Re: [PATCH 8/5] llist: Remove cpu_relax() usage in cmpxchg loops

Peter Zijlstra
2011-09-13T14:22:35Z

On Tue, 2011-09-13 at 14:43 +0300, Avi Kivity wrote:

> Another issue is that hypervisors use PAUSE to detect a spinning guest
> and issue a directed yield to another vcpu. But for cmpxchg loops, the
> "spinner" would just commit on the next loop, no? So I think there's no
> objection from that front.

Right, we shouldn't ever spend a significant amount spinning on a
cmpxchg. If we do we need to fix that instead.