diff options
Diffstat (limited to 'block/blk-cgroup.h')
-rw-r--r-- | block/blk-cgroup.h | 647 |
1 files changed, 334 insertions, 313 deletions
diff --git a/block/blk-cgroup.h b/block/blk-cgroup.h index 6f3ace7e792..8ac457ce778 100644 --- a/block/blk-cgroup.h +++ b/block/blk-cgroup.h @@ -15,350 +15,371 @@ #include <linux/cgroup.h> #include <linux/u64_stats_sync.h> - -enum blkio_policy_id { - BLKIO_POLICY_PROP = 0, /* Proportional Bandwidth division */ - BLKIO_POLICY_THROTL, /* Throttling */ -}; +#include <linux/seq_file.h> +#include <linux/radix-tree.h> /* Max limits for throttle policy */ #define THROTL_IOPS_MAX UINT_MAX -#if defined(CONFIG_BLK_CGROUP) || defined(CONFIG_BLK_CGROUP_MODULE) - -#ifndef CONFIG_BLK_CGROUP -/* When blk-cgroup is a module, its subsys_id isn't a compile-time constant */ -extern struct cgroup_subsys blkio_subsys; -#define blkio_subsys_id blkio_subsys.subsys_id -#endif - -enum stat_type { - /* Total time spent (in ns) between request dispatch to the driver and - * request completion for IOs doen by this cgroup. This may not be - * accurate when NCQ is turned on. */ - BLKIO_STAT_SERVICE_TIME = 0, - /* Total time spent waiting in scheduler queue in ns */ - BLKIO_STAT_WAIT_TIME, - /* Number of IOs queued up */ - BLKIO_STAT_QUEUED, - /* All the single valued stats go below this */ - BLKIO_STAT_TIME, -#ifdef CONFIG_DEBUG_BLK_CGROUP - /* Time not charged to this cgroup */ - BLKIO_STAT_UNACCOUNTED_TIME, - BLKIO_STAT_AVG_QUEUE_SIZE, - BLKIO_STAT_IDLE_TIME, - BLKIO_STAT_EMPTY_TIME, - BLKIO_STAT_GROUP_WAIT_TIME, - BLKIO_STAT_DEQUEUE -#endif -}; +/* CFQ specific, out here for blkcg->cfq_weight */ +#define CFQ_WEIGHT_MIN 10 +#define CFQ_WEIGHT_MAX 1000 +#define CFQ_WEIGHT_DEFAULT 500 -/* Per cpu stats */ -enum stat_type_cpu { - BLKIO_STAT_CPU_SECTORS, - /* Total bytes transferred */ - BLKIO_STAT_CPU_SERVICE_BYTES, - /* Total IOs serviced, post merge */ - BLKIO_STAT_CPU_SERVICED, - /* Number of IOs merged */ - BLKIO_STAT_CPU_MERGED, - BLKIO_STAT_CPU_NR -}; +#ifdef CONFIG_BLK_CGROUP -enum stat_sub_type { - BLKIO_STAT_READ = 0, - BLKIO_STAT_WRITE, - BLKIO_STAT_SYNC, - BLKIO_STAT_ASYNC, - BLKIO_STAT_TOTAL -}; +enum blkg_rwstat_type { + BLKG_RWSTAT_READ, + BLKG_RWSTAT_WRITE, + BLKG_RWSTAT_SYNC, + BLKG_RWSTAT_ASYNC, -/* blkg state flags */ -enum blkg_state_flags { - BLKG_waiting = 0, - BLKG_idling, - BLKG_empty, + BLKG_RWSTAT_NR, + BLKG_RWSTAT_TOTAL = BLKG_RWSTAT_NR, }; -/* cgroup files owned by proportional weight policy */ -enum blkcg_file_name_prop { - BLKIO_PROP_weight = 1, - BLKIO_PROP_weight_device, - BLKIO_PROP_io_service_bytes, - BLKIO_PROP_io_serviced, - BLKIO_PROP_time, - BLKIO_PROP_sectors, - BLKIO_PROP_unaccounted_time, - BLKIO_PROP_io_service_time, - BLKIO_PROP_io_wait_time, - BLKIO_PROP_io_merged, - BLKIO_PROP_io_queued, - BLKIO_PROP_avg_queue_size, - BLKIO_PROP_group_wait_time, - BLKIO_PROP_idle_time, - BLKIO_PROP_empty_time, - BLKIO_PROP_dequeue, -}; +struct blkcg_gq; -/* cgroup files owned by throttle policy */ -enum blkcg_file_name_throtl { - BLKIO_THROTL_read_bps_device, - BLKIO_THROTL_write_bps_device, - BLKIO_THROTL_read_iops_device, - BLKIO_THROTL_write_iops_device, - BLKIO_THROTL_io_service_bytes, - BLKIO_THROTL_io_serviced, -}; +struct blkcg { + struct cgroup_subsys_state css; + spinlock_t lock; -struct blkio_cgroup { - struct cgroup_subsys_state css; - unsigned int weight; - spinlock_t lock; - struct hlist_head blkg_list; - struct list_head policy_list; /* list of blkio_policy_node */ -}; + struct radix_tree_root blkg_tree; + struct blkcg_gq *blkg_hint; + struct hlist_head blkg_list; + + /* for policies to test whether associated blkcg has changed */ + uint64_t id; -struct blkio_group_stats { - /* total disk time and nr sectors dispatched by this group */ - uint64_t time; - uint64_t stat_arr[BLKIO_STAT_QUEUED + 1][BLKIO_STAT_TOTAL]; -#ifdef CONFIG_DEBUG_BLK_CGROUP - /* Time not charged to this cgroup */ - uint64_t unaccounted_time; - - /* Sum of number of IOs queued across all samples */ - uint64_t avg_queue_size_sum; - /* Count of samples taken for average */ - uint64_t avg_queue_size_samples; - /* How many times this group has been removed from service tree */ - unsigned long dequeue; - - /* Total time spent waiting for it to be assigned a timeslice. */ - uint64_t group_wait_time; - uint64_t start_group_wait_time; - - /* Time spent idling for this blkio_group */ - uint64_t idle_time; - uint64_t start_idle_time; - /* - * Total time when we have requests queued and do not contain the - * current active queue. - */ - uint64_t empty_time; - uint64_t start_empty_time; - uint16_t flags; -#endif + /* TODO: per-policy storage in blkcg */ + unsigned int cfq_weight; /* belongs to cfq */ }; -/* Per cpu blkio group stats */ -struct blkio_group_stats_cpu { - uint64_t sectors; - uint64_t stat_arr_cpu[BLKIO_STAT_CPU_NR][BLKIO_STAT_TOTAL]; - struct u64_stats_sync syncp; +struct blkg_stat { + struct u64_stats_sync syncp; + uint64_t cnt; }; -struct blkio_group { - /* An rcu protected unique identifier for the group */ - void *key; - struct hlist_node blkcg_node; - unsigned short blkcg_id; - /* Store cgroup path */ - char path[128]; - /* The device MKDEV(major, minor), this group has been created for */ - dev_t dev; - /* policy which owns this blk group */ - enum blkio_policy_id plid; - - /* Need to serialize the stats in the case of reset/update */ - spinlock_t stats_lock; - struct blkio_group_stats stats; - /* Per cpu stats pointer */ - struct blkio_group_stats_cpu __percpu *stats_cpu; +struct blkg_rwstat { + struct u64_stats_sync syncp; + uint64_t cnt[BLKG_RWSTAT_NR]; }; -struct blkio_policy_node { - struct list_head node; - dev_t dev; - /* This node belongs to max bw policy or porportional weight policy */ - enum blkio_policy_id plid; - /* cgroup file to which this rule belongs to */ - int fileid; - - union { - unsigned int weight; - /* - * Rate read/write in terms of bytes per second - * Whether this rate represents read or write is determined - * by file type "fileid". - */ - u64 bps; - unsigned int iops; - } val; +/* + * A blkcg_gq (blkg) is association between a block cgroup (blkcg) and a + * request_queue (q). This is used by blkcg policies which need to track + * information per blkcg - q pair. + * + * There can be multiple active blkcg policies and each has its private + * data on each blkg, the size of which is determined by + * blkcg_policy->pd_size. blkcg core allocates and frees such areas + * together with blkg and invokes pd_init/exit_fn() methods. + * + * Such private data must embed struct blkg_policy_data (pd) at the + * beginning and pd_size can't be smaller than pd. + */ +struct blkg_policy_data { + /* the blkg this per-policy data belongs to */ + struct blkcg_gq *blkg; + + /* used during policy activation */ + struct list_head alloc_node; }; -extern unsigned int blkcg_get_weight(struct blkio_cgroup *blkcg, - dev_t dev); -extern uint64_t blkcg_get_read_bps(struct blkio_cgroup *blkcg, - dev_t dev); -extern uint64_t blkcg_get_write_bps(struct blkio_cgroup *blkcg, - dev_t dev); -extern unsigned int blkcg_get_read_iops(struct blkio_cgroup *blkcg, - dev_t dev); -extern unsigned int blkcg_get_write_iops(struct blkio_cgroup *blkcg, - dev_t dev); - -typedef void (blkio_unlink_group_fn) (void *key, struct blkio_group *blkg); - -typedef void (blkio_update_group_weight_fn) (void *key, - struct blkio_group *blkg, unsigned int weight); -typedef void (blkio_update_group_read_bps_fn) (void * key, - struct blkio_group *blkg, u64 read_bps); -typedef void (blkio_update_group_write_bps_fn) (void *key, - struct blkio_group *blkg, u64 write_bps); -typedef void (blkio_update_group_read_iops_fn) (void *key, - struct blkio_group *blkg, unsigned int read_iops); -typedef void (blkio_update_group_write_iops_fn) (void *key, - struct blkio_group *blkg, unsigned int write_iops); - -struct blkio_policy_ops { - blkio_unlink_group_fn *blkio_unlink_group_fn; - blkio_update_group_weight_fn *blkio_update_group_weight_fn; - blkio_update_group_read_bps_fn *blkio_update_group_read_bps_fn; - blkio_update_group_write_bps_fn *blkio_update_group_write_bps_fn; - blkio_update_group_read_iops_fn *blkio_update_group_read_iops_fn; - blkio_update_group_write_iops_fn *blkio_update_group_write_iops_fn; +/* association between a blk cgroup and a request queue */ +struct blkcg_gq { + /* Pointer to the associated request_queue */ + struct request_queue *q; + struct list_head q_node; + struct hlist_node blkcg_node; + struct blkcg *blkcg; + /* reference count */ + int refcnt; + + struct blkg_policy_data *pd[BLKCG_MAX_POLS]; + + struct rcu_head rcu_head; }; -struct blkio_policy_type { - struct list_head list; - struct blkio_policy_ops ops; - enum blkio_policy_id plid; +typedef void (blkcg_pol_init_pd_fn)(struct blkcg_gq *blkg); +typedef void (blkcg_pol_exit_pd_fn)(struct blkcg_gq *blkg); +typedef void (blkcg_pol_reset_pd_stats_fn)(struct blkcg_gq *blkg); + +struct blkcg_policy { + int plid; + /* policy specific private data size */ + size_t pd_size; + /* cgroup files for the policy */ + struct cftype *cftypes; + + /* operations */ + blkcg_pol_init_pd_fn *pd_init_fn; + blkcg_pol_exit_pd_fn *pd_exit_fn; + blkcg_pol_reset_pd_stats_fn *pd_reset_stats_fn; }; +extern struct blkcg blkcg_root; + +struct blkcg *cgroup_to_blkcg(struct cgroup *cgroup); +struct blkcg *bio_blkcg(struct bio *bio); +struct blkcg_gq *blkg_lookup(struct blkcg *blkcg, struct request_queue *q); +struct blkcg_gq *blkg_lookup_create(struct blkcg *blkcg, + struct request_queue *q); +int blkcg_init_queue(struct request_queue *q); +void blkcg_drain_queue(struct request_queue *q); +void blkcg_exit_queue(struct request_queue *q); + /* Blkio controller policy registration */ -extern void blkio_policy_register(struct blkio_policy_type *); -extern void blkio_policy_unregister(struct blkio_policy_type *); +int blkcg_policy_register(struct blkcg_policy *pol); +void blkcg_policy_unregister(struct blkcg_policy *pol); +int blkcg_activate_policy(struct request_queue *q, + const struct blkcg_policy *pol); +void blkcg_deactivate_policy(struct request_queue *q, + const struct blkcg_policy *pol); + +void blkcg_print_blkgs(struct seq_file *sf, struct blkcg *blkcg, + u64 (*prfill)(struct seq_file *, + struct blkg_policy_data *, int), + const struct blkcg_policy *pol, int data, + bool show_total); +u64 __blkg_prfill_u64(struct seq_file *sf, struct blkg_policy_data *pd, u64 v); +u64 __blkg_prfill_rwstat(struct seq_file *sf, struct blkg_policy_data *pd, + const struct blkg_rwstat *rwstat); +u64 blkg_prfill_stat(struct seq_file *sf, struct blkg_policy_data *pd, int off); +u64 blkg_prfill_rwstat(struct seq_file *sf, struct blkg_policy_data *pd, + int off); + +struct blkg_conf_ctx { + struct gendisk *disk; + struct blkcg_gq *blkg; + u64 v; +}; + +int blkg_conf_prep(struct blkcg *blkcg, const struct blkcg_policy *pol, + const char *input, struct blkg_conf_ctx *ctx); +void blkg_conf_finish(struct blkg_conf_ctx *ctx); + + +/** + * blkg_to_pdata - get policy private data + * @blkg: blkg of interest + * @pol: policy of interest + * + * Return pointer to private data associated with the @blkg-@pol pair. + */ +static inline struct blkg_policy_data *blkg_to_pd(struct blkcg_gq *blkg, + struct blkcg_policy *pol) +{ + return blkg ? blkg->pd[pol->plid] : NULL; +} + +/** + * pdata_to_blkg - get blkg associated with policy private data + * @pd: policy private data of interest + * + * @pd is policy private data. Determine the blkg it's associated with. + */ +static inline struct blkcg_gq *pd_to_blkg(struct blkg_policy_data *pd) +{ + return pd ? pd->blkg : NULL; +} + +/** + * blkg_path - format cgroup path of blkg + * @blkg: blkg of interest + * @buf: target buffer + * @buflen: target buffer length + * + * Format the path of the cgroup of @blkg into @buf. + */ +static inline int blkg_path(struct blkcg_gq *blkg, char *buf, int buflen) +{ + int ret; + + rcu_read_lock(); + ret = cgroup_path(blkg->blkcg->css.cgroup, buf, buflen); + rcu_read_unlock(); + if (ret) + strncpy(buf, "<unavailable>", buflen); + return ret; +} -static inline char *blkg_path(struct blkio_group *blkg) +/** + * blkg_get - get a blkg reference + * @blkg: blkg to get + * + * The caller should be holding queue_lock and an existing reference. + */ +static inline void blkg_get(struct blkcg_gq *blkg) { - return blkg->path; + lockdep_assert_held(blkg->q->queue_lock); + WARN_ON_ONCE(!blkg->refcnt); + blkg->refcnt++; } -#else +void __blkg_release(struct blkcg_gq *blkg); -struct blkio_group { +/** + * blkg_put - put a blkg reference + * @blkg: blkg to put + * + * The caller should be holding queue_lock. + */ +static inline void blkg_put(struct blkcg_gq *blkg) +{ + lockdep_assert_held(blkg->q->queue_lock); + WARN_ON_ONCE(blkg->refcnt <= 0); + if (!--blkg->refcnt) + __blkg_release(blkg); +} + +/** + * blkg_stat_add - add a value to a blkg_stat + * @stat: target blkg_stat + * @val: value to add + * + * Add @val to @stat. The caller is responsible for synchronizing calls to + * this function. + */ +static inline void blkg_stat_add(struct blkg_stat *stat, uint64_t val) +{ + u64_stats_update_begin(&stat->syncp); + stat->cnt += val; + u64_stats_update_end(&stat->syncp); +} + +/** + * blkg_stat_read - read the current value of a blkg_stat + * @stat: blkg_stat to read + * + * Read the current value of @stat. This function can be called without + * synchroniztion and takes care of u64 atomicity. + */ +static inline uint64_t blkg_stat_read(struct blkg_stat *stat) +{ + unsigned int start; + uint64_t v; + + do { + start = u64_stats_fetch_begin(&stat->syncp); + v = stat->cnt; + } while (u64_stats_fetch_retry(&stat->syncp, start)); + + return v; +} + +/** + * blkg_stat_reset - reset a blkg_stat + * @stat: blkg_stat to reset + */ +static inline void blkg_stat_reset(struct blkg_stat *stat) +{ + stat->cnt = 0; +} + +/** + * blkg_rwstat_add - add a value to a blkg_rwstat + * @rwstat: target blkg_rwstat + * @rw: mask of REQ_{WRITE|SYNC} + * @val: value to add + * + * Add @val to @rwstat. The counters are chosen according to @rw. The + * caller is responsible for synchronizing calls to this function. + */ +static inline void blkg_rwstat_add(struct blkg_rwstat *rwstat, + int rw, uint64_t val) +{ + u64_stats_update_begin(&rwstat->syncp); + + if (rw & REQ_WRITE) + rwstat->cnt[BLKG_RWSTAT_WRITE] += val; + else + rwstat->cnt[BLKG_RWSTAT_READ] += val; + if (rw & REQ_SYNC) + rwstat->cnt[BLKG_RWSTAT_SYNC] += val; + else + rwstat->cnt[BLKG_RWSTAT_ASYNC] += val; + + u64_stats_update_end(&rwstat->syncp); +} + +/** + * blkg_rwstat_read - read the current values of a blkg_rwstat + * @rwstat: blkg_rwstat to read + * + * Read the current snapshot of @rwstat and return it as the return value. + * This function can be called without synchronization and takes care of + * u64 atomicity. + */ +static inline struct blkg_rwstat blkg_rwstat_read(struct blkg_rwstat *rwstat) +{ + unsigned int start; + struct blkg_rwstat tmp; + + do { + start = u64_stats_fetch_begin(&rwstat->syncp); + tmp = *rwstat; + } while (u64_stats_fetch_retry(&rwstat->syncp, start)); + + return tmp; +} + +/** + * blkg_rwstat_sum - read the total count of a blkg_rwstat + * @rwstat: blkg_rwstat to read + * + * Return the total count of @rwstat regardless of the IO direction. This + * function can be called without synchronization and takes care of u64 + * atomicity. + */ +static inline uint64_t blkg_rwstat_sum(struct blkg_rwstat *rwstat) +{ + struct blkg_rwstat tmp = blkg_rwstat_read(rwstat); + + return tmp.cnt[BLKG_RWSTAT_READ] + tmp.cnt[BLKG_RWSTAT_WRITE]; +} + +/** + * blkg_rwstat_reset - reset a blkg_rwstat + * @rwstat: blkg_rwstat to reset + */ +static inline void blkg_rwstat_reset(struct blkg_rwstat *rwstat) +{ + memset(rwstat->cnt, 0, sizeof(rwstat->cnt)); +} + +#else /* CONFIG_BLK_CGROUP */ + +struct cgroup; + +struct blkg_policy_data { }; -struct blkio_policy_type { +struct blkcg_gq { }; -static inline void blkio_policy_register(struct blkio_policy_type *blkiop) { } -static inline void blkio_policy_unregister(struct blkio_policy_type *blkiop) { } - -static inline char *blkg_path(struct blkio_group *blkg) { return NULL; } - -#endif - -#define BLKIO_WEIGHT_MIN 10 -#define BLKIO_WEIGHT_MAX 1000 -#define BLKIO_WEIGHT_DEFAULT 500 - -#ifdef CONFIG_DEBUG_BLK_CGROUP -void blkiocg_update_avg_queue_size_stats(struct blkio_group *blkg); -void blkiocg_update_dequeue_stats(struct blkio_group *blkg, - unsigned long dequeue); -void blkiocg_update_set_idle_time_stats(struct blkio_group *blkg); -void blkiocg_update_idle_time_stats(struct blkio_group *blkg); -void blkiocg_set_start_empty_time(struct blkio_group *blkg); - -#define BLKG_FLAG_FNS(name) \ -static inline void blkio_mark_blkg_##name( \ - struct blkio_group_stats *stats) \ -{ \ - stats->flags |= (1 << BLKG_##name); \ -} \ -static inline void blkio_clear_blkg_##name( \ - struct blkio_group_stats *stats) \ -{ \ - stats->flags &= ~(1 << BLKG_##name); \ -} \ -static inline int blkio_blkg_##name(struct blkio_group_stats *stats) \ -{ \ - return (stats->flags & (1 << BLKG_##name)) != 0; \ -} \ - -BLKG_FLAG_FNS(waiting) -BLKG_FLAG_FNS(idling) -BLKG_FLAG_FNS(empty) -#undef BLKG_FLAG_FNS -#else -static inline void blkiocg_update_avg_queue_size_stats( - struct blkio_group *blkg) {} -static inline void blkiocg_update_dequeue_stats(struct blkio_group *blkg, - unsigned long dequeue) {} -static inline void blkiocg_update_set_idle_time_stats(struct blkio_group *blkg) -{} -static inline void blkiocg_update_idle_time_stats(struct blkio_group *blkg) {} -static inline void blkiocg_set_start_empty_time(struct blkio_group *blkg) {} -#endif - -#if defined(CONFIG_BLK_CGROUP) || defined(CONFIG_BLK_CGROUP_MODULE) -extern struct blkio_cgroup blkio_root_cgroup; -extern struct blkio_cgroup *cgroup_to_blkio_cgroup(struct cgroup *cgroup); -extern struct blkio_cgroup *task_blkio_cgroup(struct task_struct *tsk); -extern void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg, - struct blkio_group *blkg, void *key, dev_t dev, - enum blkio_policy_id plid); -extern int blkio_alloc_blkg_stats(struct blkio_group *blkg); -extern int blkiocg_del_blkio_group(struct blkio_group *blkg); -extern struct blkio_group *blkiocg_lookup_group(struct blkio_cgroup *blkcg, - void *key); -void blkiocg_update_timeslice_used(struct blkio_group *blkg, - unsigned long time, - unsigned long unaccounted_time); -void blkiocg_update_dispatch_stats(struct blkio_group *blkg, uint64_t bytes, - bool direction, bool sync); -void blkiocg_update_completion_stats(struct blkio_group *blkg, - uint64_t start_time, uint64_t io_start_time, bool direction, bool sync); -void blkiocg_update_io_merged_stats(struct blkio_group *blkg, bool direction, - bool sync); -void blkiocg_update_io_add_stats(struct blkio_group *blkg, - struct blkio_group *curr_blkg, bool direction, bool sync); -void blkiocg_update_io_remove_stats(struct blkio_group *blkg, - bool direction, bool sync); -#else -struct cgroup; -static inline struct blkio_cgroup * -cgroup_to_blkio_cgroup(struct cgroup *cgroup) { return NULL; } -static inline struct blkio_cgroup * -task_blkio_cgroup(struct task_struct *tsk) { return NULL; } - -static inline void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg, - struct blkio_group *blkg, void *key, dev_t dev, - enum blkio_policy_id plid) {} - -static inline int blkio_alloc_blkg_stats(struct blkio_group *blkg) { return 0; } - -static inline int -blkiocg_del_blkio_group(struct blkio_group *blkg) { return 0; } - -static inline struct blkio_group * -blkiocg_lookup_group(struct blkio_cgroup *blkcg, void *key) { return NULL; } -static inline void blkiocg_update_timeslice_used(struct blkio_group *blkg, - unsigned long time, - unsigned long unaccounted_time) -{} -static inline void blkiocg_update_dispatch_stats(struct blkio_group *blkg, - uint64_t bytes, bool direction, bool sync) {} -static inline void blkiocg_update_completion_stats(struct blkio_group *blkg, - uint64_t start_time, uint64_t io_start_time, bool direction, - bool sync) {} -static inline void blkiocg_update_io_merged_stats(struct blkio_group *blkg, - bool direction, bool sync) {} -static inline void blkiocg_update_io_add_stats(struct blkio_group *blkg, - struct blkio_group *curr_blkg, bool direction, bool sync) {} -static inline void blkiocg_update_io_remove_stats(struct blkio_group *blkg, - bool direction, bool sync) {} -#endif -#endif /* _BLK_CGROUP_H */ +struct blkcg_policy { +}; + +static inline struct blkcg *cgroup_to_blkcg(struct cgroup *cgroup) { return NULL; } +static inline struct blkcg *bio_blkcg(struct bio *bio) { return NULL; } +static inline struct blkcg_gq *blkg_lookup(struct blkcg *blkcg, void *key) { return NULL; } +static inline int blkcg_init_queue(struct request_queue *q) { return 0; } +static inline void blkcg_drain_queue(struct request_queue *q) { } +static inline void blkcg_exit_queue(struct request_queue *q) { } +static inline int blkcg_policy_register(struct blkcg_policy *pol) { return 0; } +static inline void blkcg_policy_unregister(struct blkcg_policy *pol) { } +static inline int blkcg_activate_policy(struct request_queue *q, + const struct blkcg_policy *pol) { return 0; } +static inline void blkcg_deactivate_policy(struct request_queue *q, + const struct blkcg_policy *pol) { } + +static inline struct blkg_policy_data *blkg_to_pd(struct blkcg_gq *blkg, + struct blkcg_policy *pol) { return NULL; } +static inline struct blkcg_gq *pd_to_blkg(struct blkg_policy_data *pd) { return NULL; } +static inline char *blkg_path(struct blkcg_gq *blkg) { return NULL; } +static inline void blkg_get(struct blkcg_gq *blkg) { } +static inline void blkg_put(struct blkcg_gq *blkg) { } + +#endif /* CONFIG_BLK_CGROUP */ +#endif /* _BLK_CGROUP_H */ |