Bug 1219275

Summary:	nouveau: user interface slow (regression)
Product:	[openSUSE] openSUSE Tumbleweed	Reporter:	Arvin Schnell <aschnell>
Component:	Kernel	Assignee:	openSUSE Kernel Bugs <kernel-bugs>
Status:	RESOLVED FIXED	QA Contact:	E-mail List <qa-bugs>
Severity:	Normal
Priority:	P5 - None	CC:	aschnell, patrik.jakobsson, sndirsch, tiwai, tzimmermann
Version:	Current
Target Milestone:	---
Hardware:	x86-64
OS:	openSUSE Tumbleweed
Whiteboard:
Found By:	Development	Services Priority:
Business Priority:		Blocker:	---
Marketing QA Status:	---	IT Deployment:	---
Attachments:	dmesg and hwinfo

Description Arvin Schnell 2024-01-29 10:04:27 UTC

With the latest kernel-default 6.7.1-1.1 the user interface is slower
than before with 6.6.11-1.1. E.g. I can clearly see how windows are
redrawn (e.g. content of xterm).

I can pinpoint this to the kernel since booting the old kernel resolves
the problem.

System information:

Intel(R) Xeon(R) W-2123 CPU @ 3.60GHz
32 GiB RAM
NVIDIA Corporation GP107GL [Quadro P600] (rev a1) using nouveau

Comment 1 Takashi Iwai 2024-01-29 16:35:39 UTC

Could you give the dmesg outputs from both working and broken cases?
Also the hwinfo outputs from both, too.

Comment 2 Arvin Schnell 2024-01-29 16:53:16 UTC

Created attachment 872274 [details]
dmesg and hwinfo

Comment 3 Arvin Schnell 2024-01-29 17:10:09 UTC

Does the kernel 6.7 have a new schedule or caching? Because sometimes
e.g. a redraw is slow and sometimes fast.

Comment 4 Takashi Iwai 2024-01-29 17:14:58 UTC

Then it's rather changes in GPU scheduler. There has been significant reworks in 6.7.

You can try 6.8-rc2 kernel found in IBS Devel:Kernel:master repo.
This got a revert in nouveau.  I'm not sure whether it's relevant with your problem, but it's worth to try.

Comment 5 Takashi Iwai 2024-01-30 10:12:29 UTC

(In reply to Takashi Iwai from comment #4)
> You can try 6.8-rc2 kernel found in IBS Devel:Kernel:master repo.
> This got a revert in nouveau.  I'm not sure whether it's relevant with your
> problem, but it's worth to try.

And if the problem persists with 6.8-rc2, we should report this to the upstream,
gitlab issues DRM/nouveau:
  https://gitlab.freedesktop.org/drm/nouveau/-/issues

also report to the linux kernel regression:
  https://docs.kernel.org/admin-guide/reporting-regressions.html

Comment 6 Arvin Schnell 2024-01-30 14:34:58 UTC

After half a day of using 6.8-rc2 I can say that it works great again.

Comment 7 Takashi Iwai 2024-01-30 14:49:42 UTC

OK, it's a good news, at least.  But nouveau received lots of changes since 6.7, and it's hard to say which really fixed your problem; the changes including the significant scheduler changes in nouveau, and that might be the fix in your case.  Or it might be the last revert in 6.8-rc2...

As an easy try, I backported the patches with Cc-to-stable from 6.8.  There were three commits including the revert one I mentioned in the above.

The test kernel is being built in OBS home:tiwai:bsc1219275 repo.  Could you give it a try later, once after the build finishes?

Comment 8 Arvin Schnell 2024-01-31 14:05:50 UTC

The kernel 6.7.2 from home:tiwai:bsc1219275 also works great.

Comment 9 Takashi Iwai 2024-01-31 15:02:53 UTC

(In reply to Arvin Schnell from comment #8)
> The kernel 6.7.2 from home:tiwai:bsc1219275 also works great.

It's a good news!  Then I just need to merge those stable fixes for 6.7.
Will work on PR later.

Comment 10 Takashi Iwai 2024-01-31 16:35:09 UTC

Now the fix was pushed to my stable/for-next branch.  It'll be included in the future TW update kernel (maybe 6.7.3).  You can keep my test kernel until the fix kernel is released.

Comment 11 Takashi Iwai 2024-01-31 16:37:12 UTC

FWIW, the backported commits are:
205e18c13545ab43cc4fe4930732b4feef551198
 nouveau/gsp: handle engines in runl without nonstall interrupts.
cacea81390fd8c8c85404e5eb2adeb83d87a912e
 nouveau/vmm: don't set addr on the fail path to avoid warning
4d7acc8f48bcf27d0dc068f02e55c77e840b9110
 Revert "nouveau: push event block/allowing out of the fence context"