Re: [PATCH 2.6.13] lockless pagecache 2/7

Alan Cox
2005-09-03T17:08:01Z

On Sad, 2005-09-03 at 11:40 +1000, Nick Piggin wrote:
> We'll see how things go. I'm fairly sure that for my usage it will
> be a win even if it is costly. It is replacing an atomic_inc_return,
> and a read_lock/read_unlock pair.

Make sure you bench both AMD and Intel - I'd expect it to be a big loss
on AMD because the AMD stuff will perform atomic locked operations very
efficiently if they are already exclusive on this CPU or a prefetch_w()
on them was done 200+ clocks before.