Re: gen6 (SNB) GPU still stalling besides latest patches

Re: gen6 (SNB) GPU still stalling besides latest patches

[Nicolas Kalkhof]

Hi Jesse,

I've tried your patch below. It locked up my machine a few seconds after X startup :(.
I didn't use any boot parameter. I've changed the parameters during runtime by echoing sysfs.

I've filed a bug under https://bugs.freedesktop.org/show_bug.cgi?id=38529[../../jump.htm?goto=https%3A%2F%2Fbugs.freedesktop.org%2Fshow_bug.cgi%3Fid%3D38529][../../jump.htm?goto=https%3A%2F%2Fbugs.freedesktop.org%2Fshow_bug.cgi%3Fid%3D38529]. Chris Wilson already proposed a patch that solves the stalling and so far my system runs stable even with SNA enabled in xf86-video-intel.

However now it seems I'm unable to get my framebuffer console back after I bailed out of X. The screen stays black but my system is still responsive via ssh. This happens without your patch. I'll do some more investigation to make sure I didnt introduce this issue.

Thanks and regards,
nic


-----Ursprüngliche Nachricht-----
Von: "Jesse Barnes" <jbarnes@virtuousgeek.org>
Gesendet: Jun 21, 2011 6:55:27 PM
An: "Nicolas Kalkhof" <nkalkhof@web.de>
Betreff: Re: [Intel-gfx] gen6 (SNB) GPU still stalling besides latest patches

>On Tue, 21 Jun 2011 18:12:56 +0200 (CEST)
>"Nicolas Kalkhof" <nkalkhof@web.de> wrote:
>
>> Hi Jesse,
>>
>> thanks for the infiormation. I've switched rc6 off by
>> echo 0 > /sys/module/i915/parameters/i915_enable_rc6
>> this should do it, right?
>> cat /sys/module/i915/parameters/i915_enable_rc6 yields "0"
>>
>> Are you referring to this patch? https://lkml.org/lkml/2011/6/17/371
>> It should be included in kernel 3.0-rc4 and didn't help here :(
>
>So there are actually a few things that could go wrong in this area.
>The problem may be RC6 related, but it could also be turbo related (our
>GPU frequency adjustment code). Can you boot without the module
>parameter and try this patch and see what happens (after a cold boot)?
>
>Thanks,
>Jesse
>
>diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_d
>index 81a9059..3c589cb 100644
>--- a/drivers/gpu/drm/i915/intel_display.c
>+++ b/drivers/gpu/drm/i915/intel_display.c
>@@ -7788,9 +7788,6 @@ void intel_modeset_init(struct drm_device *dev)
> intel_init_emon(dev);
> }
>
>- if (IS_GEN6(dev))
>- gen6_enable_rps(dev_priv);
>-
> INIT_WORK(&dev_priv->idle_work, intel_idle_update);
> setup_timer(&dev_priv->idle_timer, intel_gpu_idle_timer,
> (unsigned long)dev);
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Re: gen6 (SNB) GPU still stalling besides latest patches

[Chris Wilson]

On Tue, 21 Jun 2011 19:41:52 +0200 (CEST), "Nicolas Kalkhof" <nkalkhof@web.de> wrote:
> However now it seems I'm unable to get my framebuffer console back after I bailed out of X. The screen stays black but my system is still responsive via ssh. This happens without your patch. I'll do some more investigation to make sure I didnt introduce this issue.

No, that's another bug with /dev/dri/card0 not honouring O_NONBLOCK. Give
X a swift kick and it'll wake up again.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre

Re: gen6 (SNB) GPU still stalling besides latest patches

[Andrew Lutomirski]

On Tue, Jun 21, 2011 at 2:18 PM, Chris Wilson <chris@chris-wilson.co.uk> wrote:
> On Tue, 21 Jun 2011 19:41:52 +0200 (CEST), "Nicolas Kalkhof" <nkalkhof@web.de> wrote:
>> However now it seems I'm unable to get my framebuffer console back after I bailed out of X. The screen stays black but my system is still responsive via ssh. This happens without your patch. I'll do some more investigation to make sure I didnt introduce this issue.
>
> No, that's another bug with /dev/dri/card0 not honouring O_NONBLOCK. Give
> X a swift kick and it'll wake up again.
> -Chris

Any plans on fixing this (and related bugs)?  The SNA driver makes X
freeze sometimes for me, and it's hard to recover on a laptop when
ctrl-alt-backspace and even alt-sysrq-v don't seem to give me control
of my system back.

ssh-ing in and killall -9 Xorg works, but it's not so easy on a laptop.

--Andy

Re: gen6 (SNB) GPU still stalling besides latest patches

[Nicolas Kalkhof]

Thanks for bringing that up. Is there a bug report for this issue? I was just about to file a report myself but I don't want to create any duplicates.

@Chris: What do you mean with giving X a kick? Neither mouse nor keyboard are responding anymore. Killing X from a remote ssh is the only option. :(

Btw. This only happens with SNA enabled. When using the classic (UXA?), dropping back to framebuffer console works fine.
I too have a laptop (T420). Is this issues restricted to mobile systems only?

Thanks and regards,
nic


-----Ursprüngliche Nachricht-----
Von: "Andrew Lutomirski" <luto@mit.edu>
Gesendet: Jun 21, 2011 8:24:21 PM
An: "Chris Wilson" <chris@chris-wilson.co.uk>
Betreff: Re: [Intel-gfx] gen6 (SNB) GPU still stalling besides latest patches

>On Tue, Jun 21, 2011 at 2:18 PM, Chris Wilson <chris@chris-wilson.co.uk> wrote:
>> On Tue, 21 Jun 2011 19:41:52 +0200 (CEST), "Nicolas Kalkhof" <nkalkhof@web.de> wrote:
>>> However now it seems I'm unable to get my framebuffer console back after I bailed out of X. The screen stays black but my system is still responsive via ssh. This happens without your patch. I'll do some more investigation to make sure I didnt introduce this issue.
>>
>> No, that's another bug with /dev/dri/card0 not honouring O_NONBLOCK. Give
>> X a swift kick and it'll wake up again.
>> -Chris
>
>Any plans on fixing this (and related bugs)? The SNA driver makes X
>freeze sometimes for me, and it's hard to recover on a laptop when
>ctrl-alt-backspace and even alt-sysrq-v don't seem to give me control
>of my system back.
>
>ssh-ing in and killall -9 Xorg works, but it's not so easy on a laptop.
>
>--Andy
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Re: gen6 (SNB) GPU still stalling besides latest patches

[Chris Wilson]

On Tue, 21 Jun 2011 20:38:51 +0200 (CEST), "Nicolas Kalkhof" <nkalkhof@web.de> wrote:
> Thanks for bringing that up. Is there a bug report for this issue? I was just about to file a report myself but I don't want to create any duplicates.
> 
> @Chris: What do you mean with giving X a kick? Neither mouse nor keyboard are responding anymore. Killing X from a remote ssh is the only option. :(

ssh from-other-machine killall -INT X; is the only way to do it because X
is blocked waiting for an event /dev/dri/card0.
 
> Btw. This only happens with SNA enabled. When using the classic (UXA?), dropping back to framebuffer console works fine.
It's a consequence of handling zaphod and trying to drain all in-fligh DRI2
events to paper-over a crash should one arrive after the Xserver has freed
all Resources without calling the destroy handlers...

> I too have a laptop (T420). Is this issues restricted to mobile systems only?
Any non-blocking read on /dev/dri/card0 will block without patches...
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre

Re: gen6 (SNB) GPU still stalling besides latest patches

[Andrew Lutomirski]

On Tue, Jun 21, 2011 at 3:11 PM, Chris Wilson <chris@chris-wilson.co.uk> wrote:
> On Tue, 21 Jun 2011 20:38:51 +0200 (CEST), "Nicolas Kalkhof" <nkalkhof@web.de> wrote:
>> Thanks for bringing that up. Is there a bug report for this issue? I was just about to file a report myself but I don't want to create any duplicates.
>>
>> @Chris: What do you mean with giving X a kick? Neither mouse nor keyboard are responding anymore. Killing X from a remote ssh is the only option. :(
>
> ssh from-other-machine killall -INT X; is the only way to do it because X
> is blocked waiting for an event /dev/dri/card0.
>
>> Btw. This only happens with SNA enabled. When using the classic (UXA?), dropping back to framebuffer console works fine.
> It's a consequence of handling zaphod and trying to drain all in-fligh DRI2
> events to paper-over a crash should one arrive after the Xserver has freed
> all Resources without calling the destroy handlers...

Shouldn't sysrq-v switch even if X isn't cooperating, though?

--Andy

Re: gen6 (SNB) GPU still stalling besides latest patches

[Chris Wilson]

On Tue, 21 Jun 2011 15:16:27 -0400, Andrew Lutomirski <luto@mit.edu> wrote:
> Shouldn't sysrq-v switch even if X isn't cooperating, though?

That's what the theory says. In practice I find I ssh hostname echo >
/proc/sysrq-trigger... ;-)

If the GPU hung and took the machine with it, only the power switch will
reset it.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre

Re: gen6 (SNB) GPU still stalling besides latest patches

[Nicolas Kalkhof]

Hi Jesse,

thanks for the infiormation. I've switched rc6 off by
echo 0 > /sys/module/i915/parameters/i915_enable_rc6
this should do it, right?
cat /sys/module/i915/parameters/i915_enable_rc6 yields "0"

Are you referring to this patch? https://lkml.org/lkml/2011/6/17/371
It should be included in kernel 3.0-rc4 and didn't help here :(

regards
nico



-----Ursprüngliche Nachricht-----
Von: "Jesse Barnes" <jbarnes@virtuousgeek.org>
Gesendet: Jun 21, 2011 6:06:17 PM
An: "Nicolas Kalkhof" <nkalkhof@web.de>, intel-gfx@lists.freedesktop.org
Betreff: Re: [Intel-gfx] gen6 (SNB) GPU still stalling besides latest patches

>It's i915.i915_enable_rc6=0 for extra added redundancy. You might also
>try Daniel Blueman's IRQ fix.
>
>Jesse
>
>On Tue, 21 Jun 2011 07:57:13 +0200 (CEST)
>"Nicolas Kalkhof" <nkalkhof@web.de> wrote:
>
>> Hi Folks, ok, I'll give it a try this evening. Just one more thing: Should I pass enable_rc6 as a boot parameter like this: "i915.enable_rc6=0" or is it set by echoing sysfs (/sys/module/i915/parameters/...)? regards, nico
>>
>>
>> -----Ursprüngliche Nachricht-----
>> Von: "Jesse Barnes" <jbarnes@virtuousgeek.org>
>> Gesendet: Jun 21, 2011 2:19:29 AM
>> An: "Ted Phelps" <phelps@gnusto.com>
>> Betreff: Re: [Intel-gfx] gen6 (SNB) GPU still stalling besides latest patches
>>
>> >On Tue, 21 Jun 2011 10:01:35 +1000
>> >Ted Phelps <phelps@gnusto.com> wrote:
>> >
>> >>
>> >> Hi Nicolas,
>> >>
>> >> Nicolas Kalkhof writes:
>> >> > SNB GPU still hangs frequently with kernel patches next-20110620
>> >> > raising "drm:i915_hangcheck_ring_idle *ERROR* Hangcheck timer
>> >> > elapsed... gen6 bsd ring idle". This happens when multiple
>> >> > applications (mplayer decoding vaapi stream and some openGL game)
>> >> > running at the same time. With either one running there is no
>> >> > stalling. Could someone please confirm the issue?
>> >> >
>> >> > /sys/module/i915/parameters/semaphores is set to 0
>> >> > xf86-video-intel compiled with --enable-sna
>> >>
>> >> I haven't tried SNA, but I've seen GPU hangs as well (SNB 2600K). I've
>> >> found that disabling RC6 (enable_rc6=0) seems to help. Can you see if
>> >> that helps?
>> >>
>> >> [Note to self: submit a bug report]
>> >
>> >Please do; and please try to confirm that your GPU hangs are really rc6
>> >related. RC6 provides a huge (multiple Watt) power savings, and we
>> >really want it to be robust.
>> >
>> >--
>> >Jesse Barnes, Intel Open Source Technology Center
>>
>>
>> ___________________________________________________________
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>> Toolbar eingebaut! http://produkte.web.de/go/toolbar
>>
>
>
>--
>Jesse Barnes, Intel Open Source Technology Center
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Re: gen6 (SNB) GPU still stalling besides latest patches

[Jesse Barnes]

On Tue, 21 Jun 2011 18:12:56 +0200 (CEST)
"Nicolas Kalkhof" <nkalkhof@web.de> wrote:

> Hi Jesse,
> 
> thanks for the infiormation. I've switched rc6 off by
> echo 0 > /sys/module/i915/parameters/i915_enable_rc6
> this should do it, right?
> cat /sys/module/i915/parameters/i915_enable_rc6 yields "0"
> 
> Are you referring to this patch? https://lkml.org/lkml/2011/6/17/371
> It should be included in kernel 3.0-rc4 and didn't help here :(

So there are actually a few things that could go wrong in this area.
The problem may be RC6 related, but it could also be turbo related (our
GPU frequency adjustment code).  Can you boot without the module
parameter and try this patch and see what happens (after a cold boot)?

Thanks,
Jesse

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_d
index 81a9059..3c589cb 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -7788,9 +7788,6 @@ void intel_modeset_init(struct drm_device *dev)
                intel_init_emon(dev);
        }
 
-       if (IS_GEN6(dev))
-               gen6_enable_rps(dev_priv);
-
        INIT_WORK(&dev_priv->idle_work, intel_idle_update);
        setup_timer(&dev_priv->idle_timer, intel_gpu_idle_timer,
                    (unsigned long)dev);

Re: gen6 (SNB) GPU still stalling besides latest patches

[Jesse Barnes]

It's i915.i915_enable_rc6=0 for extra added redundancy.  You might also
try Daniel Blueman's IRQ fix.

Jesse

On Tue, 21 Jun 2011 07:57:13 +0200 (CEST)
"Nicolas Kalkhof" <nkalkhof@web.de> wrote:

> Hi Folks, ok, I'll give it a try this evening. Just one more thing: Should I pass enable_rc6 as a boot parameter like this: "i915.enable_rc6=0" or is it set by echoing sysfs (/sys/module/i915/parameters/...)? regards, nico
> 
> 
> -----Ursprüngliche Nachricht-----
> Von: "Jesse Barnes" <jbarnes@virtuousgeek.org>
> Gesendet: Jun 21, 2011 2:19:29 AM
> An: "Ted Phelps" <phelps@gnusto.com>
> Betreff: Re: [Intel-gfx] gen6 (SNB) GPU still stalling besides latest patches
> 
> >On Tue, 21 Jun 2011 10:01:35 +1000
> >Ted Phelps <phelps@gnusto.com> wrote:
> >
> >>
> >> Hi Nicolas,
> >>
> >> Nicolas Kalkhof writes:
> >> > SNB GPU still hangs frequently with kernel patches next-20110620
> >> > raising "drm:i915_hangcheck_ring_idle *ERROR* Hangcheck timer
> >> > elapsed... gen6 bsd ring idle". This happens when multiple
> >> > applications (mplayer decoding vaapi stream and some openGL game)
> >> > running at the same time. With either one running there is no
> >> > stalling. Could someone please confirm the issue?
> >> >
> >> > /sys/module/i915/parameters/semaphores is set to 0
> >> > xf86-video-intel compiled with --enable-sna
> >>
> >> I haven't tried SNA, but I've seen GPU hangs as well (SNB 2600K). I've
> >> found that disabling RC6 (enable_rc6=0) seems to help. Can you see if
> >> that helps?
> >>
> >> [Note to self: submit a bug report]
> >
> >Please do; and please try to confirm that your GPU hangs are really rc6
> >related. RC6 provides a huge (multiple Watt) power savings, and we
> >really want it to be robust.
> >
> >--
> >Jesse Barnes, Intel Open Source Technology Center
> 
> 
> ___________________________________________________________
> Schon gehört? WEB.DE hat einen genialen Phishing-Filter in die
> Toolbar eingebaut! http://produkte.web.de/go/toolbar
> 


-- 
Jesse Barnes, Intel Open Source Technology Center

Re: gen6 (SNB) GPU still stalling besides latest patches

[Nicolas Kalkhof]

Hello!

sorry, setting i915.enable_rc6=0 didn't work for me. I've filed a bug:
https://bugs.freedesktop.org/show_bug.cgi?id=38529

thanks and regards
nico


-----Ursprüngliche Nachricht-----
Von: "Nicolas Kalkhof" <nkalkhof@web.de>
Gesendet: Jun 21, 2011 7:59:51 AM
An: intel-gfx@lists.freedesktop.org
Betreff: Re: [Intel-gfx] gen6 (SNB) GPU still stalling besides latest patches

>Hi Folks,
>ok, I'll give it a try this evening. Just one more thing: Should I pass enable_rc6 as a boot parameter like this: "i915.enable_rc6=0" or is it set by echoing sysfs (/sys/module/i915/parameters/...)?
>
>regards, nico
>
>
>-----Ursprüngliche Nachricht-----
>Von: "Jesse Barnes" <jbarnes@virtuousgeek.org>
>Gesendet: Jun 21, 2011 2:19:29 AM
>An: "Ted Phelps" <phelps@gnusto.com>
>Betreff: Re: [Intel-gfx] gen6 (SNB) GPU still stalling besides latest patches
>
>>On Tue, 21 Jun 2011 10:01:35 +1000
>>Ted Phelps <phelps@gnusto.com> wrote:
>>
>>>
>>> Hi Nicolas,
>>>
>>> Nicolas Kalkhof writes:
>>> > SNB GPU still hangs frequently with kernel patches next-20110620
>>> > raising "drm:i915_hangcheck_ring_idle *ERROR* Hangcheck timer
>>> > elapsed... gen6 bsd ring idle". This happens when multiple
>>> > applications (mplayer decoding vaapi stream and some openGL game)
>>> > running at the same time. With either one running there is no
>>> > stalling. Could someone please confirm the issue?
>>> >
>>> > /sys/module/i915/parameters/semaphores is set to 0
>>> > xf86-video-intel compiled with --enable-sna
>>>
>>> I haven't tried SNA, but I've seen GPU hangs as well (SNB 2600K). I've
>>> found that disabling RC6 (enable_rc6=0) seems to help. Can you see if
>>> that helps?
>>>
>>> [Note to self: submit a bug report]
>>
>>Please do; and please try to confirm that your GPU hangs are really rc6
>>related. RC6 provides a huge (multiple Watt) power savings, and we
>>really want it to be robust.
>>
>>--
>>Jesse Barnes, Intel Open Source Technology Center
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Re: gen6 (SNB) GPU still stalling besides latest patches

[Nicolas Kalkhof]

Hi Folks,
ok, I'll give it a try this evening. Just one more thing: Should I pass enable_rc6 as a boot parameter like this: "i915.enable_rc6=0" or is it set by echoing sysfs (/sys/module/i915/parameters/...)?

regards, nico


-----Ursprüngliche Nachricht-----
Von: "Jesse Barnes" <jbarnes@virtuousgeek.org>
Gesendet: Jun 21, 2011 2:19:29 AM
An: "Ted Phelps" <phelps@gnusto.com>
Betreff: Re: [Intel-gfx] gen6 (SNB) GPU still stalling besides latest patches

>On Tue, 21 Jun 2011 10:01:35 +1000
>Ted Phelps <phelps@gnusto.com> wrote:
>
>>
>> Hi Nicolas,
>>
>> Nicolas Kalkhof writes:
>> > SNB GPU still hangs frequently with kernel patches next-20110620
>> > raising "drm:i915_hangcheck_ring_idle *ERROR* Hangcheck timer
>> > elapsed... gen6 bsd ring idle". This happens when multiple
>> > applications (mplayer decoding vaapi stream and some openGL game)
>> > running at the same time. With either one running there is no
>> > stalling. Could someone please confirm the issue?
>> >
>> > /sys/module/i915/parameters/semaphores is set to 0
>> > xf86-video-intel compiled with --enable-sna
>>
>> I haven't tried SNA, but I've seen GPU hangs as well (SNB 2600K). I've
>> found that disabling RC6 (enable_rc6=0) seems to help. Can you see if
>> that helps?
>>
>> [Note to self: submit a bug report]
>
>Please do; and please try to confirm that your GPU hangs are really rc6
>related. RC6 provides a huge (multiple Watt) power savings, and we
>really want it to be robust.
>
>--
>Jesse Barnes, Intel Open Source Technology Center
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gen6 (SNB) GPU still stalling besides latest patches

[Nicolas Kalkhof]

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Re: gen6 (SNB) GPU still stalling besides latest patches

[Ted Phelps]

Hi Nicolas,

Nicolas Kalkhof writes:
> SNB GPU still hangs frequently with kernel patches next-20110620
> raising "drm:i915_hangcheck_ring_idle *ERROR* Hangcheck timer
> elapsed... gen6 bsd ring idle". This happens when multiple
> applications (mplayer decoding vaapi stream and some openGL game)
> running at the same time. With either one running there is no
> stalling. Could someone please confirm the issue?
>
> /sys/module/i915/parameters/semaphores is set to 0
> xf86-video-intel compiled with --enable-sna

I haven't tried SNA, but I've seen GPU hangs as well (SNB 2600K).  I've
found that disabling RC6 (enable_rc6=0) seems to help.  Can you see if
that helps?

[Note to self: submit a bug report]

Thanks,
-Ted

Re: gen6 (SNB) GPU still stalling besides latest patches

[Jesse Barnes]

On Tue, 21 Jun 2011 10:01:35 +1000
Ted Phelps <phelps@gnusto.com> wrote:

> 
> Hi Nicolas,
> 
> Nicolas Kalkhof writes:
> > SNB GPU still hangs frequently with kernel patches next-20110620
> > raising "drm:i915_hangcheck_ring_idle *ERROR* Hangcheck timer
> > elapsed... gen6 bsd ring idle". This happens when multiple
> > applications (mplayer decoding vaapi stream and some openGL game)
> > running at the same time. With either one running there is no
> > stalling. Could someone please confirm the issue?
> >
> > /sys/module/i915/parameters/semaphores is set to 0
> > xf86-video-intel compiled with --enable-sna
> 
> I haven't tried SNA, but I've seen GPU hangs as well (SNB 2600K).  I've
> found that disabling RC6 (enable_rc6=0) seems to help.  Can you see if
> that helps?
> 
> [Note to self: submit a bug report]

Please do; and please try to confirm that your GPU hangs are really rc6
related.  RC6 provides a huge (multiple Watt) power savings, and we
really want it to be robust.

-- 
Jesse Barnes, Intel Open Source Technology Center

Re: gen6 (SNB) GPU still stalling besides latest patches

[Ted Phelps]

Jesse Barnes writes:
> > [Note to self: submit a bug report]
> 
> Please do; and please try to confirm that your GPU hangs are really rc6
> related.  RC6 provides a huge (multiple Watt) power savings, and we
> really want it to be robust.

Done: BZ#38567.  I'd love to save those watts, so please let me know if
there's anything else I can do to help diagnose the issue.

Thanks,
-Ted