Re: [PATCH 3/5] sched: Change rcu_dereference_check_sched_domain() to rcu-sched

Peter Zijlstra
2025-11-28T10:57:31Z

On Thu, Nov 27, 2025 at 04:39:46PM +0100, Peter Zijlstra wrote:
> By changing rcu_dereference_check_sched_domain() to use
> rcu_dereference_sched_check() it also considers preempt_disable() to
> be equivalent to rcu_read_lock().
>
> Since rcu fully implies rcu_sched this has absolutely no change in
> behaviour, but it does allow removing a bunch of otherwise redundant
> rcu_read_lock() noise.

This goes sideways with NUMABALANCING=y, it needs a little more. I'll
have a poke.