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

Pavel Machek
2010-08-14T07:38:44Z

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
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