Re: [linux-audio-dev] Re: [announce] [patch] Voluntary Kernel Preemption Patch

Andrew Morton
2004-09-02T22:27:22Z

Andrea Arcangeli <andrea@suse.de> wrote:
>
> if you're scared that there are too many cond_resched (I'm not scared
> and people should enable them anyways if they make a difference, they
> still should be less than the number of spin_unlocks with preempt
> enabled), then you should add a cond_resched_costly and add a config
> option that turns it off.

None of these approaches improves worst-case latency at all on SMP. If
we're not going to address the SMP problem we could just make it UP-only,
in which case increased locking costs are a non-issue.

I'd prefer that we find a solution for SMP too though.