From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: [PATCH 6/6] blkcg: remove cfqg_stats->sectors Date: Thu, 25 Jun 2015 17:38:57 -0400 Message-ID: <1435268337-1738-7-git-send-email-tj@kernel.org> References: <1435268337-1738-1-git-send-email-tj@kernel.org> Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=sender:from:to:cc:subject:date:message-id:in-reply-to:references; bh=krAQzX2KJNKY238kLzEvYtdrxakjjEOcFLyJ29eXSVs=; b=RoF1nE4CaFswiv52im9PvxE1xj9ks1ExPfOOhK/5BdXDmal30BP5HYvpC18V/UL+Af PFJ+JOc1FWYEzlrdJtcF+7FCpyt5qQp4b6URS39cqp5uUwcBj2lzXXSwXJpZyIPhzq8B PHAhLpmufdKsn5iB00ZGJ8YxlPkxr1Mw4lFtS6sfgTLiKhL+ISOoMcWGL1h//+8544MA XZiu/sHsTMPRqJY79JWRxf2cSepFMRfFHycJ8PGO4mcjwpD+I9w89jcSTvBVel6TtpGK yzUoh423VC2spiDapvQQWoQQ8WHFQQh+sbpeMEB2AejseKnh/eePJJpQfyn2Bku/uiSN 1IDg== In-Reply-To: <1435268337-1738-1-git-send-email-tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org> Sender: cgroups-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: axboe-tSWWG44O7X1aa/9Udqfwiw@public.gmane.org Cc: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, vgoyal-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, avanzini.arianna-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, kernel-team-b10kYP2dOMg@public.gmane.org, Tejun Heo 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 --- 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 a6dd941..90b5bfe 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -180,8 +180,6 @@ 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 @@ -663,12 +661,6 @@ 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) { @@ -757,8 +749,6 @@ 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) { } @@ -1513,8 +1503,6 @@ 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); @@ -1533,8 +1521,6 @@ 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; @@ -1833,6 +1819,40 @@ 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) @@ -1907,8 +1927,7 @@ 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", @@ -1949,8 +1968,7 @@ 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", @@ -2820,7 +2838,6 @@ 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); } /* -- 2.4.3