On Wed, 5 Feb 2014, Ivan Khoronzhuk wrote:

+	/* here we have to be sure the timer has been disabled */

Sigh. This is not a proper explanation for a barrier, really. You want
to explain what it serializes against what. i.e. you want to explain
why you are using the relaxed functions and avoid a separate non
relaxed variant in favour of an explicit barrier.

+	__iowmb();

The proper thing is to have an inline function key_stone_barrier() and
a full explanation of the issue in exactly that place instead of
handwaving comments here and there.

Thanks,

	tglx