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| author | Tejun Heo <tj@kernel.org> | 2012-04-01 14:38:44 -0700 |
|---|---|---|
| committer | Tejun Heo <tj@kernel.org> | 2012-04-01 14:38:44 -0700 |
| commit | 41b38b6d540f951c49315d8573e6f6195a6e736d (patch) | |
| tree | e667cec0bba6e7678810ff0087c96547a21a45c7 /block/blk-throttle.c | |
| parent | 629ed0b10209ffc4e1d439e5508d52d5e3a090b8 (diff) | |
| download | blackbird-op-linux-41b38b6d540f951c49315d8573e6f6195a6e736d.tar.gz blackbird-op-linux-41b38b6d540f951c49315d8573e6f6195a6e736d.zip | |
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 <tj@kernel.org>
Diffstat (limited to 'block/blk-throttle.c')
| -rw-r--r-- | block/blk-throttle.c | 31 |
1 files changed, 30 insertions, 1 deletions
diff --git a/block/blk-throttle.c b/block/blk-throttle.c index 5d647edc02a1..cb259bc46f43 100644 --- a/block/blk-throttle.c +++ b/block/blk-throttle.c @@ -582,7 +582,6 @@ static void throtl_update_dispatch_stats(struct blkio_group *blkg, u64 bytes, stats_cpu = this_cpu_ptr(pd->stats_cpu); - blkg_stat_add(&stats_cpu->sectors, bytes >> 9); blkg_rwstat_add(&stats_cpu->serviced, rw, 1); blkg_rwstat_add(&stats_cpu->service_bytes, rw, bytes); @@ -843,6 +842,36 @@ static void throtl_update_blkio_group_common(struct throtl_data *td, throtl_schedule_delayed_work(td, 0); } +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_rwstat specified by BLKCG_STAT_PRIV() */ +static 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; +} + static u64 blkg_prfill_conf_u64(struct seq_file *sf, struct blkg_policy_data *pd, int off) { |
