diff options
| author | NeilBrown <neilb@suse.de> | 2006-10-03 01:15:54 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-10-03 08:04:18 -0700 |
| commit | 0d12922823408b26f83b15cae4a4feff4bd22f28 (patch) | |
| tree | a3509f442e6fc75ca9304757ffa3dce4918ef55e /drivers/md/raid1.c | |
| parent | 26be34dc3a46be983352dd89683db374b0cb73fa (diff) | |
[PATCH] md: define ->congested_fn for raid1, raid10, and multipath
raid1, raid10 and multipath don't report their 'congested' status through
bdi_*_congested, but should.
This patch adds the appropriate functions which just check the 'congested'
status of all active members (with appropriate locking).
raid1 read_balance should be modified to prefer devices where
bdi_read_congested returns false. Then we could use the '&' branch rather
than the '|' branch. However that should would need some benchmarking first
to make sure it is actually a good idea.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'drivers/md/raid1.c')
| -rw-r--r-- | drivers/md/raid1.c | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index 99c4e031c7f..dc9d2def027 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -601,6 +601,32 @@ static int raid1_issue_flush(request_queue_t *q, struct gendisk *disk, return ret; } +static int raid1_congested(void *data, int bits) +{ + mddev_t *mddev = data; + conf_t *conf = mddev_to_conf(mddev); + int i, ret = 0; + + rcu_read_lock(); + for (i = 0; i < mddev->raid_disks; i++) { + mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[i].rdev); + if (rdev && !test_bit(Faulty, &rdev->flags)) { + request_queue_t *q = bdev_get_queue(rdev->bdev); + + /* Note the '|| 1' - when read_balance prefers + * non-congested targets, it can be removed + */ + if ((bits & (1<<BDI_write_congested)) || 1) + ret |= bdi_congested(&q->backing_dev_info, bits); + else + ret &= bdi_congested(&q->backing_dev_info, bits); + } + } + rcu_read_unlock(); + return ret; +} + + /* Barriers.... * Sometimes we need to suspend IO while we do something else, * either some resync/recovery, or reconfigure the array. @@ -1965,6 +1991,8 @@ static int run(mddev_t *mddev) mddev->queue->unplug_fn = raid1_unplug; mddev->queue->issue_flush_fn = raid1_issue_flush; + mddev->queue->backing_dev_info.congested_fn = raid1_congested; + mddev->queue->backing_dev_info.congested_data = mddev; return 0; |