Re: net/sched: latent livelock in dev_deactivate_many() due to yield() usage

[Cong Wang]

On Tue, Apr 4, 2017 at 8:20 PM, Mike Galbraith <efault@xxxxxx> wrote:
> -               while (some_qdisc_is_busy(dev))
> -                       yield();
> +               swait_event_timeout(swait, !some_qdisc_is_busy(dev), 1);
>  }

I don't see why this is an improvement even if I don't care about the
hardcoded timeout for now... Why the scheduler can make a better
decision with swait_event_timeout() than with cond_resched()?