diff options
| -rw-r--r-- | block/blk-cgroup.c | 38 | ||||
| -rw-r--r-- | include/linux/blk-cgroup.h | 49 |
2 files changed, 47 insertions, 40 deletions
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index 2b4354b..52e637e 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -131,26 +131,11 @@ err_free: return NULL; } -/** - * __blkg_lookup - internal version of blkg_lookup() - * @blkcg: blkcg of interest - * @q: request_queue of interest - * @update_hint: whether to update lookup hint with the result or not - * - * This is internal version and shouldn't be used by policy - * implementations. Looks up blkgs for the @blkcg - @q pair regardless of - * @q's bypass state. If @update_hint is %true, the caller should be - * holding @q->queue_lock and lookup hint is updated on success. - */ -struct blkcg_gq *__blkg_lookup(struct blkcg *blkcg, struct request_queue *q, - bool update_hint) +struct blkcg_gq *blkg_lookup_slowpath(struct blkcg *blkcg, + struct request_queue *q, bool update_hint) { struct blkcg_gq *blkg; - blkg = rcu_dereference(blkcg->blkg_hint); - if (blkg && blkg->q == q) - return blkg; - /* * Hint didn't match. Look up from the radix tree. Note that the * hint can only be updated under queue_lock as otherwise @blkg @@ -169,25 +154,6 @@ struct blkcg_gq *__blkg_lookup(struct blkcg *blkcg, struct request_queue *q, return NULL; } -/** - * blkg_lookup - lookup blkg for the specified blkcg - q pair - * @blkcg: blkcg of interest - * @q: request_queue of interest - * - * Lookup blkg for the @blkcg - @q pair. This function should be called - * under RCU read lock and is guaranteed to return %NULL if @q is bypassing - * - see blk_queue_bypass_start() for details. - */ -struct blkcg_gq *blkg_lookup(struct blkcg *blkcg, struct request_queue *q) -{ - WARN_ON_ONCE(!rcu_read_lock_held()); - - if (unlikely(blk_queue_bypass(q))) - return NULL; - return __blkg_lookup(blkcg, q, false); -} -EXPORT_SYMBOL_GPL(blkg_lookup); - /* * If @new_blkg is %NULL, this function tries to allocate a new one as * necessary using %GFP_NOWAIT. @new_blkg is always consumed on return. diff --git a/include/linux/blk-cgroup.h b/include/linux/blk-cgroup.h index 15f2382..d5b54aa 100644 --- a/include/linux/blk-cgroup.h +++ b/include/linux/blk-cgroup.h @@ -155,7 +155,8 @@ struct blkcg_policy { extern struct blkcg blkcg_root; extern struct cgroup_subsys_state * const blkcg_root_css; -struct blkcg_gq *blkg_lookup(struct blkcg *blkcg, struct request_queue *q); +struct blkcg_gq *blkg_lookup_slowpath(struct blkcg *blkcg, + struct request_queue *q, bool update_hint); struct blkcg_gq *blkg_lookup_create(struct blkcg *blkcg, struct request_queue *q); int blkcg_init_queue(struct request_queue *q); @@ -232,6 +233,49 @@ static inline struct blkcg *blkcg_parent(struct blkcg *blkcg) } /** + * __blkg_lookup - internal version of blkg_lookup() + * @blkcg: blkcg of interest + * @q: request_queue of interest + * @update_hint: whether to update lookup hint with the result or not + * + * This is internal version and shouldn't be used by policy + * implementations. Looks up blkgs for the @blkcg - @q pair regardless of + * @q's bypass state. If @update_hint is %true, the caller should be + * holding @q->queue_lock and lookup hint is updated on success. + */ +static inline struct blkcg_gq *__blkg_lookup(struct blkcg *blkcg, + struct request_queue *q, + bool update_hint) +{ + struct blkcg_gq *blkg; + + blkg = rcu_dereference(blkcg->blkg_hint); + if (blkg && blkg->q == q) + return blkg; + + return blkg_lookup_slowpath(blkcg, q, update_hint); +} + +/** + * blkg_lookup - lookup blkg for the specified blkcg - q pair + * @blkcg: blkcg of interest + * @q: request_queue of interest + * + * Lookup blkg for the @blkcg - @q pair. This function should be called + * under RCU read lock and is guaranteed to return %NULL if @q is bypassing + * - see blk_queue_bypass_start() for details. + */ +static inline struct blkcg_gq *blkg_lookup(struct blkcg *blkcg, + struct request_queue *q) +{ + WARN_ON_ONCE(!rcu_read_lock_held()); + + if (unlikely(blk_queue_bypass(q))) + return NULL; + return __blkg_lookup(blkcg, q, false); +} + +/** * blkg_to_pdata - get policy private data * @blkg: blkg of interest * @pol: policy of interest @@ -313,9 +357,6 @@ static inline void blkg_put(struct blkcg_gq *blkg) call_rcu(&blkg->rcu_head, __blkg_release_rcu); } -struct blkcg_gq *__blkg_lookup(struct blkcg *blkcg, struct request_queue *q, - bool update_hint); - /** * blkg_for_each_descendant_pre - pre-order walk of a blkg's descendants * @d_blkg: loop cursor pointing to the current descendant |
