[6/9] drm/i915: Add function to determine if a slice has a subslice
diff mbox series

Message ID 20190819215003.48305-7-stuart.summers@intel.com
State New
Headers show
Series
  • Refactor to expand subslice mask (rev 2)
Related show

Commit Message

Stuart Summers Aug. 19, 2019, 9:50 p.m. UTC
Add a new function to determine whether a particular slice
has a given subslice.

Signed-off-by: Stuart Summers <stuart.summers@intel.com>
---
 drivers/gpu/drm/i915/gt/intel_sseu.h     | 10 ++++++++++
 drivers/gpu/drm/i915/intel_device_info.c |  9 ++++-----
 2 files changed, 14 insertions(+), 5 deletions(-)

Comments

Chris Wilson Aug. 20, 2019, 10:53 a.m. UTC | #1
Quoting Stuart Summers (2019-08-19 22:50:00)
> Add a new function to determine whether a particular slice
> has a given subslice.
> 
> Signed-off-by: Stuart Summers <stuart.summers@intel.com>
> ---
>  drivers/gpu/drm/i915/gt/intel_sseu.h     | 10 ++++++++++
>  drivers/gpu/drm/i915/intel_device_info.c |  9 ++++-----
>  2 files changed, 14 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/gt/intel_sseu.h b/drivers/gpu/drm/i915/gt/intel_sseu.h
> index 2261d4e7d98b..0ecc1c35a7a1 100644
> --- a/drivers/gpu/drm/i915/gt/intel_sseu.h
> +++ b/drivers/gpu/drm/i915/gt/intel_sseu.h
> @@ -66,6 +66,16 @@ intel_sseu_from_device_info(const struct sseu_dev_info *sseu)
>         return value;
>  }
>  
> +static inline bool
> +intel_sseu_has_subslice(const struct sseu_dev_info *sseu, int slice,
> +                       int subslice)
> +{
> +       u8 mask = sseu->subslice_mask[slice * sseu->ss_stride +
> +                                     subslice / BITS_PER_BYTE];
> +

Suggestion:

	GEM_BUG_ON(subslice >= sseu->ss_slice);

> +       return mask & BIT(subslice % BITS_PER_BYTE);
> +}

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
-Chris
Stuart Summers Aug. 20, 2019, 7:01 p.m. UTC | #2
On Tue, 2019-08-20 at 11:53 +0100, Chris Wilson wrote:
> Quoting Stuart Summers (2019-08-19 22:50:00)
> > Add a new function to determine whether a particular slice
> > has a given subslice.
> > 
> > Signed-off-by: Stuart Summers <stuart.summers@intel.com>
> > ---
> >  drivers/gpu/drm/i915/gt/intel_sseu.h     | 10 ++++++++++
> >  drivers/gpu/drm/i915/intel_device_info.c |  9 ++++-----
> >  2 files changed, 14 insertions(+), 5 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/gt/intel_sseu.h
> > b/drivers/gpu/drm/i915/gt/intel_sseu.h
> > index 2261d4e7d98b..0ecc1c35a7a1 100644
> > --- a/drivers/gpu/drm/i915/gt/intel_sseu.h
> > +++ b/drivers/gpu/drm/i915/gt/intel_sseu.h
> > @@ -66,6 +66,16 @@ intel_sseu_from_device_info(const struct
> > sseu_dev_info *sseu)
> >         return value;
> >  }
> >  
> > +static inline bool
> > +intel_sseu_has_subslice(const struct sseu_dev_info *sseu, int
> > slice,
> > +                       int subslice)
> > +{
> > +       u8 mask = sseu->subslice_mask[slice * sseu->ss_stride +
> > +                                     subslice / BITS_PER_BYTE];
> > +
> 
> Suggestion:
> 
> 	GEM_BUG_ON(subslice >= sseu->ss_slice);

Thanks Chris and makes sense. I think this should  instead be (ss /
BITS_PER_BYTE >= ss_stride).

I'll post an update hopefully today on this. Let me know if you'd like
me to drop your R-B with the above change.

Thanks,
Stuart

> 
> > +       return mask & BIT(subslice % BITS_PER_BYTE);
> > +}
> 
> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
> -Chris
Chris Wilson Aug. 20, 2019, 7:20 p.m. UTC | #3
Quoting Summers, Stuart (2019-08-20 20:01:05)
> On Tue, 2019-08-20 at 11:53 +0100, Chris Wilson wrote:
> > Quoting Stuart Summers (2019-08-19 22:50:00)
> > > Add a new function to determine whether a particular slice
> > > has a given subslice.
> > > 
> > > Signed-off-by: Stuart Summers <stuart.summers@intel.com>
> > > ---
> > >  drivers/gpu/drm/i915/gt/intel_sseu.h     | 10 ++++++++++
> > >  drivers/gpu/drm/i915/intel_device_info.c |  9 ++++-----
> > >  2 files changed, 14 insertions(+), 5 deletions(-)
> > > 
> > > diff --git a/drivers/gpu/drm/i915/gt/intel_sseu.h
> > > b/drivers/gpu/drm/i915/gt/intel_sseu.h
> > > index 2261d4e7d98b..0ecc1c35a7a1 100644
> > > --- a/drivers/gpu/drm/i915/gt/intel_sseu.h
> > > +++ b/drivers/gpu/drm/i915/gt/intel_sseu.h
> > > @@ -66,6 +66,16 @@ intel_sseu_from_device_info(const struct
> > > sseu_dev_info *sseu)
> > >         return value;
> > >  }
> > >  
> > > +static inline bool
> > > +intel_sseu_has_subslice(const struct sseu_dev_info *sseu, int
> > > slice,
> > > +                       int subslice)
> > > +{
> > > +       u8 mask = sseu->subslice_mask[slice * sseu->ss_stride +
> > > +                                     subslice / BITS_PER_BYTE];
> > > +
> > 
> > Suggestion:
> > 
> >       GEM_BUG_ON(subslice >= sseu->ss_slice);
> 
> Thanks Chris and makes sense. I think this should  instead be (ss /
> BITS_PER_BYTE >= ss_stride).

Don't assume I put more thought into than dropping a hint to catch
programmer errors that would lead to UB. :)

> I'll post an update hopefully today on this. Let me know if you'd like
> me to drop your R-B with the above change.

If CI doesn't explode, keep the r-b ;)
-Chris

Patch
diff mbox series

diff --git a/drivers/gpu/drm/i915/gt/intel_sseu.h b/drivers/gpu/drm/i915/gt/intel_sseu.h
index 2261d4e7d98b..0ecc1c35a7a1 100644
--- a/drivers/gpu/drm/i915/gt/intel_sseu.h
+++ b/drivers/gpu/drm/i915/gt/intel_sseu.h
@@ -66,6 +66,16 @@  intel_sseu_from_device_info(const struct sseu_dev_info *sseu)
 	return value;
 }
 
+static inline bool
+intel_sseu_has_subslice(const struct sseu_dev_info *sseu, int slice,
+			int subslice)
+{
+	u8 mask = sseu->subslice_mask[slice * sseu->ss_stride +
+				      subslice / BITS_PER_BYTE];
+
+	return mask & BIT(subslice % BITS_PER_BYTE);
+}
+
 void intel_sseu_set_info(struct sseu_dev_info *sseu, u8 max_slices,
 			 u8 max_subslices, u8 max_eus_per_subslice);
 
diff --git a/drivers/gpu/drm/i915/intel_device_info.c b/drivers/gpu/drm/i915/intel_device_info.c
index 2320613a51ac..ff3d6508fd17 100644
--- a/drivers/gpu/drm/i915/intel_device_info.c
+++ b/drivers/gpu/drm/i915/intel_device_info.c
@@ -210,10 +210,9 @@  static void gen11_sseu_info_init(struct drm_i915_private *dev_priv)
 			intel_sseu_set_subslices(sseu, s, (ss_en >> ss_idx) &
 							  ss_en_mask);
 
-			for (ss = 0; ss < sseu->max_subslices; ss++) {
-				if (sseu->subslice_mask[s] & BIT(ss))
+			for (ss = 0; ss < sseu->max_subslices; ss++)
+				if (intel_sseu_has_subslice(sseu, s, ss))
 					sseu_set_eus(sseu, s, ss, eu_en);
-			}
 		}
 	}
 	sseu->eu_per_subslice = hweight8(eu_en);
@@ -395,7 +394,7 @@  static void gen9_sseu_info_init(struct drm_i915_private *dev_priv)
 			int eu_per_ss;
 			u8 eu_disabled_mask;
 
-			if (!(sseu->subslice_mask[s] & BIT(ss)))
+			if (!intel_sseu_has_subslice(sseu, s, ss))
 				/* skip disabled subslice */
 				continue;
 
@@ -501,7 +500,7 @@  static void broadwell_sseu_info_init(struct drm_i915_private *dev_priv)
 			u8 eu_disabled_mask;
 			u32 n_disabled;
 
-			if (!(sseu->subslice_mask[s] & BIT(ss)))
+			if (!intel_sseu_has_subslice(sseu, s, ss))
 				/* skip disabled subslice */
 				continue;