Re: [PATCH] drm/vgm: replace idr_init() by idr_init_base()

From: Daniel Vetter
Date: Thu Nov 05 2020 - 04:42:21 EST


On Wed, Nov 04, 2020 at 04:53:38PM +0530, Deepak R Varma wrote:
> idr_init() uses base 0 which is an invalid identifier. The new function
> idr_init_base allows IDR to set the ID lookup from base 1. This avoids
> all lookups that otherwise starts from 0 since 0 is always unused.
>
> References: commit 6ce711f27500 ("idr: Make 1-based IDRs more efficient")
>
> Signed-off-by: Deepak R Varma <mh12gx2825@xxxxxxxxx>

Tiny typo in the commit message summary: s/vgm/vgem/

Also can you pls resbumit this with intel-gfx mailing list on cc (like for
i915)? There's a CI bot there which runs a few vgem tests, would be good
to confirm nothing has been broken.

Otherwise lgtm.

Thanks, Daniel

> ---
> drivers/gpu/drm/vgem/vgem_fence.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/vgem/vgem_fence.c b/drivers/gpu/drm/vgem/vgem_fence.c
> index 17f32f550dd9..2902dc6e64fa 100644
> --- a/drivers/gpu/drm/vgem/vgem_fence.c
> +++ b/drivers/gpu/drm/vgem/vgem_fence.c
> @@ -233,7 +233,7 @@ int vgem_fence_signal_ioctl(struct drm_device *dev,
> int vgem_fence_open(struct vgem_file *vfile)
> {
> mutex_init(&vfile->fence_mutex);
> - idr_init(&vfile->fence_idr);
> + idr_init_base(&vfile->fence_idr, 1);
>
> return 0;
> }
> --
> 2.25.1
>

--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch