[Intel-gfx] [PATCH 16/40] drm/i915: Pull scheduling under standalone lock

[Chris Wilson]

Quoting Tvrtko Ursulin (2018-09-24 12:19:39)
> 
> On 19/09/2018 20:55, Chris Wilson wrote:
> > diff --git a/drivers/gpu/drm/i915/i915_scheduler.c b/drivers/gpu/drm/i915/i915_scheduler.c
> > new file mode 100644
> > index 000000000000..910ac7089596
> > --- /dev/null
> > +++ b/drivers/gpu/drm/i915/i915_scheduler.c
> > @@ -0,0 +1,377 @@
> > +/*
> > + * SPDX-License-Identifier: MIT
> > + *
> > + * Copyright © 2018 Intel Corporation
> > + */
> > +
> > +#include <linux/mutex.h>
> > +
> > +#include "i915_drv.h"
> > +#include "i915_request.h"
> > +#include "i915_scheduler.h"
> > +
> > +static DEFINE_SPINLOCK(schedule_lock);
> 
> Any good excuses to not put it into device private straight away?

It can't be per-device, since it will need to be global across devices
as the dependency chains may cross devices and we will want to choose an
optimal order globally. That's my goal here, at least.

At some point, the horror of scalability vs priority inversion must then
be tackled. (But for now, I'd rather have priority inheritance and start
from a position of good qos and build scalability on top.)
-Chris