Re: [PATCH 3/3] xfs: shorten the shutdown messages to a single line

[Christoph Hellwig <hch@infradead.org>]

On Fri, Jun 18, 2021 at 11:54:10AM -0700, Darrick J. Wong wrote:
> From: Darrick J. Wong <djwong@kernel.org>
> 
> Consolidate the shutdown messages to a single line containing the
> reason, the passed-in flags, the source of the shutdown, and the end
> result.  This means we now only have one line to look for when
> debugging, which is useful when the fs goes down while something else is
> flooding dmesg.
> 
> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
> ---
>  fs/xfs/xfs_fsops.c |   16 ++++++++--------
>  1 file changed, 8 insertions(+), 8 deletions(-)
> 
> 
> diff --git a/fs/xfs/xfs_fsops.c b/fs/xfs/xfs_fsops.c
> index b7f979eca1e2..6ed29b158312 100644
> --- a/fs/xfs/xfs_fsops.c
> +++ b/fs/xfs/xfs_fsops.c
> @@ -538,25 +538,25 @@ xfs_do_force_shutdown(
>  
>  	if (flags & SHUTDOWN_FORCE_UMOUNT) {
>  		xfs_alert(mp,
> -"User initiated shutdown received. Shutting down filesystem");
> +"User initiated shutdown (0x%x) received. Shutting down filesystem",
> +				flags);
>  		return;
>  	}

So SHUTDOWN_FORCE_UMOUNT can actually be used together with
SHUTDOWN_LOG_IO_ERROR so printing something more specific could be
useful, although I'd prefer text over the hex flags.

>  	if (flags & SHUTDOWN_CORRUPT_INCORE) {
>  		xfs_alert_tag(mp, XFS_PTAG_SHUTDOWN_CORRUPT,
> -"Corruption of in-memory data detected.  Shutting down filesystem");
> +"Corruption of in-memory data (0x%x) detected at %pS (%s:%d).  Shutting down filesystem",
> +				flags, __return_address, fname, lnnum);
>  		if (XFS_ERRLEVEL_HIGH <= xfs_error_level)
>  			xfs_stack_trace();
>  	} else if (logerror) {
>  		xfs_alert_tag(mp, XFS_PTAG_SHUTDOWN_LOGERROR,
> -			"Log I/O Error Detected. Shutting down filesystem");
> +"Log I/O error (0x%x) detected at %pS (%s:%d). Shutting down filesystem",
> +				flags, __return_address, fname, lnnum);
>  	} else {
>  		xfs_alert_tag(mp, XFS_PTAG_SHUTDOWN_IOERROR,
> -			"I/O Error Detected. Shutting down filesystem");
> +"I/O error (0x%x) detected at %pS (%s:%d). Shutting down filesystem",
> +				flags, __return_address, fname, lnnum);
>  	}

However once we get here, flags can have exactly one specific value,
so printing it (especially as unreadable hex value) is completely
pointless.