Re: [PATCH V3] media: stk1160: Fixed high volume of stk1160_dbg messages

[Greg KH <gregkh@linuxfoundation.org>]

On Sat, Nov 25, 2023 at 01:07:38PM +0530, Ghanshyam Agrawal wrote:
> The function stk1160_dbg gets called too many times, which causes
> the output to get flooded with messages. Since stk1160_dbg uses
> printk, it is now replaced with printk_ratelimited directly.
> 
> Suggested-by: Phillip Potter <phil@philpotter.co.uk>
> Signed-off-by: Ghanshyam Agrawal <ghanshyam1898@gmail.com>
> ---
> V3:
> Fixed the issue with my patch needing previous versions being applied
> first.
> 
> Used printk_ratelimited instead of dev_warn_ratelimited because
> of compiler error "incompatible pointer type".
> 
> V2:
> To add KERN_WARNING in printk_ratelimited, and later as per warning by
> the checkpatch script, replaced  printk_ratelimited with 
> dev_warn_ratelimited.
> 
> V1:
> The function stk1160_dbg gets called too many times, which causes
> the output to get flooded with messages. Since stk1160_dbg uses
> printk, it is now replaced with dev_warn_ratelimited.
> 
>  drivers/media/usb/stk1160/stk1160-video.c | 5 ++---
>  1 file changed, 2 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/media/usb/stk1160/stk1160-video.c b/drivers/media/usb/stk1160/stk1160-video.c
> index 4e966f6bf608..98417fa31d70 100644
> --- a/drivers/media/usb/stk1160/stk1160-video.c
> +++ b/drivers/media/usb/stk1160/stk1160-video.c
> @@ -107,8 +107,7 @@ void stk1160_copy_video(struct stk1160 *dev, u8 *src, int len)
>  
>  	/*
>  	 * TODO: These stk1160_dbg are very spammy!
> -	 * We should 1) check why we are getting them
> -	 * and 2) add ratelimit.
> +	 * We should check why we are getting them.
>  	 *
>  	 * UPDATE: One of the reasons (the only one?) for getting these
>  	 * is incorrect standard (mismatch between expected and configured).
> @@ -151,7 +150,7 @@ void stk1160_copy_video(struct stk1160 *dev, u8 *src, int len)
>  
>  	/* Let the bug hunt begin! sanity checks! */
>  	if (lencopy < 0) {
> -		stk1160_dbg("copy skipped: negative lencopy\n");
> +		printk_ratelimited(KERN_WARNING "copy skipped: negative lencopy\n");

You changed a debug message level to a KERN_WARNING level?  That feels
like a step backwards.

thanks,

greg k-h