On Mon, Mar 06, 2017 at 09:03:26PM -0800, Davidlohr Bueso wrote: > +++ b/kernel/locking/range_rwlock.c > @@ -0,0 +1,462 @@ > +/* > + * Implementation of read/write range locks. > + * > + * We keep interval tree of locked and to-be-locked ranges. When new range > lock > + * is requested, we add its interval to the tree and store number of > intervals > + * intersecting it to 'blocking_ranges'. > + * > + * When a range is unlocked, we again walk intervals that intersect with the > + * unlocked one and decrement their 'blocking_ranges'. We wake up owner of > any > + * range lock whose 'blocking_ranges' drops to 0. For the shared case, the > + * 'blocking_ranges' is only incremented if the intersecting range is not > marked > + * as a reader. In order to mitigate some of the tree walk overhead for > + * non-intersecting ranges, the tree's min/max values are maintained and > consulted > + * in O(1) in the fastpath. > + */
Was your editor broken? Those lines are > 80 for no reason what so ever.
