Re: [RFC PATCH] Writer-biased low-latency rwlock v8

Linus Torvalds
2008-08-23T18:03:43Z

On Sat, 23 Aug 2008, Mathieu Desnoyers wrote:
>
> Now, let me explain why I need at least not one, but _four different_
> contention bits. Simply because there are four types of contention, one
> for each execution context which may take the read lock. (irq, softirq,
> non-preemptable, preemptable)

No. You need _one_ contention bit in the fast-path.

Then, as you get into the slow-path, you can decide on four different
behaviours.

Quite frankly, I don't think this discussion is going anywhere. I don't
think I'd take anything from you, since you seem to have a really hard
time separating out the issue of fast-path and slow-path. So I'm simply
not going to bother, and I'm not going to expect to merge your work.

Sorry, but it simply isn't worth my time or effort.

Linus