From 269f541555d8f5da322d592fb3e13e23ed62d80c Mon Sep 17 00:00:00 2001 From: Vivek Goyal Date: Thu, 19 May 2011 15:38:25 -0400 Subject: [PATCH] blk-throttle: Introduce a helper function to fill in device details A helper function for the code which is used at 2-3 places. Makes reading code little easier. Signed-off-by: Vivek Goyal Signed-off-by: Jens Axboe --- block/blk-throttle.c | 35 +++++++++++++++++++++++------------ 1 file changed, 23 insertions(+), 12 deletions(-) diff --git a/block/blk-throttle.c b/block/blk-throttle.c index 68f2ac3..97ea7f8 100644 --- a/block/blk-throttle.c +++ b/block/blk-throttle.c @@ -188,16 +188,34 @@ throtl_add_group_to_td_list(struct throtl_data *td, struct throtl_grp *tg) td->nr_undestroyed_grps++; } -static void throtl_init_add_tg_lists(struct throtl_data *td, - struct throtl_grp *tg, struct blkio_cgroup *blkcg) +static void +__throtl_tg_fill_dev_details(struct throtl_data *td, struct throtl_grp *tg) { struct backing_dev_info *bdi = &td->queue->backing_dev_info; unsigned int major, minor; + if (!tg || tg->blkg.dev) + return; + + /* + * Fill in device details for a group which might not have been + * filled at group creation time as queue was being instantiated + * and driver had not attached a device yet + */ + if (bdi->dev && dev_name(bdi->dev)) { + sscanf(dev_name(bdi->dev), "%u:%u", &major, &minor); + tg->blkg.dev = MKDEV(major, minor); + } +} + +static void throtl_init_add_tg_lists(struct throtl_data *td, + struct throtl_grp *tg, struct blkio_cgroup *blkcg) +{ + __throtl_tg_fill_dev_details(td, tg); + /* Add group onto cgroup list */ - sscanf(dev_name(bdi->dev), "%u:%u", &major, &minor); blkiocg_add_blkio_group(blkcg, &tg->blkg, (void *)td, - MKDEV(major, minor), BLKIO_POLICY_THROTL); + tg->blkg.dev, BLKIO_POLICY_THROTL); tg->bps[READ] = blkcg_get_read_bps(blkcg, tg->blkg.dev); tg->bps[WRITE] = blkcg_get_write_bps(blkcg, tg->blkg.dev); @@ -225,8 +243,6 @@ throtl_grp *throtl_find_tg(struct throtl_data *td, struct blkio_cgroup *blkcg) { struct throtl_grp *tg = NULL; void *key = td; - struct backing_dev_info *bdi = &td->queue->backing_dev_info; - unsigned int major, minor; /* * This is the common case when there are no blkio cgroups. @@ -237,12 +253,7 @@ throtl_grp *throtl_find_tg(struct throtl_data *td, struct blkio_cgroup *blkcg) else tg = tg_of_blkg(blkiocg_lookup_group(blkcg, key)); - /* Fill in device details for root group */ - if (tg && !tg->blkg.dev && bdi->dev && dev_name(bdi->dev)) { - sscanf(dev_name(bdi->dev), "%u:%u", &major, &minor); - tg->blkg.dev = MKDEV(major, minor); - } - + __throtl_tg_fill_dev_details(td, tg); return tg; } -- 2.7.4