[Intel-gfx] [PATCH v2 2/2] drm/i915: sanitize RPS resetting during GPU reset

[Jani Nikula]

On Thu, 04 Dec 2014, Imre Deak <imre.deak at intel.com> wrote:
> On Thu, 2014-12-04 at 14:58 +0100, Daniel Vetter wrote:
>> On Thu, Dec 04, 2014 at 02:59:32PM +0200, Imre Deak wrote:
>> > Atm, we don't disable RPS interrupts and related work items before
>> > resetting the GPU. This may interfere with the following GPU
>> > initialization and cause RPS interrupts to show up in PM_IIR too early
>> > before calling gen6_enable_rps_interrupts() (triggering a WARN there).
>> > 
>> > Solve this by disabling RPS interrupts and flushing any related work
>> > items before resetting the GPU.
>> > 
>> > v2:
>> > - split out the common parts of the gt suspend and the new gt reset
>> >   functions (Paulo)
>> > 
>> > Reported-by: He, Shuang <shuang.he at intel.com>
>> > Testcase: igt/gem_reset_stats/ban-render
>> > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=86644
>> > Signed-off-by: Imre Deak <imre.deak at intel.com>
>> > ---
>> >  drivers/gpu/drm/i915/i915_drv.c |  5 ++++-
>> >  drivers/gpu/drm/i915/intel_pm.c | 28 +++++++++++++++++++---------
>> >  2 files changed, 23 insertions(+), 10 deletions(-)
>> > 
>> > diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
>> > index 71be3c9..8377249 100644
>> > --- a/drivers/gpu/drm/i915/i915_drv.c
>> > +++ b/drivers/gpu/drm/i915/i915_drv.c
>> > @@ -810,6 +810,9 @@ int i915_reset(struct drm_device *dev)
>> >  	if (!i915.reset)
>> >  		return 0;
>> >  
>> > +	if (drm_core_check_feature(dev, DRIVER_MODESET))
>> > +		intel_reset_gt_powersave(dev);
>> 
>> UMS support is dead, so you can leave this hunk out.
>
> Ok, we can call here intel_reset_gt_powersave() unconditionally.

Imre, are these headed for 3.19 since the original 1/2 is there?

commit 9939fba226649c62630a74d36ee45c5d5402b460
Author: Imre Deak <imre.deak at intel.com>
Date:   Thu Nov 20 23:01:47 2014 +0200

    drm/i915: mask RPS IRQs properly when disabling RPS

Please post the version addressing Daniel's comment.

Thanks,
Jani.



>
>> -Daniel
>> 
>> > +
>> >  	mutex_lock(&dev->struct_mutex);
>> >  
>> >  	i915_gem_reset(dev);
>> > @@ -881,7 +884,7 @@ int i915_reset(struct drm_device *dev)
>> >  		 * of re-init after reset.
>> >  		 */
>> >  		if (INTEL_INFO(dev)->gen > 5)
>> > -			intel_reset_gt_powersave(dev);
>> > +			intel_enable_gt_powersave(dev);
>> >  	} else {
>> >  		mutex_unlock(&dev->struct_mutex);
>> >  	}
>> > diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
>> > index 78911e2..45c786f 100644
>> > --- a/drivers/gpu/drm/i915/intel_pm.c
>> > +++ b/drivers/gpu/drm/i915/intel_pm.c
>> > @@ -6072,6 +6072,20 @@ void intel_cleanup_gt_powersave(struct drm_device *dev)
>> >  		valleyview_cleanup_gt_powersave(dev);
>> >  }
>> >  
>> > +static void gen6_suspend_rps(struct drm_device *dev)
>> > +{
>> > +	struct drm_i915_private *dev_priv = dev->dev_private;
>> > +
>> > +	flush_delayed_work(&dev_priv->rps.delayed_resume_work);
>> > +
>> > +	/*
>> > +	 * TODO: disable RPS interrupts on GEN9+ too once RPS support
>> > +	 * is added for it.
>> > +	 */
>> > +	if (INTEL_INFO(dev)->gen < 9)
>> > +		gen6_disable_rps_interrupts(dev);
>> > +}
>> > +
>> >  /**
>> >   * intel_suspend_gt_powersave - suspend PM work and helper threads
>> >   * @dev: drm device
>> > @@ -6087,14 +6101,7 @@ void intel_suspend_gt_powersave(struct drm_device *dev)
>> >  	if (INTEL_INFO(dev)->gen < 6)
>> >  		return;
>> >  
>> > -	flush_delayed_work(&dev_priv->rps.delayed_resume_work);
>> > -
>> > -	/*
>> > -	 * TODO: disable RPS interrupts on GEN9+ too once RPS support
>> > -	 * is added for it.
>> > -	 */
>> > -	if (INTEL_INFO(dev)->gen < 9)
>> > -		gen6_disable_rps_interrupts(dev);
>> > +	gen6_suspend_rps(dev);
>> >  
>> >  	/* Force GPU to min freq during suspend */
>> >  	gen6_rps_idle(dev_priv);
>> > @@ -6197,8 +6204,11 @@ void intel_reset_gt_powersave(struct drm_device *dev)
>> >  {
>> >  	struct drm_i915_private *dev_priv = dev->dev_private;
>> >  
>> > +	if (INTEL_INFO(dev)->gen < 6)
>> > +		return;
>> > +
>> > +	gen6_suspend_rps(dev);
>> >  	dev_priv->rps.enabled = false;
>> > -	intel_enable_gt_powersave(dev);
>> >  }
>> >  
>> >  static void ibx_init_clock_gating(struct drm_device *dev)
>> > -- 
>> > 1.8.4
>> > 
>> > _______________________________________________
>> > Intel-gfx mailing list
>> > Intel-gfx at lists.freedesktop.org
>> > http://lists.freedesktop.org/mailman/listinfo/intel-gfx
>> 
>
>
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-- 
Jani Nikula, Intel Open Source Technology Center