RFC: enhanced watchdog.

[Alfred Perlstein]

On 1/19/13 6:21 AM, Poul-Henning Kamp wrote:
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> In message <50FA3D36.4080709 at mu.org>, Alfred Perlstein writes:
>
>> We at iX are trying to enhance the watchdog and we think some of the
>> changes may benefit the community as a whole.
> The initial watchdog support was generalized from only two examples
> and therefore quite crude.
>
> I think your proposed improvements make good sense.

Thanks for the kind words.
>
> I will generally warn you not to make things too complex though,
> it's important that the watchdog subsystem does not become a
> cause of failure on its own.
Agreed.  I get very nervous when I see rtprio calls in any program and 
will certainly tread very carefully here.

>
> Having a kernel thread which tries to get attention some delta-T
> before the hardware watchdog is supposed to kick in, also sounds
> like a good idea, but its information is going to be quite unreliable.
>
> One wish I have heard, was to be able to use multiple WD's separately,
> the current API sort of treats them as a redundant pool.
Yes, this also is interesting to me.  I started sketching up some ways 
to do this, but then realized I was probably reinventing the wheel.

Can someone refer me to examples of a system I could crib from instead 
of starting from scratch?

-Alfred