On Tue, Oct 13, 2015 at 04:04:27PM +0100, Will Deacon wrote:

On Tue, Oct 13, 2015 at 10:58:30PM +0800, Boqun Feng wrote:

quoted

On Tue, Oct 13, 2015 at 03:43:33PM +0100, Will Deacon wrote:

quoted

Putting a barrier in the middle of that critical section is probably a
terrible idea, and that's why I thought you were avoiding it (hence my

The fact is that I haven't thought of that way to implement
cmpxchg_release before you ask that question ;-) And I'm not going to do
that for now and probably not in the future.

quoted

original question). Perhaps just add a comment to that effect, since I

Are you suggesting if I put a barrier in the middle I'd better to add a
comment, right? So if I don't do that, it's OK to let this patch as it.

No, I mean put a comment in your file to explain the reason why you
override _relaxed and _acquire, but not _release (because overriding
_release would introduce this weird barrier in the middle of the critical
section, which would likely cause the conditional store to fail).

Good idea, will do that. Thank you ;-)

Regards,
Boqun