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authorTejun Heo <tj@kernel.org>2012-04-13 13:11:32 -0700
committerJens Axboe <axboe@kernel.dk>2012-04-20 10:06:06 +0200
commit03d8e11142a893ad322285d3c8a08e88b570cda1 (patch)
tree0f6117ffdb0ad9565a165a98a8d4985ced094eb1 /block
parentb82d4b197c782ced82a8b7b76664125d2d3c156c (diff)
downloadlinux-03d8e11142a893ad322285d3c8a08e88b570cda1.tar.bz2
blkcg: add request_queue->root_blkg
With per-queue policy activation, root blkg creation will be moved to blkcg core. Add q->root_blkg in preparation. For blk-throtl, this replaces throtl_data->root_tg; however, cfq needs to keep cfqd->root_group for !CONFIG_CFQ_GROUP_IOSCHED. This is to prepare for per-queue policy activation and doesn't cause any functional difference. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block')
-rw-r--r--block/blk-throttle.c16
-rw-r--r--block/cfq-iosched.c4
2 files changed, 13 insertions, 7 deletions
diff --git a/block/blk-throttle.c b/block/blk-throttle.c
index 6f1bfdf9a1b7..8c520fad6885 100644
--- a/block/blk-throttle.c
+++ b/block/blk-throttle.c
@@ -97,7 +97,6 @@ struct throtl_data
/* service tree for active throtl groups */
struct throtl_rb_root tg_service_tree;
- struct throtl_grp *root_tg;
struct request_queue *queue;
/* Total Number of queued bios on READ and WRITE lists */
@@ -131,6 +130,11 @@ static inline struct blkio_group *tg_to_blkg(struct throtl_grp *tg)
return pdata_to_blkg(tg);
}
+static inline struct throtl_grp *td_root_tg(struct throtl_data *td)
+{
+ return blkg_to_tg(td->queue->root_blkg);
+}
+
enum tg_state_flags {
THROTL_TG_FLAG_on_rr = 0, /* on round-robin busy list */
};
@@ -261,7 +265,7 @@ throtl_grp *throtl_lookup_tg(struct throtl_data *td, struct blkio_cgroup *blkcg)
* Avoid lookup in this case
*/
if (blkcg == &blkio_root_cgroup)
- return td->root_tg;
+ return td_root_tg(td);
return blkg_to_tg(blkg_lookup(blkcg, td->queue));
}
@@ -277,7 +281,7 @@ static struct throtl_grp *throtl_lookup_create_tg(struct throtl_data *td,
* Avoid lookup in this case
*/
if (blkcg == &blkio_root_cgroup) {
- tg = td->root_tg;
+ tg = td_root_tg(td);
} else {
struct blkio_group *blkg;
@@ -287,7 +291,7 @@ static struct throtl_grp *throtl_lookup_create_tg(struct throtl_data *td,
if (!IS_ERR(blkg))
tg = blkg_to_tg(blkg);
else if (!blk_queue_dead(q))
- tg = td->root_tg;
+ tg = td_root_tg(td);
}
return tg;
@@ -1245,12 +1249,12 @@ int blk_throtl_init(struct request_queue *q)
blkg = blkg_lookup_create(&blkio_root_cgroup, q, true);
if (!IS_ERR(blkg))
- td->root_tg = blkg_to_tg(blkg);
+ q->root_blkg = blkg;
spin_unlock_irq(q->queue_lock);
rcu_read_unlock();
- if (!td->root_tg) {
+ if (!q->root_blkg) {
kfree(td);
return -ENOMEM;
}
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index de95f9a2acf8..86440e04f3ee 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -3964,8 +3964,10 @@ static int cfq_init_queue(struct request_queue *q)
spin_lock_irq(q->queue_lock);
blkg = blkg_lookup_create(&blkio_root_cgroup, q, true);
- if (!IS_ERR(blkg))
+ if (!IS_ERR(blkg)) {
+ q->root_blkg = blkg;
cfqd->root_group = blkg_to_cfqg(blkg);
+ }
spin_unlock_irq(q->queue_lock);
rcu_read_unlock();