Re: [RFC PATCH 1/2] lib/percpu-list: Per-cpu list with associated per-cpu locks

[Christoph Lameter]

On Wed, 17 Feb 2016, Waiman Long wrote:

> I know we can use RCU for singly linked list, but I don't think we can use
> that for doubly linked list as there is no easy way to make atomic changes to
> both prev and next pointers simultaneously unless you are taking about 16b
> cmpxchg which is only supported in some architecture.

But its supported in the most important architecutes. You can fall back to
spinlocks on the ones that do not support it.