On Tue, Jul 05, 2016 at 10:25:12AM +0200, Peter Zijlstra wrote: > On Tue, Jul 05, 2016 at 01:53:03PM +1000, Stephen Rothwell wrote: > > diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c > > index d3502c0603e5..1f91f187b2a8 100644 > > --- a/drivers/gpu/drm/i915/i915_gem.c > > +++ b/drivers/gpu/drm/i915/i915_gem.c > > @@ -3290,7 +3290,7 @@ i915_gem_retire_work_handler(struct work_struct *work) > > * We do not need to do this test under locking as in the worst-case > > * we queue the retire worker once too often. > > */ > > - if (lockless_dereference(dev_priv->gt.awake)) > > + if (/*lockless_dereference*/(dev_priv->gt.awake)) > > queue_delayed_work(dev_priv->wq, > > &dev_priv->gt.retire_work, > > round_jiffies_up_relative(HZ)); > > diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c > > index f6de8dd567a2..2c1926418691 100644 > > --- a/drivers/gpu/drm/i915/i915_irq.c > > +++ b/drivers/gpu/drm/i915/i915_irq.c > > @@ -3095,7 +3095,7 @@ static void i915_hangcheck_elapsed(struct work_struct *work) > > if (!i915.enable_hangcheck) > > return; > > > > - if (!lockless_dereference(dev_priv->gt.awake)) > > + if (!/*lockless_dereference*/(dev_priv->gt.awake)) > > return; > > > > /* As enabling the GPU requires fairly extensive mmio access, > > Right, neither case appears to include a data dependency and thus > lockless_dereference() seems misguided. Agreed! At first glance, this code wants READ_ONCE() rather than lockless_dereference(). Thanx, Paul -- To unsubscribe from this list: send the line "unsubscribe linux-next" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html