From c0ce79dca5b0e8373a546ebea2af7b3df94c584e Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 6 Jun 2019 12:26:22 +0200 Subject: blk-cgroup: move struct blkg_stat to bfq This structure and assorted infrastructure is only used by the bfq I/O scheduler. Move it there instead of bloating the common code. Acked-by: Tejun Heo Acked-by: Paolo Valente Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/bfq-cgroup.c | 192 ++++++++++++++++++++++++++++++++++++++++++----------- 1 file changed, 155 insertions(+), 37 deletions(-) (limited to 'block/bfq-cgroup.c') diff --git a/block/bfq-cgroup.c b/block/bfq-cgroup.c index 624374a99c6e..a691dca7e966 100644 --- a/block/bfq-cgroup.c +++ b/block/bfq-cgroup.c @@ -17,6 +17,124 @@ #if defined(CONFIG_BFQ_GROUP_IOSCHED) && defined(CONFIG_DEBUG_BLK_CGROUP) +static int bfq_stat_init(struct bfq_stat *stat, gfp_t gfp) +{ + int ret; + + ret = percpu_counter_init(&stat->cpu_cnt, 0, gfp); + if (ret) + return ret; + + atomic64_set(&stat->aux_cnt, 0); + return 0; +} + +static void bfq_stat_exit(struct bfq_stat *stat) +{ + percpu_counter_destroy(&stat->cpu_cnt); +} + +/** + * bfq_stat_add - add a value to a bfq_stat + * @stat: target bfq_stat + * @val: value to add + * + * Add @val to @stat. The caller must ensure that IRQ on the same CPU + * don't re-enter this function for the same counter. + */ +static inline void bfq_stat_add(struct bfq_stat *stat, uint64_t val) +{ + percpu_counter_add_batch(&stat->cpu_cnt, val, BLKG_STAT_CPU_BATCH); +} + +/** + * bfq_stat_read - read the current value of a bfq_stat + * @stat: bfq_stat to read + */ +static inline uint64_t bfq_stat_read(struct bfq_stat *stat) +{ + return percpu_counter_sum_positive(&stat->cpu_cnt); +} + +/** + * bfq_stat_reset - reset a bfq_stat + * @stat: bfq_stat to reset + */ +static inline void bfq_stat_reset(struct bfq_stat *stat) +{ + percpu_counter_set(&stat->cpu_cnt, 0); + atomic64_set(&stat->aux_cnt, 0); +} + +/** + * bfq_stat_add_aux - add a bfq_stat into another's aux count + * @to: the destination bfq_stat + * @from: the source + * + * Add @from's count including the aux one to @to's aux count. + */ +static inline void bfq_stat_add_aux(struct bfq_stat *to, + struct bfq_stat *from) +{ + atomic64_add(bfq_stat_read(from) + atomic64_read(&from->aux_cnt), + &to->aux_cnt); +} + +/** + * bfq_stat_recursive_sum - collect hierarchical bfq_stat + * @blkg: blkg of interest + * @pol: blkcg_policy which contains the bfq_stat + * @off: offset to the bfq_stat in blkg_policy_data or @blkg + * + * Collect the bfq_stat specified by @blkg, @pol and @off and all its + * online descendants and their aux counts. The caller must be holding the + * queue lock for online tests. + * + * If @pol is NULL, bfq_stat is at @off bytes into @blkg; otherwise, it is + * at @off bytes into @blkg's blkg_policy_data of the policy. + */ +static u64 bfq_stat_recursive_sum(struct blkcg_gq *blkg, + struct blkcg_policy *pol, int off) +{ + struct blkcg_gq *pos_blkg; + struct cgroup_subsys_state *pos_css; + u64 sum = 0; + + lockdep_assert_held(&blkg->q->queue_lock); + + rcu_read_lock(); + blkg_for_each_descendant_pre(pos_blkg, pos_css, blkg) { + struct bfq_stat *stat; + + if (!pos_blkg->online) + continue; + + if (pol) + stat = (void *)blkg_to_pd(pos_blkg, pol) + off; + else + stat = (void *)blkg + off; + + sum += bfq_stat_read(stat) + atomic64_read(&stat->aux_cnt); + } + rcu_read_unlock(); + + return sum; +} + +/** + * blkg_prfill_stat - prfill callback for bfq_stat + * @sf: seq_file to print to + * @pd: policy private data of interest + * @off: offset to the bfq_stat in @pd + * + * prfill callback for printing a bfq_stat. + */ +static u64 blkg_prfill_stat(struct seq_file *sf, struct blkg_policy_data *pd, + int off) +{ + return __blkg_prfill_u64(sf, pd, bfq_stat_read((void *)pd + off)); +} + /* bfqg stats flags */ enum bfqg_stats_flags { BFQG_stats_waiting = 0, @@ -53,7 +171,7 @@ static void bfqg_stats_update_group_wait_time(struct bfqg_stats *stats) now = ktime_get_ns(); if (now > stats->start_group_wait_time) - blkg_stat_add(&stats->group_wait_time, + bfq_stat_add(&stats->group_wait_time, now - stats->start_group_wait_time); bfqg_stats_clear_waiting(stats); } @@ -82,14 +200,14 @@ static void bfqg_stats_end_empty_time(struct bfqg_stats *stats) now = ktime_get_ns(); if (now > stats->start_empty_time) - blkg_stat_add(&stats->empty_time, + bfq_stat_add(&stats->empty_time, now - stats->start_empty_time); bfqg_stats_clear_empty(stats); } void bfqg_stats_update_dequeue(struct bfq_group *bfqg) { - blkg_stat_add(&bfqg->stats.dequeue, 1); + bfq_stat_add(&bfqg->stats.dequeue, 1); } void bfqg_stats_set_start_empty_time(struct bfq_group *bfqg) @@ -119,7 +237,7 @@ void bfqg_stats_update_idle_time(struct bfq_group *bfqg) u64 now = ktime_get_ns(); if (now > stats->start_idle_time) - blkg_stat_add(&stats->idle_time, + bfq_stat_add(&stats->idle_time, now - stats->start_idle_time); bfqg_stats_clear_idling(stats); } @@ -137,9 +255,9 @@ void bfqg_stats_update_avg_queue_size(struct bfq_group *bfqg) { struct bfqg_stats *stats = &bfqg->stats; - blkg_stat_add(&stats->avg_queue_size_sum, + bfq_stat_add(&stats->avg_queue_size_sum, blkg_rwstat_total(&stats->queued)); - blkg_stat_add(&stats->avg_queue_size_samples, 1); + bfq_stat_add(&stats->avg_queue_size_samples, 1); bfqg_stats_update_group_wait_time(stats); } @@ -279,13 +397,13 @@ static void bfqg_stats_reset(struct bfqg_stats *stats) blkg_rwstat_reset(&stats->merged); blkg_rwstat_reset(&stats->service_time); blkg_rwstat_reset(&stats->wait_time); - blkg_stat_reset(&stats->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); + bfq_stat_reset(&stats->time); + bfq_stat_reset(&stats->avg_queue_size_sum); + bfq_stat_reset(&stats->avg_queue_size_samples); + bfq_stat_reset(&stats->dequeue); + bfq_stat_reset(&stats->group_wait_time); + bfq_stat_reset(&stats->idle_time); + bfq_stat_reset(&stats->empty_time); #endif } @@ -300,14 +418,14 @@ static void bfqg_stats_add_aux(struct bfqg_stats *to, struct bfqg_stats *from) blkg_rwstat_add_aux(&to->merged, &from->merged); blkg_rwstat_add_aux(&to->service_time, &from->service_time); blkg_rwstat_add_aux(&to->wait_time, &from->wait_time); - blkg_stat_add_aux(&from->time, &from->time); - blkg_stat_add_aux(&to->avg_queue_size_sum, &from->avg_queue_size_sum); - blkg_stat_add_aux(&to->avg_queue_size_samples, + bfq_stat_add_aux(&from->time, &from->time); + bfq_stat_add_aux(&to->avg_queue_size_sum, &from->avg_queue_size_sum); + bfq_stat_add_aux(&to->avg_queue_size_samples, &from->avg_queue_size_samples); - blkg_stat_add_aux(&to->dequeue, &from->dequeue); - blkg_stat_add_aux(&to->group_wait_time, &from->group_wait_time); - blkg_stat_add_aux(&to->idle_time, &from->idle_time); - blkg_stat_add_aux(&to->empty_time, &from->empty_time); + bfq_stat_add_aux(&to->dequeue, &from->dequeue); + bfq_stat_add_aux(&to->group_wait_time, &from->group_wait_time); + bfq_stat_add_aux(&to->idle_time, &from->idle_time); + bfq_stat_add_aux(&to->empty_time, &from->empty_time); #endif } @@ -360,13 +478,13 @@ static void bfqg_stats_exit(struct bfqg_stats *stats) blkg_rwstat_exit(&stats->service_time); blkg_rwstat_exit(&stats->wait_time); blkg_rwstat_exit(&stats->queued); - blkg_stat_exit(&stats->time); - blkg_stat_exit(&stats->avg_queue_size_sum); - blkg_stat_exit(&stats->avg_queue_size_samples); - blkg_stat_exit(&stats->dequeue); - blkg_stat_exit(&stats->group_wait_time); - blkg_stat_exit(&stats->idle_time); - blkg_stat_exit(&stats->empty_time); + bfq_stat_exit(&stats->time); + bfq_stat_exit(&stats->avg_queue_size_sum); + bfq_stat_exit(&stats->avg_queue_size_samples); + bfq_stat_exit(&stats->dequeue); + bfq_stat_exit(&stats->group_wait_time); + bfq_stat_exit(&stats->idle_time); + bfq_stat_exit(&stats->empty_time); #endif } @@ -377,13 +495,13 @@ static int bfqg_stats_init(struct bfqg_stats *stats, gfp_t gfp) blkg_rwstat_init(&stats->service_time, gfp) || blkg_rwstat_init(&stats->wait_time, gfp) || blkg_rwstat_init(&stats->queued, gfp) || - blkg_stat_init(&stats->time, gfp) || - blkg_stat_init(&stats->avg_queue_size_sum, gfp) || - blkg_stat_init(&stats->avg_queue_size_samples, gfp) || - blkg_stat_init(&stats->dequeue, gfp) || - blkg_stat_init(&stats->group_wait_time, gfp) || - blkg_stat_init(&stats->idle_time, gfp) || - blkg_stat_init(&stats->empty_time, gfp)) { + bfq_stat_init(&stats->time, gfp) || + bfq_stat_init(&stats->avg_queue_size_sum, gfp) || + bfq_stat_init(&stats->avg_queue_size_samples, gfp) || + bfq_stat_init(&stats->dequeue, gfp) || + bfq_stat_init(&stats->group_wait_time, gfp) || + bfq_stat_init(&stats->idle_time, gfp) || + bfq_stat_init(&stats->empty_time, gfp)) { bfqg_stats_exit(stats); return -ENOMEM; } @@ -927,7 +1045,7 @@ static int bfqg_print_rwstat(struct seq_file *sf, void *v) static u64 bfqg_prfill_stat_recursive(struct seq_file *sf, struct blkg_policy_data *pd, int off) { - u64 sum = blkg_stat_recursive_sum(pd_to_blkg(pd), + u64 sum = bfq_stat_recursive_sum(pd_to_blkg(pd), &blkcg_policy_bfq, off); return __blkg_prfill_u64(sf, pd, sum); } @@ -996,11 +1114,11 @@ static u64 bfqg_prfill_avg_queue_size(struct seq_file *sf, struct blkg_policy_data *pd, int off) { struct bfq_group *bfqg = pd_to_bfqg(pd); - u64 samples = blkg_stat_read(&bfqg->stats.avg_queue_size_samples); + u64 samples = bfq_stat_read(&bfqg->stats.avg_queue_size_samples); u64 v = 0; if (samples) { - v = blkg_stat_read(&bfqg->stats.avg_queue_size_sum); + v = bfq_stat_read(&bfqg->stats.avg_queue_size_sum); v = div64_u64(v, samples); } __blkg_prfill_u64(sf, pd, v); -- cgit v1.2.3