Re: [PATCH] create CONFIG_SUSPEND_UP_POSSIBLE

From: Pavel Machek
Date: Sun Aug 05 2007 - 14:36:53 EST


On Fri 2007-08-03 15:23:19, Len Brown wrote:
> On Tuesday 31 July 2007 02:38, Pavel Machek wrote:
> > Hi!
> >
> > > Without this change, it is possible to build CONFIG_HIBERNATE
> > > on all !SMP architectures, but not necessarily their SMP versions.
> >
> > Did you want to say "CONFIG_SUSPEND"?
>
> Yes.
>
> > > I don't know for sure if the architecture list under SUSPEND_UP_POSSIBLE
> > > is correct. For now it simply matches the list for
> > > SUSPEND_SMP_POSSIBLE.
> >
> > I do not think it is.
> >
> > > Signed-off-by: Len Brown <len.brown@xxxxxxxxx>
> > > ---
> > > Kconfig | 7 ++++++-
> > > 1 file changed, 6 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/kernel/power/Kconfig b/kernel/power/Kconfig
> > > index 412859f..ccf6576 100644
> > > --- a/kernel/power/Kconfig
> > > +++ b/kernel/power/Kconfig
> > > @@ -72,6 +72,11 @@ config PM_TRACE
> > > CAUTION: this option will cause your machine's real-time clock to be
> > > set to an invalid time after a resume.
> > >
> > > +config SUSPEND_UP_POSSIBLE
> > > + bool
> > > + depends on (X86 && !X86_VOYAGER) || (PPC64 && (PPC_PSERIES ||
> >
> > At least ARM can do suspend, too... probably others. I was under
> > impression that SUSPEND is "supported" by all the architectures, just
> > some of them veto it at runtime (using pm_ops or how was it renamed).
>
> The reason this entire thread started is because Linus, Jeff and others
> said that they didn't want code magically compiled into their kernel
> that they did not explicitly ask for -- even if the savings were small
> and that kernel was already something rather beefy, such as ACPI+SMP.
>
> The current code is simply broken, because it allows SUSPEND
> on IA64 if UP, but not on SMP. It should really be neither.

Actually, it should be both, AFAICT. Suspend infrastructure should be
there, just returing -EINVAL... that's how it worked in 2.6.22 IIRC.

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/