[Intel-gfx] [PATCH 2/2] drm/i915: Context objects can never be active when freed

[Chris Wilson]

Quoting Tvrtko Ursulin (2018-06-25 11:42:27)
> 
> On 25/06/2018 11:06, Chris Wilson wrote:
> > Due to how we only release the pining on the context state on
> > retirement and never track activity on the context vma itself, the
> > object can never be active at the point of release. Replace the
> > conditional transfer of ownership onto an active-reference with an
> > assert that the object is idle.
> > 
> > Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> > Cc: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
> > ---
> >   drivers/gpu/drm/i915/intel_lrc.c        | 4 +++-
> >   drivers/gpu/drm/i915/intel_ringbuffer.c | 7 +++++--
> >   2 files changed, 8 insertions(+), 3 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
> > index 97460ee25b7d..2b21a6596360 100644
> > --- a/drivers/gpu/drm/i915/intel_lrc.c
> > +++ b/drivers/gpu/drm/i915/intel_lrc.c
> > @@ -1343,7 +1343,9 @@ static void execlists_context_destroy(struct intel_context *ce)
> >               return;
> >   
> >       intel_ring_free(ce->ring);
> > -     __i915_gem_object_release_unless_active(ce->state->obj);
> > +
> > +     GEM_BUG_ON(i915_gem_object_is_active(ce->state->obj));
> > +     i915_gem_object_put(ce->state->obj);
> >   }
> >   
> >   static void execlists_context_unpin(struct intel_context *ce)
> > diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
> > index e0448eff12bd..700f94c371b3 100644
> > --- a/drivers/gpu/drm/i915/intel_ringbuffer.c
> > +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
> > @@ -1169,8 +1169,11 @@ static void intel_ring_context_destroy(struct intel_context *ce)
> >   {
> >       GEM_BUG_ON(ce->pin_count);
> >   
> > -     if (ce->state)
> > -             __i915_gem_object_release_unless_active(ce->state->obj);
> > +     if (!ce->state)
> > +             return;
> > +
> > +     GEM_BUG_ON(i915_gem_object_is_active(ce->state->obj));
> > +     i915_gem_object_put(ce->state->obj);
> >   }
> >   
> >   static int __context_pin_ppgtt(struct i915_gem_context *ctx)
> > 
> 
> Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin at intel.com>

Thanks for the review, pushed. If I remember, I should poke Zhao for an
updated patch!
-Chris