[PATCH] coding-style: Add guidance to prefer dev_dbg

[PATCH] coding-style: Add guidance to prefer dev_dbg

[Abhishek Pandit-Subedi]

During review, it was suggested that drivers only emit messages when
something is wrong or it is a debug message. Document this as a formal
recommendation.

https://lore.kernel.org/linux-usb/2024012525-alienate-frown-916b@gregkh/

Signed-off-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
---
I'm sending up the change to documentation while this is still fresh.
Will send an update to checkpatch.pl afterwards.

 Documentation/process/coding-style.rst | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/Documentation/process/coding-style.rst b/Documentation/process/coding-style.rst
index c48382c6b477..f8ec23fa89bc 100644
--- a/Documentation/process/coding-style.rst
+++ b/Documentation/process/coding-style.rst
@@ -899,7 +899,8 @@ which you should use to make sure messages are matched to the right device
 and driver, and are tagged with the right level:  dev_err(), dev_warn(),
 dev_info(), and so forth.  For messages that aren't associated with a
 particular device, <linux/printk.h> defines pr_notice(), pr_info(),
-pr_warn(), pr_err(), etc.
+pr_warn(), pr_err(), etc. When drivers are working properly they are quiet,
+so prefer to use dev_dbg/pr_debug unless something is wrong.
 
 Coming up with good debugging messages can be quite a challenge; and once
 you have them, they can be a huge help for remote troubleshooting.  However
-- 
2.43.0.429.g432eaa2c6b-goog

Re: [PATCH] coding-style: Add guidance to prefer dev_dbg

[Greg KH]

On Thu, Jan 25, 2024 at 04:53:11PM -0800, Abhishek Pandit-Subedi wrote:
> During review, it was suggested that drivers only emit messages when
> something is wrong or it is a debug message. Document this as a formal
> recommendation.
> 
> https://lore.kernel.org/linux-usb/2024012525-alienate-frown-916b@gregkh/
> 
> Signed-off-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Re: [PATCH] coding-style: Add guidance to prefer dev_dbg

[Jonathan Corbet]

Abhishek Pandit-Subedi <abhishekpandit@chromium.org> writes:

> During review, it was suggested that drivers only emit messages when
> something is wrong or it is a debug message. Document this as a formal
> recommendation.
>
> https://lore.kernel.org/linux-usb/2024012525-alienate-frown-916b@gregkh/
>
> Signed-off-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
> ---
> I'm sending up the change to documentation while this is still fresh.
> Will send an update to checkpatch.pl afterwards.
>
>  Documentation/process/coding-style.rst | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/Documentation/process/coding-style.rst b/Documentation/process/coding-style.rst
> index c48382c6b477..f8ec23fa89bc 100644
> --- a/Documentation/process/coding-style.rst
> +++ b/Documentation/process/coding-style.rst
> @@ -899,7 +899,8 @@ which you should use to make sure messages are matched to the right device
>  and driver, and are tagged with the right level:  dev_err(), dev_warn(),
>  dev_info(), and so forth.  For messages that aren't associated with a
>  particular device, <linux/printk.h> defines pr_notice(), pr_info(),
> -pr_warn(), pr_err(), etc.
> +pr_warn(), pr_err(), etc. When drivers are working properly they are quiet,
> +so prefer to use dev_dbg/pr_debug unless something is wrong.
>  

Applied, thanks.

jon