Re: Error: psi: inconsistent task state! task=1:swapper/0 cpu=0 psi_flags=4 clear=0 set=4

[Johannes Weiner]

On Sun, Sep 22, 2024 at 08:53:37AM +0200, Paul Menzel wrote:
> [Cc: +PSI maintainers]
> 
> Am 22.09.24 um 00:50 schrieb Paul Menzel:
> > #regzbot introduced: 2e0199df252a..54a58a787791
> > 
> > Dear Peter,
> > 
> > 
> > With merge commit 2004cef11ea0 (Merge tag 'sched-core-2024-09-19' of 
> > git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip) I see the warning 
> > below on the Intel Kaby Lake laptop Dell XPS 13 9360 and with QEMU.
> > 
> > Dell XPS 13 9360:
> > 
> >      psi: inconsistent task state! task=1:swapper/0 cpu=0 psi_flags=4 clear=0 set=4

Oh, double enqueue.

It looks like the psi enqueue/dequeue callbacks need the same
treatment as the uclamp and sched_core ones for ignoring delayed
tasks. [1][2]

Do we need to reorder psi_enqueue() after ->enqueue_task() as well? I
can't quite work out why uclamp needed it, but sched_core didn't.

[1] dfa0a574cbc47bfd5f8985f74c8ea003a37fa078
[2] c662e2b1e8cfc3b6329704dab06051f8c3ec2993