block: partition: convert percpu ref
authorMing Lei <tom.leiming@gmail.com>
Thu, 16 Jul 2015 03:16:45 +0000 (11:16 +0800)
committerJens Axboe <axboe@fb.com>
Fri, 17 Jul 2015 14:41:53 +0000 (08:41 -0600)
commit6c71013ecb7e2bddbed9f5b95e7aed22c491daa9
tree773a3ebe4289815e677ce2b357c665cba5292c0e
parentb54e5ed8f285d62c0d242c4ef9da90937994db02
block: partition: convert percpu ref

Percpu refcount is the perfect match for partition's case,
and the conversion is quite straight.

With the convertion, one pair of atomic inc/dec can be saved
for accounting block I/O, which is run in hot path of block I/O.

Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
block/genhd.c
block/partition-generic.c
include/linux/genhd.h