|
xen-devel
RE: [Xen-devel] RE: Question about Xen S3 and resume code - Linux dom0 n
Hi, Konrad,
any update on this S3 problem you're seeing?
I just got a chance to give a try on my Dell core-i7 platform with a Ubuntu
10.10
system.
Xen version is:
changeset: 23632:33717472f37e
tag: tip
user: Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx>
date: Tue Jun 28 18:15:44 2011 +0100
summary: libxc: Squash xc_e820.h (and delete) into xenctrl.h
for dom0 I use origin/master plus ACPI patches queued on your
origin/devel/acpi-s3.v0:
commit 4aa69dc48e031276b4d771dcb227d553fd3def0b
Merge: df5b2b6 9f90a3b
Author: Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx>
Date: Tue Jun 21 09:34:31 2011 -0400
Merge branch '3.0-rc1-rem_pg_reserve-4' of
git://xenbits.xen.org/people/sstabellini/linux-pvhvm
w/ or w/o ACPI processor patches on my box ACPI S3 just works well.
Thanks
Kevin
> From: Tian, Kevin
> Sent: Tuesday, June 21, 2011 7:22 AM
>
> > From: Konrad Rzeszutek Wilk [mailto:konrad.wilk@xxxxxxxxxx]
> > Sent: Monday, June 20, 2011 8:36 PM
> >
> > > ideally ACPI S3/S5 has nothing to do with ACPI processor driver which is
> > > for
> > Cx/Px.
> >
> > Right..
> > >
> > > >
> > > > (which is in the devel/acpi-s3.v0 branch).
> > > >
> > > > the hypervisor, after an S3 resume sits forever in the default_idle. The
> > > > Linux dom0 is stuck looping (I think) around SCHEDOP_block hypercall.
> > > >
> > > > http://darnok.org/xen/devel.acpi-s3.v1.serial.log
> > > >
> > > > If that patch above is present and I've cpufreq=xen on the Xen
> > > > hypervisor then Linux kernel gets unstuck and returns to userspace:
> > > >
> > > > http://darnok.org/xen/devel.acpi-s3.v0.serial.log
> > >
> > > Compare your logs, the major difference is:
> > >
> > > [ 168.754739] calling i2c-8+ @ 3096
> > > [ 168.758200] call i2c-8+ returned 0 after 0 usecs
> > > <<< 1st case stuck here
> > > [ 168.762882] calling card0-VGA-1+ @ 3096
> > > [ 168.766867] call card0-VGA-1+ returned 0 after 0 usecs
> > > [ 168.772085] calling ttm+ @ 3096
> > > [ 168.775360] call ttm+ returned 0 after 0 usecs
> > > [ 168.779870] PM: resume of devices complete after 13117.603 msecs
> > > [ 168.786006] PM: Finishing wakeup.
> > > <<<2nd case forward progress
> > >
> > > It looks that VGA card resume has some problem on resume, which then
> >
> > In both cases - with the patch and without..
>
> that's expected since device suspend is always invoked in the S3 path.
>
> >
> > > makes dom0 stay in idle loop and thus block hypercall, and then due to
> > > no runnable vcpu so Xen most time in idle_loop too. In earlier log
> > > there're
> > > some stack trace in i915 driver. Perhaps you can try a different machine
> >
> > Or remove the i915 just to eliminate that.
>
> So any result there? :-)
>
> > > or try native S3 on same box to make sure it's not mixed with native
> > > issues.
> > >
> > > >
> > > > (however, if I set cpuidle=0 cpufreq=none on the hypervisor line and
> > > > have the 9f301b0a0081676dfc71b7f0898295e6bcba391a patch it still
> > > > gets stuck).
> > > >
> > > > I figured that the primary reason the guest is allowed to
> > > > exit is SCHEDOP_block loop is b/c the pm_idle call is set to the
> > > > acp_processor_idle which does "something" extra after the machine
> comes
> > > > out of a S3 suspend.
> > >
> > > If that's the case I think you should disable CONFIG_ACPI_PROCESSOR in
> > dom0
> > > before incorporating Xen specific version (the patch you tried). We don't
> want
> > > dom0 to play with Cx directly b/c it's the responsibility of Xen.
> >
> > Huh? You misunderstood me. The 'acpi_processor_idle' is the hypervisor's
> > idle loop. It can be running inside of that one, or the 'default_idle'
> > loop. Hence
>
> running inside which one? I'd think only default_idle invokes it when current
> cpu
> is actually idle.
>
> > my question why would that specific hypervisor idle loop make dom0 run
> nicely
> > while the default one would not.
>
> this is counterintuitive to me honestly speaking. I'd more think that
> acpi_processor_idle may cause some issue than pure "sti;hlt" because acpi
> version has more logic to handle. In earlier day when it's still in
> stabilization
> phase, we did observe some non-exit case from deep Cstate but this never
> happens on pure hlt.
>
> IOW, I don't take this idle path as a necessary step to make S3 resume
> working,
> which is simply related when the cpu has nothing to do...
>
> >
> > In dom0, irregardless of the patches, the 'default_idle' is run which makes
> > the
> > xen_safe_halt paravirt call.
>
> OK, that matches my expectation then.
>
> >
> > >
> > > Of course we still need figure out why same issues occur with cpuidle=0/
> > > cpufreq=none, which however can be revisited after the basic S3 works. :-)
> >
> > Right. The end result of those parameters is that the 'default_idle' in the
> > hypervisor is choosen instead of the 'acpi_processor_idle' one.
> > >
> > > >
> > > > Any ideas?
> > >
> > > No other ideas for now. From historical view Xen S3 was supported before
> >
> > Hmm, I am actually tempted to start commenting out code in the
> > acpi_processor_idle
> > and seeing what will cause it to have the same failure as 'default_idle'.
>
> you can also try "max_cstates=1" to see any difference, which is expected to
> has similar effect as safe_halt().
>
> Thanks
> Kevin
>
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@xxxxxxxxxxxxxxxxxxx
> http://lists.xensource.com/xen-devel
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel
|
|
|
Home