On Wed, Dec 09, 2015 at 09:30:42AM -0800, Jesse Barnes wrote: > On 12/09/2015 09:10 AM, Chris Wilson wrote: > > Make sure that the RPS bottom-half is flushed before we set the idle > > frequency when we decide the GPU is idle. This should prevent any races > > with the bottom-half and setting the idle frequency, and ensures that > > the bottom-half is bounded by the GPU's rpm reference taken for when it > > is active (i.e. between gen6_rps_busy() and gen6_rps_idle()). > > > > Signed-off-by: Chris Wilson <ch...@chris-wilson.co.uk> > > Cc: Imre Deak <imre.d...@intel.com> > > --- > > drivers/gpu/drm/i915/intel_pm.c | 8 ++++++-- > > 1 file changed, 6 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/gpu/drm/i915/intel_pm.c > > b/drivers/gpu/drm/i915/intel_pm.c > > index e655321385e2..bb796d4e9a3a 100644 > > --- a/drivers/gpu/drm/i915/intel_pm.c > > +++ b/drivers/gpu/drm/i915/intel_pm.c > > @@ -4401,11 +4401,15 @@ void gen6_rps_busy(struct drm_i915_private > > *dev_priv) > > > > void gen6_rps_idle(struct drm_i915_private *dev_priv) > > { > > - struct drm_device *dev = dev_priv->dev; > > + /* Flush our bottom-half so that it does not race with us > > + * setting the idle frequency and so that it is bounded by > > + * our rpm wakeref. > > + */ > > + flush_work(&dev_priv->rps.work); > > > > mutex_lock(&dev_priv->rps.hw_lock); > > if (dev_priv->rps.enabled) { > > - if (IS_VALLEYVIEW(dev)) > > + if (IS_VALLEYVIEW(dev_priv)) > > vlv_set_rps_idle(dev_priv); > > else > > gen6_set_rps(dev_priv->dev, dev_priv->rps.idle_freq); > > > > Hah and a consistency fix snuck in there... nice.
TIL one cannot flush work from inside a workqueue. The good news is we can quite happily squash our usage of i915_wq and just use the regular system_wq. -Chris -- Chris Wilson, Intel Open Source Technology Centre _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/intel-gfx