Subject: Re: watchdog timer
To: Steve Bellovin <smb@research.att.com>
From: Simon Burge <simonb@wasabisystems.com>
List: netbsd-users
Date: 04/07/2003 09:14:18
On Sat, Apr 05, 2003 at 04:12:04PM -0500, Steve Bellovin wrote:

> Is there some built-in software watchdog timer?  wdogctl(8) on 1.6
> implies that there is; running wdogctl says that nothing is configured.
> A quick grep didn't turn anything up, but it's a fairly obvious feature
> to want -- am I missing something?  (Or is that a hint that I should
> write such a driver?)

The wdogctl interface is meant for hardware watchdog timers.  This is
what wdogctl reports on a IBM PowerPC 405GP box:

	walnut# wdogctl
	Available watchdog timers:
		wdog0, 5 second period

Setting the timer and disabling the tickle results in the CPU itself
doing a hardware reset after the specified time.

I'm not sure how you'd define a software watchdog timer (since by
definition if the software is hosed it wont be able to tickle the
software timer(!)), unless you mean you want something for userland
process.

Simon.
--
Simon Burge                                   <simonb@wasabisystems.com>
NetBSD Development, Support and Service:   http://www.wasabisystems.com/