Re: [PATCH v3 2/2] Add XFS messages to printk index

[Chris Down <chris@xxxxxxxxxxxxxx>]

Jonathan Lassoff writes:
> In order for end users to quickly react to new issues that come up in
> production, it is proving useful to leverage the printk indexing system.
> This printk index enables kernel developers to use calls to printk()
> with changeable ad-hoc format strings, while still enabling end users
> to detect changes from release to release.
>
> So that detailed XFS messages are captures by this printk index, this
> patch wraps the xfs_<level> and xfs_alert_tag functions.
>
> Signed-off-by: Jonathan Lassoff <jof@xxxxxxxxxx>

After Dave's suggested whitespace/ordering fixup, feel free to add:

Reviewed-by: Chris Down <chris@xxxxxxxxxxxxxx>

Thanks!

> ---
>
> Notes:
>    [PATCH v1]
>      * De-duplicate kernel logging levels and tidy whitespace.
>    [PATCH v2]
>      * Split changes into two patches:
>         - function and prototype de-duplication.
>         - Adding printk indexing
>    [PATCH v3]
>      * Fix some whitespace and semicolon. *facepalm*
>
> fs/xfs/xfs_message.c |  2 +-
> fs/xfs/xfs_message.h | 29 ++++++++++++++++++++---------
> 2 files changed, 21 insertions(+), 10 deletions(-)
>
> diff --git a/fs/xfs/xfs_message.c b/fs/xfs/xfs_message.c
> index ede8a4f2f676..f01efad20420 100644
> --- a/fs/xfs/xfs_message.c
> +++ b/fs/xfs/xfs_message.c
> @@ -51,7 +51,7 @@ void xfs_printk_level(
> }
>
> void
> -xfs_alert_tag(
> +_xfs_alert_tag(
> 	const struct xfs_mount	*mp,
> 	int			panic_tag,
> 	const char		*fmt, ...)
> diff --git a/fs/xfs/xfs_message.h b/fs/xfs/xfs_message.h
> index 2f609800e806..6f9a1b67c4d7 100644
> --- a/fs/xfs/xfs_message.h
> +++ b/fs/xfs/xfs_message.h
> @@ -6,34 +6,45 @@
>
> struct xfs_mount;
>
> +#define xfs_printk_index_wrap(kern_level, mp, fmt, ...)		\
> +({								\
> +	printk_index_subsys_emit("%sXFS%s: ", kern_level, fmt);	\
> +	xfs_printk_level(kern_level, mp, fmt, ##__VA_ARGS__);	\
> +})
> extern __printf(3, 4)
> void xfs_printk_level(
> 	const char *kern_level,
> 	const struct xfs_mount *mp,
> 	const char *fmt, ...);
> #define xfs_emerg(mp, fmt, ...) \
> -	xfs_printk_level(KERN_EMERG, mp, fmt, ##__VA_ARGS__)
> +	xfs_printk_index_wrap(KERN_EMERG, mp, fmt, ##__VA_ARGS__)
> #define xfs_alert(mp, fmt, ...) \
> -	xfs_printk_level(KERN_ALERT, mp, fmt, ##__VA_ARGS__)
> +	xfs_printk_index_wrap(KERN_ALERT, mp, fmt, ##__VA_ARGS__)
> #define xfs_crit(mp, fmt, ...) \
> -	xfs_printk_level(KERN_CRIT, mp, fmt, ##__VA_ARGS__)
> +	xfs_printk_index_wrap(KERN_CRIT, mp, fmt, ##__VA_ARGS__)
> #define xfs_err(mp, fmt, ...) \
> -	xfs_printk_level(KERN_ERR, mp, fmt, ##__VA_ARGS__)
> +	xfs_printk_index_wrap(KERN_ERR, mp, fmt, ##__VA_ARGS__)
> #define xfs_warn(mp, fmt, ...) \
> -	xfs_printk_level(KERN_WARNING, mp, fmt, ##__VA_ARGS__)
> +	xfs_printk_index_wrap(KERN_WARNING, mp, fmt, ##__VA_ARGS__)
> #define xfs_notice(mp, fmt, ...) \
> -	xfs_printk_level(KERN_NOTICE, mp, fmt, ##__VA_ARGS__)
> +	xfs_printk_index_wrap(KERN_NOTICE, mp, fmt, ##__VA_ARGS__)
> #define xfs_info(mp, fmt, ...) \
> -	xfs_printk_level(KERN_INFO, mp, fmt, ##__VA_ARGS__)
> +	xfs_printk_index_wrap(KERN_INFO, mp, fmt, ##__VA_ARGS__)
> #ifdef DEBUG
> #define xfs_debug(mp, fmt, ...) \
> -	xfs_printk_level(KERN_DEBUG, mp, fmt, ##__VA_ARGS__)
> +	xfs_printk_index_wrap(KERN_DEBUG, mp, fmt, ##__VA_ARGS__)
> #else
> #define xfs_debug(mp, fmt, ...) do {} while (0)
> #endif
>
> +#define xfs_alert_tag(mp, tag, fmt, ...)			\
> +({								\
> +	printk_index_subsys_emit("%sXFS%s: ", KERN_ALERT, fmt);	\
> +	_xfs_alert_tag(mp, tag, fmt, ##__VA_ARGS__);		\
> +})
> +
> extern __printf(3, 4)
> -void xfs_alert_tag(const struct xfs_mount *mp, int tag, const char *fmt, ...);
> +void _xfs_alert_tag(const struct xfs_mount *mp, int tag, const char *fmt, ...);
>
>
> #define xfs_printk_ratelimited(func, dev, fmt, ...)			\
> --
> 2.35.1