[dm-devel] [PATCH 64/74] multipathd: check_path(): set retrigger_delay if necessary

[Benjamin Marzinski]

On Thu, Jul 09, 2020 at 12:51:35PM +0200, mwilck at suse.com wrote:
> From: Martin Wilck <mwilck at suse.com>
> 
> In a follow up patch, we will set INIT_MISSING_UDEV and set tick=1
> (minimal) at the same time. In this case, which is new, check_path()
> must reset the delay when it first triggers an uevent.

Maybe I'm just being obtuse here, but I don't get what this does.
pp->tick will always be 0 for any path that makes it to the check

if (!pp->mpp && pp->initialized == INIT_MISSING_UDEV) {

And then if it's not out of retries, the path will get set to
INIT_REQUESTED_UDEV, and pathinfo() will take care of resetting pp->tick
when it gets called by the new uevent.

If it is out of retries, the path won't get pp->tick reset, which seems
wrong, but it that case it should probably be set to max_checkint, like
happens when the "add missing paths" code fails.

Or like I said, maybe I'm just missing something.
-Ben

> 
> Signed-off-by: Martin Wilck <mwilck at suse.com>
> ---
>  multipathd/main.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/multipathd/main.c b/multipathd/main.c
> index 7b2d320..0cd0ee6 100644
> --- a/multipathd/main.c
> +++ b/multipathd/main.c
> @@ -2019,6 +2019,7 @@ check_path (struct vectors * vecs, struct path * pp, unsigned int ticks)
>  	int disable_reinstate = 0;
>  	int oldchkrstate = pp->chkrstate;
>  	int retrigger_tries, verbosity;
> +	unsigned int retrigger_delay;
>  	unsigned int checkint, max_checkint;
>  	struct config *conf;
>  	int marginal_pathgroups, marginal_changed = 0;
> @@ -2036,6 +2037,7 @@ check_path (struct vectors * vecs, struct path * pp, unsigned int ticks)
>  
>  	conf = get_multipath_config();
>  	retrigger_tries = conf->retrigger_tries;
> +	retrigger_delay = conf->retrigger_delay;
>  	checkint = conf->checkint;
>  	max_checkint = conf->max_checkint;
>  	verbosity = conf->verbosity;
> @@ -2048,6 +2050,8 @@ check_path (struct vectors * vecs, struct path * pp, unsigned int ticks)
>  	};
>  
>  	if (!pp->mpp && pp->initialized == INIT_MISSING_UDEV) {
> +		if (pp->tick != retrigger_delay)
> +			pp->tick = conf->retrigger_delay;
>  		if (pp->retriggers < retrigger_tries) {
>  			condlog(2, "%s: triggering change event to reinitialize",
>  				pp->dev);
> -- 
> 2.26.2