From 702747cabe737fe9b358739443d539f10cc7c715 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Tue, 18 Aug 2015 14:55:25 -0700 Subject: [PATCH] blkcg: remove cfqg_stats->sectors cfq_stats->sectors is a blkg_stat which keeps track of the total number of sectors serviced; however, this can be trivially calculated from blkcg_gq->stat_bytes. The only thing necessary is adding up READs and WRITEs and then dividing by sector size. Remove cfqg_stats->sectors and make cfq print "sectors" and "sectors_recursive" from stat_bytes. While this is a bit more code, it removes duplicate stat allocations and updates and ensures that the reported stats stay in tune with each other. Signed-off-by: Tejun Heo Cc: Vivek Goyal Signed-off-by: Jens Axboe --- block/cfq-iosched.c | 55 +++++++++++++++++++++++++++++---------------- 1 file changed, 36 insertions(+), 19 deletions(-) diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index a948d4df3fc3..395476ab14fe 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -185,8 +185,6 @@ struct cfqg_stats { 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 @@ -688,12 +686,6 @@ 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); -} - static inline void cfqg_stats_update_completion(struct cfq_group *cfqg, uint64_t start_time, uint64_t io_start_time, int rw) { @@ -782,8 +774,6 @@ 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) { } @@ -1538,8 +1528,6 @@ static void cfqg_stats_exit(struct cfqg_stats *stats) blkg_rwstat_exit(&stats->service_time); blkg_rwstat_exit(&stats->wait_time); blkg_rwstat_exit(&stats->queued); - - blkg_stat_exit(&stats->sectors); blkg_stat_exit(&stats->time); #ifdef CONFIG_DEBUG_BLK_CGROUP blkg_stat_exit(&stats->unaccounted_time); @@ -1558,8 +1546,6 @@ static int cfqg_stats_init(struct cfqg_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->sectors, gfp) || blkg_stat_init(&stats->time, gfp)) goto err; @@ -1901,6 +1887,40 @@ static int cfqg_print_rwstat_recursive(struct seq_file *sf, void *v) return 0; } +static u64 cfqg_prfill_sectors(struct seq_file *sf, struct blkg_policy_data *pd, + int off) +{ + u64 sum = blkg_rwstat_total(&pd->blkg->stat_bytes); + + return __blkg_prfill_u64(sf, pd, sum >> 9); +} + +static int cfqg_print_stat_sectors(struct seq_file *sf, void *v) +{ + blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), + cfqg_prfill_sectors, &blkcg_policy_cfq, 0, false); + return 0; +} + +static u64 cfqg_prfill_sectors_recursive(struct seq_file *sf, + struct blkg_policy_data *pd, int off) +{ + struct blkg_rwstat tmp = blkg_rwstat_recursive_sum(pd->blkg, NULL, + offsetof(struct blkcg_gq, stat_bytes)); + u64 sum = atomic64_read(&tmp.aux_cnt[BLKG_RWSTAT_READ]) + + atomic64_read(&tmp.aux_cnt[BLKG_RWSTAT_WRITE]); + + return __blkg_prfill_u64(sf, pd, sum >> 9); +} + +static int cfqg_print_stat_sectors_recursive(struct seq_file *sf, void *v) +{ + blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), + cfqg_prfill_sectors_recursive, &blkcg_policy_cfq, 0, + false); + return 0; +} + #ifdef CONFIG_DEBUG_BLK_CGROUP static u64 cfqg_prfill_avg_queue_size(struct seq_file *sf, struct blkg_policy_data *pd, int off) @@ -1975,8 +1995,7 @@ static struct cftype cfq_blkcg_files[] = { }, { .name = "sectors", - .private = offsetof(struct cfq_group, stats.sectors), - .seq_show = cfqg_print_stat, + .seq_show = cfqg_print_stat_sectors, }, { .name = "io_service_bytes", @@ -2017,8 +2036,7 @@ static struct cftype cfq_blkcg_files[] = { }, { .name = "sectors_recursive", - .private = offsetof(struct cfq_group, stats.sectors), - .seq_show = cfqg_print_stat_recursive, + .seq_show = cfqg_print_stat_sectors_recursive, }, { .name = "io_service_bytes_recursive", @@ -2888,7 +2906,6 @@ 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); - cfqg_stats_update_dispatch(cfqq->cfqg, blk_rq_bytes(rq), rq->cmd_flags); } /* -- 2.34.1