Hi Linus, I'm not sure how relevant it is to the topic, but I seem to remember you having a go at implementing spinlocks with x86_64 memory transaction instructions a while back. Do you have any thoughts on whether these instructions are ever likely to become something we can use? I was looking specifically at the skbuff queue stuff which does { spin_lock_irq, add to list, inc count, spin_unlock_irq } and thinking that might be a good place to use such a thing. David