diff mbox

drm/i915: Don't use a special stolen reserve offset

Message ID 1372966935-18966-1-git-send-email-ben@bwidawsk.net (mailing list archive)
State New, archived
Headers show

Commit Message

Ben Widawsky July 4, 2013, 7:42 p.m. UTC
Setting the node directly is good enough. We don't need a special value
to store the gtt_offset, and we no longer have the pointer to tuck
things away neatly.

This is temporarily broken since:
commit 7dedae28b41000539b6c18bcf72107c97e4937e4
Author: Ben Widawsky <ben@bwidawsk.net>
Date:   Wed Jul 3 14:45:24 2013 -0700

    drm/i915: Use gtt_space->start for stolen reservation

However with no userspace currently, the bisection problem shouldn't be
a concern.

CC: Chris Wilson <chris@chris-wilson.co.uk>
Reported-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
---
 drivers/gpu/drm/i915/i915_drv.h        | 1 -
 drivers/gpu/drm/i915/i915_gem_gtt.c    | 1 -
 drivers/gpu/drm/i915/i915_gem_stolen.c | 8 ++++++--
 3 files changed, 6 insertions(+), 4 deletions(-)

Comments

Daniel Vetter July 4, 2013, 9:24 p.m. UTC | #1
On Thu, Jul 04, 2013 at 12:42:15PM -0700, Ben Widawsky wrote:
> Setting the node directly is good enough. We don't need a special value
> to store the gtt_offset, and we no longer have the pointer to tuck
> things away neatly.
> 
> This is temporarily broken since:
> commit 7dedae28b41000539b6c18bcf72107c97e4937e4
> Author: Ben Widawsky <ben@bwidawsk.net>
> Date:   Wed Jul 3 14:45:24 2013 -0700
> 
>     drm/i915: Use gtt_space->start for stolen reservation
> 
> However with no userspace currently, the bisection problem shouldn't be
> a concern.
> 
> CC: Chris Wilson <chris@chris-wilson.co.uk>
> Reported-by: Daniel Vetter <daniel.vetter@ffwll.ch>
> Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
> ---
>  drivers/gpu/drm/i915/i915_drv.h        | 1 -
>  drivers/gpu/drm/i915/i915_gem_gtt.c    | 1 -
>  drivers/gpu/drm/i915/i915_gem_stolen.c | 8 ++++++--
>  3 files changed, 6 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index ea86ad6..b9e8ba1 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -1201,7 +1201,6 @@ enum hdmi_force_audio {
>  	HDMI_AUDIO_ON,			/* force turn on HDMI audio */
>  };
>  
> -#define I915_GTT_RESERVED (ULONG_MAX)
>  #define I915_GTT_OFFSET_NONE ((u32)-1)
>  
>  struct drm_i915_gem_object_ops {
> diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
> index f075831..c0ca103 100644
> --- a/drivers/gpu/drm/i915/i915_gem_gtt.c
> +++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
> @@ -632,7 +632,6 @@ void i915_gem_setup_global_gtt(struct drm_device *dev,
>  		DRM_DEBUG_KMS("reserving preallocated space: %lx + %zx\n",
>  			      i915_gem_obj_ggtt_offset(obj), obj->base.size);
>  
> -		BUG_ON(obj->gtt_space->start != I915_GTT_RESERVED);

I've thought we've agreed on a WARN_ON(!drm_mm_node_allocated); here?
-Daniel

>  		obj->gtt_space = drm_mm_create_block(&dev_priv->mm.gtt_space,
>  						     i915_gem_obj_ggtt_offset(obj),
>  						     obj->base.size,
> diff --git a/drivers/gpu/drm/i915/i915_gem_stolen.c b/drivers/gpu/drm/i915/i915_gem_stolen.c
> index c6b70312..289d511d 100644
> --- a/drivers/gpu/drm/i915/i915_gem_stolen.c
> +++ b/drivers/gpu/drm/i915/i915_gem_stolen.c
> @@ -397,8 +397,12 @@ i915_gem_object_create_stolen_for_preallocated(struct drm_device *dev,
>  			drm_gem_object_unreference(&obj->base);
>  			return NULL;
>  		}
> -	} else
> -		obj->gtt_space->start = I915_GTT_RESERVED;
> +	} else {
> +		/* Generally it isn't safe to directly set attributes of the
> +		 * drm_mm_node, however this is a special case where we'll
> +		 * promise to handle everything properly later. */
> +		obj->gtt_space->start = gtt_offset;
> +	}
>  
>  	obj->has_global_gtt_mapping = 1;
>  
> -- 
> 1.8.3.2
> 
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx@lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/intel-gfx
Daniel Vetter July 5, 2013, 7:12 a.m. UTC | #2
On Thu, Jul 04, 2013 at 11:24:46PM +0200, Daniel Vetter wrote:
> On Thu, Jul 04, 2013 at 12:42:15PM -0700, Ben Widawsky wrote:
> > Setting the node directly is good enough. We don't need a special value
> > to store the gtt_offset, and we no longer have the pointer to tuck
> > things away neatly.
> > 
> > This is temporarily broken since:
> > commit 7dedae28b41000539b6c18bcf72107c97e4937e4
> > Author: Ben Widawsky <ben@bwidawsk.net>
> > Date:   Wed Jul 3 14:45:24 2013 -0700
> > 
> >     drm/i915: Use gtt_space->start for stolen reservation
> > 
> > However with no userspace currently, the bisection problem shouldn't be
> > a concern.
> > 
> > CC: Chris Wilson <chris@chris-wilson.co.uk>
> > Reported-by: Daniel Vetter <daniel.vetter@ffwll.ch>
> > Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
> > ---
> >  drivers/gpu/drm/i915/i915_drv.h        | 1 -
> >  drivers/gpu/drm/i915/i915_gem_gtt.c    | 1 -
> >  drivers/gpu/drm/i915/i915_gem_stolen.c | 8 ++++++--
> >  3 files changed, 6 insertions(+), 4 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> > index ea86ad6..b9e8ba1 100644
> > --- a/drivers/gpu/drm/i915/i915_drv.h
> > +++ b/drivers/gpu/drm/i915/i915_drv.h
> > @@ -1201,7 +1201,6 @@ enum hdmi_force_audio {
> >  	HDMI_AUDIO_ON,			/* force turn on HDMI audio */
> >  };
> >  
> > -#define I915_GTT_RESERVED (ULONG_MAX)
> >  #define I915_GTT_OFFSET_NONE ((u32)-1)
> >  
> >  struct drm_i915_gem_object_ops {
> > diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
> > index f075831..c0ca103 100644
> > --- a/drivers/gpu/drm/i915/i915_gem_gtt.c
> > +++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
> > @@ -632,7 +632,6 @@ void i915_gem_setup_global_gtt(struct drm_device *dev,
> >  		DRM_DEBUG_KMS("reserving preallocated space: %lx + %zx\n",
> >  			      i915_gem_obj_ggtt_offset(obj), obj->base.size);
> >  
> > -		BUG_ON(obj->gtt_space->start != I915_GTT_RESERVED);
> 
> I've thought we've agreed on a WARN_ON(!drm_mm_node_allocated); here?

WARN_ON(drm_mm_node_allocated); to be precise ;-)
-Daniel
Ben Widawsky July 5, 2013, 7:12 p.m. UTC | #3
On Fri, Jul 05, 2013 at 09:12:05AM +0200, Daniel Vetter wrote:
> On Thu, Jul 04, 2013 at 11:24:46PM +0200, Daniel Vetter wrote:
> > On Thu, Jul 04, 2013 at 12:42:15PM -0700, Ben Widawsky wrote:
> > > Setting the node directly is good enough. We don't need a special value
> > > to store the gtt_offset, and we no longer have the pointer to tuck
> > > things away neatly.
> > > 
> > > This is temporarily broken since:
> > > commit 7dedae28b41000539b6c18bcf72107c97e4937e4
> > > Author: Ben Widawsky <ben@bwidawsk.net>
> > > Date:   Wed Jul 3 14:45:24 2013 -0700
> > > 
> > >     drm/i915: Use gtt_space->start for stolen reservation
> > > 
> > > However with no userspace currently, the bisection problem shouldn't be
> > > a concern.
> > > 
> > > CC: Chris Wilson <chris@chris-wilson.co.uk>
> > > Reported-by: Daniel Vetter <daniel.vetter@ffwll.ch>
> > > Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
> > > ---
> > >  drivers/gpu/drm/i915/i915_drv.h        | 1 -
> > >  drivers/gpu/drm/i915/i915_gem_gtt.c    | 1 -
> > >  drivers/gpu/drm/i915/i915_gem_stolen.c | 8 ++++++--
> > >  3 files changed, 6 insertions(+), 4 deletions(-)
> > > 
> > > diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> > > index ea86ad6..b9e8ba1 100644
> > > --- a/drivers/gpu/drm/i915/i915_drv.h
> > > +++ b/drivers/gpu/drm/i915/i915_drv.h
> > > @@ -1201,7 +1201,6 @@ enum hdmi_force_audio {
> > >  	HDMI_AUDIO_ON,			/* force turn on HDMI audio */
> > >  };
> > >  
> > > -#define I915_GTT_RESERVED (ULONG_MAX)
> > >  #define I915_GTT_OFFSET_NONE ((u32)-1)
> > >  
> > >  struct drm_i915_gem_object_ops {
> > > diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
> > > index f075831..c0ca103 100644
> > > --- a/drivers/gpu/drm/i915/i915_gem_gtt.c
> > > +++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
> > > @@ -632,7 +632,6 @@ void i915_gem_setup_global_gtt(struct drm_device *dev,
> > >  		DRM_DEBUG_KMS("reserving preallocated space: %lx + %zx\n",
> > >  			      i915_gem_obj_ggtt_offset(obj), obj->base.size);
> > >  
> > > -		BUG_ON(obj->gtt_space->start != I915_GTT_RESERVED);
> > 
> > I've thought we've agreed on a WARN_ON(!drm_mm_node_allocated); here?
> 
> WARN_ON(drm_mm_node_allocated); to be precise ;-)
> -Daniel

To be honest, I forgot - but the original plan was to do it after the
node embedding. I think for the same paranoia, we also want to check
that obj->gtt_space != NULL.

Would you mind adding it on merge?
Daniel Vetter July 5, 2013, 7:22 p.m. UTC | #4
On Thu, Jul 04, 2013 at 12:42:15PM -0700, Ben Widawsky wrote:
> Setting the node directly is good enough. We don't need a special value
> to store the gtt_offset, and we no longer have the pointer to tuck
> things away neatly.
> 
> This is temporarily broken since:
> commit 7dedae28b41000539b6c18bcf72107c97e4937e4
> Author: Ben Widawsky <ben@bwidawsk.net>
> Date:   Wed Jul 3 14:45:24 2013 -0700
> 
>     drm/i915: Use gtt_space->start for stolen reservation
> 
> However with no userspace currently, the bisection problem shouldn't be
> a concern.
> 
> CC: Chris Wilson <chris@chris-wilson.co.uk>
> Reported-by: Daniel Vetter <daniel.vetter@ffwll.ch>
> Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
> ---
>  drivers/gpu/drm/i915/i915_drv.h        | 1 -
>  drivers/gpu/drm/i915/i915_gem_gtt.c    | 1 -
>  drivers/gpu/drm/i915/i915_gem_stolen.c | 8 ++++++--
>  3 files changed, 6 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index ea86ad6..b9e8ba1 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -1201,7 +1201,6 @@ enum hdmi_force_audio {
>  	HDMI_AUDIO_ON,			/* force turn on HDMI audio */
>  };
>  
> -#define I915_GTT_RESERVED (ULONG_MAX)
>  #define I915_GTT_OFFSET_NONE ((u32)-1)
>  
>  struct drm_i915_gem_object_ops {
> diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
> index f075831..c0ca103 100644
> --- a/drivers/gpu/drm/i915/i915_gem_gtt.c
> +++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
> @@ -632,7 +632,6 @@ void i915_gem_setup_global_gtt(struct drm_device *dev,
>  		DRM_DEBUG_KMS("reserving preallocated space: %lx + %zx\n",
>  			      i915_gem_obj_ggtt_offset(obj), obj->base.size);
>  
> -		BUG_ON(obj->gtt_space->start != I915_GTT_RESERVED);
>  		obj->gtt_space = drm_mm_create_block(&dev_priv->mm.gtt_space,
>  						     i915_gem_obj_ggtt_offset(obj),
>  						     obj->base.size,
> diff --git a/drivers/gpu/drm/i915/i915_gem_stolen.c b/drivers/gpu/drm/i915/i915_gem_stolen.c
> index c6b70312..289d511d 100644
> --- a/drivers/gpu/drm/i915/i915_gem_stolen.c
> +++ b/drivers/gpu/drm/i915/i915_gem_stolen.c
> @@ -397,8 +397,12 @@ i915_gem_object_create_stolen_for_preallocated(struct drm_device *dev,
>  			drm_gem_object_unreference(&obj->base);
>  			return NULL;
>  		}
> -	} else
> -		obj->gtt_space->start = I915_GTT_RESERVED;
> +	} else {
> +		/* Generally it isn't safe to directly set attributes of the
> +		 * drm_mm_node, however this is a special case where we'll
> +		 * promise to handle everything properly later. */
> +		obj->gtt_space->start = gtt_offset;

Since obj->gtt_space isn't embedded yet this will blow up. I think we need
to do the embedding first, then fix this up.
-Daniel

> +	}
>  
>  	obj->has_global_gtt_mapping = 1;
>  
> -- 
> 1.8.3.2
> 
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx@lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/intel-gfx
diff mbox

Patch

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index ea86ad6..b9e8ba1 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1201,7 +1201,6 @@  enum hdmi_force_audio {
 	HDMI_AUDIO_ON,			/* force turn on HDMI audio */
 };
 
-#define I915_GTT_RESERVED (ULONG_MAX)
 #define I915_GTT_OFFSET_NONE ((u32)-1)
 
 struct drm_i915_gem_object_ops {
diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
index f075831..c0ca103 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
@@ -632,7 +632,6 @@  void i915_gem_setup_global_gtt(struct drm_device *dev,
 		DRM_DEBUG_KMS("reserving preallocated space: %lx + %zx\n",
 			      i915_gem_obj_ggtt_offset(obj), obj->base.size);
 
-		BUG_ON(obj->gtt_space->start != I915_GTT_RESERVED);
 		obj->gtt_space = drm_mm_create_block(&dev_priv->mm.gtt_space,
 						     i915_gem_obj_ggtt_offset(obj),
 						     obj->base.size,
diff --git a/drivers/gpu/drm/i915/i915_gem_stolen.c b/drivers/gpu/drm/i915/i915_gem_stolen.c
index c6b70312..289d511d 100644
--- a/drivers/gpu/drm/i915/i915_gem_stolen.c
+++ b/drivers/gpu/drm/i915/i915_gem_stolen.c
@@ -397,8 +397,12 @@  i915_gem_object_create_stolen_for_preallocated(struct drm_device *dev,
 			drm_gem_object_unreference(&obj->base);
 			return NULL;
 		}
-	} else
-		obj->gtt_space->start = I915_GTT_RESERVED;
+	} else {
+		/* Generally it isn't safe to directly set attributes of the
+		 * drm_mm_node, however this is a special case where we'll
+		 * promise to handle everything properly later. */
+		obj->gtt_space->start = gtt_offset;
+	}
 
 	obj->has_global_gtt_mapping = 1;