[md PATCH 10/18] md/raid1: small cleanup in raid1_end_read/write_request

NeilBrown
2016-06-02T06:19:52Z

Both functions use conf->mirrors[mirror].rdev several times, so
improve readability by storing this in a local variable.

Signed-off-by: NeilBrown <neilb@suse.com>
---
drivers/md/raid1.c | 35 +++++++++++++++--------------------
1 file changed, 15 insertions(+), 20 deletions(-)

diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index a54edbe741ff..9585a6b62123 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -319,14 +319,13 @@ static void raid1_end_read_request(struct bio *bio)
{
int uptodate = !bio->bi_error;
struct r1bio *r1_bio = bio->bi_private;
- int mirror;
struct r1conf *conf = r1_bio->mddev->private;
+ struct md_rdev *rdev = conf->mirrors[r1_bio->read_disk].rdev;

- mirror = r1_bio->read_disk;
/*
* this branch is our 'one mirror IO has finished' event handler:
*/
- update_head_pos(mirror, r1_bio);
+ update_head_pos(r1_bio->read_disk, r1_bio);

if (uptodate)
set_bit(R1BIO_Uptodate, &r1_bio->state);
@@ -339,14 +338,14 @@ static void raid1_end_read_request(struct bio *bio)
spin_lock_irqsave(&conf->device_lock, flags);
if (r1_bio->mddev->degraded == conf->raid_disks ||
(r1_bio->mddev->degraded == conf->raid_disks-1 &&
- test_bit(In_sync, &conf->mirrors[mirror].rdev->flags)))
+ test_bit(In_sync, &rdev->flags)))
uptodate = 1;
spin_unlock_irqrestore(&conf->device_lock, flags);
}

if (uptodate) {
raid_end_bio_io(r1_bio);
- rdev_dec_pending(conf->mirrors[mirror].rdev, conf->mddev);
+ rdev_dec_pending(rdev, conf->mddev);
} else {
/*
* oops, read error:
@@ -356,7 +355,7 @@ static void raid1_end_read_request(struct bio *bio)
KERN_ERR "md/raid1:%s: %s: "
"rescheduling sector %llu\n",
mdname(conf->mddev),
- bdevname(conf->mirrors[mirror].rdev->bdev,
+ bdevname(rdev->bdev,
b),
(unsigned long long)r1_bio->sector);
set_bit(R1BIO_ReadError, &r1_bio->state);
@@ -403,20 +402,18 @@ static void r1_bio_write_done(struct r1bio *r1_bio)
static void raid1_end_write_request(struct bio *bio)
{
struct r1bio *r1_bio = bio->bi_private;
- int mirror, behind = test_bit(R1BIO_BehindIO, &r1_bio->state);
+ int behind = test_bit(R1BIO_BehindIO, &r1_bio->state);
struct r1conf *conf = r1_bio->mddev->private;
struct bio *to_put = NULL;
-
- mirror = find_bio_disk(r1_bio, bio);
+ int mirror = find_bio_disk(r1_bio, bio);
+ struct md_rdev *rdev = conf->mirrors[mirror].rdev;

/*
* 'one mirror IO has finished' event handler:
*/
if (bio->bi_error) {
- set_bit(WriteErrorSeen,
- &conf->mirrors[mirror].rdev->flags);
- if (!test_and_set_bit(WantReplacement,
- &conf->mirrors[mirror].rdev->flags))
+ set_bit(WriteErrorSeen, &rdev->flags);
+ if (!test_and_set_bit(WantReplacement, &rdev->flags))
set_bit(MD_RECOVERY_NEEDED, &
conf->mddev->recovery);

@@ -445,13 +442,12 @@ static void raid1_end_write_request(struct bio *bio)
* before rdev->recovery_offset, but for simplicity we don't
* check this here.
*/
- if (test_bit(In_sync, &conf->mirrors[mirror].rdev->flags) &&
- !test_bit(Faulty, &conf->mirrors[mirror].rdev->flags))
+ if (test_bit(In_sync, &rdev->flags) &&
+ !test_bit(Faulty, &rdev->flags))
set_bit(R1BIO_Uptodate, &r1_bio->state);

/* Maybe we can clear some bad blocks. */
- if (is_badblock(conf->mirrors[mirror].rdev,
- r1_bio->sector, r1_bio->sectors,
+ if (is_badblock(rdev, r1_bio->sector, r1_bio->sectors,
&first_bad, &bad_sectors)) {
r1_bio->bios[mirror] = IO_MADE_GOOD;
set_bit(R1BIO_MadeGood, &r1_bio->state);
@@ -459,7 +455,7 @@ static void raid1_end_write_request(struct bio *bio)
}

if (behind) {
- if (test_bit(WriteMostly, &conf->mirrors[mirror].rdev->flags))
+ if (test_bit(WriteMostly, &rdev->flags))
atomic_dec(&r1_bio->behind_remaining);

/*
@@ -483,8 +479,7 @@ static void raid1_end_write_request(struct bio *bio)
}
}
if (r1_bio->bios[mirror] == NULL)
- rdev_dec_pending(conf->mirrors[mirror].rdev,
- conf->mddev);
+ rdev_dec_pending(rdev, conf->mddev);

/*
* Let's see if all mirrored write operations have finished