[PATCH v3] drm/i915/gvt: clear the vGPU reset logic

[Du, Changbin]

On Tue, Feb 21, 2017 at 01:37:39PM +0800, Ping Gao wrote:
> Releasing shadow PPGTT pages is not enough when vGPU reset, the
> guest page table tracking data should has same life-cycle with
> all the shadow PPGTT pages; Otherwise there is no chance to
> re-shadow the PPGTT pages without free the guest page table
> tracking data.
> 
> This patch clear the PPGTT reset logic and make the vGPU reset in
> working order.
> 
> v2: refactor some logic to avoid code duplicated.
> v3: remove useless macro and add comments from Christophe.
> 
> Signed-off-by: Ping Gao <ping.a.gao at intel.com>
> ---
>  drivers/gpu/drm/i915/gvt/gtt.c | 39 ++++++++++++++++++++++++++++-----------
>  1 file changed, 28 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/gvt/gtt.c b/drivers/gpu/drm/i915/gvt/gtt.c
> index 28c9234..acd02f7 100644
> --- a/drivers/gpu/drm/i915/gvt/gtt.c
> +++ b/drivers/gpu/drm/i915/gvt/gtt.c
> @@ -2015,6 +2015,22 @@ int intel_vgpu_init_gtt(struct intel_vgpu *vgpu)
>  	return create_scratch_page_tree(vgpu);
>  }
>  
> +static void intel_vgpu_free_mm(struct intel_vgpu *vgpu, int type)
> +{
> +	struct list_head *pos, *n;
> +	struct intel_vgpu_mm *mm;
> +
> +	list_for_each_safe(pos, n, &vgpu->gtt.mm_list_head) {
> +		mm = container_of(pos, struct intel_vgpu_mm, list);
A list_for_each_entry_safe can be used here. :)

> +		if (mm->type == type) {
> +			vgpu->gvt->gtt.mm_free_page_table(mm);
> +			list_del(&mm->list);
> +			list_del(&mm->lru_list);
> +			kfree(mm);
> +		}
> +	}
> +}
> +
>  /**
>   * intel_vgpu_clean_gtt - clean up per-vGPU graphics memory virulization
>   * @vgpu: a vGPU
> @@ -2027,18 +2043,18 @@ int intel_vgpu_init_gtt(struct intel_vgpu *vgpu)
>   */
>  void intel_vgpu_clean_gtt(struct intel_vgpu *vgpu)
>  {
> -	struct list_head *pos, *n;
> -	struct intel_vgpu_mm *mm;
> -
>  	ppgtt_free_all_shadow_page(vgpu);
> -	release_scratch_page_tree(vgpu);
>  
> -	list_for_each_safe(pos, n, &vgpu->gtt.mm_list_head) {
> -		mm = container_of(pos, struct intel_vgpu_mm, list);
> -		vgpu->gvt->gtt.mm_free_page_table(mm);
> -		list_del(&mm->list);
> -		list_del(&mm->lru_list);
> -		kfree(mm);
> +	/* Shadow pages are only created when there is no page
> +	 * table tracking data, so remove page tracking data after
> +	 * removing the shadow pages.This comment is for vGPU reset
> +	 * path.
> +	 */
> +	intel_vgpu_free_mm(vgpu, INTEL_GVT_MM_PPGTT);
> +
> +	if (vgpu->resetting == false) {
> +		intel_vgpu_free_mm(vgpu, INTEL_GVT_MM_GGTT);
> +		release_scratch_page_tree(vgpu);
>  	}
This func may read a little confusing. It try to mix reset work with
clean work, while the name is 'clean'. How about leave
intel_vgpu_clean_gtt just do clean work, and add below 2 statements
into intel_vgpu_reset_gtt()?
  ppgtt_free_all_shadow_page(vgpu);
  intel_vgpu_free_mm(vgpu, INTEL_GVT_MM_PPGTT);

This is more clear for me.


>  }
>  
> @@ -2321,7 +2337,8 @@ void intel_vgpu_reset_gtt(struct intel_vgpu *vgpu, bool dmlr)
>  {
>  	int i;
>  
> -	ppgtt_free_all_shadow_page(vgpu);
> +	intel_vgpu_clean_gtt(vgpu);
> +
>  	if (!dmlr)
>  		return;
>  
> -- 
> 2.7.4
> 
> _______________________________________________
> intel-gvt-dev mailing list
> intel-gvt-dev at lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/intel-gvt-dev

-- 
Thanks,
Changbin Du
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 473 bytes
Desc: not available
URL: <https://lists.freedesktop.org/archives/intel-gvt-dev/attachments/20170221/dba0fd09/attachment.sig>