Re: [PATCH v2] [media] vb2: include lengths in dmabuf qbuf debug message

From: Javier Martinez Canillas
Date: Wed Jul 20 2016 - 18:57:08 EST


Hello Sakari,

On 07/20/2016 03:52 PM, Sakari Ailus wrote:
> On Wed, Jul 20, 2016 at 12:07:55PM -0400, Javier Martinez Canillas wrote:
>> If the VIDIOC_QBUF ioctl fails due a wrong dmabuf length, it's
>> useful to get the invalid and minimum lengths as a debug info.
>>
>> Before this patch:
>>
>> vb2-core: __qbuf_dmabuf: invalid dmabuf length for plane 1
>>
>> After this patch:
>>
>> vb2-core: __qbuf_dmabuf: invalid dmabuf length 221248 for plane 1, minimum length 410880
>>
>> Signed-off-by: Javier Martinez Canillas <javier@xxxxxxxxxxxxxxx>
>>
>> ---
>>
>> Changes in v2:
>> - Use %u instead of %d (Sakari Ailus)
>> - Include min_length (Sakari Ailus)
>>
>> drivers/media/v4l2-core/videobuf2-core.c | 6 ++++--
>> 1 file changed, 4 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/media/v4l2-core/videobuf2-core.c b/drivers/media/v4l2-core/videobuf2-core.c
>> index b6fbc04f9699..bbba50d6e1ad 100644
>> --- a/drivers/media/v4l2-core/videobuf2-core.c
>> +++ b/drivers/media/v4l2-core/videobuf2-core.c
>> @@ -1227,8 +1227,10 @@ static int __qbuf_dmabuf(struct vb2_buffer *vb, const void *pb)
>> planes[plane].length = dbuf->size;
>>
>> if (planes[plane].length < vb->planes[plane].min_length) {
>> - dprintk(1, "invalid dmabuf length for plane %d\n",
>> - plane);
>> + dprintk(1, "invalid dmabuf length %u for plane %d, "
>> + "minimum length %u\n",
>
> You shouldn't split strings. It breaks grep.
>

Yes I know but if I didn't split the line, it would had been longer than
the max 80 character per line convention. On those situations I follow
what's already done in the file for consistency and most strings in the
videobuf2-core file, whose lines are over 80 characters, are being split.

But if having a longer line is preferred, I'll happily re-spin the patch.

> With that changed,
>
> Acked-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
>
>> + planes[plane].length, plane,
>> + vb->planes[plane].min_length);
>> dma_buf_put(dbuf);
>> ret = -EINVAL;
>> goto err;
>

Best regards,
--
Javier Martinez Canillas
Open Source Group
Samsung Research America