diff options
Diffstat (limited to 'block/cfq-iosched.c')
| -rw-r--r-- | block/cfq-iosched.c | 1072 |
1 files changed, 685 insertions, 387 deletions
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index 3c38536bd52..673c977cc2b 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -15,7 +15,9 @@ #include <linux/ioprio.h> #include <linux/blktrace_api.h> #include "blk.h" -#include "cfq.h" +#include "blk-cgroup.h" + +static struct blkcg_policy blkcg_policy_cfq __maybe_unused; /* * tunables @@ -171,8 +173,53 @@ enum wl_type_t { SYNC_WORKLOAD = 2 }; +struct cfqg_stats { +#ifdef CONFIG_CFQ_GROUP_IOSCHED + /* total bytes transferred */ + struct blkg_rwstat service_bytes; + /* total IOs serviced, post merge */ + struct blkg_rwstat serviced; + /* number of ios merged */ + struct blkg_rwstat merged; + /* total time spent on device in ns, may not be accurate w/ queueing */ + struct blkg_rwstat service_time; + /* total time spent waiting in scheduler queue in ns */ + struct blkg_rwstat wait_time; + /* number of IOs queued up */ + struct blkg_rwstat queued; + /* total sectors transferred */ + struct blkg_stat sectors; + /* total disk time and nr sectors dispatched by this group */ + struct blkg_stat time; +#ifdef CONFIG_DEBUG_BLK_CGROUP + /* time not charged to this cgroup */ + struct blkg_stat unaccounted_time; + /* sum of number of ios queued across all samples */ + struct blkg_stat avg_queue_size_sum; + /* count of samples taken for average */ + struct blkg_stat avg_queue_size_samples; + /* how many times this group has been removed from service tree */ + struct blkg_stat dequeue; + /* total time spent waiting for it to be assigned a timeslice. */ + struct blkg_stat group_wait_time; + /* time spent idling for this blkcg_gq */ + struct blkg_stat idle_time; + /* total time with empty current active q with other requests queued */ + struct blkg_stat empty_time; + /* fields after this shouldn't be cleared on stat reset */ + uint64_t start_group_wait_time; + uint64_t start_idle_time; + uint64_t start_empty_time; + uint16_t flags; +#endif /* CONFIG_DEBUG_BLK_CGROUP */ +#endif /* CONFIG_CFQ_GROUP_IOSCHED */ +}; + /* This is per cgroup per device grouping structure */ struct cfq_group { + /* must be the first member */ + struct blkg_policy_data pd; + /* group service_tree member */ struct rb_node rb_node; @@ -180,7 +227,7 @@ struct cfq_group { u64 vdisktime; unsigned int weight; unsigned int new_weight; - bool needs_update; + unsigned int dev_weight; /* number of cfqq currently on this group */ int nr_cfqq; @@ -206,20 +253,21 @@ struct cfq_group { unsigned long saved_workload_slice; enum wl_type_t saved_workload; enum wl_prio_t saved_serving_prio; - struct blkio_group blkg; -#ifdef CONFIG_CFQ_GROUP_IOSCHED - struct hlist_node cfqd_node; - int ref; -#endif + /* number of requests that are on the dispatch list or inside driver */ int dispatched; struct cfq_ttime ttime; + struct cfqg_stats stats; }; struct cfq_io_cq { struct io_cq icq; /* must be the first member */ struct cfq_queue *cfqq[2]; struct cfq_ttime ttime; + int ioprio; /* the current ioprio */ +#ifdef CONFIG_CFQ_GROUP_IOSCHED + uint64_t blkcg_id; /* the current blkcg ID */ +#endif }; /* @@ -229,7 +277,7 @@ struct cfq_data { struct request_queue *queue; /* Root service tree for cfq_groups */ struct cfq_rb_root grp_service_tree; - struct cfq_group root_group; + struct cfq_group *root_group; /* * The priority currently being served @@ -303,12 +351,6 @@ struct cfq_data { struct cfq_queue oom_cfqq; unsigned long last_delayed_sync; - - /* List of cfq groups being managed on this device*/ - struct hlist_head cfqg_list; - - /* Number of groups which are on blkcg->blkg_list */ - unsigned int nr_blkcg_linked_grps; }; static struct cfq_group *cfq_get_next_cfqg(struct cfq_data *cfqd); @@ -371,21 +413,284 @@ CFQ_CFQQ_FNS(deep); CFQ_CFQQ_FNS(wait_busy); #undef CFQ_CFQQ_FNS +static inline struct cfq_group *pd_to_cfqg(struct blkg_policy_data *pd) +{ + return pd ? container_of(pd, struct cfq_group, pd) : NULL; +} + +static inline struct cfq_group *blkg_to_cfqg(struct blkcg_gq *blkg) +{ + return pd_to_cfqg(blkg_to_pd(blkg, &blkcg_policy_cfq)); +} + +static inline struct blkcg_gq *cfqg_to_blkg(struct cfq_group *cfqg) +{ + return pd_to_blkg(&cfqg->pd); +} + +#if defined(CONFIG_CFQ_GROUP_IOSCHED) && defined(CONFIG_DEBUG_BLK_CGROUP) + +/* cfqg stats flags */ +enum cfqg_stats_flags { + CFQG_stats_waiting = 0, + CFQG_stats_idling, + CFQG_stats_empty, +}; + +#define CFQG_FLAG_FNS(name) \ +static inline void cfqg_stats_mark_##name(struct cfqg_stats *stats) \ +{ \ + stats->flags |= (1 << CFQG_stats_##name); \ +} \ +static inline void cfqg_stats_clear_##name(struct cfqg_stats *stats) \ +{ \ + stats->flags &= ~(1 << CFQG_stats_##name); \ +} \ +static inline int cfqg_stats_##name(struct cfqg_stats *stats) \ +{ \ + return (stats->flags & (1 << CFQG_stats_##name)) != 0; \ +} \ + +CFQG_FLAG_FNS(waiting) +CFQG_FLAG_FNS(idling) +CFQG_FLAG_FNS(empty) +#undef CFQG_FLAG_FNS + +/* This should be called with the queue_lock held. */ +static void cfqg_stats_update_group_wait_time(struct cfqg_stats *stats) +{ + unsigned long long now; + + if (!cfqg_stats_waiting(stats)) + return; + + now = sched_clock(); + if (time_after64(now, stats->start_group_wait_time)) + blkg_stat_add(&stats->group_wait_time, + now - stats->start_group_wait_time); + cfqg_stats_clear_waiting(stats); +} + +/* This should be called with the queue_lock held. */ +static void cfqg_stats_set_start_group_wait_time(struct cfq_group *cfqg, + struct cfq_group *curr_cfqg) +{ + struct cfqg_stats *stats = &cfqg->stats; + + if (cfqg_stats_waiting(stats)) + return; + if (cfqg == curr_cfqg) + return; + stats->start_group_wait_time = sched_clock(); + cfqg_stats_mark_waiting(stats); +} + +/* This should be called with the queue_lock held. */ +static void cfqg_stats_end_empty_time(struct cfqg_stats *stats) +{ + unsigned long long now; + + if (!cfqg_stats_empty(stats)) + return; + + now = sched_clock(); + if (time_after64(now, stats->start_empty_time)) + blkg_stat_add(&stats->empty_time, + now - stats->start_empty_time); + cfqg_stats_clear_empty(stats); +} + +static void cfqg_stats_update_dequeue(struct cfq_group *cfqg) +{ + blkg_stat_add(&cfqg->stats.dequeue, 1); +} + +static void cfqg_stats_set_start_empty_time(struct cfq_group *cfqg) +{ + struct cfqg_stats *stats = &cfqg->stats; + + if (blkg_rwstat_sum(&stats->queued)) + return; + + /* + * group is already marked empty. This can happen if cfqq got new + * request in parent group and moved to this group while being added + * to service tree. Just ignore the event and move on. + */ + if (cfqg_stats_empty(stats)) + return; + + stats->start_empty_time = sched_clock(); + cfqg_stats_mark_empty(stats); +} + +static void cfqg_stats_update_idle_time(struct cfq_group *cfqg) +{ + struct cfqg_stats *stats = &cfqg->stats; + + if (cfqg_stats_idling(stats)) { + unsigned long long now = sched_clock(); + + if (time_after64(now, stats->start_idle_time)) + blkg_stat_add(&stats->idle_time, + now - stats->start_idle_time); + cfqg_stats_clear_idling(stats); + } +} + +static void cfqg_stats_set_start_idle_time(struct cfq_group *cfqg) +{ + struct cfqg_stats *stats = &cfqg->stats; + + BUG_ON(cfqg_stats_idling(stats)); + + stats->start_idle_time = sched_clock(); + cfqg_stats_mark_idling(stats); +} + +static void cfqg_stats_update_avg_queue_size(struct cfq_group *cfqg) +{ + struct cfqg_stats *stats = &cfqg->stats; + + blkg_stat_add(&stats->avg_queue_size_sum, + blkg_rwstat_sum(&stats->queued)); + blkg_stat_add(&stats->avg_queue_size_samples, 1); + cfqg_stats_update_group_wait_time(stats); +} + +#else /* CONFIG_CFQ_GROUP_IOSCHED && CONFIG_DEBUG_BLK_CGROUP */ + +static inline void cfqg_stats_set_start_group_wait_time(struct cfq_group *cfqg, struct cfq_group *curr_cfqg) { } +static inline void cfqg_stats_end_empty_time(struct cfqg_stats *stats) { } +static inline void cfqg_stats_update_dequeue(struct cfq_group *cfqg) { } +static inline void cfqg_stats_set_start_empty_time(struct cfq_group *cfqg) { } +static inline void cfqg_stats_update_idle_time(struct cfq_group *cfqg) { } +static inline void cfqg_stats_set_start_idle_time(struct cfq_group *cfqg) { } +static inline void cfqg_stats_update_avg_queue_size(struct cfq_group *cfqg) { } + +#endif /* CONFIG_CFQ_GROUP_IOSCHED && CONFIG_DEBUG_BLK_CGROUP */ + #ifdef CONFIG_CFQ_GROUP_IOSCHED -#define cfq_log_cfqq(cfqd, cfqq, fmt, args...) \ + +static inline void cfqg_get(struct cfq_group *cfqg) +{ + return blkg_get(cfqg_to_blkg(cfqg)); +} + +static inline void cfqg_put(struct cfq_group *cfqg) +{ + return blkg_put(cfqg_to_blkg(cfqg)); +} + +#define cfq_log_cfqq(cfqd, cfqq, fmt, args...) do { \ + char __pbuf[128]; \ + \ + blkg_path(cfqg_to_blkg((cfqq)->cfqg), __pbuf, sizeof(__pbuf)); \ blk_add_trace_msg((cfqd)->queue, "cfq%d%c %s " fmt, (cfqq)->pid, \ - cfq_cfqq_sync((cfqq)) ? 'S' : 'A', \ - blkg_path(&(cfqq)->cfqg->blkg), ##args) + cfq_cfqq_sync((cfqq)) ? 'S' : 'A', \ + __pbuf, ##args); \ +} while (0) -#define cfq_log_cfqg(cfqd, cfqg, fmt, args...) \ - blk_add_trace_msg((cfqd)->queue, "%s " fmt, \ - blkg_path(&(cfqg)->blkg), ##args) \ +#define cfq_log_cfqg(cfqd, cfqg, fmt, args...) do { \ + char __pbuf[128]; \ + \ + blkg_path(cfqg_to_blkg(cfqg), __pbuf, sizeof(__pbuf)); \ + blk_add_trace_msg((cfqd)->queue, "%s " fmt, __pbuf, ##args); \ +} while (0) + +static inline void cfqg_stats_update_io_add(struct cfq_group *cfqg, + struct cfq_group *curr_cfqg, int rw) +{ + blkg_rwstat_add(&cfqg->stats.queued, rw, 1); + cfqg_stats_end_empty_time(&cfqg->stats); + cfqg_stats_set_start_group_wait_time(cfqg, curr_cfqg); +} + +static inline void cfqg_stats_update_timeslice_used(struct cfq_group *cfqg, + unsigned long time, unsigned long unaccounted_time) +{ + blkg_stat_add(&cfqg->stats.time, time); +#ifdef CONFIG_DEBUG_BLK_CGROUP + blkg_stat_add(&cfqg->stats.unaccounted_time, unaccounted_time); +#endif +} + +static inline void cfqg_stats_update_io_remove(struct cfq_group *cfqg, int rw) +{ + blkg_rwstat_add(&cfqg->stats.queued, rw, -1); +} + +static inline void cfqg_stats_update_io_merged(struct cfq_group *cfqg, int rw) +{ + blkg_rwstat_add(&cfqg->stats.merged, rw, 1); +} + +static inline void cfqg_stats_update_dispatch(struct cfq_group *cfqg, + uint64_t bytes, int rw) +{ + blkg_stat_add(&cfqg->stats.sectors, bytes >> 9); + blkg_rwstat_add(&cfqg->stats.serviced, rw, 1); + blkg_rwstat_add(&cfqg->stats.service_bytes, rw, bytes); +} + +static inline void cfqg_stats_update_completion(struct cfq_group *cfqg, + uint64_t start_time, uint64_t io_start_time, int rw) +{ + struct cfqg_stats *stats = &cfqg->stats; + unsigned long long now = sched_clock(); + + if (time_after64(now, io_start_time)) + blkg_rwstat_add(&stats->service_time, rw, now - io_start_time); + if (time_after64(io_start_time, start_time)) + blkg_rwstat_add(&stats->wait_time, rw, + io_start_time - start_time); +} + +static void cfq_pd_reset_stats(struct blkcg_gq *blkg) +{ + struct cfq_group *cfqg = blkg_to_cfqg(blkg); + struct cfqg_stats *stats = &cfqg->stats; + + /* queued stats shouldn't be cleared */ + blkg_rwstat_reset(&stats->service_bytes); + blkg_rwstat_reset(&stats->serviced); + blkg_rwstat_reset(&stats->merged); + blkg_rwstat_reset(&stats->service_time); + blkg_rwstat_reset(&stats->wait_time); + blkg_stat_reset(&stats->time); +#ifdef CONFIG_DEBUG_BLK_CGROUP + blkg_stat_reset(&stats->unaccounted_time); + blkg_stat_reset(&stats->avg_queue_size_sum); + blkg_stat_reset(&stats->avg_queue_size_samples); + blkg_stat_reset(&stats->dequeue); + blkg_stat_reset(&stats->group_wait_time); + blkg_stat_reset(&stats->idle_time); + blkg_stat_reset(&stats->empty_time); +#endif +} + +#else /* CONFIG_CFQ_GROUP_IOSCHED */ + +static inline void cfqg_get(struct cfq_group *cfqg) { } +static inline void cfqg_put(struct cfq_group *cfqg) { } -#else #define cfq_log_cfqq(cfqd, cfqq, fmt, args...) \ blk_add_trace_msg((cfqd)->queue, "cfq%d " fmt, (cfqq)->pid, ##args) #define cfq_log_cfqg(cfqd, cfqg, fmt, args...) do {} while (0) -#endif + +static inline void cfqg_stats_update_io_add(struct cfq_group *cfqg, + struct cfq_group *curr_cfqg, int rw) { } +static inline void cfqg_stats_update_timeslice_used(struct cfq_group *cfqg, + unsigned long time, unsigned long unaccounted_time) { } +static inline void cfqg_stats_update_io_remove(struct cfq_group *cfqg, int rw) { } +static inline void cfqg_stats_update_io_merged(struct cfq_group *cfqg, int rw) { } +static inline void cfqg_stats_update_dispatch(struct cfq_group *cfqg, + uint64_t bytes, int rw) { } +static inline void cfqg_stats_update_completion(struct cfq_group *cfqg, + uint64_t start_time, uint64_t io_start_time, int rw) { } + +#endif /* CONFIG_CFQ_GROUP_IOSCHED */ + #define cfq_log(cfqd, fmt, args...) \ blk_add_trace_msg((cfqd)->queue, "cfq " fmt, ##args) @@ -466,8 +771,9 @@ static inline int cfqg_busy_async_queues(struct cfq_data *cfqd, } static void cfq_dispatch_insert(struct request_queue *, struct request *); -static struct cfq_queue *cfq_get_queue(struct cfq_data *, bool, - struct io_context *, gfp_t); +static struct cfq_queue *cfq_get_queue(struct cfq_data *cfqd, bool is_sync, + struct cfq_io_cq *cic, struct bio *bio, + gfp_t gfp_mask); static inline struct cfq_io_cq *icq_to_cic(struct io_cq *icq) { @@ -545,7 +851,7 @@ static inline u64 cfq_scale_slice(unsigned long delta, struct cfq_group *cfqg) { u64 d = delta << CFQ_SERVICE_SHIFT; - d = d * BLKIO_WEIGHT_DEFAULT; + d = d * CFQ_WEIGHT_DEFAULT; do_div(d, cfqg->weight); return d; } @@ -872,9 +1178,9 @@ static void cfq_update_group_weight(struct cfq_group *cfqg) { BUG_ON(!RB_EMPTY_NODE(&cfqg->rb_node)); - if (cfqg->needs_update) { + if (cfqg->new_weight) { cfqg->weight = cfqg->new_weight; - cfqg->needs_update = false; + cfqg->new_weight = 0; } } @@ -936,7 +1242,7 @@ cfq_group_notify_queue_del(struct cfq_data *cfqd, struct cfq_group *cfqg) cfq_log_cfqg(cfqd, cfqg, "del_from_rr group"); cfq_group_service_tree_del(st, cfqg); cfqg->saved_workload_slice = 0; - cfq_blkiocg_update_dequeue_stats(&cfqg->blkg, 1); + cfqg_stats_update_dequeue(cfqg); } static inline unsigned int cfq_cfqq_slice_usage(struct cfq_queue *cfqq, @@ -1008,178 +1314,59 @@ static void cfq_group_served(struct cfq_data *cfqd, struct cfq_group *cfqg, "sl_used=%u disp=%u charge=%u iops=%u sect=%lu", used_sl, cfqq->slice_dispatch, charge, iops_mode(cfqd), cfqq->nr_sectors); - cfq_blkiocg_update_timeslice_used(&cfqg->blkg, used_sl, - unaccounted_sl); - cfq_blkiocg_set_start_empty_time(&cfqg->blkg); + cfqg_stats_update_timeslice_used(cfqg, used_sl, unaccounted_sl); + cfqg_stats_set_start_empty_time(cfqg); } -#ifdef CONFIG_CFQ_GROUP_IOSCHED -static inline struct cfq_group *cfqg_of_blkg(struct blkio_group *blkg) -{ - if (blkg) - return container_of(blkg, struct cfq_group, blkg); - return NULL; -} - -static void cfq_update_blkio_group_weight(void *key, struct blkio_group *blkg, - unsigned int weight) -{ - struct cfq_group *cfqg = cfqg_of_blkg(blkg); - cfqg->new_weight = weight; - cfqg->needs_update = true; -} - -static void cfq_init_add_cfqg_lists(struct cfq_data *cfqd, - struct cfq_group *cfqg, struct blkio_cgroup *blkcg) -{ - struct backing_dev_info *bdi = &cfqd->queue->backing_dev_info; - unsigned int major, minor; - - /* - * Add group onto cgroup list. It might happen that bdi->dev is - * not initialized yet. Initialize this new group without major - * and minor info and this info will be filled in once a new thread - * comes for IO. - */ - if (bdi->dev) { - sscanf(dev_name(bdi->dev), "%u:%u", &major, &minor); - cfq_blkiocg_add_blkio_group(blkcg, &cfqg->blkg, - (void *)cfqd, MKDEV(major, minor)); - } else - cfq_blkiocg_add_blkio_group(blkcg, &cfqg->blkg, - (void *)cfqd, 0); - - cfqd->nr_blkcg_linked_grps++; - cfqg->weight = blkcg_get_weight(blkcg, cfqg->blkg.dev); - - /* Add group on cfqd list */ - hlist_add_head(&cfqg->cfqd_node, &cfqd->cfqg_list); -} - -/* - * Should be called from sleepable context. No request queue lock as per - * cpu stats are allocated dynamically and alloc_percpu needs to be called - * from sleepable context. +/** + * cfq_init_cfqg_base - initialize base part of a cfq_group + * @cfqg: cfq_group to initialize + * + * Initialize the base part which is used whether %CONFIG_CFQ_GROUP_IOSCHED + * is enabled or not. */ -static struct cfq_group * cfq_alloc_cfqg(struct cfq_data *cfqd) +static void cfq_init_cfqg_base(struct cfq_group *cfqg) { - struct cfq_group *cfqg = NULL; - int i, j, ret; struct cfq_rb_root *st; - - cfqg = kzalloc_node(sizeof(*cfqg), GFP_ATOMIC, cfqd->queue->node); - if (!cfqg) - return NULL; + int i, j; for_each_cfqg_st(cfqg, i, j, st) *st = CFQ_RB_ROOT; RB_CLEAR_NODE(&cfqg->rb_node); cfqg->ttime.last_end_request = jiffies; - - /* - * Take the initial reference that will be released on destroy - * This can be thought of a joint reference by cgroup and - * elevator which will be dropped by either elevator exit - * or cgroup deletion path depending on who is exiting first. - */ - cfqg->ref = 1; - - ret = blkio_alloc_blkg_stats(&cfqg->blkg); - if (ret) { - kfree(cfqg); - return NULL; - } - - return cfqg; } -static struct cfq_group * -cfq_find_cfqg(struct cfq_data *cfqd, struct blkio_cgroup *blkcg) +#ifdef CONFIG_CFQ_GROUP_IOSCHED +static void cfq_pd_init(struct blkcg_gq *blkg) { - struct cfq_group *cfqg = NULL; - void *key = cfqd; - struct backing_dev_info *bdi = &cfqd->queue->backing_dev_info; - unsigned int major, minor; - - /* - * This is the common case when there are no blkio cgroups. - * Avoid lookup in this case - */ - if (blkcg == &blkio_root_cgroup) - cfqg = &cfqd->root_group; - else - cfqg = cfqg_of_blkg(blkiocg_lookup_group(blkcg, key)); - - if (cfqg && !cfqg->blkg.dev && bdi->dev && dev_name(bdi->dev)) { - sscanf(dev_name(bdi->dev), "%u:%u", &major, &minor); - cfqg->blkg.dev = MKDEV(major, minor); - } + struct cfq_group *cfqg = blkg_to_cfqg(blkg); - return cfqg; + cfq_init_cfqg_base(cfqg); + cfqg->weight = blkg->blkcg->cfq_weight; } /* * Search for the cfq group current task belongs to. request_queue lock must * be held. */ -static struct cfq_group *cfq_get_cfqg(struct cfq_data *cfqd) +static struct cfq_group *cfq_lookup_create_cfqg(struct cfq_data *cfqd, + struct blkcg *blkcg) { - struct blkio_cgroup *blkcg; - struct cfq_group *cfqg = NULL, *__cfqg = NULL; struct request_queue *q = cfqd->queue; + struct cfq_group *cfqg = NULL; - rcu_read_lock(); - blkcg = task_blkio_cgroup(current); - cfqg = cfq_find_cfqg(cfqd, blkcg); - if (cfqg) { - rcu_read_unlock(); - return cfqg; - } - - /* - * Need to allocate a group. Allocation of group also needs allocation - * of per cpu stats which in-turn takes a mutex() and can block. Hence - * we need to drop rcu lock and queue_lock before we call alloc. - * - * Not taking any queue reference here and assuming that queue is - * around by the time we return. CFQ queue allocation code does - * the same. It might be racy though. - */ - - rcu_read_unlock(); - spin_unlock_irq(q->queue_lock); - - cfqg = cfq_alloc_cfqg(cfqd); - - spin_lock_irq(q->queue_lock); - - rcu_read_lock(); - blkcg = task_blkio_cgroup(current); - - /* - * If some other thread already allocated the group while we were - * not holding queue lock, free up the group - */ - __cfqg = cfq_find_cfqg(cfqd, blkcg); + /* avoid lookup for the common case where there's no blkcg */ + if (blkcg == &blkcg_root) { + cfqg = cfqd->root_group; + } else { + struct blkcg_gq *blkg; - if (__cfqg) { - kfree(cfqg); - rcu_read_unlock(); - return __cfqg; + blkg = blkg_lookup_create(blkcg, q); + if (!IS_ERR(blkg)) + cfqg = blkg_to_cfqg(blkg); } - if (!cfqg) - cfqg = &cfqd->root_group; - - cfq_init_add_cfqg_lists(cfqd, cfqg, blkcg); - rcu_read_unlock(); - return cfqg; -} - -static inline struct cfq_group *cfq_ref_get_cfqg(struct cfq_group *cfqg) -{ - cfqg->ref++; return cfqg; } @@ -1187,94 +1374,224 @@ static void cfq_link_cfqq_cfqg(struct cfq_queue *cfqq, struct cfq_group *cfqg) { /* Currently, all async queues are mapped to root group */ if (!cfq_cfqq_sync(cfqq)) - cfqg = &cfqq->cfqd->root_group; + cfqg = cfqq->cfqd->root_group; cfqq->cfqg = cfqg; /* cfqq reference on cfqg */ - cfqq->cfqg->ref++; + cfqg_get(cfqg); } -static void cfq_put_cfqg(struct cfq_group *cfqg) +static u64 cfqg_prfill_weight_device(struct seq_file *sf, + struct blkg_policy_data *pd, int off) { - struct cfq_rb_root *st; - int i, j; + struct cfq_group *cfqg = pd_to_cfqg(pd); - BUG_ON(cfqg->ref <= 0); - cfqg->ref--; - if (cfqg->ref) - return; - for_each_cfqg_st(cfqg, i, j, st) - BUG_ON(!RB_EMPTY_ROOT(&st->rb)); - free_percpu(cfqg->blkg.stats_cpu); - kfree(cfqg); + if (!cfqg->dev_weight) + return 0; + return __blkg_prfill_u64(sf, pd, cfqg->dev_weight); } -static void cfq_destroy_cfqg(struct cfq_data *cfqd, struct cfq_group *cfqg) +static int cfqg_print_weight_device(struct cgroup *cgrp, struct cftype *cft, + struct seq_file *sf) { - /* Something wrong if we are trying to remove same group twice */ - BUG_ON(hlist_unhashed(&cfqg->cfqd_node)); + blkcg_print_blkgs(sf, cgroup_to_blkcg(cgrp), + cfqg_prfill_weight_device, &blkcg_policy_cfq, 0, + false); + return 0; +} - hlist_del_init(&cfqg->cfqd_node); +static int cfq_print_weight(struct cgroup *cgrp, struct cftype *cft, + struct seq_file *sf) +{ + seq_printf(sf, "%u\n", cgroup_to_blkcg(cgrp)->cfq_weight); + return 0; +} - BUG_ON(cfqd->nr_blkcg_linked_grps <= 0); - cfqd->nr_blkcg_linked_grps--; +static int cfqg_set_weight_device(struct cgroup *cgrp, struct cftype *cft, + const char *buf) +{ + struct blkcg *blkcg = cgroup_to_blkcg(cgrp); + struct blkg_conf_ctx ctx; + struct cfq_group *cfqg; + int ret; - /* - * Put the reference taken at the time of creation so that when all - * queues are gone, group can be destroyed. - */ - cfq_put_cfqg(cfqg); + ret = blkg_conf_prep(blkcg, &blkcg_policy_cfq, buf, &ctx); + if (ret) + return ret; + + ret = -EINVAL; + cfqg = blkg_to_cfqg(ctx.blkg); + if (!ctx.v || (ctx.v >= CFQ_WEIGHT_MIN && ctx.v <= CFQ_WEIGHT_MAX)) { + cfqg->dev_weight = ctx.v; + cfqg->new_weight = cfqg->dev_weight ?: blkcg->cfq_weight; + ret = 0; + } + + blkg_conf_finish(&ctx); + return ret; } -static void cfq_release_cfq_groups(struct cfq_data *cfqd) +static int cfq_set_weight(struct cgroup *cgrp, struct cftype *cft, u64 val) { - struct hlist_node *pos, *n; - struct cfq_group *cfqg; + struct blkcg *blkcg = cgroup_to_blkcg(cgrp); + struct blkcg_gq *blkg; + struct hlist_node *n; - hlist_for_each_entry_safe(cfqg, pos, n, &cfqd->cfqg_list, cfqd_node) { - /* - * If cgroup removal path got to blk_group first and removed - * it from cgroup list, then it will take care of destroying - * cfqg also. - */ - if (!cfq_blkiocg_del_blkio_group(&cfqg->blkg)) - cfq_destroy_cfqg(cfqd, cfqg); + if (val < CFQ_WEIGHT_MIN || val > CFQ_WEIGHT_MAX) + return -EINVAL; + + spin_lock_irq(&blkcg->lock); + blkcg->cfq_weight = (unsigned int)val; + + hlist_for_each_entry(blkg, n, &blkcg->blkg_list, blkcg_node) { + struct cfq_group *cfqg = blkg_to_cfqg(blkg); + + if (cfqg && !cfqg->dev_weight) + cfqg->new_weight = blkcg->cfq_weight; } + + spin_unlock_irq(&blkcg->lock); + return 0; } -/* - * Blk cgroup controller notification saying that blkio_group object is being - * delinked as associated cgroup object is going away. That also means that - * no new IO will come in this group. So get rid of this group as soon as - * any pending IO in the group is finished. - * - * This function is called under rcu_read_lock(). key is the rcu protected - * pointer. That means "key" is a valid cfq_data pointer as long as we are rcu - * read lock. - * - * "key" was fetched from blkio_group under blkio_cgroup->lock. That means - * it should not be NULL as even if elevator was exiting, cgroup deltion - * path got to it first. - */ -static void cfq_unlink_blkio_group(void *key, struct blkio_group *blkg) +static int cfqg_print_stat(struct cgroup *cgrp, struct cftype *cft, + struct seq_file *sf) { - unsigned long flags; - struct cfq_data *cfqd = key; + struct blkcg *blkcg = cgroup_to_blkcg(cgrp); - spin_lock_irqsave(cfqd->queue->queue_lock, flags); - cfq_destroy_cfqg(cfqd, cfqg_of_blkg(blkg)); - spin_unlock_irqrestore(cfqd->queue->queue_lock, flags); + blkcg_print_blkgs(sf, blkcg, blkg_prfill_stat, &blkcg_policy_cfq, + cft->private, false); + return 0; } -#else /* GROUP_IOSCHED */ -static struct cfq_group *cfq_get_cfqg(struct cfq_data *cfqd) +static int cfqg_print_rwstat(struct cgroup *cgrp, struct cftype *cft, + struct seq_file *sf) { - return &cfqd->root_group; + struct blkcg *blkcg = cgroup_to_blkcg(cgrp); + + blkcg_print_blkgs(sf, blkcg, blkg_prfill_rwstat, &blkcg_policy_cfq, + cft->private, true); + return 0; } -static inline struct cfq_group *cfq_ref_get_cfqg(struct cfq_group *cfqg) +#ifdef CONFIG_DEBUG_BLK_CGROUP +static u64 cfqg_prfill_avg_queue_size(struct seq_file *sf, + struct blkg_policy_data *pd, int off) { - return cfqg; + struct cfq_group *cfqg = pd_to_cfqg(pd); + u64 samples = blkg_stat_read(&cfqg->stats.avg_queue_size_samples); + u64 v = 0; + + if (samples) { + v = blkg_stat_read(&cfqg->stats.avg_queue_size_sum); + do_div(v, samples); + } + __blkg_prfill_u64(sf, pd, v); + return 0; +} + +/* print avg_queue_size */ +static int cfqg_print_avg_queue_size(struct cgroup *cgrp, struct cftype *cft, + struct seq_file *sf) +{ + struct blkcg *blkcg = cgroup_to_blkcg(cgrp); + + blkcg_print_blkgs(sf, blkcg, cfqg_prfill_avg_queue_size, + &blkcg_policy_cfq, 0, false); + return 0; +} +#endif /* CONFIG_DEBUG_BLK_CGROUP */ + +static struct cftype cfq_blkcg_files[] = { + { + .name = "weight_device", + .read_seq_string = cfqg_print_weight_device, + .write_string = cfqg_set_weight_device, + .max_write_len = 256, + }, + { + .name = "weight", + .read_seq_string = cfq_print_weight, + .write_u64 = cfq_set_weight, + }, + { + .name = "time", + .private = offsetof(struct cfq_group, stats.time), + .read_seq_string = cfqg_print_stat, + }, + { + .name = "sectors", + .private = offsetof(struct cfq_group, stats.sectors), + .read_seq_string = cfqg_print_stat, + }, + { + .name = "io_service_bytes", + .private = offsetof(struct cfq_group, stats.service_bytes), + .read_seq_string = cfqg_print_rwstat, + }, + { + .name = "io_serviced", + .private = offsetof(struct cfq_group, stats.serviced), + .read_seq_string = cfqg_print_rwstat, + }, + { + .name = "io_service_time", + .private = offsetof(struct cfq_group, stats.service_time), + .read_seq_string = cfqg_print_rwstat, + }, + { + .name = "io_wait_time", + .private = offsetof(struct cfq_group, stats.wait_time), + .read_seq_string = cfqg_print_rwstat, + }, + { + .name = "io_merged", + .private = offsetof(struct cfq_group, stats.merged), + .read_seq_string = cfqg_print_rwstat, + }, + { + .name = "io_queued", + .private = offsetof(struct cfq_group, stats.queued), + .read_seq_string = cfqg_print_rwstat, + }, +#ifdef CONFIG_DEBUG_BLK_CGROUP + { + .name = "avg_queue_size", + .read_seq_string = cfqg_print_avg_queue_size, + }, + { + .name = "group_wait_time", + .private = offsetof(struct cfq_group, stats.group_wait_time), + .read_seq_string = cfqg_print_stat, + }, + { + .name = "idle_time", + .private = offsetof(struct cfq_group, stats.idle_time), + .read_seq_string = cfqg_print_stat, + }, + { + .name = "empty_time", + .private = offsetof(struct cfq_group, stats.empty_time), + .read_seq_string = cfqg_print_stat, + }, + { + .name = "dequeue", + .private = offsetof(struct cfq_group, stats.dequeue), + .read_seq_string = cfqg_print_stat, + }, + { + .name = "unaccounted_time", + .private = offsetof(struct cfq_group, stats.unaccounted_time), + .read_seq_string = cfqg_print_stat, + }, +#endif /* CONFIG_DEBUG_BLK_CGROUP */ + { } /* terminate */ +}; +#else /* GROUP_IOSCHED */ +static struct cfq_group *cfq_lookup_create_cfqg(struct cfq_data *cfqd, + struct blkcg *blkcg) +{ + return cfqd->root_group; } static inline void @@ -1282,9 +1599,6 @@ cfq_link_cfqq_cfqg(struct cfq_queue *cfqq, struct cfq_group *cfqg) { cfqq->cfqg = cfqg; } -static void cfq_release_cfq_groups(struct cfq_data *cfqd) {} -static inline void cfq_put_cfqg(struct cfq_group *cfqg) {} - #endif /* GROUP_IOSCHED */ /* @@ -1551,12 +1865,10 @@ static void cfq_reposition_rq_rb(struct cfq_queue *cfqq, struct request *rq) { elv_rb_del(&cfqq->sort_list, rq); cfqq->queued[rq_is_sync(rq)]--; - cfq_blkiocg_update_io_remove_stats(&(RQ_CFQG(rq))->blkg, - rq_data_dir(rq), rq_is_sync(rq)); + cfqg_stats_update_io_remove(RQ_CFQG(rq), rq->cmd_flags); cfq_add_rq_rb(rq); - cfq_blkiocg_update_io_add_stats(&(RQ_CFQG(rq))->blkg, - &cfqq->cfqd->serving_group->blkg, rq_data_dir(rq), - rq_is_sync(rq)); + cfqg_stats_update_io_add(RQ_CFQG(rq), cfqq->cfqd->serving_group, + rq->cmd_flags); } static struct request * @@ -1612,8 +1924,7 @@ static void cfq_remove_request(struct request *rq) cfq_del_rq_rb(rq); cfqq->cfqd->rq_queued--; - cfq_blkiocg_update_io_remove_stats(&(RQ_CFQG(rq))->blkg, - rq_data_dir(rq), rq_is_sync(rq)); + cfqg_stats_update_io_remove(RQ_CFQG(rq), rq->cmd_flags); if (rq->cmd_flags & REQ_PRIO) { WARN_ON(!cfqq->prio_pending); cfqq->prio_pending--; @@ -1648,8 +1959,7 @@ static void cfq_merged_request(struct request_queue *q, struct request *req, static void cfq_bio_merged(struct request_queue *q, struct request *req, struct bio *bio) { - cfq_blkiocg_update_io_merged_stats(&(RQ_CFQG(req))->blkg, - bio_data_dir(bio), cfq_bio_sync(bio)); + cfqg_stats_update_io_merged(RQ_CFQG(req), bio->bi_rw); } static void @@ -1671,8 +1981,7 @@ cfq_merged_requests(struct request_queue *q, struct request *rq, if (cfqq->next_rq == next) cfqq->next_rq = rq; cfq_remove_request(next); - cfq_blkiocg_update_io_merged_stats(&(RQ_CFQG(rq))->blkg, - rq_data_dir(next), rq_is_sync(next)); + cfqg_stats_update_io_merged(RQ_CFQG(rq), next->cmd_flags); cfqq = RQ_CFQQ(next); /* @@ -1713,7 +2022,7 @@ static int cfq_allow_merge(struct request_queue *q, struct request *rq, static inline void cfq_del_timer(struct cfq_data *cfqd, struct cfq_queue *cfqq) { del_timer(&cfqd->idle_slice_timer); - cfq_blkiocg_update_idle_time_stats(&cfqq->cfqg->blkg); + cfqg_stats_update_idle_time(cfqq->cfqg); } static void __cfq_set_active_queue(struct cfq_data *cfqd, @@ -1722,7 +2031,7 @@ static void __cfq_set_active_queue(struct cfq_data *cfqd, if (cfqq) { cfq_log_cfqq(cfqd, cfqq, "set_active wl_prio:%d wl_type:%d", cfqd->serving_prio, cfqd->serving_type); - cfq_blkiocg_update_avg_queue_size_stats(&cfqq->cfqg->blkg); + cfqg_stats_update_avg_queue_size(cfqq->cfqg); cfqq->slice_start = 0; cfqq->dispatch_start = jiffies; cfqq->allocated_slice = 0; @@ -2043,7 +2352,7 @@ static void cfq_arm_slice_timer(struct cfq_data *cfqd) * task has exited, don't wait */ cic = cfqd->active_cic; - if (!cic || !atomic_read(&cic->icq.ioc->nr_tasks)) + if (!cic || !atomic_read(&cic->icq.ioc->active_ref)) return; /* @@ -2070,7 +2379,7 @@ static void cfq_arm_slice_timer(struct cfq_data *cfqd) sl = cfqd->cfq_slice_idle; mod_timer(&cfqd->idle_slice_timer, jiffies + sl); - cfq_blkiocg_update_set_idle_time_stats(&cfqq->cfqg->blkg); + cfqg_stats_set_start_idle_time(cfqq->cfqg); cfq_log_cfqq(cfqd, cfqq, "arm_idle: %lu group_idle: %d", sl, group_idle ? 1 : 0); } @@ -2093,8 +2402,7 @@ static void cfq_dispatch_insert(struct request_queue *q, struct request *rq) cfqd->rq_in_flight[cfq_cfqq_sync(cfqq)]++; cfqq->nr_sectors += blk_rq_sectors(rq); - cfq_blkiocg_update_dispatch_stats(&cfqq->cfqg->blkg, blk_rq_bytes(rq), - rq_data_dir(rq), rq_is_sync(rq)); + cfqg_stats_update_dispatch(cfqq->cfqg, blk_rq_bytes(rq), rq->cmd_flags); } /* @@ -2677,7 +2985,7 @@ static void cfq_put_queue(struct cfq_queue *cfqq) BUG_ON(cfq_cfqq_on_rr(cfqq)); kmem_cache_free(cfq_pool, cfqq); - cfq_put_cfqg(cfqg); + cfqg_put(cfqg); } static void cfq_put_cooperator(struct cfq_queue *cfqq) @@ -2736,7 +3044,7 @@ static void cfq_exit_icq(struct io_cq *icq) } } -static void cfq_init_prio_data(struct cfq_queue *cfqq, struct io_context *ioc) +static void cfq_init_prio_data(struct cfq_queue *cfqq, struct cfq_io_cq *cic) { struct task_struct *tsk = current; int ioprio_class; @@ -2744,7 +3052,7 @@ static void cfq_init_prio_data(struct cfq_queue *cfqq, struct io_context *ioc) if (!cfq_cfqq_prio_changed(cfqq)) return; - ioprio_class = IOPRIO_PRIO_CLASS(ioc->ioprio); + ioprio_class = IOPRIO_PRIO_CLASS(cic->ioprio); switch (ioprio_class) { default: printk(KERN_ERR "cfq: bad prio %x\n", ioprio_class); @@ -2756,11 +3064,11 @@ static void cfq_init_prio_data(struct cfq_queue *cfqq, struct io_context *ioc) cfqq->ioprio_class = task_nice_ioclass(tsk); break; case IOPRIO_CLASS_RT: - cfqq->ioprio = task_ioprio(ioc); + cfqq->ioprio = IOPRIO_PRIO_DATA(cic->ioprio); cfqq->ioprio_class = IOPRIO_CLASS_RT; break; case IOPRIO_CLASS_BE: - cfqq->ioprio = task_ioprio(ioc); + cfqq->ioprio = IOPRIO_PRIO_DATA(cic->ioprio); cfqq->ioprio_class = IOPRIO_CLASS_BE; break; case IOPRIO_CLASS_IDLE: @@ -2778,19 +3086,24 @@ static void cfq_init_prio_data(struct cfq_queue *cfqq, struct io_context *ioc) cfq_clear_cfqq_prio_changed(cfqq); } -static void changed_ioprio(struct cfq_io_cq *cic) +static void check_ioprio_changed(struct cfq_io_cq *cic, struct bio *bio) { + int ioprio = cic->icq.ioc->ioprio; struct cfq_data *cfqd = cic_to_cfqd(cic); struct cfq_queue *cfqq; - if (unlikely(!cfqd)) + /* + * Check whether ioprio has changed. The condition may trigger + * spuriously on a newly created cic but there's no harm. + */ + if (unlikely(!cfqd) || likely(cic->ioprio == ioprio)) return; cfqq = cic->cfqq[BLK_RW_ASYNC]; if (cfqq) { struct cfq_queue *new_cfqq; - new_cfqq = cfq_get_queue(cfqd, BLK_RW_ASYNC, cic->icq.ioc, - GFP_ATOMIC); + new_cfqq = cfq_get_queue(cfqd, BLK_RW_ASYNC, cic, bio, + GFP_ATOMIC); if (new_cfqq) { cic->cfqq[BLK_RW_ASYNC] = new_cfqq; cfq_put_queue(cfqq); @@ -2800,6 +3113,8 @@ static void changed_ioprio(struct cfq_io_cq *cic) cfqq = cic->cfqq[BLK_RW_SYNC]; if (cfqq) cfq_mark_cfqq_prio_changed(cfqq); + + cic->ioprio = ioprio; } static void cfq_init_cfqq(struct cfq_data *cfqd, struct cfq_queue *cfqq, @@ -2823,17 +3138,24 @@ static void cfq_init_cfqq(struct cfq_data *cfqd, struct cfq_queue *cfqq, } #ifdef CONFIG_CFQ_GROUP_IOSCHED -static void changed_cgroup(struct cfq_io_cq *cic) +static void check_blkcg_changed(struct cfq_io_cq *cic, struct bio *bio) { - struct cfq_queue *sync_cfqq = cic_to_cfqq(cic, 1); struct cfq_data *cfqd = cic_to_cfqd(cic); - struct request_queue *q; + struct cfq_queue *sync_cfqq; + uint64_t id; - if (unlikely(!cfqd)) - return; + rcu_read_lock(); + id = bio_blkcg(bio)->id; + rcu_read_unlock(); - q = cfqd->queue; + /* + * Check whether blkcg has changed. The condition may trigger + * spuriously on a newly created cic but there's no harm. + */ + if (unlikely(!cfqd) || likely(cic->blkcg_id == id)) + return; + sync_cfqq = cic_to_cfqq(cic, 1); if (sync_cfqq) { /* * Drop reference to sync queue. A new sync queue will be @@ -2843,21 +3165,26 @@ static void changed_cgroup(struct cfq_io_cq *cic) cic_set_cfqq(cic, NULL, 1); cfq_put_queue(sync_cfqq); } + + cic->blkcg_id = id; } +#else +static inline void check_blkcg_changed(struct cfq_io_cq *cic, struct bio *bio) { } #endif /* CONFIG_CFQ_GROUP_IOSCHED */ static struct cfq_queue * -cfq_find_alloc_queue(struct cfq_data *cfqd, bool is_sync, - struct io_context *ioc, gfp_t gfp_mask) +cfq_find_alloc_queue(struct cfq_data *cfqd, bool is_sync, struct cfq_io_cq *cic, + struct bio *bio, gfp_t gfp_mask) { + struct blkcg *blkcg; struct cfq_queue *cfqq, *new_cfqq = NULL; - struct cfq_io_cq *cic; struct cfq_group *cfqg; retry: - cfqg = cfq_get_cfqg(cfqd); - cic = cfq_cic_lookup(cfqd, ioc); - /* cic always exists here */ + rcu_read_lock(); + + blkcg = bio_blkcg(bio); + cfqg = cfq_lookup_create_cfqg(cfqd, blkcg); cfqq = cic_to_cfqq(cic, is_sync); /* @@ -2870,6 +3197,7 @@ retry: cfqq = new_cfqq; new_cfqq = NULL; } else if (gfp_mask & __GFP_WAIT) { + rcu_read_unlock(); spin_unlock_irq(cfqd->queue->queue_lock); new_cfqq = kmem_cache_alloc_node(cfq_pool, gfp_mask | __GFP_ZERO, @@ -2885,7 +3213,7 @@ retry: if (cfqq) { cfq_init_cfqq(cfqd, cfqq, current->pid, is_sync); - cfq_init_prio_data(cfqq, ioc); + cfq_init_prio_data(cfqq, cic); cfq_link_cfqq_cfqg(cfqq, cfqg); cfq_log_cfqq(cfqd, cfqq, "alloced"); } else @@ -2895,6 +3223,7 @@ retry: if (new_cfqq) kmem_cache_free(cfq_pool, new_cfqq); + rcu_read_unlock(); return cfqq; } @@ -2904,6 +3233,9 @@ cfq_async_queue_prio(struct cfq_data *cfqd, int ioprio_class, int ioprio) switch (ioprio_class) { case IOPRIO_CLASS_RT: return &cfqd->async_cfqq[0][ioprio]; + case IOPRIO_CLASS_NONE: + ioprio = IOPRIO_NORM; + /* fall through */ case IOPRIO_CLASS_BE: return &cfqd->async_cfqq[1][ioprio]; case IOPRIO_CLASS_IDLE: @@ -2914,11 +3246,11 @@ cfq_async_queue_prio(struct cfq_data *cfqd, int ioprio_class, int ioprio) } static struct cfq_queue * -cfq_get_queue(struct cfq_data *cfqd, bool is_sync, struct io_context *ioc, - gfp_t gfp_mask) +cfq_get_queue(struct cfq_data *cfqd, bool is_sync, struct cfq_io_cq *cic, + struct bio *bio, gfp_t gfp_mask) { - const int ioprio = task_ioprio(ioc); - const int ioprio_class = task_ioprio_class(ioc); + const int ioprio_class = IOPRIO_PRIO_CLASS(cic->ioprio); + const int ioprio = IOPRIO_PRIO_DATA(cic->ioprio); struct cfq_queue **async_cfqq = NULL; struct cfq_queue *cfqq = NULL; @@ -2928,7 +3260,7 @@ cfq_get_queue(struct cfq_data *cfqd, bool is_sync, struct io_context *ioc, } if (!cfqq) - cfqq = cfq_find_alloc_queue(cfqd, is_sync, ioc, gfp_mask); + cfqq = cfq_find_alloc_queue(cfqd, is_sync, cic, bio, gfp_mask); /* * pin the queue now that it's allocated, scheduler exit will prune it @@ -3010,7 +3342,7 @@ cfq_update_idle_window(struct cfq_data *cfqd, struct cfq_queue *cfqq, if (cfqq->next_rq && (cfqq->next_rq->cmd_flags & REQ_NOIDLE)) enable_idle = 0; - else if (!atomic_read(&cic->icq.ioc->nr_tasks) || + else if (!atomic_read(&cic->icq.ioc->active_ref) || !cfqd->cfq_slice_idle || (!cfq_cfqq_deep(cfqq) && CFQQ_SEEKY(cfqq))) enable_idle = 0; @@ -3174,8 +3506,7 @@ cfq_rq_enqueued(struct cfq_data *cfqd, struct cfq_queue *cfqq, cfq_clear_cfqq_wait_request(cfqq); __blk_run_queue(cfqd->queue); } else { - cfq_blkiocg_update_idle_time_stats( - &cfqq->cfqg->blkg); + cfqg_stats_update_idle_time(cfqq->cfqg); cfq_mark_cfqq_must_dispatch(cfqq); } } @@ -3197,14 +3528,13 @@ static void cfq_insert_request(struct request_queue *q, struct request *rq) struct cfq_queue *cfqq = RQ_CFQQ(rq); cfq_log_cfqq(cfqd, cfqq, "insert_request"); - cfq_init_prio_data(cfqq, RQ_CIC(rq)->icq.ioc); + cfq_init_prio_data(cfqq, RQ_CIC(rq)); rq_set_fifo_time(rq, jiffies + cfqd->cfq_fifo_expire[rq_is_sync(rq)]); list_add_tail(&rq->queuelist, &cfqq->fifo); cfq_add_rq_rb(rq); - cfq_blkiocg_update_io_add_stats(&(RQ_CFQG(rq))->blkg, - &cfqd->serving_group->blkg, rq_data_dir(rq), - rq_is_sync(rq)); + cfqg_stats_update_io_add(RQ_CFQG(rq), cfqd->serving_group, + rq->cmd_flags); cfq_rq_enqueued(cfqd, cfqq, rq); } @@ -3300,9 +3630,8 @@ static void cfq_completed_request(struct request_queue *q, struct request *rq) cfqd->rq_in_driver--; cfqq->dispatched--; (RQ_CFQG(rq))->dispatched--; - cfq_blkiocg_update_completion_stats(&cfqq->cfqg->blkg, - rq_start_time_ns(rq), rq_io_start_time_ns(rq), - rq_data_dir(rq), rq_is_sync(rq)); + cfqg_stats_update_completion(cfqq->cfqg, rq_start_time_ns(rq), + rq_io_start_time_ns(rq), rq->cmd_flags); cfqd->rq_in_flight[cfq_cfqq_sync(cfqq)]--; @@ -3399,7 +3728,7 @@ static int cfq_may_queue(struct request_queue *q, int rw) cfqq = cic_to_cfqq(cic, rw_is_sync(rw)); if (cfqq) { - cfq_init_prio_data(cfqq, cic->icq.ioc); + cfq_init_prio_data(cfqq, cic); return __cfq_may_queue(cfqq); } @@ -3421,7 +3750,7 @@ static void cfq_put_request(struct request *rq) cfqq->allocated[rw]--; /* Put down rq reference on cfqg */ - cfq_put_cfqg(RQ_CFQG(rq)); + cfqg_put(RQ_CFQG(rq)); rq->elv.priv[0] = NULL; rq->elv.priv[1] = NULL; @@ -3465,32 +3794,25 @@ split_cfqq(struct cfq_io_cq *cic, struct cfq_queue *cfqq) * Allocate cfq data structures associated with this request. */ static int -cfq_set_request(struct request_queue *q, struct request *rq, gfp_t gfp_mask) +cfq_set_request(struct request_queue *q, struct request *rq, struct bio *bio, + gfp_t gfp_mask) { struct cfq_data *cfqd = q->elevator->elevator_data; struct cfq_io_cq *cic = icq_to_cic(rq->elv.icq); const int rw = rq_data_dir(rq); const bool is_sync = rq_is_sync(rq); struct cfq_queue *cfqq; - unsigned int changed; might_sleep_if(gfp_mask & __GFP_WAIT); spin_lock_irq(q->queue_lock); - /* handle changed notifications */ - changed = icq_get_changed(&cic->icq); - if (unlikely(changed & ICQ_IOPRIO_CHANGED)) - changed_ioprio(cic); -#ifdef CONFIG_CFQ_GROUP_IOSCHED - if (unlikely(changed & ICQ_CGROUP_CHANGED)) - changed_cgroup(cic); -#endif - + check_ioprio_changed(cic, bio); + check_blkcg_changed(cic, bio); new_queue: cfqq = cic_to_cfqq(cic, is_sync); if (!cfqq || cfqq == &cfqd->oom_cfqq) { - cfqq = cfq_get_queue(cfqd, is_sync, cic->icq.ioc, gfp_mask); + cfqq = cfq_get_queue(cfqd, is_sync, cic, bio, gfp_mask); cic_set_cfqq(cic, cfqq, is_sync); } else { /* @@ -3516,8 +3838,9 @@ new_queue: cfqq->allocated[rw]++; cfqq->ref++; + cfqg_get(cfqq->cfqg); rq->elv.priv[0] = cfqq; - rq->elv.priv[1] = cfq_ref_get_cfqg(cfqq->cfqg); + rq->elv.priv[1] = cfqq->cfqg; spin_unlock_irq(q->queue_lock); return 0; } @@ -3614,7 +3937,6 @@ static void cfq_exit_queue(struct elevator_queue *e) { struct cfq_data *cfqd = e->elevator_data; struct request_queue *q = cfqd->queue; - bool wait = false; cfq_shutdown_timer_wq(cfqd); @@ -3624,89 +3946,52 @@ static void cfq_exit_queue(struct elevator_queue *e) __cfq_slice_expired(cfqd, cfqd->active_queue, 0); cfq_put_async_queues(cfqd); - cfq_release_cfq_groups(cfqd); - - /* - * If there are groups which we could not unlink from blkcg list, - * wait for a rcu period for them to be freed. - */ - if (cfqd->nr_blkcg_linked_grps) - wait = true; spin_unlock_irq(q->queue_lock); cfq_shutdown_timer_wq(cfqd); - /* - * Wait for cfqg->blkg->key accessors to exit their grace periods. - * Do this wait only if there are other unlinked groups out - * there. This can happen if cgroup deletion path claimed the - * responsibility of cleaning up a group before queue cleanup code - * get to the group. - * - * Do not call synchronize_rcu() unconditionally as there are drivers - * which create/delete request queue hundreds of times during scan/boot - * and synchronize_rcu() can take significant time and slow down boot. - */ - if (wait) - synchronize_rcu(); - -#ifdef CONFIG_CFQ_GROUP_IOSCHED - /* Free up per cpu stats for root group */ - free_percpu(cfqd->root_group.blkg.stats_cpu); +#ifndef CONFIG_CFQ_GROUP_IOSCHED + kfree(cfqd->root_group); #endif + blkcg_deactivate_policy(q, &blkcg_policy_cfq); kfree(cfqd); } -static void *cfq_init_queue(struct request_queue *q) +static int cfq_init_queue(struct request_queue *q) { struct cfq_data *cfqd; - int i, j; - struct cfq_group *cfqg; - struct cfq_rb_root *st; + struct blkcg_gq *blkg __maybe_unused; + int i, ret; cfqd = kmalloc_node(sizeof(*cfqd), GFP_KERNEL | __GFP_ZERO, q->node); if (!cfqd) - return NULL; + return -ENOMEM; + + cfqd->queue = q; + q->elevator->elevator_data = cfqd; /* Init root service tree */ cfqd->grp_service_tree = CFQ_RB_ROOT; - /* Init root group */ - cfqg = &cfqd->root_group; - for_each_cfqg_st(cfqg, i, j, st) - *st = CFQ_RB_ROOT; - RB_CLEAR_NODE(&cfqg->rb_node); - - /* Give preference to root group over other groups */ - cfqg->weight = 2*BLKIO_WEIGHT_DEFAULT; - + /* Init root group and prefer root group over other groups by default */ #ifdef CONFIG_CFQ_GROUP_IOSCHED - /* - * Set root group reference to 2. One reference will be dropped when - * all groups on cfqd->cfqg_list are being deleted during queue exit. - * Other reference will remain there as we don't want to delete this - * group as it is statically allocated and gets destroyed when - * throtl_data goes away. - */ - cfqg->ref = 2; - - if (blkio_alloc_blkg_stats(&cfqg->blkg)) { - kfree(cfqg); - kfree(cfqd); - return NULL; - } - - rcu_read_lock(); + ret = blkcg_activate_policy(q, &blkcg_policy_cfq); + if (ret) + goto out_free; - cfq_blkiocg_add_blkio_group(&blkio_root_cgroup, &cfqg->blkg, - (void *)cfqd, 0); - rcu_read_unlock(); - cfqd->nr_blkcg_linked_grps++; + cfqd->root_group = blkg_to_cfqg(q->root_blkg); +#else + ret = -ENOMEM; + cfqd->root_group = kzalloc_node(sizeof(*cfqd->root_group), + GFP_KERNEL, cfqd->queue->node); + if (!cfqd->root_group) + goto out_free; - /* Add group on cfqd->cfqg_list */ - hlist_add_head(&cfqg->cfqd_node, &cfqd->cfqg_list); + cfq_init_cfqg_base(cfqd->root_group); #endif + cfqd->root_group->weight = 2 * CFQ_WEIGHT_DEFAULT; + /* * Not strictly needed (since RB_ROOT just clears the node and we * zeroed cfqd on alloc), but better be safe in case someone decides @@ -3718,13 +4003,17 @@ static void *cfq_init_queue(struct request_queue *q) /* * Our fallback cfqq if cfq_find_alloc_queue() runs into OOM issues. * Grab a permanent reference to it, so that the normal code flow - * will not attempt to free it. + * will not attempt to free it. oom_cfqq is linked to root_group + * but shouldn't hold a reference as it'll never be unlinked. Lose + * the reference from linking right away. */ cfq_init_cfqq(cfqd, &cfqd->oom_cfqq, 1, 0); cfqd->oom_cfqq.ref++; - cfq_link_cfqq_cfqg(&cfqd->oom_cfqq, &cfqd->root_group); - cfqd->queue = q; + spin_lock_irq(q->queue_lock); + cfq_link_cfqq_cfqg(&cfqd->oom_cfqq, cfqd->root_group); + cfqg_put(cfqd->root_group); + spin_unlock_irq(q->queue_lock); init_timer(&cfqd->idle_slice_timer); cfqd->idle_slice_timer.function = cfq_idle_slice_timer; @@ -3750,7 +4039,11 @@ static void *cfq_init_queue(struct request_queue *q) * second, in order to have larger depth for async operations. */ cfqd->last_delayed_sync = jiffies - HZ; - return cfqd; + return 0; + +out_free: + kfree(cfqd); + return ret; } /* @@ -3877,15 +4170,13 @@ static struct elevator_type iosched_cfq = { }; #ifdef CONFIG_CFQ_GROUP_IOSCHED -static struct blkio_policy_type blkio_policy_cfq = { - .ops = { - .blkio_unlink_group_fn = cfq_unlink_blkio_group, - .blkio_update_group_weight_fn = cfq_update_blkio_group_weight, - }, - .plid = BLKIO_POLICY_PROP, +static struct blkcg_policy blkcg_policy_cfq = { + .pd_size = sizeof(struct cfq_group), + .cftypes = cfq_blkcg_files, + + .pd_init_fn = cfq_pd_init, + .pd_reset_stats_fn = cfq_pd_reset_stats, }; -#else -static struct blkio_policy_type blkio_policy_cfq; #endif static int __init cfq_init(void) @@ -3906,24 +4197,31 @@ static int __init cfq_init(void) #else cfq_group_idle = 0; #endif + + ret = blkcg_policy_register(&blkcg_policy_cfq); + if (ret) + return ret; + cfq_pool = KMEM_CACHE(cfq_queue, 0); if (!cfq_pool) - return -ENOMEM; + goto err_pol_unreg; ret = elv_register(&iosched_cfq); - if (ret) { - kmem_cache_destroy(cfq_pool); - return ret; - } - - blkio_policy_register(&blkio_policy_cfq); + if (ret) + goto err_free_pool; return 0; + +err_free_pool: + kmem_cache_destroy(cfq_pool); +err_pol_unreg: + blkcg_policy_unregister(&blkcg_policy_cfq); + return ret; } static void __exit cfq_exit(void) { - blkio_policy_unregister(&blkio_policy_cfq); + blkcg_policy_unregister(&blkcg_policy_cfq); elv_unregister(&iosched_cfq); kmem_cache_destroy(cfq_pool); } |