diff --git a/fs/io-wq.c b/fs/io-wq.c index afd955d53db9..88202de519f6 100644 --- a/fs/io-wq.c +++ b/fs/io-wq.c @@ -423,9 +423,10 @@ static inline unsigned int io_get_work_hash(struct io_wq_work *work) return work->flags >> IO_WQ_HASH_SHIFT; } -static void io_wait_on_hash(struct io_wqe *wqe, unsigned int hash) +static bool io_wait_on_hash(struct io_wqe *wqe, unsigned int hash) { struct io_wq *wq = wqe->wq; + bool ret = false; spin_lock_irq(&wq->hash->wait.lock); if (list_empty(&wqe->wait.entry)) { @@ -433,9 +434,11 @@ static void io_wait_on_hash(struct io_wqe *wqe, unsigned int hash) if (!test_bit(hash, &wq->hash->map)) { __set_current_state(TASK_RUNNING); list_del_init(&wqe->wait.entry); + ret = true; } } spin_unlock_irq(&wq->hash->wait.lock); + return ret; } static struct io_wq_work *io_get_next_work(struct io_wqe_acct *acct, @@ -475,14 +478,21 @@ static struct io_wq_work *io_get_next_work(struct io_wqe_acct *acct, } if (stall_hash != -1U) { + bool unstalled; + /* * Set this before dropping the lock to avoid racing with new * work being added and clearing the stalled bit. */ set_bit(IO_ACCT_STALLED_BIT, &acct->flags); raw_spin_unlock(&wqe->lock); - io_wait_on_hash(wqe, stall_hash); + unstalled = io_wait_on_hash(wqe, stall_hash); raw_spin_lock(&wqe->lock); + if (unstalled) { + clear_bit(IO_ACCT_STALLED_BIT, &acct->flags); + if (wq_has_sleeper(&wqe->wq->hash->wait)) + wake_up(&wqe->wq->hash->wait); + } } return NULL; @@ -564,8 +574,11 @@ get_next: io_wqe_enqueue(wqe, linked); if (hash != -1U && !next_hashed) { + /* serialize hash clear with wake_up() */ + spin_lock_irq(&wq->hash->wait.lock); clear_bit(hash, &wq->hash->map); clear_bit(IO_ACCT_STALLED_BIT, &acct->flags); + spin_unlock_irq(&wq->hash->wait.lock); if (wq_has_sleeper(&wq->hash->wait)) wake_up(&wq->hash->wait); raw_spin_lock(&wqe->lock);