[PATCH] md: add a ->congested_fn function for raid5/6

This is very different from other raid levels and all requests go through a
'stripe cache', and it has congestion management already.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
NeilBrown 2006-10-03 01:15:56 -07:00 committed by Linus Torvalds
parent 0d12922823
commit f022b2fddd

View File

@ -2593,6 +2593,24 @@ static int raid5_issue_flush(request_queue_t *q, struct gendisk *disk,
return ret;
}
static int raid5_congested(void *data, int bits)
{
mddev_t *mddev = data;
raid5_conf_t *conf = mddev_to_conf(mddev);
/* No difference between reads and writes. Just check
* how busy the stripe_cache is
*/
if (conf->inactive_blocked)
return 1;
if (conf->quiesce)
return 1;
if (list_empty_careful(&conf->inactive_list))
return 1;
return 0;
}
static int make_request(request_queue_t *q, struct bio * bi)
{
mddev_t *mddev = q->queuedata;
@ -3296,6 +3314,9 @@ static int run(mddev_t *mddev)
mddev->queue->unplug_fn = raid5_unplug_device;
mddev->queue->issue_flush_fn = raid5_issue_flush;
mddev->queue->backing_dev_info.congested_fn = raid5_congested;
mddev->queue->backing_dev_info.congested_data = mddev;
mddev->array_size = mddev->size * (conf->previous_raid_disks -
conf->max_degraded);