:
> On Sat, Nov 28, 2020 at 1:35 AM Sergey Senozhatsky
> <sergey.senozhatsky@xxxxxxxxx> wrote:
> >
> > On (20/11/27 15:56), Hans Verkuil wrote:
> > > Yes.
> > >
> > > BTW, wouldn't it be sufficient to change this code to:
> > >
> > > if (!q->allow_cache_hints && q->memory != VB2_MEMORY_DMABUF) {
> > > vb->need_cache_sync_on_prepare = 1;
> > > vb->need_cache_sync_on_finish = 1;
> > > }
> >
> > I think it would be sufficient.
>
> Does it matter at this point if allow_cache_hints is set or not?

That's a good question. I'd say that it'll probably make sense to set
need_cache_sync for as many buffers as possible, regardless the queue
configuration (except for ->memory type), just to stay on the safe side.
I can spin another patch version.

-ss