diff options
Diffstat (limited to 'block')
| -rw-r--r-- | block/blk-cgroup.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index 8699f193cf31..52367a4501d0 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -1035,6 +1035,16 @@ static void __blkcg_rstat_flush(struct blkcg *blkcg, int cpu) struct blkg_iostat cur; unsigned int seq; + /* + * Order assignment of `next_bisc` from `bisc->lnode.next` in + * llist_for_each_entry_safe and clearing `bisc->lqueued` for + * avoiding to assign `next_bisc` with new next pointer added + * in blk_cgroup_bio_start() in case of re-ordering. + * + * The pair barrier is implied in llist_add() in blk_cgroup_bio_start(). + */ + smp_mb(); + WRITE_ONCE(bisc->lqueued, false); /* fetch the current per-cpu values */ |