diff options
| -rw-r--r-- | block/blk-cgroup.c | 19 |
1 files changed, 18 insertions, 1 deletions
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index 52367a4501d0..37e6cc91d576 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -322,6 +322,7 @@ static struct blkcg_gq *blkg_alloc(struct blkcg *blkcg, struct gendisk *disk, blkg->q = disk->queue; INIT_LIST_HEAD(&blkg->q_node); blkg->blkcg = blkcg; + blkg->iostat.blkg = blkg; #ifdef CONFIG_BLK_CGROUP_PUNT_BIO spin_lock_init(&blkg->async_bio_lock); bio_list_init(&blkg->async_bios); @@ -1046,6 +1047,8 @@ static void __blkcg_rstat_flush(struct blkcg *blkcg, int cpu) smp_mb(); WRITE_ONCE(bisc->lqueued, false); + if (bisc == &blkg->iostat) + goto propagate_up; /* propagate up to parent only */ /* fetch the current per-cpu values */ do { @@ -1055,10 +1058,24 @@ static void __blkcg_rstat_flush(struct blkcg *blkcg, int cpu) blkcg_iostat_update(blkg, &cur, &bisc->last); +propagate_up: /* propagate global delta to parent (unless that's root) */ - if (parent && parent->parent) + if (parent && parent->parent) { blkcg_iostat_update(parent, &blkg->iostat.cur, &blkg->iostat.last); + /* + * Queue parent->iostat to its blkcg's lockless + * list to propagate up to the grandparent if the + * iostat hasn't been queued yet. + */ + if (!parent->iostat.lqueued) { + struct llist_head *plhead; + + plhead = per_cpu_ptr(parent->blkcg->lhead, cpu); + llist_add(&parent->iostat.lnode, plhead); + parent->iostat.lqueued = true; + } + } } raw_spin_unlock_irqrestore(&blkg_stat_lock, flags); out: |