Re: [PATCH] md/raid5: play nice with PREEMPT_RT

[Song Liu]

On Mon, Nov 15, 2021 at 5:23 PM Davidlohr Bueso <dave@xxxxxxxxxxxx> wrote:
>
> raid_run_ops() relies on the implicitly disabled preemption for
> its percpu ops, although this is really about CPU locality. This
> breaks RT semantics as it can take regular (and thus sleeping)
> spinlocks, such as stripe_lock.
>
> Add a local_lock such that non-RT does not change and continues
> to be just map to preempt_disable/enable, but makes RT happy as
> the region will use a per-CPU spinlock and thus be preemptible
> and still guarantee CPU locality.
>
> Signed-off-by: Davidlohr Bueso <dbueso@xxxxxxx>

Applied to md-next.

Thanks,
Song