Re: [PATCH v4] pm_ops: add system quiesce/activate hooks

[Benjamin Herrenschmidt <benh@kernel.crashing.org>]

On Mon, 2007-04-16 at 09:32 +0200, Pavel Machek wrote:

> Does the "weird motherboard" stuff need to be suspended/resumed for
> swsusp memory snapshot?

I don't think so... I need to get into the details to verify, it might
make sense to run some of the "resume" bits of it when resuming a STD
kernel but I doubt it. It won't harm tho.

> Well, I guess arch_pm_irq_quiesce_for_s2ram() would be
> acceptable... but that would be only called for s2ram... which should
> be enough for decrementer AFAICT.

That's a pretty ugly name :-0 I'd be fine just having
arch_pm_irq_quiesce() and only call it from the right s2ram call sites,
or pass it an argument indicating the type of suspend and let the arch
decide what to do. I fail to see the point in being so overly
restrictive on something which will in the long run have little to no
impact.

> As decrementer is special for s2ram, we can add the hook. (It is
> single hook). If we need to do something for snapshots, too... well,
> we can still add arch_pm_irq_quiesce_for_snapshot() and
> arch_pm_irq_quiesce_for_powerdown() etc, but it would get ugly fast.

Which is why I think we should stick with the pair

arch_pm_irq_quiesce() and arch_pm_irq_activate() or whatever name you
come up with, and either have them only called for s2ram or pass the
suspend type to them, I don't like the over long weird names you are
coming up with but that's a detail :-)

Ben.