Re: [powerpc][next-20210621] WARNING at kernel/sched/fair.c:3277 during boot

On Wed, 23 Jun 2021 at 14:37, Odin Ugedal [off-list ref] wrote:

ons. 23. jun. 2021 kl. 14:22 skrev Vincent Guittot [off-list ref]:

quoted

In theory it should not because _sum should be always larger or equal
to _avg * divider. Otherwise, it means that we have something wrong
somewhere else

Yeah, that might be the case. Still trying to wrap my head around
this. I might be wrong, but isn't there a possibility
that avg->period_contrib is increasing in PELTs accumulate_sum,
without _sum is increasing. This makes the pelt divider increase,
making the statement "_sum should be always larger or equal to _avg *"
false? Or am I missing something obvious here?

The pelt value of sched_entity is synced with  cfs and its contrib
before being removed.
Then, we start to remove this load in update_cfs_rq_load_avg() before
calling __update_load_avg_cfs_rq so contrib should not have change and
we should be safe

Still unable to reproduce what Sachin is reporting tho.

Odin