[Intel-gfx] [PATCH 21/31] drm/i915: Convert engine->write_tail to operate on a request

[Chris Wilson]

On Thu, Jul 28, 2016 at 09:41:14AM +0300, Joonas Lahtinen wrote:
> On ke, 2016-07-27 at 13:30 +0100, Chris Wilson wrote:
> > On Wed, Jul 27, 2016 at 12:53:25PM +0100, Dave Gordon wrote:
> > > 
> > > On 25/07/16 08:44, Chris Wilson wrote:
> > > > 
> > > > +static void i9xx_submit_request(struct drm_i915_gem_request *request)
> > > > +{
> > > > +	struct drm_i915_private *dev_priv = request->i915;
> > > > +
> > > > +	I915_WRITE_TAIL(request->engine,
> > > > +			request->tail % (request->ring->size - 1));
> > > > +}
> > > Another "modulo ringsize-1" here too.
> > Because the original code included that safe guard against known GPU
> > hangs.
> 
> I think a comment would be justified.

Hmm, I do beg your pardon, at this point in the tree
intel_ring_advance() still exists and is applying the modulus on every
command packet.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre