Re: [PATCH] sched/schedutil: Fix deadlock between cpuset and cpu hotplug when using schedutil

[Xuewen Yan]

Dear all

On Wed, Jul 13, 2022 at 11:20 AM Tejun Heo <tj@xxxxxxxxxx> wrote:
>
> On Tue, Jul 12, 2022 at 10:49:57PM -0400, Waiman Long wrote:
> > > Well, the only thing I can think of is always grabbing cpus_read_lock()
> > > before grabbing threadgroup_rwsem. Waiman, what do you think?
> >
> > That is a possible solution as cpus_read_lock() is rather lightweight. It is
> > a good practice to acquire it first.
>
> On a similar note, I think we probably should re-enable percpu operations on
> threadgroup_rwsem too by default and allow users who are affected by slower
> write path operations to opt-in. After the new CLONE_INTO_CGROUP which
> doesn't need the rwsem, we have far fewer write lockers after all.
>

 If there's any patch for me to try? I would be very grateful.

Thanks!

---
xw.yan