Re: [PATCH v7 4/7] sched/core: Prevent race condition between cpuset and __sched_setscheduler()

From: Peter Zijlstra
Date: Fri Apr 05 2019 - 08:37:09 EST


On Wed, Apr 03, 2019 at 10:46:47AM +0200, Juri Lelli wrote:
> +static inline void cpuset_read_only_lock(unsigned long *flags)
> +{
> + local_irq_save(*flags);
> + preempt_disable();
> +}
> +
> +static inline void cpuset_read_only_unlock(unsigned long *flags)
> +{
> + local_irq_restore(*flags);
> + preempt_enable();
> +}

You can ditch the preempt stuff. IRQs disabled already very much implies
!preemptible.