K 10
svn:author
V 3
mjg
K 8
svn:date
V 27
2014-10-04T08:03:52.730919Z
K 7
svn:log
V 204
Add sequence counters with memory barriers.

Current implementation is somewhat simplistic and hackish,
will be improved later after possible memory barrier overhaul.

Reviewed by:	kib
MFC after:	3 weeks

END