Re: [Update][PATCH] MM / PM: Force GFP_NOIO during suspend/hibernation and resume

Rafael J. Wysocki
2010-01-25T21:48:55Z

On Saturday 23 January 2010, Maxim Levitsky wrote:
> On Fri, 2010-01-22 at 22:19 +0100, Rafael J. Wysocki wrote:
> > On Friday 22 January 2010, Maxim Levitsky wrote:
> > > On Fri, 2010-01-22 at 10:42 +0900, KOSAKI Motohiro wrote:
> > > > > > > Probably we have multiple option. but I don't think GFP_NOIO is good
> > > > > > > option. It assume the system have lots non-dirty cache memory and it isn't
> > > > > > > guranteed.
> > > > > >
> > > > > > Basically nothing is guaranteed in this case. However, does it actually make
> > > > > > things _worse_?
> > > > >
> > > > > Hmm..
> > > > > Do you mean we don't need to prevent accidental suspend failure?
> > > > > Perhaps, I did misunderstand your intention. If you think your patch solve
> > > > > this this issue, I still disagree. but If you think your patch mitigate
> > > > > the pain of this issue, I agree it. I don't have any reason to oppose your
> > > > > first patch.
> > > >
> > > > One question. Have anyone tested Rafael's $subject patch?
> > > > Please post test result. if the issue disapper by the patch, we can
> > > > suppose the slowness is caused by i/o layer.
> > >
> > > I did.
> > >
> > > As far as I could see, patch does solve the problem I described.
> > >
> > > Does it affect speed of suspend? I can't say for sure. It seems to be
> > > the same.
> >
> > Thanks for testing.
>
> I'll test that too, soon.
> Just to note that I left my hibernate loop run overnight, and now I am
> posting from my notebook after it did 590 hibernate cycles.

Did you have a chance to test it?

> Offtopic, but Note that to achieve that I had to stop using global acpi
> hardware lock. I tried all kinds of things, but for now it just hands
> from time to time.
> See http://bugzilla.kernel.org/show_bug.cgi?id=14668

I'm going to look at that later this week, although I'm not sure I can do more
than Alex about that.

Rafael