On Fri, Apr 19, 2019 at 02:02:07PM +0200, Peter Zijlstra wrote: > On Fri, Apr 19, 2019 at 12:26:47PM +0200, Peter Zijlstra wrote: > > I thought of a horrible horrible alternative: > > Hurm, that's broken as heck. Let me try again.
So I can't make that scheme work, it all ends up wanting to have cmpxchg(). Do we have a performance comparison somewhere of xadd vs cmpxchg readers? I tried looking in the old threads, but I can't seem to locate it. We need new instructions :/ Or more clever than I can muster just now.
