Re: [tip:core/printk] ratelimit: Fix/allow use in atomic contexts
From: Linus Torvalds
Date: Tue Sep 22 2009 - 10:47:35 EST
On Tue, 22 Sep 2009, tip-bot for Ingo Molnar wrote:
>
> ratelimit: Fix/allow use in atomic contexts
>
> I'd like to use printk_ratelimit() in NMI context, but it's not
> robust right now due to spinlock usage in lib/ratelimit.c. If an
> NMI is unlucky enough to hit just that spot we might lock up trying
> to take the spinlock again.
>
> Fix that by using a trylock variant. If we contend on that lock we
> can genuinely skip the message because the state is just being
> accessed by another CPU (or by this CPU).
Ack to both this and the patch leading up to it. Looks sane and simple.
Linus
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/