[Intel-gfx] [PATCH 2/9] drm/i915: Pull waiting on an external dma-fence into its routine

[Mika Kuoppala]

Chris Wilson <chris at chris-wilson.co.uk> writes:

> Quoting Mika Kuoppala (2020-05-08 11:19:25)
>> Chris Wilson <chris at chris-wilson.co.uk> writes:
>> 
>> > As a means for a small code consolidation, but primarily to start
>> > thinking more carefully about internal-vs-external linkage, pull the
>> > pair of i915_sw_fence_await_dma_fence() calls into a common routine.
>> >
>> > Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
>> > ---
>> >  drivers/gpu/drm/i915/i915_request.c | 16 ++++++++++------
>> >  1 file changed, 10 insertions(+), 6 deletions(-)
>> >
>> > diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c
>> > index be2ce9065a29..94189c7d43cd 100644
>> > --- a/drivers/gpu/drm/i915/i915_request.c
>> > +++ b/drivers/gpu/drm/i915/i915_request.c
>> > @@ -1067,6 +1067,14 @@ i915_request_await_request(struct i915_request *to, struct i915_request *from)
>> >       return 0;
>> >  }
>> >  
>> > +static int
>> > +i915_request_await_external(struct i915_request *rq, struct dma_fence *fence)
>> > +{
>> > +     return i915_sw_fence_await_dma_fence(&rq->submit, fence,
>> > +                                          fence->context ? I915_FENCE_TIMEOUT : 0,
>> > +                                          I915_FENCE_GFP);
>> > +}
>> > +
>> >  int
>> >  i915_request_await_dma_fence(struct i915_request *rq, struct dma_fence *fence)
>> >  {
>> > @@ -1114,9 +1122,7 @@ i915_request_await_dma_fence(struct i915_request *rq, struct dma_fence *fence)
>> >               if (dma_fence_is_i915(fence))
>> >                       ret = i915_request_await_request(rq, to_request(fence));
>> >               else
>> > -                     ret = i915_sw_fence_await_dma_fence(&rq->submit, fence,
>> > -                                                         fence->context ? I915_FENCE_TIMEOUT : 0,
>> > -                                                         I915_FENCE_GFP);
>> > +                     ret = i915_request_await_external(rq, fence);
>> 
>> For us (rq, rq), for external (rq, fence).
>> 
>> It looks neat for a reader. But then, how can external fence have
>> a context?
>
> How about s/fence/dma/?

It is fine like it is. I was just so confused that we piggyback our
context along the fence. But yeah this is the fence->context and zero
is a special. (thanks for explaining in irc)

Reviewed-by: Mika Kuoppala <mika.kuoppala at linux.intel.com>

> -Chris