Re: s2ram slow (radeon) / failing (usb)

["Bruno Prémont" <bonbons@linux-vserver.org>]

On Sun, 02 May 2010 Alan Stern <stern@rowland.harvard.edu> wrote:
> On Sun, 2 May 2010, Bruno [UTF-8] Prémont wrote:
> > On a IEI Kino 690S1 I'm having a hard time to get s2ram running.
> > It freezes during device suspend (unless I rmmod everything USB
> > related) - usb fails even in pm_test case 'devices'.
> > 
> > When the system is able to suspend it takes an eternity (more than 3
> > minutes to wake-up, the radeon apparently being responsible for quite
> > a big share of that slowness.
> > 
> > 
> > During resume early it looks like every PCI access needs about a second,
> > and there are a few cases where during lots of seconds nothing seems to
> > happen and the first event following is related to radeon.
> > 
> > The kernel used is todays Linus's tree at commit be1066bbcd443a65df312fdecea7e4959adedb45
> > with Dave's drm-linus and drm-radeon-testing applied on top.
> > 
> > Note, I've not been able to suspend to RAM properly recently (last one
> > that worked correctly but resumed without graphics was some-when during
> > 2.6.2x, before KMS)
> > Since then the system would either fail suspend or resume.
> > 
> > Manual changes I applied in order to find out some context information:
> > - add a few debugging printk's to ata/ahci as that was the last entry
> >   on serial console for freezing suspends (that one succeeded but
> >   following step never completed, from suspend_prepare that would have
> >   been USB => unload usb before suspend)
> > - strip "if EMBEDED" from CONFIG_SERIAL_8250_PNP and disabled it so serial
> >   console would continue working as long as possible and output suspend
> >   progress (resume output happens only very late)
> > 
> > Is there some additional information I could gather in order do help
> > improving s2ram on this system?
> > - get it to suspend with usb loaded (ohci + ehci)
> > - get it to resume a reasonable speed
> 
> There's no way to fix the USB problem without knowing what goes wrong.  
> Let's see how far you get before the system freezes on a kernel with 
> CONFIG_USB_DEBUG enabled.

Am I missing something?

I've enabled CONFIG_USB_DEBUG but don't see any additional module parameter
nor anything extra to toggle and I don't get more output than without it.

Device suspend (pm_test = device) works well when there is no USB device
connected, but with USB keyboard I get the freeze (though the keyboard
is still usable, e.g. CAPS key works and I can issue SYSRQ commands).

When I issue sysreq-t, I find the following suspicious entry:
[  669.112505] usbhid_resume D ffff88007a085fd8     0  1145      2 0x00000000
[  669.112505]  ffff88007a085e20 0000000000000046 ffff88007a085fd8 ffff88007c536820
[  669.112505]  ffff88007a085fd8 ffff88007a085fd8 00000000000129c0 00000000000129c0
[  669.112505]  ffff88007c536820 ffff88007cf3f040 ffff88007a085fd8 ffff88007a085fd8
[  669.112505] Call Trace:
[  669.112505]  [<ffffffff8105d765>] refrigerator+0x95/0xf0
[  669.112505]  [<ffffffff81051a16>] worker_thread+0xc6/0x1e0
[  669.112505]  [<ffffffff81055e90>] ? autoremove_wake_function+0x0/0x40
[  669.112505]  [<ffffffff81051950>] ? worker_thread+0x0/0x1e0
[  669.112505]  [<ffffffff810559be>] kthread+0x8e/0xa0
[  669.112505]  [<ffffffff81003a94>] kernel_thread_helper+0x4/0x10
[  669.112505]  [<ffffffff81055930>] ? kthread+0x0/0xa0
[  669.112505]  [<ffffffff81003a90>] ? kernel_thread_helper+0x0/0x10

Except for that one there are a few async/* tasks waiting.

Thanks,
Bruno