[BLOCK] Unify the seperate read/write io stat fields into arrays
Instead of having ->read_sectors and ->write_sectors, combine the two
into ->sectors[2] and similar for the other fields. This saves a branch
several places in the io path, since we don't have to care for what the
actual io direction is. On my x86-64 box, that's 200 bytes less text in
just the core (not counting the various drivers).
Signed-off-by: Jens Axboe <axboe@suse.de>
diff --git a/drivers/md/multipath.c b/drivers/md/multipath.c
index 1151c3e..c06f4474 100644
--- a/drivers/md/multipath.c
+++ b/drivers/md/multipath.c
@@ -168,6 +168,7 @@
multipath_conf_t *conf = mddev_to_conf(mddev);
struct multipath_bh * mp_bh;
struct multipath_info *multipath;
+ const int rw = bio_data_dir(bio);
if (unlikely(bio_barrier(bio))) {
bio_endio(bio, bio->bi_size, -EOPNOTSUPP);
@@ -179,13 +180,8 @@
mp_bh->master_bio = bio;
mp_bh->mddev = mddev;
- if (bio_data_dir(bio)==WRITE) {
- disk_stat_inc(mddev->gendisk, writes);
- disk_stat_add(mddev->gendisk, write_sectors, bio_sectors(bio));
- } else {
- disk_stat_inc(mddev->gendisk, reads);
- disk_stat_add(mddev->gendisk, read_sectors, bio_sectors(bio));
- }
+ disk_stat_inc(mddev->gendisk, ios[rw]);
+ disk_stat_add(mddev->gendisk, sectors[rw], bio_sectors(bio));
mp_bh->path = multipath_map(conf);
if (mp_bh->path < 0) {