watchdog end-user interface

[Alfred Perlstein]

On 10/19/16 4:09 AM, Andriy Gapon wrote:
> I know that there are people thinking about improving our watchdog
> infrastructure.  Maybe it's time to discuss some ideas in public.
>
> I would like to start with discussing the end-user, or rather administrative,
> interface to the watchdog system.
>
> watchdogd always had -t timeout option.
> Not a too long time ago it has also grown a handful of new options:
> --softtimeout
> --softtimeout-action action
> --pretimeout timeout
> --pretimeout-action action
>
> I want to question if those options really belong to watchdogd.
> When a watchdog timer expires that results in a system-wide action (like a
> system reset).  To me, that implies that there should be a single system-wide
> configuration point.  And I am not sure that the daemon is the best choice for it.
>
> Personally I would prefer a sysctl interface for the following reasons:
> - easier to change the configuration
> - easier to query current values
> - easier to signal that a value getting set may be different from a requested value
>
> In my opinion, watchdogd should only be concerned with running a check action
> and patting the dog(s).  And, by extension, WDIOCPATPAT should not re-configure
> the timeout, it should just reload the timers.
>
Please look at the Linux interface for watchdogs, it is pretty good and 
could/should be ported to us.

-Alfred