#ifndef _BLK_CGROUP_H #define _BLK_CGROUP_H /* * Common Block IO controller cgroup interface * * Based on ideas and code from CFQ, CFS and BFQ: * Copyright (C) 2003 Jens Axboe <axboe@kernel.dk> * * Copyright (C) 2008 Fabio Checconi <fabio@gandalf.sssup.it> * Paolo Valente <paolo.valente@unimore.it> * * Copyright (C) 2009 Vivek Goyal <vgoyal@redhat.com> * Nauman Rafique <nauman@google.com> */ #include <linux/cgroup.h> #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 bytes transferred */ BLKIO_STAT_SERVICE_BYTES, /* Total IOs serviced, post merge */ BLKIO_STAT_SERVICED, /* Total time spent waiting in scheduler queue in ns */ BLKIO_STAT_WAIT_TIME, /* Number of IOs merged */ BLKIO_STAT_MERGED, /* Number of IOs queued up */ BLKIO_STAT_QUEUED, /* All the single valued stats go below this */ BLKIO_STAT_TIME, BLKIO_STAT_SECTORS, #ifdef CONFIG_DEBUG_BLK_CGROUP BLKIO_STAT_AVG_QUEUE_SIZE, BLKIO_STAT_IDLE_TIME, BLKIO_STAT_EMPTY_TIME, BLKIO_STAT_GROUP_WAIT_TIME, BLKIO_STAT_DEQUEUE #endif }; enum stat_sub_type { BLKIO_STAT_READ = 0, BLKIO_STAT_WRITE, BLKIO_STAT_SYNC, BLKIO_STAT_ASYNC, BLKIO_STAT_TOTAL }; /* blkg state flags */ enum blkg_state_flags { BLKG_waiting = 0, BLKG_idling, BLKG_empty, }; 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 blkio_group_stats { /* total disk time and nr sectors dispatched by this group */ uint64_t time; uint64_t sectors; uint64_t stat_arr[BLKIO_STAT_QUEUED + 1][BLKIO_STAT_TOTAL]; #ifdef CONFIG_DEBUG_BLK_CGROUP /* 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 }; 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; /* Need to serialize the stats in the case of reset/update */ spinlock_t stats_lock; struct blkio_group_stats stats; }; struct blkio_policy_node { struct list_head node; dev_t dev; unsigned int weight; }; extern unsigned int blkcg_get_weight(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) (struct blkio_group *blkg, unsigned int weight); struct blkio_policy_ops { blkio_unlink_group_fn *blkio_unlink_group_fn; blkio_update_group_weight_fn *blkio_update_group_weight_fn; }; struct blkio_policy_type { struct list_head list; struct blkio_policy_ops ops; }; /* Blkio controller policy registration */ extern void blkio_policy_register(struct blkio_policy_type *); extern void blkio_policy_unregister(struct blkio_policy_type *); static inline char *blkg_path(struct blkio_group *blkg) { return blkg->path; } #else struct blkio_group { }; struct blkio_policy_type { }; 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 100 #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 void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg, struct blkio_group *blkg, void *key, dev_t dev); 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); 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 void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg, struct blkio_group *blkg, void *key, dev_t dev) {} 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) {} 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 */