[Devel] [PATCH hci-8.1 4/4] sched: switch a sleeping task group entity between idle and iowait

[no-reply at sashiko.virtuozzo.com]

> A sleeping group entity is accounted as blocked if its cfs_rq had
> iowait sleepers when it was dequeued and as idle otherwise. But
> nr_iowait can change while the group sleeps, e.g. when its iowait task
> wakes up on another CPU, moves to another cgroup or changes its class.
> The group then keeps accounting iowait on a CPU where nothing waits
> for IO anymore.
> 
> Fix it like vz7 nr_iowait_{inc,dec}_fair() did: when nr_iowait changes,
> close the current period of the sleeping group and start the other
> kind. This needs an up to date rq clock, so update it in the migrating
> wakeup path of try_to_wake_up(). The other callers already do it.
> 
> https://virtuozzo.atlassian.net/browse/VSTOR-147823
> Signed-off-by: Vasileios Almpanis <vasileios.almpanis at virtuozzo.com>

Sashiko has reviewed this patch and found no issues. It looks great!

-- 
Sashiko AI review · https://sashiko.vzint.dev/#/patchset/20261014-ct-iowait-v1-0-9d65fe37cf89@virtuozzo.com?part=4