Re: [PATCH v4 03/14] dma-buf/fence-chain: Add fence deadline support

[Rob Clark]

On Wed, Feb 22, 2023 at 2:27 AM Tvrtko Ursulin
<tvrtko.ursulin@xxxxxxxxxxxxxxx> wrote:
>
>
> On 18/02/2023 21:15, Rob Clark wrote:
> > From: Rob Clark <robdclark@xxxxxxxxxxxx>
> >
> > Propagate the deadline to all the fences in the chain.
> >
> > Signed-off-by: Rob Clark <robdclark@xxxxxxxxxxxx>
> > Reviewed-by: Christian König <christian.koenig@xxxxxxx> for this one.
> > ---
> >   drivers/dma-buf/dma-fence-chain.c | 13 +++++++++++++
> >   1 file changed, 13 insertions(+)
> >
> > diff --git a/drivers/dma-buf/dma-fence-chain.c b/drivers/dma-buf/dma-fence-chain.c
> > index a0d920576ba6..4684874af612 100644
> > --- a/drivers/dma-buf/dma-fence-chain.c
> > +++ b/drivers/dma-buf/dma-fence-chain.c
> > @@ -206,6 +206,18 @@ static void dma_fence_chain_release(struct dma_fence *fence)
> >       dma_fence_free(fence);
> >   }
> >
> > +
> > +static void dma_fence_chain_set_deadline(struct dma_fence *fence,
> > +                                      ktime_t deadline)
> > +{
> > +     dma_fence_chain_for_each(fence, fence) {
> > +             struct dma_fence_chain *chain = to_dma_fence_chain(fence);
> > +             struct dma_fence *f = chain ? chain->fence : fence;
>
> Low level comment - above two lines could be replaced with:
>
>         struct dma_fence *f = dma_fence_chain_contained(fence);
>
> Although to be fair I am not sure that wouldn't be making it less
> readable. From the point of view that fence might not be a chain, so
> dma_fence_chain_contained() reads a bit dodgy as an API.

It does seem to be the canonical way to do it since 18f5fad275ef
("dma-buf: add dma_fence_chain_contained helper").. looks like I
missed that when I rebased.  I guess for consistency it's best that I
use the helper.

BR,
-R

> Regards,
>
> Tvrtko
>
> > +
> > +             dma_fence_set_deadline(f, deadline);
> > +     }
> > +}
> > +
> >   const struct dma_fence_ops dma_fence_chain_ops = {
> >       .use_64bit_seqno = true,
> >       .get_driver_name = dma_fence_chain_get_driver_name,
> > @@ -213,6 +225,7 @@ const struct dma_fence_ops dma_fence_chain_ops = {
> >       .enable_signaling = dma_fence_chain_enable_signaling,
> >       .signaled = dma_fence_chain_signaled,
> >       .release = dma_fence_chain_release,
> > +     .set_deadline = dma_fence_chain_set_deadline,
> >   };
> >   EXPORT_SYMBOL(dma_fence_chain_ops);
> >