Re: [PATCH 40/55] drm/i915: Refactor blocking waits

Joonas Lahtinen
2016-07-27T10:40:09Z

On ke, 2016-07-27 at 08:04 +0100, Chris Wilson wrote:
> On Wed, Jul 27, 2016 at 09:04:03AM +0300, Joonas Lahtinen wrote:
> >
> > On ma, 2016-07-25 at 18:32 +0100, Chris Wilson wrote:
> > >
> > > Tidy up the for loops that handle waiting for read/write vs read-only
> > > access.
> > >
> > > Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> > > ---
> > >  drivers/gpu/drm/i915/i915_gem.c | 158 +++++++++++++++++++---------------------
> > >  1 file changed, 75 insertions(+), 83 deletions(-)
> > >
> > > diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
> > > index 3f6b69dcaccb..2d86a0c3f295 100644
> > > --- a/drivers/gpu/drm/i915/i915_gem.c
> > > +++ b/drivers/gpu/drm/i915/i915_gem.c
> > > @@ -1339,6 +1339,23 @@ put_rpm:
> > >   return ret;
> > >  }
> > >
> > > +static void
> > > +i915_gem_object_retire_request(struct drm_i915_gem_object *obj,
> > > +        struct drm_i915_gem_request *req)
> > > +{
> > > + int idx = req->engine->id;
> > > +
> > > + if (i915_gem_active_peek(&obj->last_read[idx],
> > > +  &obj->base.dev->struct_mutex) == req)
> > > + i915_gem_object_retire__read(obj, idx);
> > > + else if (i915_gem_active_peek(&obj->last_write,
> > > +       &obj->base.dev->struct_mutex) == req)
> > > + i915_gem_object_retire__write(obj);
> > If these functions will use same mutex (be it different than
> > struct_mutex) in all invocations, I'd make an alias for it.
> Why? It is written like this to prevent the compiler doing anything when
> not debugging.

What debuggin related is there, could you elborate? (PS. A branch would
help having the big picture clearer).

> -Chris
>
--
Joonas Lahtinen
Open Source Technology Center
Intel Corporation