diff mbox series

[v2,2/3] media: videobuf2-core: reverse the iteration order in __vb2_buf_dmabuf_put

Message ID 20240403091306.1308878-3-yunkec@chromium.org
State New
Headers show
Series media: videobuf2-core: attach once if multiple planes share the same dbuf | expand

Commit Message

Yunke Cao April 3, 2024, 9:13 a.m. UTC 
Release the planes from num_planes - 1 to 0.

Signed-off-by: Yunke Cao <yunkec@chromium.org>
---
 drivers/media/common/videobuf2/videobuf2-core.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

Comments

Hans Verkuil April 24, 2024, 10:24 a.m. UTC | #1 
On 03/04/2024 11:13, Yunke Cao wrote:
> Release the planes from num_planes - 1 to 0.
> 
> Signed-off-by: Yunke Cao <yunkec@chromium.org>
> ---
>  drivers/media/common/videobuf2/videobuf2-core.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/media/common/videobuf2/videobuf2-core.c b/drivers/media/common/videobuf2/videobuf2-core.c
> index 702f7b6f783a..a5368cef73bb 100644
> --- a/drivers/media/common/videobuf2/videobuf2-core.c
> +++ b/drivers/media/common/videobuf2/videobuf2-core.c
> @@ -320,10 +320,10 @@ static void __vb2_plane_dmabuf_put(struct vb2_buffer *vb, struct vb2_plane *p)
>   */
>  static void __vb2_buf_dmabuf_put(struct vb2_buffer *vb)
>  {
> -	unsigned int plane;
> +	unsigned int i;
>  
> -	for (plane = 0; plane < vb->num_planes; ++plane)
> -		__vb2_plane_dmabuf_put(vb, &vb->planes[plane]);
> +	for (i = 0; i < vb->num_planes; ++i)
> +		__vb2_plane_dmabuf_put(vb, &vb->planes[vb->num_planes - 1 - i]);

This is a bit ugly. Why not just do:

	for (plane = vb->num_planes; plane; plane--)
		__vb2_plane_dmabuf_put(vb, &vb->planes[plane - 1]);

Regards,

	Hans

>  }
>  
>  /*
Tomasz Figa May 17, 2024, 11:14 a.m. UTC | #2 
On Wed, Apr 24, 2024 at 12:24:24PM +0200, Hans Verkuil wrote:
> On 03/04/2024 11:13, Yunke Cao wrote:
> > Release the planes from num_planes - 1 to 0.
> > 
> > Signed-off-by: Yunke Cao <yunkec@chromium.org>
> > ---
> >  drivers/media/common/videobuf2/videobuf2-core.c | 6 +++---
> >  1 file changed, 3 insertions(+), 3 deletions(-)
> > 
> > diff --git a/drivers/media/common/videobuf2/videobuf2-core.c b/drivers/media/common/videobuf2/videobuf2-core.c
> > index 702f7b6f783a..a5368cef73bb 100644
> > --- a/drivers/media/common/videobuf2/videobuf2-core.c
> > +++ b/drivers/media/common/videobuf2/videobuf2-core.c
> > @@ -320,10 +320,10 @@ static void __vb2_plane_dmabuf_put(struct vb2_buffer *vb, struct vb2_plane *p)
> >   */
> >  static void __vb2_buf_dmabuf_put(struct vb2_buffer *vb)
> >  {
> > -	unsigned int plane;
> > +	unsigned int i;
> >  
> > -	for (plane = 0; plane < vb->num_planes; ++plane)
> > -		__vb2_plane_dmabuf_put(vb, &vb->planes[plane]);
> > +	for (i = 0; i < vb->num_planes; ++i)
> > +		__vb2_plane_dmabuf_put(vb, &vb->planes[vb->num_planes - 1 - i]);
> 
> This is a bit ugly. Why not just do:
> 
> 	for (plane = vb->num_planes; plane; plane--)
> 		__vb2_plane_dmabuf_put(vb, &vb->planes[plane - 1]);

How about making plane signed (since it's just a local variable) and
avoiding any weird additions or subtractions?

Best regards,
Tomasz
diff mbox series

Patch

diff --git a/drivers/media/common/videobuf2/videobuf2-core.c b/drivers/media/common/videobuf2/videobuf2-core.c
index 702f7b6f783a..a5368cef73bb 100644
--- a/drivers/media/common/videobuf2/videobuf2-core.c
+++ b/drivers/media/common/videobuf2/videobuf2-core.c
@@ -320,10 +320,10 @@  static void __vb2_plane_dmabuf_put(struct vb2_buffer *vb, struct vb2_plane *p)
  */
 static void __vb2_buf_dmabuf_put(struct vb2_buffer *vb)
 {
-	unsigned int plane;
+	unsigned int i;
 
-	for (plane = 0; plane < vb->num_planes; ++plane)
-		__vb2_plane_dmabuf_put(vb, &vb->planes[plane]);
+	for (i = 0; i < vb->num_planes; ++i)
+		__vb2_plane_dmabuf_put(vb, &vb->planes[vb->num_planes - 1 - i]);
 }
 
 /*