Re: SMP syncronization on AMD processors (broken?)

[Linus Torvalds]

On Thu, 6 Oct 2005, Andrey Savochkin wrote:
> 
> Well, it's hard to swallow...
> It's not about being not fully fair, it's about deadlocks that started
> to appear after code changes inside retry loops...

No, it's not about fairness.

It's about BUGS IN YOUR CODE.

If you need fairness, you need to implement that yourself. You can do so 
many ways. Either on top of spinlocks, by using an external side-band 
channel, or by using semaphores instead of spinlocks (semaphores are much 
higher cost, but part of the cost is that they _are_ fair).

		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/