diff mbox series

[v3,7/9] dma-buf/fence-chain: Add fence deadline support

Message ID 20210903184806.1680887-8-robdclark@gmail.com (mailing list archive)
State New, archived
Headers show
Series dma-fence: Deadline awareness | expand

Commit Message

Rob Clark Sept. 3, 2021, 6:47 p.m. UTC 
From: Rob Clark <robdclark@chromium.org>

Signed-off-by: Rob Clark <robdclark@chromium.org>
---
 drivers/dma-buf/dma-fence-chain.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

Comments

Daniel Vetter Sept. 8, 2021, 5:54 p.m. UTC | #1 
On Fri, Sep 03, 2021 at 11:47:58AM -0700, Rob Clark wrote:
> From: Rob Clark <robdclark@chromium.org>
> 
> Signed-off-by: Rob Clark <robdclark@chromium.org>
> ---
>  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 1b4cb3e5cec9..736a9ad3ea6d 100644
> --- a/drivers/dma-buf/dma-fence-chain.c
> +++ b/drivers/dma-buf/dma-fence-chain.c
> @@ -208,6 +208,18 @@ 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;

Doesn't this just end up calling set_deadline on a chain, potenetially
resulting in recursion? Also I don't think this should ever happen, why
did you add that?
-Daniel

> +
> +		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,
> @@ -215,6 +227,7 @@ 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);
>  
> -- 
> 2.31.1
>
Rob Clark Sept. 8, 2021, 6:19 p.m. UTC | #2 
On Wed, Sep 8, 2021 at 10:54 AM Daniel Vetter <daniel@ffwll.ch> wrote:
>
> On Fri, Sep 03, 2021 at 11:47:58AM -0700, Rob Clark wrote:
> > From: Rob Clark <robdclark@chromium.org>
> >
> > Signed-off-by: Rob Clark <robdclark@chromium.org>
> > ---
> >  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 1b4cb3e5cec9..736a9ad3ea6d 100644
> > --- a/drivers/dma-buf/dma-fence-chain.c
> > +++ b/drivers/dma-buf/dma-fence-chain.c
> > @@ -208,6 +208,18 @@ 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;
>
> Doesn't this just end up calling set_deadline on a chain, potenetially
> resulting in recursion? Also I don't think this should ever happen, why
> did you add that?

Tbh the fence-chain was the part I was a bit fuzzy about, and the main
reason I added igt tests.  The iteration is similar to how, for ex,
dma_fence_chain_signaled() work, and according to the igt test it does
what was intended

BR,
-R

> -Daniel
>
> > +
> > +             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,
> > @@ -215,6 +227,7 @@ 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);
> >
> > --
> > 2.31.1
> >
>
> --
> Daniel Vetter
> Software Engineer, Intel Corporation
> http://blog.ffwll.ch
Daniel Vetter Sept. 8, 2021, 6:45 p.m. UTC | #3 
On Wed, Sep 08, 2021 at 11:19:15AM -0700, Rob Clark wrote:
> On Wed, Sep 8, 2021 at 10:54 AM Daniel Vetter <daniel@ffwll.ch> wrote:
> >
> > On Fri, Sep 03, 2021 at 11:47:58AM -0700, Rob Clark wrote:
> > > From: Rob Clark <robdclark@chromium.org>
> > >
> > > Signed-off-by: Rob Clark <robdclark@chromium.org>
> > > ---
> > >  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 1b4cb3e5cec9..736a9ad3ea6d 100644
> > > --- a/drivers/dma-buf/dma-fence-chain.c
> > > +++ b/drivers/dma-buf/dma-fence-chain.c
> > > @@ -208,6 +208,18 @@ 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;
> >
> > Doesn't this just end up calling set_deadline on a chain, potenetially
> > resulting in recursion? Also I don't think this should ever happen, why
> > did you add that?
> 
> Tbh the fence-chain was the part I was a bit fuzzy about, and the main
> reason I added igt tests.  The iteration is similar to how, for ex,
> dma_fence_chain_signaled() work, and according to the igt test it does
> what was intended

Huh indeed. Maybe something we should fix, like why does the
dma_fence_chain_for_each not give you the upcast chain pointer ... I guess
this also needs more Christian and less me.
-Daniel

> 
> BR,
> -R
> 
> > -Daniel
> >
> > > +
> > > +             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,
> > > @@ -215,6 +227,7 @@ 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);
> > >
> > > --
> > > 2.31.1
> > >
> >
> > --
> > Daniel Vetter
> > Software Engineer, Intel Corporation
> > http://blog.ffwll.ch
Christian König Sept. 9, 2021, 6:31 a.m. UTC | #4 
Am 08.09.21 um 20:45 schrieb Daniel Vetter:
> On Wed, Sep 08, 2021 at 11:19:15AM -0700, Rob Clark wrote:
>> On Wed, Sep 8, 2021 at 10:54 AM Daniel Vetter <daniel@ffwll.ch> wrote:
>>> On Fri, Sep 03, 2021 at 11:47:58AM -0700, Rob Clark wrote:
>>>> From: Rob Clark <robdclark@chromium.org>
>>>>
>>>> Signed-off-by: Rob Clark <robdclark@chromium.org>
>>>> ---
>>>>   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 1b4cb3e5cec9..736a9ad3ea6d 100644
>>>> --- a/drivers/dma-buf/dma-fence-chain.c
>>>> +++ b/drivers/dma-buf/dma-fence-chain.c
>>>> @@ -208,6 +208,18 @@ 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;
>>> Doesn't this just end up calling set_deadline on a chain, potenetially
>>> resulting in recursion? Also I don't think this should ever happen, why
>>> did you add that?
>> Tbh the fence-chain was the part I was a bit fuzzy about, and the main
>> reason I added igt tests.  The iteration is similar to how, for ex,
>> dma_fence_chain_signaled() work, and according to the igt test it does
>> what was intended
> Huh indeed. Maybe something we should fix, like why does the
> dma_fence_chain_for_each not give you the upcast chain pointer ... I guess
> this also needs more Christian and less me.

Yeah I was also already thinking about having a 
dma_fence_chain_for_each_contained() macro which directly returns the 
containing fence, just didn't had time to implement/clean that up.

And yes the patch is correct as it is and avoid the recursion, so 
Reviewed-by: Christian König <christian.koenig@amd.com> for this one.

Regards,
Christian.

> -Daniel
>
>> BR,
>> -R
>>
>>> -Daniel
>>>
>>>> +
>>>> +             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,
>>>> @@ -215,6 +227,7 @@ 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);
>>>>
>>>> --
>>>> 2.31.1
>>>>
>>> --
>>> Daniel Vetter
>>> Software Engineer, Intel Corporation
>>> http://blog.ffwll.ch
diff mbox series

Patch

diff --git a/drivers/dma-buf/dma-fence-chain.c b/drivers/dma-buf/dma-fence-chain.c
index 1b4cb3e5cec9..736a9ad3ea6d 100644
--- a/drivers/dma-buf/dma-fence-chain.c
+++ b/drivers/dma-buf/dma-fence-chain.c
@@ -208,6 +208,18 @@  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;
+
+		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,
@@ -215,6 +227,7 @@  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);