Jens Axboe 4a893e837b [PATCH] elevator: define ioc counting mechanism
None of the in-kernel primitives for handling "atomic" counting seem
to be a good fit. We need something that is essentially free for
incrementing/decrementing, while the read side may be more expensive
as we only ever need to do that when a device is removed from the
kernel.

Use a per-cpu variable for maintaining a per-cpu ioc count and define
a reading mechanism that just sums up the values.

Signed-off-by: Jens Axboe <axboe@suse.de>
2006-09-30 20:29:36 +02:00
..
2006-09-29 09:18:04 -07:00