From 41b38b6d540f951c49315d8573e6f6195a6e736d Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Sun, 1 Apr 2012 14:38:44 -0700 Subject: blkcg: cfq doesn't need per-cpu dispatch stats blkio_group_stats_cpu is used to count dispatch stats using per-cpu counters. This is used by both blk-throtl and cfq-iosched but the sharing is rather silly. * cfq-iosched doesn't need per-cpu dispatch stats. cfq always updates those stats while holding queue_lock. * blk-throtl needs per-cpu dispatch stats but only service_bytes and serviced. It doesn't make use of sectors. This patch makes cfq add and use global stats for service_bytes, serviced and sectors, removes per-cpu sectors counter and moves per-cpu stat printing code to blk-throttle.c. Signed-off-by: Tejun Heo --- block/blk-cgroup.c | 63 ++---------------------------------------------------- 1 file changed, 2 insertions(+), 61 deletions(-) (limited to 'block/blk-cgroup.c') diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index 821a0a393e85..19ee29f1b7c5 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -390,7 +390,6 @@ static void blkio_reset_stats_cpu(struct blkio_group *blkg, int plid) blkg_rwstat_reset(&sc->service_bytes); blkg_rwstat_reset(&sc->serviced); - blkg_stat_reset(&sc->sectors); } } @@ -417,6 +416,8 @@ blkiocg_reset_stats(struct cgroup *cgroup, struct cftype *cftype, u64 val) struct blkio_group_stats *stats = &pd->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); @@ -577,66 +578,6 @@ int blkcg_print_rwstat(struct cgroup *cgrp, struct cftype *cft, } EXPORT_SYMBOL_GPL(blkcg_print_rwstat); -static u64 blkg_prfill_cpu_stat(struct seq_file *sf, - struct blkg_policy_data *pd, int off) -{ - u64 v = 0; - int cpu; - - for_each_possible_cpu(cpu) { - struct blkio_group_stats_cpu *sc = - per_cpu_ptr(pd->stats_cpu, cpu); - - v += blkg_stat_read((void *)sc + off); - } - - return __blkg_prfill_u64(sf, pd, v); -} - -static u64 blkg_prfill_cpu_rwstat(struct seq_file *sf, - struct blkg_policy_data *pd, int off) -{ - struct blkg_rwstat rwstat = { }, tmp; - int i, cpu; - - for_each_possible_cpu(cpu) { - struct blkio_group_stats_cpu *sc = - per_cpu_ptr(pd->stats_cpu, cpu); - - tmp = blkg_rwstat_read((void *)sc + off); - for (i = 0; i < BLKG_RWSTAT_NR; i++) - rwstat.cnt[i] += tmp.cnt[i]; - } - - return __blkg_prfill_rwstat(sf, pd, &rwstat); -} - -/* print per-cpu blkg_stat specified by BLKCG_STAT_PRIV() */ -int blkcg_print_cpu_stat(struct cgroup *cgrp, struct cftype *cft, - struct seq_file *sf) -{ - struct blkio_cgroup *blkcg = cgroup_to_blkio_cgroup(cgrp); - - blkcg_print_blkgs(sf, blkcg, blkg_prfill_cpu_stat, - BLKCG_STAT_POL(cft->private), - BLKCG_STAT_OFF(cft->private), false); - return 0; -} -EXPORT_SYMBOL_GPL(blkcg_print_cpu_stat); - -/* print per-cpu blkg_rwstat specified by BLKCG_STAT_PRIV() */ -int blkcg_print_cpu_rwstat(struct cgroup *cgrp, struct cftype *cft, - struct seq_file *sf) -{ - struct blkio_cgroup *blkcg = cgroup_to_blkio_cgroup(cgrp); - - blkcg_print_blkgs(sf, blkcg, blkg_prfill_cpu_rwstat, - BLKCG_STAT_POL(cft->private), - BLKCG_STAT_OFF(cft->private), true); - return 0; -} -EXPORT_SYMBOL_GPL(blkcg_print_cpu_rwstat); - /** * blkg_conf_prep - parse and prepare for per-blkg config update * @blkcg: target block cgroup -- cgit v1.2.3-59-g8ed1b