| /* |
| * 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/ioprio.h> |
| #include <linux/seq_file.h> |
| #include <linux/kdev_t.h> |
| #include <linux/module.h> |
| #include <linux/err.h> |
| #include <linux/blkdev.h> |
| #include <linux/slab.h> |
| #include "blk-cgroup.h" |
| #include <linux/genhd.h> |
| |
| #define MAX_KEY_LEN 100 |
| |
| static DEFINE_SPINLOCK(blkio_list_lock); |
| static LIST_HEAD(blkio_list); |
| |
| struct blkio_cgroup blkio_root_cgroup = { .weight = 2*BLKIO_WEIGHT_DEFAULT }; |
| EXPORT_SYMBOL_GPL(blkio_root_cgroup); |
| |
| static struct cgroup_subsys_state *blkiocg_create(struct cgroup_subsys *, |
| struct cgroup *); |
| static int blkiocg_can_attach(struct cgroup_subsys *, struct cgroup *, |
| struct cgroup_taskset *); |
| static void blkiocg_attach(struct cgroup_subsys *, struct cgroup *, |
| struct cgroup_taskset *); |
| static void blkiocg_destroy(struct cgroup_subsys *, struct cgroup *); |
| static int blkiocg_populate(struct cgroup_subsys *, struct cgroup *); |
| |
| /* for encoding cft->private value on file */ |
| #define BLKIOFILE_PRIVATE(x, val) (((x) << 16) | (val)) |
| /* What policy owns the file, proportional or throttle */ |
| #define BLKIOFILE_POLICY(val) (((val) >> 16) & 0xffff) |
| #define BLKIOFILE_ATTR(val) ((val) & 0xffff) |
| |
| struct cgroup_subsys blkio_subsys = { |
| .name = "blkio", |
| .create = blkiocg_create, |
| .can_attach = blkiocg_can_attach, |
| .attach = blkiocg_attach, |
| .destroy = blkiocg_destroy, |
| .populate = blkiocg_populate, |
| #ifdef CONFIG_BLK_CGROUP |
| /* note: blkio_subsys_id is otherwise defined in blk-cgroup.h */ |
| .subsys_id = blkio_subsys_id, |
| #endif |
| .use_id = 1, |
| .module = THIS_MODULE, |
| }; |
| EXPORT_SYMBOL_GPL(blkio_subsys); |
| |
| static inline void blkio_policy_insert_node(struct blkio_cgroup *blkcg, |
| struct blkio_policy_node *pn) |
| { |
| list_add(&pn->node, &blkcg->policy_list); |
| } |
| |
| static inline bool cftype_blkg_same_policy(struct cftype *cft, |
| struct blkio_group *blkg) |
| { |
| enum blkio_policy_id plid = BLKIOFILE_POLICY(cft->private); |
| |
| if (blkg->plid == plid) |
| return 1; |
| |
| return 0; |
| } |
| |
| /* Determines if policy node matches cgroup file being accessed */ |
| static inline bool pn_matches_cftype(struct cftype *cft, |
| struct blkio_policy_node *pn) |
| { |
| enum blkio_policy_id plid = BLKIOFILE_POLICY(cft->private); |
| int fileid = BLKIOFILE_ATTR(cft->private); |
| |
| return (plid == pn->plid && fileid == pn->fileid); |
| } |
| |
| /* Must be called with blkcg->lock held */ |
| static inline void blkio_policy_delete_node(struct blkio_policy_node *pn) |
| { |
| list_del(&pn->node); |
| } |
| |
| /* Must be called with blkcg->lock held */ |
| static struct blkio_policy_node * |
| blkio_policy_search_node(const struct blkio_cgroup *blkcg, dev_t dev, |
| enum blkio_policy_id plid, int fileid) |
| { |
| struct blkio_policy_node *pn; |
| |
| list_for_each_entry(pn, &blkcg->policy_list, node) { |
| if (pn->dev == dev && pn->plid == plid && pn->fileid == fileid) |
| return pn; |
| } |
| |
| return NULL; |
| } |
| |
| struct blkio_cgroup *cgroup_to_blkio_cgroup(struct cgroup *cgroup) |
| { |
| return container_of(cgroup_subsys_state(cgroup, blkio_subsys_id), |
| struct blkio_cgroup, css); |
| } |
| EXPORT_SYMBOL_GPL(cgroup_to_blkio_cgroup); |
| |
| struct blkio_cgroup *task_blkio_cgroup(struct task_struct *tsk) |
| { |
| return container_of(task_subsys_state(tsk, blkio_subsys_id), |
| struct blkio_cgroup, css); |
| } |
| EXPORT_SYMBOL_GPL(task_blkio_cgroup); |
| |
| static inline void |
| blkio_update_group_weight(struct blkio_group *blkg, unsigned int weight) |
| { |
| struct blkio_policy_type *blkiop; |
| |
| list_for_each_entry(blkiop, &blkio_list, list) { |
| /* If this policy does not own the blkg, do not send updates */ |
| if (blkiop->plid != blkg->plid) |
| continue; |
| if (blkiop->ops.blkio_update_group_weight_fn) |
| blkiop->ops.blkio_update_group_weight_fn(blkg->key, |
| blkg, weight); |
| } |
| } |
| |
| static inline void blkio_update_group_bps(struct blkio_group *blkg, u64 bps, |
| int fileid) |
| { |
| struct blkio_policy_type *blkiop; |
| |
| list_for_each_entry(blkiop, &blkio_list, list) { |
| |
| /* If this policy does not own the blkg, do not send updates */ |
| if (blkiop->plid != blkg->plid) |
| continue; |
| |
| if (fileid == BLKIO_THROTL_read_bps_device |
| && blkiop->ops.blkio_update_group_read_bps_fn) |
| blkiop->ops.blkio_update_group_read_bps_fn(blkg->key, |
| blkg, bps); |
| |
| if (fileid == BLKIO_THROTL_write_bps_device |
| && blkiop->ops.blkio_update_group_write_bps_fn) |
| blkiop->ops.blkio_update_group_write_bps_fn(blkg->key, |
| blkg, bps); |
| } |
| } |
| |
| static inline void blkio_update_group_iops(struct blkio_group *blkg, |
| unsigned int iops, int fileid) |
| { |
| struct blkio_policy_type *blkiop; |
| |
| list_for_each_entry(blkiop, &blkio_list, list) { |
| |
| /* If this policy does not own the blkg, do not send updates */ |
| if (blkiop->plid != blkg->plid) |
| continue; |
| |
| if (fileid == BLKIO_THROTL_read_iops_device |
| && blkiop->ops.blkio_update_group_read_iops_fn) |
| blkiop->ops.blkio_update_group_read_iops_fn(blkg->key, |
| blkg, iops); |
| |
| if (fileid == BLKIO_THROTL_write_iops_device |
| && blkiop->ops.blkio_update_group_write_iops_fn) |
| blkiop->ops.blkio_update_group_write_iops_fn(blkg->key, |
| blkg,iops); |
| } |
| } |
| |
| /* |
| * Add to the appropriate stat variable depending on the request type. |
| * This should be called with the blkg->stats_lock held. |
| */ |
| static void blkio_add_stat(uint64_t *stat, uint64_t add, bool direction, |
| bool sync) |
| { |
| if (direction) |
| stat[BLKIO_STAT_WRITE] += add; |
| else |
| stat[BLKIO_STAT_READ] += add; |
| if (sync) |
| stat[BLKIO_STAT_SYNC] += add; |
| else |
| stat[BLKIO_STAT_ASYNC] += add; |
| } |
| |
| /* |
| * Decrements the appropriate stat variable if non-zero depending on the |
| * request type. Panics on value being zero. |
| * This should be called with the blkg->stats_lock held. |
| */ |
| static void blkio_check_and_dec_stat(uint64_t *stat, bool direction, bool sync) |
| { |
| if (direction) { |
| BUG_ON(stat[BLKIO_STAT_WRITE] == 0); |
| stat[BLKIO_STAT_WRITE]--; |
| } else { |
| BUG_ON(stat[BLKIO_STAT_READ] == 0); |
| stat[BLKIO_STAT_READ]--; |
| } |
| if (sync) { |
| BUG_ON(stat[BLKIO_STAT_SYNC] == 0); |
| stat[BLKIO_STAT_SYNC]--; |
| } else { |
| BUG_ON(stat[BLKIO_STAT_ASYNC] == 0); |
| stat[BLKIO_STAT_ASYNC]--; |
| } |
| } |
| |
| #ifdef CONFIG_DEBUG_BLK_CGROUP |
| /* This should be called with the blkg->stats_lock held. */ |
| static void blkio_set_start_group_wait_time(struct blkio_group *blkg, |
| struct blkio_group *curr_blkg) |
| { |
| if (blkio_blkg_waiting(&blkg->stats)) |
| return; |
| if (blkg == curr_blkg) |
| return; |
| blkg->stats.start_group_wait_time = sched_clock(); |
| blkio_mark_blkg_waiting(&blkg->stats); |
| } |
| |
| /* This should be called with the blkg->stats_lock held. */ |
| static void blkio_update_group_wait_time(struct blkio_group_stats *stats) |
| { |
| unsigned long long now; |
| |
| if (!blkio_blkg_waiting(stats)) |
| return; |
| |
| now = sched_clock(); |
| if (time_after64(now, stats->start_group_wait_time)) |
| stats->group_wait_time += now - stats->start_group_wait_time; |
| blkio_clear_blkg_waiting(stats); |
| } |
| |
| /* This should be called with the blkg->stats_lock held. */ |
| static void blkio_end_empty_time(struct blkio_group_stats *stats) |
| { |
| unsigned long long now; |
| |
| if (!blkio_blkg_empty(stats)) |
| return; |
| |
| now = sched_clock(); |
| if (time_after64(now, stats->start_empty_time)) |
| stats->empty_time += now - stats->start_empty_time; |
| blkio_clear_blkg_empty(stats); |
| } |
| |
| void blkiocg_update_set_idle_time_stats(struct blkio_group *blkg) |
| { |
| unsigned long flags; |
| |
| spin_lock_irqsave(&blkg->stats_lock, flags); |
| BUG_ON(blkio_blkg_idling(&blkg->stats)); |
| blkg->stats.start_idle_time = sched_clock(); |
| blkio_mark_blkg_idling(&blkg->stats); |
| spin_unlock_irqrestore(&blkg->stats_lock, flags); |
| } |
| EXPORT_SYMBOL_GPL(blkiocg_update_set_idle_time_stats); |
| |
| void blkiocg_update_idle_time_stats(struct blkio_group *blkg) |
| { |
| unsigned long flags; |
| unsigned long long now; |
| struct blkio_group_stats *stats; |
| |
| spin_lock_irqsave(&blkg->stats_lock, flags); |
| stats = &blkg->stats; |
| if (blkio_blkg_idling(stats)) { |
| now = sched_clock(); |
| if (time_after64(now, stats->start_idle_time)) |
| stats->idle_time += now - stats->start_idle_time; |
| blkio_clear_blkg_idling(stats); |
| } |
| spin_unlock_irqrestore(&blkg->stats_lock, flags); |
| } |
| EXPORT_SYMBOL_GPL(blkiocg_update_idle_time_stats); |
| |
| void blkiocg_update_avg_queue_size_stats(struct blkio_group *blkg) |
| { |
| unsigned long flags; |
| struct blkio_group_stats *stats; |
| |
| spin_lock_irqsave(&blkg->stats_lock, flags); |
| stats = &blkg->stats; |
| stats->avg_queue_size_sum += |
| stats->stat_arr[BLKIO_STAT_QUEUED][BLKIO_STAT_READ] + |
| stats->stat_arr[BLKIO_STAT_QUEUED][BLKIO_STAT_WRITE]; |
| stats->avg_queue_size_samples++; |
| blkio_update_group_wait_time(stats); |
| spin_unlock_irqrestore(&blkg->stats_lock, flags); |
| } |
| EXPORT_SYMBOL_GPL(blkiocg_update_avg_queue_size_stats); |
| |
| void blkiocg_set_start_empty_time(struct blkio_group *blkg) |
| { |
| unsigned long flags; |
| struct blkio_group_stats *stats; |
| |
| spin_lock_irqsave(&blkg->stats_lock, flags); |
| stats = &blkg->stats; |
| |
| if (stats->stat_arr[BLKIO_STAT_QUEUED][BLKIO_STAT_READ] || |
| stats->stat_arr[BLKIO_STAT_QUEUED][BLKIO_STAT_WRITE]) { |
| spin_unlock_irqrestore(&blkg->stats_lock, flags); |
| 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(blkio_blkg_empty(stats)) { |
| spin_unlock_irqrestore(&blkg->stats_lock, flags); |
| return; |
| } |
| |
| stats->start_empty_time = sched_clock(); |
| blkio_mark_blkg_empty(stats); |
| spin_unlock_irqrestore(&blkg->stats_lock, flags); |
| } |
| EXPORT_SYMBOL_GPL(blkiocg_set_start_empty_time); |
| |
| void blkiocg_update_dequeue_stats(struct blkio_group *blkg, |
| unsigned long dequeue) |
| { |
| blkg->stats.dequeue += dequeue; |
| } |
| EXPORT_SYMBOL_GPL(blkiocg_update_dequeue_stats); |
| #else |
| static inline void blkio_set_start_group_wait_time(struct blkio_group *blkg, |
| struct blkio_group *curr_blkg) {} |
| static inline void blkio_end_empty_time(struct blkio_group_stats *stats) {} |
| #endif |
| |
| void blkiocg_update_io_add_stats(struct blkio_group *blkg, |
| struct blkio_group *curr_blkg, bool direction, |
| bool sync) |
| { |
| unsigned long flags; |
| |
| spin_lock_irqsave(&blkg->stats_lock, flags); |
| blkio_add_stat(blkg->stats.stat_arr[BLKIO_STAT_QUEUED], 1, direction, |
| sync); |
| blkio_end_empty_time(&blkg->stats); |
| blkio_set_start_group_wait_time(blkg, curr_blkg); |
| spin_unlock_irqrestore(&blkg->stats_lock, flags); |
| } |
| EXPORT_SYMBOL_GPL(blkiocg_update_io_add_stats); |
| |
| void blkiocg_update_io_remove_stats(struct blkio_group *blkg, |
| bool direction, bool sync) |
| { |
| unsigned long flags; |
| |
| spin_lock_irqsave(&blkg->stats_lock, flags); |
| blkio_check_and_dec_stat(blkg->stats.stat_arr[BLKIO_STAT_QUEUED], |
| direction, sync); |
| spin_unlock_irqrestore(&blkg->stats_lock, flags); |
| } |
| EXPORT_SYMBOL_GPL(blkiocg_update_io_remove_stats); |
| |
| void blkiocg_update_timeslice_used(struct blkio_group *blkg, unsigned long time, |
| unsigned long unaccounted_time) |
| { |
| unsigned long flags; |
| |
| spin_lock_irqsave(&blkg->stats_lock, flags); |
| blkg->stats.time += time; |
| #ifdef CONFIG_DEBUG_BLK_CGROUP |
| blkg->stats.unaccounted_time += unaccounted_time; |
| #endif |
| spin_unlock_irqrestore(&blkg->stats_lock, flags); |
| } |
| EXPORT_SYMBOL_GPL(blkiocg_update_timeslice_used); |
| |
| /* |
| * should be called under rcu read lock or queue lock to make sure blkg pointer |
| * is valid. |
| */ |
| void blkiocg_update_dispatch_stats(struct blkio_group *blkg, |
| uint64_t bytes, bool direction, bool sync) |
| { |
| struct blkio_group_stats_cpu *stats_cpu; |
| unsigned long flags; |
| |
| /* |
| * Disabling interrupts to provide mutual exclusion between two |
| * writes on same cpu. It probably is not needed for 64bit. Not |
| * optimizing that case yet. |
| */ |
| local_irq_save(flags); |
| |
| stats_cpu = this_cpu_ptr(blkg->stats_cpu); |
| |
| u64_stats_update_begin(&stats_cpu->syncp); |
| stats_cpu->sectors += bytes >> 9; |
| blkio_add_stat(stats_cpu->stat_arr_cpu[BLKIO_STAT_CPU_SERVICED], |
| 1, direction, sync); |
| blkio_add_stat(stats_cpu->stat_arr_cpu[BLKIO_STAT_CPU_SERVICE_BYTES], |
| bytes, direction, sync); |
| u64_stats_update_end(&stats_cpu->syncp); |
| local_irq_restore(flags); |
| } |
| EXPORT_SYMBOL_GPL(blkiocg_update_dispatch_stats); |
| |
| void blkiocg_update_completion_stats(struct blkio_group *blkg, |
| uint64_t start_time, uint64_t io_start_time, bool direction, bool sync) |
| { |
| struct blkio_group_stats *stats; |
| unsigned long flags; |
| unsigned long long now = sched_clock(); |
| |
| spin_lock_irqsave(&blkg->stats_lock, flags); |
| stats = &blkg->stats; |
| if (time_after64(now, io_start_time)) |
| blkio_add_stat(stats->stat_arr[BLKIO_STAT_SERVICE_TIME], |
| now - io_start_time, direction, sync); |
| if (time_after64(io_start_time, start_time)) |
| blkio_add_stat(stats->stat_arr[BLKIO_STAT_WAIT_TIME], |
| io_start_time - start_time, direction, sync); |
| spin_unlock_irqrestore(&blkg->stats_lock, flags); |
| } |
| EXPORT_SYMBOL_GPL(blkiocg_update_completion_stats); |
| |
| /* Merged stats are per cpu. */ |
| void blkiocg_update_io_merged_stats(struct blkio_group *blkg, bool direction, |
| bool sync) |
| { |
| struct blkio_group_stats_cpu *stats_cpu; |
| unsigned long flags; |
| |
| /* |
| * Disabling interrupts to provide mutual exclusion between two |
| * writes on same cpu. It probably is not needed for 64bit. Not |
| * optimizing that case yet. |
| */ |
| local_irq_save(flags); |
| |
| stats_cpu = this_cpu_ptr(blkg->stats_cpu); |
| |
| u64_stats_update_begin(&stats_cpu->syncp); |
| blkio_add_stat(stats_cpu->stat_arr_cpu[BLKIO_STAT_CPU_MERGED], 1, |
| direction, sync); |
| u64_stats_update_end(&stats_cpu->syncp); |
| local_irq_restore(flags); |
| } |
| EXPORT_SYMBOL_GPL(blkiocg_update_io_merged_stats); |
| |
| /* |
| * This function allocates the per cpu stats for blkio_group. Should be called |
| * from sleepable context as alloc_per_cpu() requires that. |
| */ |
| int blkio_alloc_blkg_stats(struct blkio_group *blkg) |
| { |
| /* Allocate memory for per cpu stats */ |
| blkg->stats_cpu = alloc_percpu(struct blkio_group_stats_cpu); |
| if (!blkg->stats_cpu) |
| return -ENOMEM; |
| return 0; |
| } |
| EXPORT_SYMBOL_GPL(blkio_alloc_blkg_stats); |
| |
| void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg, |
| struct blkio_group *blkg, void *key, dev_t dev, |
| enum blkio_policy_id plid) |
| { |
| unsigned long flags; |
| |
| spin_lock_irqsave(&blkcg->lock, flags); |
| spin_lock_init(&blkg->stats_lock); |
| rcu_assign_pointer(blkg->key, key); |
| blkg->blkcg_id = css_id(&blkcg->css); |
| hlist_add_head_rcu(&blkg->blkcg_node, &blkcg->blkg_list); |
| blkg->plid = plid; |
| spin_unlock_irqrestore(&blkcg->lock, flags); |
| /* Need to take css reference ? */ |
| cgroup_path(blkcg->css.cgroup, blkg->path, sizeof(blkg->path)); |
| blkg->dev = dev; |
| } |
| EXPORT_SYMBOL_GPL(blkiocg_add_blkio_group); |
| |
| static void __blkiocg_del_blkio_group(struct blkio_group *blkg) |
| { |
| hlist_del_init_rcu(&blkg->blkcg_node); |
| blkg->blkcg_id = 0; |
| } |
| |
| /* |
| * returns 0 if blkio_group was still on cgroup list. Otherwise returns 1 |
| * indicating that blk_group was unhashed by the time we got to it. |
| */ |
| int blkiocg_del_blkio_group(struct blkio_group *blkg) |
| { |
| struct blkio_cgroup *blkcg; |
| unsigned long flags; |
| struct cgroup_subsys_state *css; |
| int ret = 1; |
| |
| rcu_read_lock(); |
| css = css_lookup(&blkio_subsys, blkg->blkcg_id); |
| if (css) { |
| blkcg = container_of(css, struct blkio_cgroup, css); |
| spin_lock_irqsave(&blkcg->lock, flags); |
| if (!hlist_unhashed(&blkg->blkcg_node)) { |
| __blkiocg_del_blkio_group(blkg); |
| ret = 0; |
| } |
| spin_unlock_irqrestore(&blkcg->lock, flags); |
| } |
| |
| rcu_read_unlock(); |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(blkiocg_del_blkio_group); |
| |
| /* called under rcu_read_lock(). */ |
| struct blkio_group *blkiocg_lookup_group(struct blkio_cgroup *blkcg, void *key) |
| { |
| struct blkio_group *blkg; |
| struct hlist_node *n; |
| void *__key; |
| |
| hlist_for_each_entry_rcu(blkg, n, &blkcg->blkg_list, blkcg_node) { |
| __key = blkg->key; |
| if (__key == key) |
| return blkg; |
| } |
| |
| return NULL; |
| } |
| EXPORT_SYMBOL_GPL(blkiocg_lookup_group); |
| |
| static void blkio_reset_stats_cpu(struct blkio_group *blkg) |
| { |
| struct blkio_group_stats_cpu *stats_cpu; |
| int i, j, k; |
| /* |
| * Note: On 64 bit arch this should not be an issue. This has the |
| * possibility of returning some inconsistent value on 32bit arch |
| * as 64bit update on 32bit is non atomic. Taking care of this |
| * corner case makes code very complicated, like sending IPIs to |
| * cpus, taking care of stats of offline cpus etc. |
| * |
| * reset stats is anyway more of a debug feature and this sounds a |
| * corner case. So I am not complicating the code yet until and |
| * unless this becomes a real issue. |
| */ |
| for_each_possible_cpu(i) { |
| stats_cpu = per_cpu_ptr(blkg->stats_cpu, i); |
| stats_cpu->sectors = 0; |
| for(j = 0; j < BLKIO_STAT_CPU_NR; j++) |
| for (k = 0; k < BLKIO_STAT_TOTAL; k++) |
| stats_cpu->stat_arr_cpu[j][k] = 0; |
| } |
| } |
| |
| static int |
| blkiocg_reset_stats(struct cgroup *cgroup, struct cftype *cftype, u64 val) |
| { |
| struct blkio_cgroup *blkcg; |
| struct blkio_group *blkg; |
| struct blkio_group_stats *stats; |
| struct hlist_node *n; |
| uint64_t queued[BLKIO_STAT_TOTAL]; |
| int i; |
| #ifdef CONFIG_DEBUG_BLK_CGROUP |
| bool idling, waiting, empty; |
| unsigned long long now = sched_clock(); |
| #endif |
| |
| blkcg = cgroup_to_blkio_cgroup(cgroup); |
| spin_lock_irq(&blkcg->lock); |
| hlist_for_each_entry(blkg, n, &blkcg->blkg_list, blkcg_node) { |
| spin_lock(&blkg->stats_lock); |
| stats = &blkg->stats; |
| #ifdef CONFIG_DEBUG_BLK_CGROUP |
| idling = blkio_blkg_idling(stats); |
| waiting = blkio_blkg_waiting(stats); |
| empty = blkio_blkg_empty(stats); |
| #endif |
| for (i = 0; i < BLKIO_STAT_TOTAL; i++) |
| queued[i] = stats->stat_arr[BLKIO_STAT_QUEUED][i]; |
| memset(stats, 0, sizeof(struct blkio_group_stats)); |
| for (i = 0; i < BLKIO_STAT_TOTAL; i++) |
| stats->stat_arr[BLKIO_STAT_QUEUED][i] = queued[i]; |
| #ifdef CONFIG_DEBUG_BLK_CGROUP |
| if (idling) { |
| blkio_mark_blkg_idling(stats); |
| stats->start_idle_time = now; |
| } |
| if (waiting) { |
| blkio_mark_blkg_waiting(stats); |
| stats->start_group_wait_time = now; |
| } |
| if (empty) { |
| blkio_mark_blkg_empty(stats); |
| stats->start_empty_time = now; |
| } |
| #endif |
| spin_unlock(&blkg->stats_lock); |
| |
| /* Reset Per cpu stats which don't take blkg->stats_lock */ |
| blkio_reset_stats_cpu(blkg); |
| } |
| |
| spin_unlock_irq(&blkcg->lock); |
| return 0; |
| } |
| |
| static void blkio_get_key_name(enum stat_sub_type type, dev_t dev, char *str, |
| int chars_left, bool diskname_only) |
| { |
| snprintf(str, chars_left, "%d:%d", MAJOR(dev), MINOR(dev)); |
| chars_left -= strlen(str); |
| if (chars_left <= 0) { |
| printk(KERN_WARNING |
| "Possibly incorrect cgroup stat display format"); |
| return; |
| } |
| if (diskname_only) |
| return; |
| switch (type) { |
| case BLKIO_STAT_READ: |
| strlcat(str, " Read", chars_left); |
| break; |
| case BLKIO_STAT_WRITE: |
| strlcat(str, " Write", chars_left); |
| break; |
| case BLKIO_STAT_SYNC: |
| strlcat(str, " Sync", chars_left); |
| break; |
| case BLKIO_STAT_ASYNC: |
| strlcat(str, " Async", chars_left); |
| break; |
| case BLKIO_STAT_TOTAL: |
| strlcat(str, " Total", chars_left); |
| break; |
| default: |
| strlcat(str, " Invalid", chars_left); |
| } |
| } |
| |
| static uint64_t blkio_fill_stat(char *str, int chars_left, uint64_t val, |
| struct cgroup_map_cb *cb, dev_t dev) |
| { |
| blkio_get_key_name(0, dev, str, chars_left, true); |
| cb->fill(cb, str, val); |
| return val; |
| } |
| |
| |
| static uint64_t blkio_read_stat_cpu(struct blkio_group *blkg, |
| enum stat_type_cpu type, enum stat_sub_type sub_type) |
| { |
| int cpu; |
| struct blkio_group_stats_cpu *stats_cpu; |
| u64 val = 0, tval; |
| |
| for_each_possible_cpu(cpu) { |
| unsigned int start; |
| stats_cpu = per_cpu_ptr(blkg->stats_cpu, cpu); |
| |
| do { |
| start = u64_stats_fetch_begin(&stats_cpu->syncp); |
| if (type == BLKIO_STAT_CPU_SECTORS) |
| tval = stats_cpu->sectors; |
| else |
| tval = stats_cpu->stat_arr_cpu[type][sub_type]; |
| } while(u64_stats_fetch_retry(&stats_cpu->syncp, start)); |
| |
| val += tval; |
| } |
| |
| return val; |
| } |
| |
| static uint64_t blkio_get_stat_cpu(struct blkio_group *blkg, |
| struct cgroup_map_cb *cb, dev_t dev, enum stat_type_cpu type) |
| { |
| uint64_t disk_total, val; |
| char key_str[MAX_KEY_LEN]; |
| enum stat_sub_type sub_type; |
| |
| if (type == BLKIO_STAT_CPU_SECTORS) { |
| val = blkio_read_stat_cpu(blkg, type, 0); |
| return blkio_fill_stat(key_str, MAX_KEY_LEN - 1, val, cb, dev); |
| } |
| |
| for (sub_type = BLKIO_STAT_READ; sub_type < BLKIO_STAT_TOTAL; |
| sub_type++) { |
| blkio_get_key_name(sub_type, dev, key_str, MAX_KEY_LEN, false); |
| val = blkio_read_stat_cpu(blkg, type, sub_type); |
| cb->fill(cb, key_str, val); |
| } |
| |
| disk_total = blkio_read_stat_cpu(blkg, type, BLKIO_STAT_READ) + |
| blkio_read_stat_cpu(blkg, type, BLKIO_STAT_WRITE); |
| |
| blkio_get_key_name(BLKIO_STAT_TOTAL, dev, key_str, MAX_KEY_LEN, false); |
| cb->fill(cb, key_str, disk_total); |
| return disk_total; |
| } |
| |
| /* This should be called with blkg->stats_lock held */ |
| static uint64_t blkio_get_stat(struct blkio_group *blkg, |
| struct cgroup_map_cb *cb, dev_t dev, enum stat_type type) |
| { |
| uint64_t disk_total; |
| char key_str[MAX_KEY_LEN]; |
| enum stat_sub_type sub_type; |
| |
| if (type == BLKIO_STAT_TIME) |
| return blkio_fill_stat(key_str, MAX_KEY_LEN - 1, |
| blkg->stats.time, cb, dev); |
| #ifdef CONFIG_DEBUG_BLK_CGROUP |
| if (type == BLKIO_STAT_UNACCOUNTED_TIME) |
| return blkio_fill_stat(key_str, MAX_KEY_LEN - 1, |
| blkg->stats.unaccounted_time, cb, dev); |
| if (type == BLKIO_STAT_AVG_QUEUE_SIZE) { |
| uint64_t sum = blkg->stats.avg_queue_size_sum; |
| uint64_t samples = blkg->stats.avg_queue_size_samples; |
| if (samples) |
| do_div(sum, samples); |
| else |
| sum = 0; |
| return blkio_fill_stat(key_str, MAX_KEY_LEN - 1, sum, cb, dev); |
| } |
| if (type == BLKIO_STAT_GROUP_WAIT_TIME) |
| return blkio_fill_stat(key_str, MAX_KEY_LEN - 1, |
| blkg->stats.group_wait_time, cb, dev); |
| if (type == BLKIO_STAT_IDLE_TIME) |
| return blkio_fill_stat(key_str, MAX_KEY_LEN - 1, |
| blkg->stats.idle_time, cb, dev); |
| if (type == BLKIO_STAT_EMPTY_TIME) |
| return blkio_fill_stat(key_str, MAX_KEY_LEN - 1, |
| blkg->stats.empty_time, cb, dev); |
| if (type == BLKIO_STAT_DEQUEUE) |
| return blkio_fill_stat(key_str, MAX_KEY_LEN - 1, |
| blkg->stats.dequeue, cb, dev); |
| #endif |
| |
| for (sub_type = BLKIO_STAT_READ; sub_type < BLKIO_STAT_TOTAL; |
| sub_type++) { |
| blkio_get_key_name(sub_type, dev, key_str, MAX_KEY_LEN, false); |
| cb->fill(cb, key_str, blkg->stats.stat_arr[type][sub_type]); |
| } |
| disk_total = blkg->stats.stat_arr[type][BLKIO_STAT_READ] + |
| blkg->stats.stat_arr[type][BLKIO_STAT_WRITE]; |
| blkio_get_key_name(BLKIO_STAT_TOTAL, dev, key_str, MAX_KEY_LEN, false); |
| cb->fill(cb, key_str, disk_total); |
| return disk_total; |
| } |
| |
| static int blkio_policy_parse_and_set(char *buf, |
| struct blkio_policy_node *newpn, enum blkio_policy_id plid, int fileid) |
| { |
| struct gendisk *disk = NULL; |
| char *s[4], *p, *major_s = NULL, *minor_s = NULL; |
| unsigned long major, minor; |
| int i = 0, ret = -EINVAL; |
| int part; |
| dev_t dev; |
| u64 temp; |
| |
| memset(s, 0, sizeof(s)); |
| |
| while ((p = strsep(&buf, " ")) != NULL) { |
| if (!*p) |
| continue; |
| |
| s[i++] = p; |
| |
| /* Prevent from inputing too many things */ |
| if (i == 3) |
| break; |
| } |
| |
| if (i != 2) |
| goto out; |
| |
| p = strsep(&s[0], ":"); |
| if (p != NULL) |
| major_s = p; |
| else |
| goto out; |
| |
| minor_s = s[0]; |
| if (!minor_s) |
| goto out; |
| |
| if (strict_strtoul(major_s, 10, &major)) |
| goto out; |
| |
| if (strict_strtoul(minor_s, 10, &minor)) |
| goto out; |
| |
| dev = MKDEV(major, minor); |
| |
| if (strict_strtoull(s[1], 10, &temp)) |
| goto out; |
| |
| /* For rule removal, do not check for device presence. */ |
| if (temp) { |
| disk = get_gendisk(dev, &part); |
| if (!disk || part) { |
| ret = -ENODEV; |
| goto out; |
| } |
| } |
| |
| newpn->dev = dev; |
| |
| switch (plid) { |
| case BLKIO_POLICY_PROP: |
| if ((temp < BLKIO_WEIGHT_MIN && temp > 0) || |
| temp > BLKIO_WEIGHT_MAX) |
| goto out; |
| |
| newpn->plid = plid; |
| newpn->fileid = fileid; |
| newpn->val.weight = temp; |
| break; |
| case BLKIO_POLICY_THROTL: |
| switch(fileid) { |
| case BLKIO_THROTL_read_bps_device: |
| case BLKIO_THROTL_write_bps_device: |
| newpn->plid = plid; |
| newpn->fileid = fileid; |
| newpn->val.bps = temp; |
| break; |
| case BLKIO_THROTL_read_iops_device: |
| case BLKIO_THROTL_write_iops_device: |
| if (temp > THROTL_IOPS_MAX) |
| goto out; |
| |
| newpn->plid = plid; |
| newpn->fileid = fileid; |
| newpn->val.iops = (unsigned int)temp; |
| break; |
| } |
| break; |
| default: |
| BUG(); |
| } |
| ret = 0; |
| out: |
| put_disk(disk); |
| return ret; |
| } |
| |
| unsigned int blkcg_get_weight(struct blkio_cgroup *blkcg, |
| dev_t dev) |
| { |
| struct blkio_policy_node *pn; |
| unsigned long flags; |
| unsigned int weight; |
| |
| spin_lock_irqsave(&blkcg->lock, flags); |
| |
| pn = blkio_policy_search_node(blkcg, dev, BLKIO_POLICY_PROP, |
| BLKIO_PROP_weight_device); |
| if (pn) |
| weight = pn->val.weight; |
| else |
| weight = blkcg->weight; |
| |
| spin_unlock_irqrestore(&blkcg->lock, flags); |
| |
| return weight; |
| } |
| EXPORT_SYMBOL_GPL(blkcg_get_weight); |
| |
| uint64_t blkcg_get_read_bps(struct blkio_cgroup *blkcg, dev_t dev) |
| { |
| struct blkio_policy_node *pn; |
| unsigned long flags; |
| uint64_t bps = -1; |
| |
| spin_lock_irqsave(&blkcg->lock, flags); |
| pn = blkio_policy_search_node(blkcg, dev, BLKIO_POLICY_THROTL, |
| BLKIO_THROTL_read_bps_device); |
| if (pn) |
| bps = pn->val.bps; |
| spin_unlock_irqrestore(&blkcg->lock, flags); |
| |
| return bps; |
| } |
| |
| uint64_t blkcg_get_write_bps(struct blkio_cgroup *blkcg, dev_t dev) |
| { |
| struct blkio_policy_node *pn; |
| unsigned long flags; |
| uint64_t bps = -1; |
| |
| spin_lock_irqsave(&blkcg->lock, flags); |
| pn = blkio_policy_search_node(blkcg, dev, BLKIO_POLICY_THROTL, |
| BLKIO_THROTL_write_bps_device); |
| if (pn) |
| bps = pn->val.bps; |
| spin_unlock_irqrestore(&blkcg->lock, flags); |
| |
| return bps; |
| } |
| |
| unsigned int blkcg_get_read_iops(struct blkio_cgroup *blkcg, dev_t dev) |
| { |
| struct blkio_policy_node *pn; |
| unsigned long flags; |
| unsigned int iops = -1; |
| |
| spin_lock_irqsave(&blkcg->lock, flags); |
| pn = blkio_policy_search_node(blkcg, dev, BLKIO_POLICY_THROTL, |
| BLKIO_THROTL_read_iops_device); |
| if (pn) |
| iops = pn->val.iops; |
| spin_unlock_irqrestore(&blkcg->lock, flags); |
| |
| return iops; |
| } |
| |
| unsigned int blkcg_get_write_iops(struct blkio_cgroup *blkcg, dev_t dev) |
| { |
| struct blkio_policy_node *pn; |
| unsigned long flags; |
| unsigned int iops = -1; |
| |
| spin_lock_irqsave(&blkcg->lock, flags); |
| pn = blkio_policy_search_node(blkcg, dev, BLKIO_POLICY_THROTL, |
| BLKIO_THROTL_write_iops_device); |
| if (pn) |
| iops = pn->val.iops; |
| spin_unlock_irqrestore(&blkcg->lock, flags); |
| |
| return iops; |
| } |
| |
| /* Checks whether user asked for deleting a policy rule */ |
| static bool blkio_delete_rule_command(struct blkio_policy_node *pn) |
| { |
| switch(pn->plid) { |
| case BLKIO_POLICY_PROP: |
| if (pn->val.weight == 0) |
| return 1; |
| break; |
| case BLKIO_POLICY_THROTL: |
| switch(pn->fileid) { |
| case BLKIO_THROTL_read_bps_device: |
| case BLKIO_THROTL_write_bps_device: |
| if (pn->val.bps == 0) |
| return 1; |
| break; |
| case BLKIO_THROTL_read_iops_device: |
| case BLKIO_THROTL_write_iops_device: |
| if (pn->val.iops == 0) |
| return 1; |
| } |
| break; |
| default: |
| BUG(); |
| } |
| |
| return 0; |
| } |
| |
| static void blkio_update_policy_rule(struct blkio_policy_node *oldpn, |
| struct blkio_policy_node *newpn) |
| { |
| switch(oldpn->plid) { |
| case BLKIO_POLICY_PROP: |
| oldpn->val.weight = newpn->val.weight; |
| break; |
| case BLKIO_POLICY_THROTL: |
| switch(newpn->fileid) { |
| case BLKIO_THROTL_read_bps_device: |
| case BLKIO_THROTL_write_bps_device: |
| oldpn->val.bps = newpn->val.bps; |
| break; |
| case BLKIO_THROTL_read_iops_device: |
| case BLKIO_THROTL_write_iops_device: |
| oldpn->val.iops = newpn->val.iops; |
| } |
| break; |
| default: |
| BUG(); |
| } |
| } |
| |
| /* |
| * Some rules/values in blkg have changed. Propagate those to respective |
| * policies. |
| */ |
| static void blkio_update_blkg_policy(struct blkio_cgroup *blkcg, |
| struct blkio_group *blkg, struct blkio_policy_node *pn) |
| { |
| unsigned int weight, iops; |
| u64 bps; |
| |
| switch(pn->plid) { |
| case BLKIO_POLICY_PROP: |
| weight = pn->val.weight ? pn->val.weight : |
| blkcg->weight; |
| blkio_update_group_weight(blkg, weight); |
| break; |
| case BLKIO_POLICY_THROTL: |
| switch(pn->fileid) { |
| case BLKIO_THROTL_read_bps_device: |
| case BLKIO_THROTL_write_bps_device: |
| bps = pn->val.bps ? pn->val.bps : (-1); |
| blkio_update_group_bps(blkg, bps, pn->fileid); |
| break; |
| case BLKIO_THROTL_read_iops_device: |
| case BLKIO_THROTL_write_iops_device: |
| iops = pn->val.iops ? pn->val.iops : (-1); |
| blkio_update_group_iops(blkg, iops, pn->fileid); |
| break; |
| } |
| break; |
| default: |
| BUG(); |
| } |
| } |
| |
| /* |
| * A policy node rule has been updated. Propagate this update to all the |
| * block groups which might be affected by this update. |
| */ |
| static void blkio_update_policy_node_blkg(struct blkio_cgroup *blkcg, |
| struct blkio_policy_node *pn) |
| { |
| struct blkio_group *blkg; |
| struct hlist_node *n; |
| |
| spin_lock(&blkio_list_lock); |
| spin_lock_irq(&blkcg->lock); |
| |
| hlist_for_each_entry(blkg, n, &blkcg->blkg_list, blkcg_node) { |
| if (pn->dev != blkg->dev || pn->plid != blkg->plid) |
| continue; |
| blkio_update_blkg_policy(blkcg, blkg, pn); |
| } |
| |
| spin_unlock_irq(&blkcg->lock); |
| spin_unlock(&blkio_list_lock); |
| } |
| |
| static int blkiocg_file_write(struct cgroup *cgrp, struct cftype *cft, |
| const char *buffer) |
| { |
| int ret = 0; |
| char *buf; |
| struct blkio_policy_node *newpn, *pn; |
| struct blkio_cgroup *blkcg; |
| int keep_newpn = 0; |
| enum blkio_policy_id plid = BLKIOFILE_POLICY(cft->private); |
| int fileid = BLKIOFILE_ATTR(cft->private); |
| |
| buf = kstrdup(buffer, GFP_KERNEL); |
| if (!buf) |
| return -ENOMEM; |
| |
| newpn = kzalloc(sizeof(*newpn), GFP_KERNEL); |
| if (!newpn) { |
| ret = -ENOMEM; |
| goto free_buf; |
| } |
| |
| ret = blkio_policy_parse_and_set(buf, newpn, plid, fileid); |
| if (ret) |
| goto free_newpn; |
| |
| blkcg = cgroup_to_blkio_cgroup(cgrp); |
| |
| spin_lock_irq(&blkcg->lock); |
| |
| pn = blkio_policy_search_node(blkcg, newpn->dev, plid, fileid); |
| if (!pn) { |
| if (!blkio_delete_rule_command(newpn)) { |
| blkio_policy_insert_node(blkcg, newpn); |
| keep_newpn = 1; |
| } |
| spin_unlock_irq(&blkcg->lock); |
| goto update_io_group; |
| } |
| |
| if (blkio_delete_rule_command(newpn)) { |
| blkio_policy_delete_node(pn); |
| kfree(pn); |
| spin_unlock_irq(&blkcg->lock); |
| goto update_io_group; |
| } |
| spin_unlock_irq(&blkcg->lock); |
| |
| blkio_update_policy_rule(pn, newpn); |
| |
| update_io_group: |
| blkio_update_policy_node_blkg(blkcg, newpn); |
| |
| free_newpn: |
| if (!keep_newpn) |
| kfree(newpn); |
| free_buf: |
| kfree(buf); |
| return ret; |
| } |
| |
| static void |
| blkio_print_policy_node(struct seq_file *m, struct blkio_policy_node *pn) |
| { |
| switch(pn->plid) { |
| case BLKIO_POLICY_PROP: |
| if (pn->fileid == BLKIO_PROP_weight_device) |
| seq_printf(m, "%u:%u\t%u\n", MAJOR(pn->dev), |
| MINOR(pn->dev), pn->val.weight); |
| break; |
| case BLKIO_POLICY_THROTL: |
| switch(pn->fileid) { |
| case BLKIO_THROTL_read_bps_device: |
| case BLKIO_THROTL_write_bps_device: |
| seq_printf(m, "%u:%u\t%llu\n", MAJOR(pn->dev), |
| MINOR(pn->dev), pn->val.bps); |
| break; |
| case BLKIO_THROTL_read_iops_device: |
| case BLKIO_THROTL_write_iops_device: |
| seq_printf(m, "%u:%u\t%u\n", MAJOR(pn->dev), |
| MINOR(pn->dev), pn->val.iops); |
| break; |
| } |
| break; |
| default: |
| BUG(); |
| } |
| } |
| |
| /* cgroup files which read their data from policy nodes end up here */ |
| static void blkio_read_policy_node_files(struct cftype *cft, |
| struct blkio_cgroup *blkcg, struct seq_file *m) |
| { |
| struct blkio_policy_node *pn; |
| |
| if (!list_empty(&blkcg->policy_list)) { |
| spin_lock_irq(&blkcg->lock); |
| list_for_each_entry(pn, &blkcg->policy_list, node) { |
| if (!pn_matches_cftype(cft, pn)) |
| continue; |
| blkio_print_policy_node(m, pn); |
| } |
| spin_unlock_irq(&blkcg->lock); |
| } |
| } |
| |
| static int blkiocg_file_read(struct cgroup *cgrp, struct cftype *cft, |
| struct seq_file *m) |
| { |
| struct blkio_cgroup *blkcg; |
| enum blkio_policy_id plid = BLKIOFILE_POLICY(cft->private); |
| int name = BLKIOFILE_ATTR(cft->private); |
| |
| blkcg = cgroup_to_blkio_cgroup(cgrp); |
| |
| switch(plid) { |
| case BLKIO_POLICY_PROP: |
| switch(name) { |
| case BLKIO_PROP_weight_device: |
| blkio_read_policy_node_files(cft, blkcg, m); |
| return 0; |
| default: |
| BUG(); |
| } |
| break; |
| case BLKIO_POLICY_THROTL: |
| switch(name){ |
| case BLKIO_THROTL_read_bps_device: |
| case BLKIO_THROTL_write_bps_device: |
| case BLKIO_THROTL_read_iops_device: |
| case BLKIO_THROTL_write_iops_device: |
| blkio_read_policy_node_files(cft, blkcg, m); |
| return 0; |
| default: |
| BUG(); |
| } |
| break; |
| default: |
| BUG(); |
| } |
| |
| return 0; |
| } |
| |
| static int blkio_read_blkg_stats(struct blkio_cgroup *blkcg, |
| struct cftype *cft, struct cgroup_map_cb *cb, |
| enum stat_type type, bool show_total, bool pcpu) |
| { |
| struct blkio_group *blkg; |
| struct hlist_node *n; |
| uint64_t cgroup_total = 0; |
| |
| rcu_read_lock(); |
| hlist_for_each_entry_rcu(blkg, n, &blkcg->blkg_list, blkcg_node) { |
| if (blkg->dev) { |
| if (!cftype_blkg_same_policy(cft, blkg)) |
| continue; |
| if (pcpu) |
| cgroup_total += blkio_get_stat_cpu(blkg, cb, |
| blkg->dev, type); |
| else { |
| spin_lock_irq(&blkg->stats_lock); |
| cgroup_total += blkio_get_stat(blkg, cb, |
| blkg->dev, type); |
| spin_unlock_irq(&blkg->stats_lock); |
| } |
| } |
| } |
| if (show_total) |
| cb->fill(cb, "Total", cgroup_total); |
| rcu_read_unlock(); |
| return 0; |
| } |
| |
| /* All map kind of cgroup file get serviced by this function */ |
| static int blkiocg_file_read_map(struct cgroup *cgrp, struct cftype *cft, |
| struct cgroup_map_cb *cb) |
| { |
| struct blkio_cgroup *blkcg; |
| enum blkio_policy_id plid = BLKIOFILE_POLICY(cft->private); |
| int name = BLKIOFILE_ATTR(cft->private); |
| |
| blkcg = cgroup_to_blkio_cgroup(cgrp); |
| |
| switch(plid) { |
| case BLKIO_POLICY_PROP: |
| switch(name) { |
| case BLKIO_PROP_time: |
| return blkio_read_blkg_stats(blkcg, cft, cb, |
| BLKIO_STAT_TIME, 0, 0); |
| case BLKIO_PROP_sectors: |
| return blkio_read_blkg_stats(blkcg, cft, cb, |
| BLKIO_STAT_CPU_SECTORS, 0, 1); |
| case BLKIO_PROP_io_service_bytes: |
| return blkio_read_blkg_stats(blkcg, cft, cb, |
| BLKIO_STAT_CPU_SERVICE_BYTES, 1, 1); |
| case BLKIO_PROP_io_serviced: |
| return blkio_read_blkg_stats(blkcg, cft, cb, |
| BLKIO_STAT_CPU_SERVICED, 1, 1); |
| case BLKIO_PROP_io_service_time: |
| return blkio_read_blkg_stats(blkcg, cft, cb, |
| BLKIO_STAT_SERVICE_TIME, 1, 0); |
| case BLKIO_PROP_io_wait_time: |
| return blkio_read_blkg_stats(blkcg, cft, cb, |
| BLKIO_STAT_WAIT_TIME, 1, 0); |
| case BLKIO_PROP_io_merged: |
| return blkio_read_blkg_stats(blkcg, cft, cb, |
| BLKIO_STAT_CPU_MERGED, 1, 1); |
| case BLKIO_PROP_io_queued: |
| return blkio_read_blkg_stats(blkcg, cft, cb, |
| BLKIO_STAT_QUEUED, 1, 0); |
| #ifdef CONFIG_DEBUG_BLK_CGROUP |
| case BLKIO_PROP_unaccounted_time: |
| return blkio_read_blkg_stats(blkcg, cft, cb, |
| BLKIO_STAT_UNACCOUNTED_TIME, 0, 0); |
| case BLKIO_PROP_dequeue: |
| return blkio_read_blkg_stats(blkcg, cft, cb, |
| BLKIO_STAT_DEQUEUE, 0, 0); |
| case BLKIO_PROP_avg_queue_size: |
| return blkio_read_blkg_stats(blkcg, cft, cb, |
| BLKIO_STAT_AVG_QUEUE_SIZE, 0, 0); |
| case BLKIO_PROP_group_wait_time: |
| return blkio_read_blkg_stats(blkcg, cft, cb, |
| BLKIO_STAT_GROUP_WAIT_TIME, 0, 0); |
| case BLKIO_PROP_idle_time: |
| return blkio_read_blkg_stats(blkcg, cft, cb, |
| BLKIO_STAT_IDLE_TIME, 0, 0); |
| case BLKIO_PROP_empty_time: |
| return blkio_read_blkg_stats(blkcg, cft, cb, |
| BLKIO_STAT_EMPTY_TIME, 0, 0); |
| #endif |
| default: |
| BUG(); |
| } |
| break; |
| case BLKIO_POLICY_THROTL: |
| switch(name){ |
| case BLKIO_THROTL_io_service_bytes: |
| return blkio_read_blkg_stats(blkcg, cft, cb, |
| BLKIO_STAT_CPU_SERVICE_BYTES, 1, 1); |
| case BLKIO_THROTL_io_serviced: |
| return blkio_read_blkg_stats(blkcg, cft, cb, |
| BLKIO_STAT_CPU_SERVICED, 1, 1); |
| default: |
| BUG(); |
| } |
| break; |
| default: |
| BUG(); |
| } |
| |
| return 0; |
| } |
| |
| static int blkio_weight_write(struct blkio_cgroup *blkcg, u64 val) |
| { |
| struct blkio_group *blkg; |
| struct hlist_node *n; |
| struct blkio_policy_node *pn; |
| |
| if (val < BLKIO_WEIGHT_MIN || val > BLKIO_WEIGHT_MAX) |
| return -EINVAL; |
| |
| spin_lock(&blkio_list_lock); |
| spin_lock_irq(&blkcg->lock); |
| blkcg->weight = (unsigned int)val; |
| |
| hlist_for_each_entry(blkg, n, &blkcg->blkg_list, blkcg_node) { |
| pn = blkio_policy_search_node(blkcg, blkg->dev, |
| BLKIO_POLICY_PROP, BLKIO_PROP_weight_device); |
| if (pn) |
| continue; |
| |
| blkio_update_group_weight(blkg, blkcg->weight); |
| } |
| spin_unlock_irq(&blkcg->lock); |
| spin_unlock(&blkio_list_lock); |
| return 0; |
| } |
| |
| static u64 blkiocg_file_read_u64 (struct cgroup *cgrp, struct cftype *cft) { |
| struct blkio_cgroup *blkcg; |
| enum blkio_policy_id plid = BLKIOFILE_POLICY(cft->private); |
| int name = BLKIOFILE_ATTR(cft->private); |
| |
| blkcg = cgroup_to_blkio_cgroup(cgrp); |
| |
| switch(plid) { |
| case BLKIO_POLICY_PROP: |
| switch(name) { |
| case BLKIO_PROP_weight: |
| return (u64)blkcg->weight; |
| } |
| break; |
| default: |
| BUG(); |
| } |
| return 0; |
| } |
| |
| static int |
| blkiocg_file_write_u64(struct cgroup *cgrp, struct cftype *cft, u64 val) |
| { |
| struct blkio_cgroup *blkcg; |
| enum blkio_policy_id plid = BLKIOFILE_POLICY(cft->private); |
| int name = BLKIOFILE_ATTR(cft->private); |
| |
| blkcg = cgroup_to_blkio_cgroup(cgrp); |
| |
| switch(plid) { |
| case BLKIO_POLICY_PROP: |
| switch(name) { |
| case BLKIO_PROP_weight: |
| return blkio_weight_write(blkcg, val); |
| } |
| break; |
| default: |
| BUG(); |
| } |
| |
| return 0; |
| } |
| |
| struct cftype blkio_files[] = { |
| { |
| .name = "weight_device", |
| .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
| BLKIO_PROP_weight_device), |
| .read_seq_string = blkiocg_file_read, |
| .write_string = blkiocg_file_write, |
| .max_write_len = 256, |
| }, |
| { |
| .name = "weight", |
| .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
| BLKIO_PROP_weight), |
| .read_u64 = blkiocg_file_read_u64, |
| .write_u64 = blkiocg_file_write_u64, |
| }, |
| { |
| .name = "time", |
| .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
| BLKIO_PROP_time), |
| .read_map = blkiocg_file_read_map, |
| }, |
| { |
| .name = "sectors", |
| .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
| BLKIO_PROP_sectors), |
| .read_map = blkiocg_file_read_map, |
| }, |
| { |
| .name = "io_service_bytes", |
| .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
| BLKIO_PROP_io_service_bytes), |
| .read_map = blkiocg_file_read_map, |
| }, |
| { |
| .name = "io_serviced", |
| .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
| BLKIO_PROP_io_serviced), |
| .read_map = blkiocg_file_read_map, |
| }, |
| { |
| .name = "io_service_time", |
| .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
| BLKIO_PROP_io_service_time), |
| .read_map = blkiocg_file_read_map, |
| }, |
| { |
| .name = "io_wait_time", |
| .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
| BLKIO_PROP_io_wait_time), |
| .read_map = blkiocg_file_read_map, |
| }, |
| { |
| .name = "io_merged", |
| .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
| BLKIO_PROP_io_merged), |
| .read_map = blkiocg_file_read_map, |
| }, |
| { |
| .name = "io_queued", |
| .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
| BLKIO_PROP_io_queued), |
| .read_map = blkiocg_file_read_map, |
| }, |
| { |
| .name = "reset_stats", |
| .write_u64 = blkiocg_reset_stats, |
| }, |
| #ifdef CONFIG_BLK_DEV_THROTTLING |
| { |
| .name = "throttle.read_bps_device", |
| .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_THROTL, |
| BLKIO_THROTL_read_bps_device), |
| .read_seq_string = blkiocg_file_read, |
| .write_string = blkiocg_file_write, |
| .max_write_len = 256, |
| }, |
| |
| { |
| .name = "throttle.write_bps_device", |
| .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_THROTL, |
| BLKIO_THROTL_write_bps_device), |
| .read_seq_string = blkiocg_file_read, |
| .write_string = blkiocg_file_write, |
| .max_write_len = 256, |
| }, |
| |
| { |
| .name = "throttle.read_iops_device", |
| .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_THROTL, |
| BLKIO_THROTL_read_iops_device), |
| .read_seq_string = blkiocg_file_read, |
| .write_string = blkiocg_file_write, |
| .max_write_len = 256, |
| }, |
| |
| { |
| .name = "throttle.write_iops_device", |
| .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_THROTL, |
| BLKIO_THROTL_write_iops_device), |
| .read_seq_string = blkiocg_file_read, |
| .write_string = blkiocg_file_write, |
| .max_write_len = 256, |
| }, |
| { |
| .name = "throttle.io_service_bytes", |
| .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_THROTL, |
| BLKIO_THROTL_io_service_bytes), |
| .read_map = blkiocg_file_read_map, |
| }, |
| { |
| .name = "throttle.io_serviced", |
| .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_THROTL, |
| BLKIO_THROTL_io_serviced), |
| .read_map = blkiocg_file_read_map, |
| }, |
| #endif /* CONFIG_BLK_DEV_THROTTLING */ |
| |
| #ifdef CONFIG_DEBUG_BLK_CGROUP |
| { |
| .name = "avg_queue_size", |
| .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
| BLKIO_PROP_avg_queue_size), |
| .read_map = blkiocg_file_read_map, |
| }, |
| { |
| .name = "group_wait_time", |
| .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
| BLKIO_PROP_group_wait_time), |
| .read_map = blkiocg_file_read_map, |
| }, |
| { |
| .name = "idle_time", |
| .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
| BLKIO_PROP_idle_time), |
| .read_map = blkiocg_file_read_map, |
| }, |
| { |
| .name = "empty_time", |
| .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
| BLKIO_PROP_empty_time), |
| .read_map = blkiocg_file_read_map, |
| }, |
| { |
| .name = "dequeue", |
| .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
| BLKIO_PROP_dequeue), |
| .read_map = blkiocg_file_read_map, |
| }, |
| { |
| .name = "unaccounted_time", |
| .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
| BLKIO_PROP_unaccounted_time), |
| .read_map = blkiocg_file_read_map, |
| }, |
| #endif |
| }; |
| |
| static int blkiocg_populate(struct cgroup_subsys *subsys, struct cgroup *cgroup) |
| { |
| return cgroup_add_files(cgroup, subsys, blkio_files, |
| ARRAY_SIZE(blkio_files)); |
| } |
| |
| static void blkiocg_destroy(struct cgroup_subsys *subsys, struct cgroup *cgroup) |
| { |
| struct blkio_cgroup *blkcg = cgroup_to_blkio_cgroup(cgroup); |
| unsigned long flags; |
| struct blkio_group *blkg; |
| void *key; |
| struct blkio_policy_type *blkiop; |
| struct blkio_policy_node *pn, *pntmp; |
| |
| rcu_read_lock(); |
| do { |
| spin_lock_irqsave(&blkcg->lock, flags); |
| |
| if (hlist_empty(&blkcg->blkg_list)) { |
| spin_unlock_irqrestore(&blkcg->lock, flags); |
| break; |
| } |
| |
| blkg = hlist_entry(blkcg->blkg_list.first, struct blkio_group, |
| blkcg_node); |
| key = rcu_dereference(blkg->key); |
| __blkiocg_del_blkio_group(blkg); |
| |
| spin_unlock_irqrestore(&blkcg->lock, flags); |
| |
| /* |
| * This blkio_group is being unlinked as associated cgroup is |
| * going away. Let all the IO controlling policies know about |
| * this event. |
| */ |
| spin_lock(&blkio_list_lock); |
| list_for_each_entry(blkiop, &blkio_list, list) { |
| if (blkiop->plid != blkg->plid) |
| continue; |
| blkiop->ops.blkio_unlink_group_fn(key, blkg); |
| } |
| spin_unlock(&blkio_list_lock); |
| } while (1); |
| |
| list_for_each_entry_safe(pn, pntmp, &blkcg->policy_list, node) { |
| blkio_policy_delete_node(pn); |
| kfree(pn); |
| } |
| |
| free_css_id(&blkio_subsys, &blkcg->css); |
| rcu_read_unlock(); |
| if (blkcg != &blkio_root_cgroup) |
| kfree(blkcg); |
| } |
| |
| static struct cgroup_subsys_state * |
| blkiocg_create(struct cgroup_subsys *subsys, struct cgroup *cgroup) |
| { |
| struct blkio_cgroup *blkcg; |
| struct cgroup *parent = cgroup->parent; |
| |
| if (!parent) { |
| blkcg = &blkio_root_cgroup; |
| goto done; |
| } |
| |
| blkcg = kzalloc(sizeof(*blkcg), GFP_KERNEL); |
| if (!blkcg) |
| return ERR_PTR(-ENOMEM); |
| |
| blkcg->weight = BLKIO_WEIGHT_DEFAULT; |
| done: |
| spin_lock_init(&blkcg->lock); |
| INIT_HLIST_HEAD(&blkcg->blkg_list); |
| |
| INIT_LIST_HEAD(&blkcg->policy_list); |
| return &blkcg->css; |
| } |
| |
| /* |
| * We cannot support shared io contexts, as we have no mean to support |
| * two tasks with the same ioc in two different groups without major rework |
| * of the main cic data structures. For now we allow a task to change |
| * its cgroup only if it's the only owner of its ioc. |
| */ |
| static int blkiocg_can_attach(struct cgroup_subsys *ss, struct cgroup *cgrp, |
| struct cgroup_taskset *tset) |
| { |
| struct task_struct *task; |
| struct io_context *ioc; |
| int ret = 0; |
| |
| /* task_lock() is needed to avoid races with exit_io_context() */ |
| cgroup_taskset_for_each(task, cgrp, tset) { |
| task_lock(task); |
| ioc = task->io_context; |
| if (ioc && atomic_read(&ioc->nr_tasks) > 1) |
| ret = -EINVAL; |
| task_unlock(task); |
| if (ret) |
| break; |
| } |
| return ret; |
| } |
| |
| static void blkiocg_attach(struct cgroup_subsys *ss, struct cgroup *cgrp, |
| struct cgroup_taskset *tset) |
| { |
| struct task_struct *task; |
| struct io_context *ioc; |
| |
| cgroup_taskset_for_each(task, cgrp, tset) { |
| task_lock(task); |
| ioc = task->io_context; |
| if (ioc) |
| ioc->cgroup_changed = 1; |
| task_unlock(task); |
| } |
| } |
| |
| void blkio_policy_register(struct blkio_policy_type *blkiop) |
| { |
| spin_lock(&blkio_list_lock); |
| list_add_tail(&blkiop->list, &blkio_list); |
| spin_unlock(&blkio_list_lock); |
| } |
| EXPORT_SYMBOL_GPL(blkio_policy_register); |
| |
| void blkio_policy_unregister(struct blkio_policy_type *blkiop) |
| { |
| spin_lock(&blkio_list_lock); |
| list_del_init(&blkiop->list); |
| spin_unlock(&blkio_list_lock); |
| } |
| EXPORT_SYMBOL_GPL(blkio_policy_unregister); |
| |
| static int __init init_cgroup_blkio(void) |
| { |
| return cgroup_load_subsys(&blkio_subsys); |
| } |
| |
| static void __exit exit_cgroup_blkio(void) |
| { |
| cgroup_unload_subsys(&blkio_subsys); |
| } |
| |
| module_init(init_cgroup_blkio); |
| module_exit(exit_cgroup_blkio); |
| MODULE_LICENSE("GPL"); |