[dm-devel] [PATCH v2 8/9] libmultipath: check_rdac(): pre-check in hwtable

[Hannes Reinecke]

On 3/15/19 6:19 PM, Martin Wilck wrote:
> Currently check_rdac() always runs an SG_IO for VPD 0xc9 to check
> if the storage supports RDAC. This is an extra IO, and may cause
> annoying error messages on the storage side for non-RDAC arrays.
> Do the RDAC override only for arrays that have legacy configuration
> to use the rdac checker.
> 
> Cc: Steve.Schremmer at netapp.com
> Cc: NetApp RDAC team <ng-eseries-upstream-maintainers at netapp.com>
> Cc: Hannes Reinecke <hare at suse.com>
> Signed-off-by: Martin Wilck <mwilck at suse.com>
> ---
>   libmultipath/propsel.c | 8 ++++++++
>   1 file changed, 8 insertions(+)
> 
> diff --git a/libmultipath/propsel.c b/libmultipath/propsel.c
> index 27474f05..8c08a5cc 100644
> --- a/libmultipath/propsel.c
> +++ b/libmultipath/propsel.c
> @@ -470,9 +470,17 @@ check_rdac(struct path * pp)
>   {
>   	int len;
>   	char buff[44];
> +	const char *checker_name = NULL;
> +	/* dummy, for do_set_from_hwe */
> +	const char *origin __attribute__((unused));
>   
>   	if (pp->bus != SYSFS_BUS_SCSI)
>   		return 0;
> +	/* Avoid ioctl if this is likely not an RDAC array */
> +	do_set_from_hwe(checker_name, pp, checker_name, NULL);
> +out:    /* for do_set_from_hwe */
> +	if (!checker_name || strcmp(checker_name, RDAC))
> +		return 0;
>   	len = get_vpd_sgio(pp->fd, 0xC9, buff, 44);
>   	if (len <= 0)
>   		return 0;
> 
*origin? dummy for do_set_from_hwe()?
What funky interface is that?

Please redesign do_set_from_hwe() so as _not_ to require 'magic' variables.

Cheers,

Hannes
-- 
Dr. Hannes Reinecke		               zSeries & Storage
hare at suse.com			               +49 911 74053 688
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