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authorDennis Zhou <dennis@kernel.org>2018-11-01 17:24:10 -0400
committerJens Axboe <axboe@kernel.dk>2018-11-01 19:59:53 -0600
commitb5f2954d30c77649bce9c27e7a0a94299d9cfdf8 (patch)
treef5dd932dc087c3a60410e82c70be1daf92d350a7 /block
parent153fcd5f6d93b8e1e4040b1337f564a10f8d93af (diff)
downloadlinux-b5f2954d30c77649bce9c27e7a0a94299d9cfdf8.tar.bz2
blkcg: revert blkcg cleanups series
This reverts a series committed earlier due to null pointer exception bug report in [1]. It seems there are edge case interactions that I did not consider and will need some time to understand what causes the adverse interactions. The original series can be found in [2] with a follow up series in [3]. [1] https://www.spinics.net/lists/cgroups/msg20719.html [2] https://lore.kernel.org/lkml/20180911184137.35897-1-dennisszhou@gmail.com/ [3] https://lore.kernel.org/lkml/20181020185612.51587-1-dennis@kernel.org/ This reverts the following commits: d459d853c2ed, b2c3fa546705, 101246ec02b5, b3b9f24f5fcc, e2b0989954ae, f0fcb3ec89f3, c839e7a03f92, bdc2491708c4, 74b7c02a9bc1, 5bf9a1f3b4ef, a7b39b4e961c, 07b05bcc3213, 49f4c2dc2b50, 27e6fa996c53 Signed-off-by: Dennis Zhou <dennis@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block')
-rw-r--r--block/bfq-cgroup.c4
-rw-r--r--block/bfq-iosched.c2
-rw-r--r--block/bio.c174
-rw-r--r--block/blk-cgroup.c123
-rw-r--r--block/blk-core.c1
-rw-r--r--block/blk-iolatency.c26
-rw-r--r--block/blk-throttle.c13
-rw-r--r--block/bounce.c4
-rw-r--r--block/cfq-iosched.c4
9 files changed, 127 insertions, 224 deletions
diff --git a/block/bfq-cgroup.c b/block/bfq-cgroup.c
index d9a7916ff0ab..9fe5952d117d 100644
--- a/block/bfq-cgroup.c
+++ b/block/bfq-cgroup.c
@@ -642,7 +642,7 @@ void bfq_bic_update_cgroup(struct bfq_io_cq *bic, struct bio *bio)
uint64_t serial_nr;
rcu_read_lock();
- serial_nr = __bio_blkcg(bio)->css.serial_nr;
+ serial_nr = bio_blkcg(bio)->css.serial_nr;
/*
* Check whether blkcg has changed. The condition may trigger
@@ -651,7 +651,7 @@ void bfq_bic_update_cgroup(struct bfq_io_cq *bic, struct bio *bio)
if (unlikely(!bfqd) || likely(bic->blkcg_serial_nr == serial_nr))
goto out;
- bfqg = __bfq_bic_change_cgroup(bfqd, bic, __bio_blkcg(bio));
+ bfqg = __bfq_bic_change_cgroup(bfqd, bic, bio_blkcg(bio));
/*
* Update blkg_path for bfq_log_* functions. We cache this
* path, and update it here, for the following
diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c
index 6075100f03a5..3a27d31fcda6 100644
--- a/block/bfq-iosched.c
+++ b/block/bfq-iosched.c
@@ -4384,7 +4384,7 @@ static struct bfq_queue *bfq_get_queue(struct bfq_data *bfqd,
rcu_read_lock();
- bfqg = bfq_find_set_group(bfqd, __bio_blkcg(bio));
+ bfqg = bfq_find_set_group(bfqd, bio_blkcg(bio));
if (!bfqg) {
bfqq = &bfqd->oom_bfqq;
goto out;
diff --git a/block/bio.c b/block/bio.c
index bbfeb4ee2892..4a5a036268fb 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -609,9 +609,7 @@ void __bio_clone_fast(struct bio *bio, struct bio *bio_src)
bio->bi_iter = bio_src->bi_iter;
bio->bi_io_vec = bio_src->bi_io_vec;
- bio_clone_blkg_association(bio, bio_src);
-
- blkcg_bio_issue_init(bio);
+ bio_clone_blkcg_association(bio, bio_src);
}
EXPORT_SYMBOL(__bio_clone_fast);
@@ -1956,151 +1954,69 @@ EXPORT_SYMBOL(bioset_init_from_src);
#ifdef CONFIG_BLK_CGROUP
-/**
- * bio_associate_blkg - associate a bio with the a blkg
- * @bio: target bio
- * @blkg: the blkg to associate
- *
- * This tries to associate @bio with the specified blkg. Association failure
- * is handled by walking up the blkg tree. Therefore, the blkg associated can
- * be anything between @blkg and the root_blkg. This situation only happens
- * when a cgroup is dying and then the remaining bios will spill to the closest
- * alive blkg.
- *
- * A reference will be taken on the @blkg and will be released when @bio is
- * freed.
- */
-int bio_associate_blkg(struct bio *bio, struct blkcg_gq *blkg)
-{
- if (unlikely(bio->bi_blkg))
- return -EBUSY;
- bio->bi_blkg = blkg_tryget_closest(blkg);
- return 0;
-}
-
-/**
- * __bio_associate_blkg_from_css - internal blkg association function
- *
- * This in the core association function that all association paths rely on.
- * A blkg reference is taken which is released upon freeing of the bio.
- */
-static int __bio_associate_blkg_from_css(struct bio *bio,
- struct cgroup_subsys_state *css)
-{
- struct request_queue *q = bio->bi_disk->queue;
- struct blkcg_gq *blkg;
- int ret;
-
- rcu_read_lock();
-
- if (!css || !css->parent)
- blkg = q->root_blkg;
- else
- blkg = blkg_lookup_create(css_to_blkcg(css), q);
-
- ret = bio_associate_blkg(bio, blkg);
-
- rcu_read_unlock();
- return ret;
-}
-
-/**
- * bio_associate_blkg_from_css - associate a bio with a specified css
- * @bio: target bio
- * @css: target css
- *
- * Associate @bio with the blkg found by combining the css's blkg and the
- * request_queue of the @bio. This falls back to the queue's root_blkg if
- * the association fails with the css.
- */
-int bio_associate_blkg_from_css(struct bio *bio,
- struct cgroup_subsys_state *css)
-{
- if (unlikely(bio->bi_blkg))
- return -EBUSY;
- return __bio_associate_blkg_from_css(bio, css);
-}
-EXPORT_SYMBOL_GPL(bio_associate_blkg_from_css);
-
#ifdef CONFIG_MEMCG
/**
- * bio_associate_blkg_from_page - associate a bio with the page's blkg
+ * bio_associate_blkcg_from_page - associate a bio with the page's blkcg
* @bio: target bio
* @page: the page to lookup the blkcg from
*
- * Associate @bio with the blkg from @page's owning memcg and the respective
- * request_queue. If cgroup_e_css returns NULL, fall back to the queue's
- * root_blkg.
- *
- * Note: this must be called after bio has an associated device.
+ * Associate @bio with the blkcg from @page's owning memcg. This works like
+ * every other associate function wrt references.
*/
-int bio_associate_blkg_from_page(struct bio *bio, struct page *page)
+int bio_associate_blkcg_from_page(struct bio *bio, struct page *page)
{
- struct cgroup_subsys_state *css;
- int ret;
+ struct cgroup_subsys_state *blkcg_css;
- if (unlikely(bio->bi_blkg))
+ if (unlikely(bio->bi_css))
return -EBUSY;
if (!page->mem_cgroup)
return 0;
-
- rcu_read_lock();
-
- css = cgroup_e_css(page->mem_cgroup->css.cgroup, &io_cgrp_subsys);
-
- ret = __bio_associate_blkg_from_css(bio, css);
-
- rcu_read_unlock();
- return ret;
+ blkcg_css = cgroup_get_e_css(page->mem_cgroup->css.cgroup,
+ &io_cgrp_subsys);
+ bio->bi_css = blkcg_css;
+ return 0;
}
#endif /* CONFIG_MEMCG */
/**
- * bio_associate_create_blkg - associate a bio with a blkg from q
- * @q: request_queue where bio is going
+ * bio_associate_blkcg - associate a bio with the specified blkcg
* @bio: target bio
+ * @blkcg_css: css of the blkcg to associate
+ *
+ * Associate @bio with the blkcg specified by @blkcg_css. Block layer will
+ * treat @bio as if it were issued by a task which belongs to the blkcg.
*
- * Associate @bio with the blkg found from the bio's css and the request_queue.
- * If one is not found, bio_lookup_blkg creates the blkg. This falls back to
- * the queue's root_blkg if association fails.
+ * This function takes an extra reference of @blkcg_css which will be put
+ * when @bio is released. The caller must own @bio and is responsible for
+ * synchronizing calls to this function.
*/
-int bio_associate_create_blkg(struct request_queue *q, struct bio *bio)
+int bio_associate_blkcg(struct bio *bio, struct cgroup_subsys_state *blkcg_css)
{
- struct cgroup_subsys_state *css;
- int ret = 0;
-
- /* someone has already associated this bio with a blkg */
- if (bio->bi_blkg)
- return ret;
-
- rcu_read_lock();
-
- css = blkcg_css();
-
- ret = __bio_associate_blkg_from_css(bio, css);
-
- rcu_read_unlock();
- return ret;
+ if (unlikely(bio->bi_css))
+ return -EBUSY;
+ css_get(blkcg_css);
+ bio->bi_css = blkcg_css;
+ return 0;
}
+EXPORT_SYMBOL_GPL(bio_associate_blkcg);
/**
- * bio_reassociate_blkg - reassociate a bio with a blkg from q
- * @q: request_queue where bio is going
+ * bio_associate_blkg - associate a bio with the specified blkg
* @bio: target bio
+ * @blkg: the blkg to associate
*
- * When submitting a bio, multiple recursive calls to make_request() may occur.
- * This causes the initial associate done in blkcg_bio_issue_check() to be
- * incorrect and reference the prior request_queue. This performs reassociation
- * when this situation happens.
+ * Associate @bio with the blkg specified by @blkg. This is the queue specific
+ * blkcg information associated with the @bio, a reference will be taken on the
+ * @blkg and will be freed when the bio is freed.
*/
-int bio_reassociate_blkg(struct request_queue *q, struct bio *bio)
+int bio_associate_blkg(struct bio *bio, struct blkcg_gq *blkg)
{
- if (bio->bi_blkg) {
- blkg_put(bio->bi_blkg);
- bio->bi_blkg = NULL;
- }
-
- return bio_associate_create_blkg(q, bio);
+ if (unlikely(bio->bi_blkg))
+ return -EBUSY;
+ if (!blkg_try_get(blkg))
+ return -ENODEV;
+ bio->bi_blkg = blkg;
+ return 0;
}
/**
@@ -2113,6 +2029,10 @@ void bio_disassociate_task(struct bio *bio)
put_io_context(bio->bi_ioc);
bio->bi_ioc = NULL;
}
+ if (bio->bi_css) {
+ css_put(bio->bi_css);
+ bio->bi_css = NULL;
+ }
if (bio->bi_blkg) {
blkg_put(bio->bi_blkg);
bio->bi_blkg = NULL;
@@ -2120,16 +2040,16 @@ void bio_disassociate_task(struct bio *bio)
}
/**
- * bio_clone_blkg_association - clone blkg association from src to dst bio
+ * bio_clone_blkcg_association - clone blkcg association from src to dst bio
* @dst: destination bio
* @src: source bio
*/
-void bio_clone_blkg_association(struct bio *dst, struct bio *src)
+void bio_clone_blkcg_association(struct bio *dst, struct bio *src)
{
- if (src->bi_blkg)
- bio_associate_blkg(dst, src->bi_blkg);
+ if (src->bi_css)
+ WARN_ON(bio_associate_blkcg(dst, src->bi_css));
}
-EXPORT_SYMBOL_GPL(bio_clone_blkg_association);
+EXPORT_SYMBOL_GPL(bio_clone_blkcg_association);
#endif /* CONFIG_BLK_CGROUP */
static void __init biovec_init_slabs(void)
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index 992da5592c6e..c630e02836a8 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -84,37 +84,6 @@ static void blkg_free(struct blkcg_gq *blkg)
kfree(blkg);
}
-static void __blkg_release(struct rcu_head *rcu)
-{
- struct blkcg_gq *blkg = container_of(rcu, struct blkcg_gq, rcu_head);
-
- percpu_ref_exit(&blkg->refcnt);
-
- /* release the blkcg and parent blkg refs this blkg has been holding */
- css_put(&blkg->blkcg->css);
- if (blkg->parent)
- blkg_put(blkg->parent);
-
- wb_congested_put(blkg->wb_congested);
-
- blkg_free(blkg);
-}
-
-/*
- * A group is RCU protected, but having an rcu lock does not mean that one
- * can access all the fields of blkg and assume these are valid. For
- * example, don't try to follow throtl_data and request queue links.
- *
- * Having a reference to blkg under an rcu allows accesses to only values
- * local to groups like group stats and group rate limits.
- */
-static void blkg_release(struct percpu_ref *ref)
-{
- struct blkcg_gq *blkg = container_of(ref, struct blkcg_gq, refcnt);
-
- call_rcu(&blkg->rcu_head, __blkg_release);
-}
-
/**
* blkg_alloc - allocate a blkg
* @blkcg: block cgroup the new blkg is associated with
@@ -141,6 +110,7 @@ static struct blkcg_gq *blkg_alloc(struct blkcg *blkcg, struct request_queue *q,
blkg->q = q;
INIT_LIST_HEAD(&blkg->q_node);
blkg->blkcg = blkcg;
+ atomic_set(&blkg->refcnt, 1);
/* root blkg uses @q->root_rl, init rl only for !root blkgs */
if (blkcg != &blkcg_root) {
@@ -247,11 +217,6 @@ static struct blkcg_gq *blkg_create(struct blkcg *blkcg,
blkg_get(blkg->parent);
}
- ret = percpu_ref_init(&blkg->refcnt, blkg_release, 0,
- GFP_NOWAIT | __GFP_NOWARN);
- if (ret)
- goto err_cancel_ref;
-
/* invoke per-policy init */
for (i = 0; i < BLKCG_MAX_POLS; i++) {
struct blkcg_policy *pol = blkcg_policy[i];
@@ -284,8 +249,6 @@ static struct blkcg_gq *blkg_create(struct blkcg *blkcg,
blkg_put(blkg);
return ERR_PTR(ret);
-err_cancel_ref:
- percpu_ref_exit(&blkg->refcnt);
err_put_congested:
wb_congested_put(wb_congested);
err_put_css:
@@ -296,7 +259,7 @@ err_free_blkg:
}
/**
- * __blkg_lookup_create - lookup blkg, try to create one if not there
+ * blkg_lookup_create - lookup blkg, try to create one if not there
* @blkcg: blkcg of interest
* @q: request_queue of interest
*
@@ -305,11 +268,12 @@ err_free_blkg:
* that all non-root blkg's have access to the parent blkg. This function
* should be called under RCU read lock and @q->queue_lock.
*
- * Returns the blkg or the closest blkg if blkg_create fails as it walks
- * down from root.
+ * Returns pointer to the looked up or created blkg on success, ERR_PTR()
+ * value on error. If @q is dead, returns ERR_PTR(-EINVAL). If @q is not
+ * dead and bypassing, returns ERR_PTR(-EBUSY).
*/
-struct blkcg_gq *__blkg_lookup_create(struct blkcg *blkcg,
- struct request_queue *q)
+struct blkcg_gq *blkg_lookup_create(struct blkcg *blkcg,
+ struct request_queue *q)
{
struct blkcg_gq *blkg;
@@ -321,7 +285,7 @@ struct blkcg_gq *__blkg_lookup_create(struct blkcg *blkcg,
* we shouldn't allow anything to go through for a bypassing queue.
*/
if (unlikely(blk_queue_bypass(q)))
- return q->root_blkg;
+ return ERR_PTR(blk_queue_dying(q) ? -ENODEV : -EBUSY);
blkg = __blkg_lookup(blkcg, q, true);
if (blkg)
@@ -329,58 +293,23 @@ struct blkcg_gq *__blkg_lookup_create(struct blkcg *blkcg,
/*
* Create blkgs walking down from blkcg_root to @blkcg, so that all
- * non-root blkgs have access to their parents. Returns the closest
- * blkg to the intended blkg should blkg_create() fail.
+ * non-root blkgs have access to their parents.
*/
while (true) {
struct blkcg *pos = blkcg;
struct blkcg *parent = blkcg_parent(blkcg);
- struct blkcg_gq *ret_blkg = q->root_blkg;
-
- while (parent) {
- blkg = __blkg_lookup(parent, q, false);
- if (blkg) {
- /* remember closest blkg */
- ret_blkg = blkg;
- break;
- }
+
+ while (parent && !__blkg_lookup(parent, q, false)) {
pos = parent;
parent = blkcg_parent(parent);
}
blkg = blkg_create(pos, q, NULL);
- if (IS_ERR(blkg))
- return ret_blkg;
- if (pos == blkcg)
+ if (pos == blkcg || IS_ERR(blkg))
return blkg;
}
}
-/**
- * blkg_lookup_create - find or create a blkg
- * @blkcg: target block cgroup
- * @q: target request_queue
- *
- * This looks up or creates the blkg representing the unique pair
- * of the blkcg and the request_queue.
- */
-struct blkcg_gq *blkg_lookup_create(struct blkcg *blkcg,
- struct request_queue *q)
-{
- struct blkcg_gq *blkg = blkg_lookup(blkcg, q);
- unsigned long flags;
-
- if (unlikely(!blkg)) {
- spin_lock_irqsave(q->queue_lock, flags);
-
- blkg = __blkg_lookup_create(blkcg, q);
-
- spin_unlock_irqrestore(q->queue_lock, flags);
- }
-
- return blkg;
-}
-
static void blkg_destroy(struct blkcg_gq *blkg)
{
struct blkcg *blkcg = blkg->blkcg;
@@ -424,7 +353,7 @@ static void blkg_destroy(struct blkcg_gq *blkg)
* Put the reference taken at the time of creation so that when all
* queues are gone, group can be destroyed.
*/
- percpu_ref_kill(&blkg->refcnt);
+ blkg_put(blkg);
}
/**
@@ -452,6 +381,29 @@ static void blkg_destroy_all(struct request_queue *q)
}
/*
+ * A group is RCU protected, but having an rcu lock does not mean that one
+ * can access all the fields of blkg and assume these are valid. For
+ * example, don't try to follow throtl_data and request queue links.
+ *
+ * Having a reference to blkg under an rcu allows accesses to only values
+ * local to groups like group stats and group rate limits.
+ */
+void __blkg_release_rcu(struct rcu_head *rcu_head)
+{
+ struct blkcg_gq *blkg = container_of(rcu_head, struct blkcg_gq, rcu_head);
+
+ /* release the blkcg and parent blkg refs this blkg has been holding */
+ css_put(&blkg->blkcg->css);
+ if (blkg->parent)
+ blkg_put(blkg->parent);
+
+ wb_congested_put(blkg->wb_congested);
+
+ blkg_free(blkg);
+}
+EXPORT_SYMBOL_GPL(__blkg_release_rcu);
+
+/*
* The next function used by blk_queue_for_each_rl(). It's a bit tricky
* because the root blkg uses @q->root_rl instead of its own rl.
*/
@@ -1796,7 +1748,8 @@ void blkcg_maybe_throttle_current(void)
blkg = blkg_lookup(blkcg, q);
if (!blkg)
goto out;
- if (!blkg_tryget(blkg))
+ blkg = blkg_try_get(blkg);
+ if (!blkg)
goto out;
rcu_read_unlock();
diff --git a/block/blk-core.c b/block/blk-core.c
index 26a5dac80ed9..ce12515f9b9b 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -2435,7 +2435,6 @@ blk_qc_t generic_make_request(struct bio *bio)
if (q)
blk_queue_exit(q);
q = bio->bi_disk->queue;
- bio_reassociate_blkg(q, bio);
flags = 0;
if (bio->bi_opf & REQ_NOWAIT)
flags = BLK_MQ_REQ_NOWAIT;
diff --git a/block/blk-iolatency.c b/block/blk-iolatency.c
index 35c48d7b8f78..bb240a0c1309 100644
--- a/block/blk-iolatency.c
+++ b/block/blk-iolatency.c
@@ -480,12 +480,34 @@ static void blkcg_iolatency_throttle(struct rq_qos *rqos, struct bio *bio,
spinlock_t *lock)
{
struct blk_iolatency *blkiolat = BLKIOLATENCY(rqos);
- struct blkcg_gq *blkg = bio->bi_blkg;
+ struct blkcg *blkcg;
+ struct blkcg_gq *blkg;
+ struct request_queue *q = rqos->q;
bool issue_as_root = bio_issue_as_root_blkg(bio);
if (!blk_iolatency_enabled(blkiolat))
return;
+ rcu_read_lock();
+ blkcg = bio_blkcg(bio);
+ bio_associate_blkcg(bio, &blkcg->css);
+ blkg = blkg_lookup(blkcg, q);
+ if (unlikely(!blkg)) {
+ if (!lock)
+ spin_lock_irq(q->queue_lock);
+ blkg = blkg_lookup_create(blkcg, q);
+ if (IS_ERR(blkg))
+ blkg = NULL;
+ if (!lock)
+ spin_unlock_irq(q->queue_lock);
+ }
+ if (!blkg)
+ goto out;
+
+ bio_issue_init(&bio->bi_issue, bio_sectors(bio));
+ bio_associate_blkg(bio, blkg);
+out:
+ rcu_read_unlock();
while (blkg && blkg->parent) {
struct iolatency_grp *iolat = blkg_to_lat(blkg);
if (!iolat) {
@@ -706,7 +728,7 @@ static void blkiolatency_timer_fn(struct timer_list *t)
* We could be exiting, don't access the pd unless we have a
* ref on the blkg.
*/
- if (!blkg_tryget(blkg))
+ if (!blkg_try_get(blkg))
continue;
iolat = blkg_to_lat(blkg);
diff --git a/block/blk-throttle.c b/block/blk-throttle.c
index 4bda70e8db48..db1a3a2ae006 100644
--- a/block/blk-throttle.c
+++ b/block/blk-throttle.c
@@ -2115,11 +2115,21 @@ static inline void throtl_update_latency_buckets(struct throtl_data *td)
}
#endif
+static void blk_throtl_assoc_bio(struct throtl_grp *tg, struct bio *bio)
+{
+#ifdef CONFIG_BLK_DEV_THROTTLING_LOW
+ /* fallback to root_blkg if we fail to get a blkg ref */
+ if (bio->bi_css && (bio_associate_blkg(bio, tg_to_blkg(tg)) == -ENODEV))
+ bio_associate_blkg(bio, bio->bi_disk->queue->root_blkg);
+ bio_issue_init(&bio->bi_issue, bio_sectors(bio));
+#endif
+}
+
bool blk_throtl_bio(struct request_queue *q, struct blkcg_gq *blkg,
struct bio *bio)
{
struct throtl_qnode *qn = NULL;
- struct throtl_grp *tg = blkg_to_tg(blkg);
+ struct throtl_grp *tg = blkg_to_tg(blkg ?: q->root_blkg);
struct throtl_service_queue *sq;
bool rw = bio_data_dir(bio);
bool throttled = false;
@@ -2138,6 +2148,7 @@ bool blk_throtl_bio(struct request_queue *q, struct blkcg_gq *blkg,
if (unlikely(blk_queue_bypass(q)))
goto out_unlock;
+ blk_throtl_assoc_bio(tg, bio);
blk_throtl_update_idletime(tg);
sq = &tg->service_queue;
diff --git a/block/bounce.c b/block/bounce.c
index ec0d99995f5f..418677dcec60 100644
--- a/block/bounce.c
+++ b/block/bounce.c
@@ -276,9 +276,7 @@ static struct bio *bounce_clone_bio(struct bio *bio_src, gfp_t gfp_mask,
}
}
- bio_clone_blkg_association(bio, bio_src);
-
- blkcg_bio_issue_init(bio);
+ bio_clone_blkcg_association(bio, bio_src);
return bio;
}
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index 6a3d87dd3c1a..ed41aa978c4a 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -3759,7 +3759,7 @@ static void check_blkcg_changed(struct cfq_io_cq *cic, struct bio *bio)
uint64_t serial_nr;
rcu_read_lock();
- serial_nr = __bio_blkcg(bio)->css.serial_nr;
+ serial_nr = bio_blkcg(bio)->css.serial_nr;
rcu_read_unlock();
/*
@@ -3824,7 +3824,7 @@ cfq_get_queue(struct cfq_data *cfqd, bool is_sync, struct cfq_io_cq *cic,
struct cfq_group *cfqg;
rcu_read_lock();
- cfqg = cfq_lookup_cfqg(cfqd, __bio_blkcg(bio));
+ cfqg = cfq_lookup_cfqg(cfqd, bio_blkcg(bio));
if (!cfqg) {
cfqq = &cfqd->oom_cfqq;
goto out;