[Devel] [PATCH RH9] ploop: simplify ploop_status

[Kirill Tkhai]

On 21.10.2021 21:32, Cyrill Gorcunov wrote:
> From: Cyrill Gorcunov <gorcunov at gmail.com>
> 
> We can get rid of sprintf usage when encoding the status.
> Just fill the string directly.
> 
> Cc: Kirill Tkhai <ktkhai at virtuozzo.com>
> Signed-off-by: Cyrill Gorcunov <gorcunov at gmail.com>

Acked-by: Kirill TKhai <ktkhai at virtuozzo.com>

> ---
>  drivers/md/dm-ploop-target.c |   13 +++++++------
>  1 file changed, 7 insertions(+), 6 deletions(-)
> 
> --- vzkernel.orig/drivers/md/dm-ploop-target.c
> +++ vzkernel/drivers/md/dm-ploop-target.c
> @@ -435,20 +435,21 @@ static void ploop_status(struct dm_targe
>  			 unsigned int maxlen)
>  {
>  	struct ploop *ploop = ti->private;
> -	char stat[16] = { 0 }, *p = stat;
> +	char stat[16], *p = stat;
>  	ssize_t sz = 0;
>  
>  	down_read(&ploop->ctl_rwsem);
>  	if (ploop->falloc_new_clu)
> -		p += sprintf(p, "f");
> +		*p++ = 'f';
>  	if (ploop->tracking_bitmap)
> -		p += sprintf(p, "t");
> +		*p++ = 't';
>  	if (READ_ONCE(ploop->noresume))
> -		p += sprintf(p, "n");
> +		*p++ = 'n';
>  	if (READ_ONCE(ploop->event_enospc))
> -		p += sprintf(p, "s");
> +		*p++ = 's';
>  	if (p == stat)
> -		p += sprintf(p, "o");
> +		*p++ = 'o';
> +	*p++ = '\0';
>  	up_read(&ploop->ctl_rwsem);
>  
>  	BUG_ON(p - stat >= sizeof(stat));
>