From mboxrd@z Thu Jan 1 00:00:00 1970 From: NeilBrown Subject: [PATCH 003 of 4] md: Add a ->congested_fn function for raid5/6 Date: Tue, 29 Aug 2006 15:39:48 +1000 Message-ID: <1060829053948.6646@suse.de> References: <20060829153414.6475.patches@notabene> Return-path: Sender: linux-raid-owner@vger.kernel.org To: Andrew Morton Cc: linux-raid@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-raid.ids 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 ### Diffstat output ./drivers/md/raid5.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff .prev/drivers/md/raid5.c ./drivers/md/raid5.c --- .prev/drivers/md/raid5.c 2006-08-29 14:57:09.000000000 +1000 +++ ./drivers/md/raid5.c 2006-08-29 14:57:05.000000000 +1000 @@ -2593,6 +2593,24 @@ static int raid5_issue_flush(request_que 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);