Re: [PATCH] watchdog: nohz: don't run watchdog on nohz_full cores

Christoph Lameter
2015-03-31T10:17:23Z

On Mon, 30 Mar 2015, cmetcalf@ezchip.com wrote:

> Running watchdog can be a helpful debugging feature on regular
> cores, but it's incompatible with nohz_full, since it forces
> regular scheduling events. Accordingly, just exit out immediately
> from any nohz_full core.

At this point we still have a timer tick every second. So just change the
way the checking occurs that it can be done during the once per second
tick for now? If the tick idle period is expanded later maybe only run the
watchdog activity during those inevitable ticks?

It may be best if the watchdog could be configured as to which processors
it should run on?