Re: [PATCH v2] sched: async unthrottling for cfs bandwidth

[Josh Don]

On Wed, Nov 2, 2022 at 9:59 AM Michal Koutný <mkoutny@xxxxxxxx> wrote:
>
> Also, can a particular cfs_rq be on both cfs_b->throttled_csd_list and
> cfs_b->throttled_cfs_rq lists at any moment?
> I wonder if having a single list_head node in cfs_rq would be feasible
> (and hence enforcing this constraint in data).

After more thought, I realized that we can't reuse the throttled_list
list_head, since that would potentially break the lockless traversal
of a concurrent list_for_each_entry_rcu() (ie. if we removed the
element from the throttled list and then added it to the CSD list).

- Josh