Re: Attempted summary of suspend-blockers LKML thread, take three

From: Pavel Machek
Date: Sat Aug 14 2010 - 03:39:06 EST


Hi!

> > > > Think in terms of an ARM laptop. What good is opportunistic suspend if
> > > > it's not going to help when the laptop is being used?
> > >
> > > For when the laptop is not being used, presumably.
> >
> > Or in time between keystrokes for most of the platform (backlight
> > excepted). The Intel MID x86 devices are at the point that suspend/resume
> > time on x86 is being hurt by the kernel rewriting smp alternatives as we
> > go from 2 processors live to 1 and back.
>
> Given that you are talking about going from 2 processors to 1 and back,
> I would guess that you are not actually talking about suspend/resume,
> which is a system-wide thing rather than a CPU-by-CPU thing. I am not
> sure whether you are using CPU hotplug or invoking SMP alternatives once
> all but one CPU is idle.

When entering system suspend, we disable non-boot-CPUs to simplify
locking. We reenable them when going out of suspend.
Pavel
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/