| Message ID | 1432238508-28741-5-git-send-email-chris@chris-wilson.co.uk (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Thu, May 21, 2015 at 09:01:48PM +0100, Chris Wilson wrote: > As Daniel commented on > > commit b7ffe1362c5f468b853223acc9268804aa92afc8 > Author: Chris Wilson <chris@chris-wilson.co.uk> > Date: Mon Apr 27 13:41:24 2015 +0100 > > drm/i915: Free RPS boosts for all laggards > > it is better to be explicit when sharing hardcoded values such as > throttle/boost timeouts. Make it so! > > Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> > Cc: Daniel Vetter <daniel.vetter@ffwll.ch> I merged patch 1&4 from this to dinq. I'd like a "I want this" for 2. And 3 needs more time to properly review the locking and everything, I'll try to do that later today. Thanks, Daniel > --- > drivers/gpu/drm/i915/i915_drv.h | 6 ++++++ > drivers/gpu/drm/i915/i915_gem.c | 2 +- > drivers/gpu/drm/i915/intel_pm.c | 2 +- > 3 files changed, 8 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h > index abd0914b4849..30ffb9138116 100644 > --- a/drivers/gpu/drm/i915/i915_drv.h > +++ b/drivers/gpu/drm/i915/i915_drv.h > @@ -279,6 +279,12 @@ struct drm_i915_file_private { > struct { > spinlock_t lock; > struct list_head request_list; > +/* 20ms is a fairly arbitrary limit (greater than the average frame time) > + * chosen to prevent the CPU getting more than a frame ahead of the GPU > + * (when using lax throttling for the frontbuffer). We also use it to > + * offer free GPU waitboosts for severely congested workloads. > + */ > +#define DRM_I915_THROTTLE_JIFFIES msecs_to_jiffies(20) > } mm; > struct idr context_idr; > > diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c > index ca41fc56f246..9ae98b00ff56 100644 > --- a/drivers/gpu/drm/i915/i915_gem.c > +++ b/drivers/gpu/drm/i915/i915_gem.c > @@ -4211,7 +4211,7 @@ i915_gem_ring_throttle(struct drm_device *dev, struct drm_file *file) > { > struct drm_i915_private *dev_priv = dev->dev_private; > struct drm_i915_file_private *file_priv = file->driver_priv; > - unsigned long recent_enough = jiffies - msecs_to_jiffies(20); > + unsigned long recent_enough = jiffies - DRM_I915_THROTTLE_JIFFIES; > struct drm_i915_gem_request *request, *target = NULL; > unsigned reset_counter; > int ret; > diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c > index 833f9dd28fea..abeb7fca17c8 100644 > --- a/drivers/gpu/drm/i915/intel_pm.c > +++ b/drivers/gpu/drm/i915/intel_pm.c > @@ -4164,7 +4164,7 @@ void gen6_rps_boost(struct drm_i915_private *dev_priv, > /* Force a RPS boost (and don't count it against the client) if > * the GPU is severely congested. > */ > - if (rps && time_after(jiffies, submitted + msecs_to_jiffies(20))) > + if (rps && time_after(jiffies, submitted + DRM_I915_THROTTLE_JIFFIES)) > rps = NULL; > > spin_lock(&dev_priv->rps.client_lock); > -- > 2.1.4 >
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index abd0914b4849..30ffb9138116 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -279,6 +279,12 @@ struct drm_i915_file_private { struct { spinlock_t lock; struct list_head request_list; +/* 20ms is a fairly arbitrary limit (greater than the average frame time) + * chosen to prevent the CPU getting more than a frame ahead of the GPU + * (when using lax throttling for the frontbuffer). We also use it to + * offer free GPU waitboosts for severely congested workloads. + */ +#define DRM_I915_THROTTLE_JIFFIES msecs_to_jiffies(20) } mm; struct idr context_idr; diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index ca41fc56f246..9ae98b00ff56 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -4211,7 +4211,7 @@ i915_gem_ring_throttle(struct drm_device *dev, struct drm_file *file) { struct drm_i915_private *dev_priv = dev->dev_private; struct drm_i915_file_private *file_priv = file->driver_priv; - unsigned long recent_enough = jiffies - msecs_to_jiffies(20); + unsigned long recent_enough = jiffies - DRM_I915_THROTTLE_JIFFIES; struct drm_i915_gem_request *request, *target = NULL; unsigned reset_counter; int ret; diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index 833f9dd28fea..abeb7fca17c8 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -4164,7 +4164,7 @@ void gen6_rps_boost(struct drm_i915_private *dev_priv, /* Force a RPS boost (and don't count it against the client) if * the GPU is severely congested. */ - if (rps && time_after(jiffies, submitted + msecs_to_jiffies(20))) + if (rps && time_after(jiffies, submitted + DRM_I915_THROTTLE_JIFFIES)) rps = NULL; spin_lock(&dev_priv->rps.client_lock);
As Daniel commented on commit b7ffe1362c5f468b853223acc9268804aa92afc8 Author: Chris Wilson <chris@chris-wilson.co.uk> Date: Mon Apr 27 13:41:24 2015 +0100 drm/i915: Free RPS boosts for all laggards it is better to be explicit when sharing hardcoded values such as throttle/boost timeouts. Make it so! Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> --- drivers/gpu/drm/i915/i915_drv.h | 6 ++++++ drivers/gpu/drm/i915/i915_gem.c | 2 +- drivers/gpu/drm/i915/intel_pm.c | 2 +- 3 files changed, 8 insertions(+), 2 deletions(-)