Messages in this thread | | | Date | Tue, 6 Jan 2015 04:45:28 -0800 | From | Kent Overstreet <> | Subject | Re: Linux 3.19-rc3 |
| |
On Tue, Jan 06, 2015 at 01:20:06PM +0100, Peter Zijlstra wrote: > We (probably me) should probably audit all the atomic_xchg() > implementations and documentation and fix that. I was very much under > the impression it should imply a full barrier (and it certainly does on > x86), the documentation should state the rule that any atomic_ function > that returns a result is fully serializing, therefore, because > atomic_xchg() has a return value, it should too.
I think that the documentation was changed awhile ago - I'd have to check and I should sleep, though. It was probably 4-5 years ago that I saw that old weird "atomic_xchg() doesn't imply barriers" thing.
| |