diff options
| -rw-r--r-- | fs/fs-writeback.c | 17 | ||||
| -rw-r--r-- | mm/backing-dev.c | 12 |
2 files changed, 20 insertions, 9 deletions
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c index 9958d4020771..aa33c39be182 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -974,6 +974,16 @@ restart: continue; } + /* + * If wb_tryget fails, the wb has been shutdown, skip it. + * + * Pin @wb so that it stays on @bdi->wb_list. This allows + * continuing iteration from @wb after dropping and + * regrabbing rcu read lock. + */ + if (!wb_tryget(wb)) + continue; + /* alloc failed, execute synchronously using on-stack fallback */ work = &fallback_work; *work = *base_work; @@ -982,13 +992,6 @@ restart: work->done = &fallback_work_done; wb_queue_work(wb, work); - - /* - * Pin @wb so that it stays on @bdi->wb_list. This allows - * continuing iteration from @wb after dropping and - * regrabbing rcu read lock. - */ - wb_get(wb); last_wb = wb; rcu_read_unlock(); diff --git a/mm/backing-dev.c b/mm/backing-dev.c index c30419a5e119..bf5525c2e561 100644 --- a/mm/backing-dev.c +++ b/mm/backing-dev.c @@ -380,6 +380,15 @@ static LIST_HEAD(offline_cgwbs); static void cleanup_offline_cgwbs_workfn(struct work_struct *work); static DECLARE_WORK(cleanup_offline_cgwbs_work, cleanup_offline_cgwbs_workfn); +static void cgwb_free_rcu(struct rcu_head *rcu_head) +{ + struct bdi_writeback *wb = container_of(rcu_head, + struct bdi_writeback, rcu); + + percpu_ref_exit(&wb->refcnt); + kfree(wb); +} + static void cgwb_release_workfn(struct work_struct *work) { struct bdi_writeback *wb = container_of(work, struct bdi_writeback, @@ -402,11 +411,10 @@ static void cgwb_release_workfn(struct work_struct *work) list_del(&wb->offline_node); spin_unlock_irq(&cgwb_lock); - percpu_ref_exit(&wb->refcnt); wb_exit(wb); bdi_put(bdi); WARN_ON_ONCE(!list_empty(&wb->b_attached)); - kfree_rcu(wb, rcu); + call_rcu(&wb->rcu, cgwb_free_rcu); } static void cgwb_release(struct percpu_ref *refcnt) |