On Mon, Jul 08, 2013 at 11:08:42PM -0700, Ben Widawsky wrote:
> Probably need to squash whole thing, or just the inactive part, tbd...
> 
> Signed-off-by: Ben Widawsky <b...@bwidawsk.net>

I agree that we need vma->active, but I'm not sold on removing
obj->active. Atm we have to use-cases for checking obj->active:
- In the evict/unbind code to check whether the gpu is still using this
  specific mapping. This use-case nicely fits into checking vma->active.
- In the shrinker code and everywhere we want to do cpu access we only
  care about whether the gpu is accessing the object, not at all through
  which mapping precisely. There a vma-independant obj->active sounds much
  saner.

Note though that just keeping track of vma->active isn't too useful, since
if some other vma is keeping the object busy we'll still stall on that one
for eviction. So we'd need a vma->ring and vma->last_rendering_seqno, too.

At that point I wonder a bit whether all this complexity is worth it ...

I need to ponder this some more.
-Daniel

> ---
>  drivers/gpu/drm/i915/i915_drv.h | 14 ++++++------
>  drivers/gpu/drm/i915/i915_gem.c | 47 
> ++++++++++++++++++++++++-----------------
>  2 files changed, 35 insertions(+), 26 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index 38d07f2..e6694ae 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -541,6 +541,13 @@ struct i915_vma {
>       struct drm_i915_gem_object *obj;
>       struct i915_address_space *vm;
>  
> +     /**
> +      * This is set if the object is on the active lists (has pending
> +      * rendering and so a non-zero seqno), and is not set if it i s on
> +      * inactive (ready to be unbound) list.
> +      */
> +     unsigned int active:1;
> +
>       /** This object's place on the active/inactive lists */
>       struct list_head mm_list;
>  
> @@ -1250,13 +1257,6 @@ struct drm_i915_gem_object {
>       struct list_head exec_list;
>  
>       /**
> -      * This is set if the object is on the active lists (has pending
> -      * rendering and so a non-zero seqno), and is not set if it i s on
> -      * inactive (ready to be unbound) list.
> -      */
> -     unsigned int active:1;
> -
> -     /**
>        * This is set if the object has been written to since last bound
>        * to the GTT
>        */
> diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
> index c2ecb78..b87073b 100644
> --- a/drivers/gpu/drm/i915/i915_gem.c
> +++ b/drivers/gpu/drm/i915/i915_gem.c
> @@ -137,7 +137,13 @@ int i915_mutex_lock_interruptible(struct drm_device *dev)
>  /* NB: Not the same as !i915_gem_object_is_inactive */
>  bool i915_gem_object_is_active(struct drm_i915_gem_object *obj)
>  {
> -     return obj->active;
> +     struct i915_vma *vma;
> +
> +     list_for_each_entry(vma, &obj->vma_list, vma_link)
> +             if (vma->active)
> +                     return true;
> +
> +     return false;
>  }
>  
>  static inline bool
> @@ -1899,14 +1905,14 @@ i915_gem_object_move_to_active(struct 
> drm_i915_gem_object *obj,
>       BUG_ON(ring == NULL);
>       obj->ring = ring;
>  
> +     /* Move from whatever list we were on to the tail of execution. */
> +     vma = i915_gem_obj_to_vma(obj, vm);
>       /* Add a reference if we're newly entering the active list. */
> -     if (!i915_gem_object_is_active(obj)) {
> +     if (!vma->active) {
>               drm_gem_object_reference(&obj->base);
> -             obj->active = 1;
> +             vma->active = 1;
>       }
>  
> -     /* Move from whatever list we were on to the tail of execution. */
> -     vma = i915_gem_obj_to_vma(obj, vm);
>       list_move_tail(&vma->mm_list, &vm->active_list);
>       list_move_tail(&obj->ring_list, &ring->active_list);
>  
> @@ -1927,16 +1933,23 @@ i915_gem_object_move_to_active(struct 
> drm_i915_gem_object *obj,
>  }
>  
>  static void
> -i915_gem_object_move_to_inactive(struct drm_i915_gem_object *obj,
> -                              struct i915_address_space *vm)
> +i915_gem_object_move_to_inactive(struct drm_i915_gem_object *obj)
>  {
> +     struct drm_i915_private *dev_priv = obj->base.dev->dev_private;
> +     struct i915_address_space *vm;
>       struct i915_vma *vma;
> +     int i = 0;
>  
>       BUG_ON(obj->base.write_domain & ~I915_GEM_GPU_DOMAINS);
> -     BUG_ON(!i915_gem_object_is_active(obj));
>  
> -     vma = i915_gem_obj_to_vma(obj, vm);
> -     list_move_tail(&vma->mm_list, &vm->inactive_list);
> +     list_for_each_entry(vm, &dev_priv->vm_list, global_link) {
> +             vma = i915_gem_obj_to_vma(obj, vm);
For paranoia we might want to track the vm used to run a batch in it
request struct, then we

> +             if (!vma || !vma->active)
> +                     continue;
> +             list_move_tail(&vma->mm_list, &vm->inactive_list);
> +             vma->active = 0;
> +             i++;
> +     }
>  
>       list_del_init(&obj->ring_list);
>       obj->ring = NULL;
> @@ -1948,8 +1961,8 @@ i915_gem_object_move_to_inactive(struct 
> drm_i915_gem_object *obj,
>       obj->last_fenced_seqno = 0;
>       obj->fenced_gpu_access = false;
>  
> -     obj->active = 0;
> -     drm_gem_object_unreference(&obj->base);
> +     while (i--)
> +             drm_gem_object_unreference(&obj->base);
>  
>       WARN_ON(i915_verify_lists(dev));
>  }
> @@ -2272,15 +2285,13 @@ static void i915_gem_reset_ring_lists(struct 
> drm_i915_private *dev_priv,
>       }
>  
>       while (!list_empty(&ring->active_list)) {
> -             struct i915_address_space *vm;
>               struct drm_i915_gem_object *obj;
>  
>               obj = list_first_entry(&ring->active_list,
>                                      struct drm_i915_gem_object,
>                                      ring_list);
>  
> -             list_for_each_entry(vm, &dev_priv->vm_list, global_link)
> -                     i915_gem_object_move_to_inactive(obj, vm);
> +             i915_gem_object_move_to_inactive(obj);
>       }
>  }
>  
> @@ -2356,8 +2367,6 @@ i915_gem_retire_requests_ring(struct intel_ring_buffer 
> *ring)
>        * by the ringbuffer to the flushing/inactive lists as appropriate.
>        */
>       while (!list_empty(&ring->active_list)) {
> -             struct drm_i915_private *dev_priv = ring->dev->dev_private;
> -             struct i915_address_space *vm;
>               struct drm_i915_gem_object *obj;
>  
>               obj = list_first_entry(&ring->active_list,
> @@ -2367,8 +2376,8 @@ i915_gem_retire_requests_ring(struct intel_ring_buffer 
> *ring)
>               if (!i915_seqno_passed(seqno, obj->last_read_seqno))
>                       break;
>  
> -             list_for_each_entry(vm, &dev_priv->vm_list, global_link)
> -                     i915_gem_object_move_to_inactive(obj, vm);
> +             BUG_ON(!i915_gem_object_is_active(obj));
> +             i915_gem_object_move_to_inactive(obj);
>       }
>  
>       if (unlikely(ring->trace_irq_seqno &&
> -- 
> 1.8.3.2
> 
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx@lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/intel-gfx

-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
http://lists.freedesktop.org/mailman/listinfo/intel-gfx

Reply via email to