Re: [REVIEW PATCH 2/2] vb2-dma-sg: add debug module option.

[Marek Szyprowski <m.szyprowski@samsung.com>]

Hello,

On 3/8/2013 10:21 AM, Hans Verkuil wrote:
> From: Hans Verkuil <hans.verkuil@cisco.com>
>
> This prevents the kernel log from being spammed with these messages.
> By turning on the debug option you will see them again.
>
> Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>

Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>

> ---
>   drivers/media/v4l2-core/videobuf2-dma-sg.c |   17 +++++++++++++----
>   1 file changed, 13 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/media/v4l2-core/videobuf2-dma-sg.c b/drivers/media/v4l2-core/videobuf2-dma-sg.c
> index 952776f..59522b2 100644
> --- a/drivers/media/v4l2-core/videobuf2-dma-sg.c
> +++ b/drivers/media/v4l2-core/videobuf2-dma-sg.c
> @@ -21,6 +21,15 @@
>   #include <media/videobuf2-memops.h>
>   #include <media/videobuf2-dma-sg.h>
>   
> +static int debug;
> +module_param(debug, int, 0644);
> +
> +#define dprintk(level, fmt, arg...)					\
> +	do {								\
> +		if (debug >= level)					\
> +			printk(KERN_DEBUG "vb2-dma-sg: " fmt, ## arg);	\
> +	} while (0)
> +
>   struct vb2_dma_sg_buf {
>   	void				*vaddr;
>   	struct page			**pages;
> @@ -74,7 +83,7 @@ static void *vb2_dma_sg_alloc(void *alloc_ctx, unsigned long size, gfp_t gfp_fla
>   
>   	atomic_inc(&buf->refcount);
>   
> -	printk(KERN_DEBUG "%s: Allocated buffer of %d pages\n",
> +	dprintk(1, "%s: Allocated buffer of %d pages\n",
>   		__func__, buf->sg_desc.num_pages);
>   	return buf;
>   
> @@ -97,7 +106,7 @@ static void vb2_dma_sg_put(void *buf_priv)
>   	int i = buf->sg_desc.num_pages;
>   
>   	if (atomic_dec_and_test(&buf->refcount)) {
> -		printk(KERN_DEBUG "%s: Freeing buffer of %d pages\n", __func__,
> +		dprintk(1, "%s: Freeing buffer of %d pages\n", __func__,
>   			buf->sg_desc.num_pages);
>   		if (buf->vaddr)
>   			vm_unmap_ram(buf->vaddr, buf->sg_desc.num_pages);
> @@ -163,7 +172,7 @@ static void *vb2_dma_sg_get_userptr(void *alloc_ctx, unsigned long vaddr,
>   	return buf;
>   
>   userptr_fail_get_user_pages:
> -	printk(KERN_DEBUG "get_user_pages requested/got: %d/%d]\n",
> +	dprintk(1, "get_user_pages requested/got: %d/%d]\n",
>   	       num_pages_from_user, buf->sg_desc.num_pages);
>   	while (--num_pages_from_user >= 0)
>   		put_page(buf->pages[num_pages_from_user]);
> @@ -186,7 +195,7 @@ static void vb2_dma_sg_put_userptr(void *buf_priv)
>   	struct vb2_dma_sg_buf *buf = buf_priv;
>   	int i = buf->sg_desc.num_pages;
>   
> -	printk(KERN_DEBUG "%s: Releasing userspace buffer of %d pages\n",
> +	dprintk(1, "%s: Releasing userspace buffer of %d pages\n",
>   	       __func__, buf->sg_desc.num_pages);
>   	if (buf->vaddr)
>   		vm_unmap_ram(buf->vaddr, buf->sg_desc.num_pages);

Best regards
-- 
Marek Szyprowski
Samsung Poland R&D Center