io-wq: reduce acct->lock crossing functions lock/unlock

reduce acct->lock lock and unlock in different functions to make the
code clearer.

Signed-off-by: Hao Xu <haoxu@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220206095241.121485-3-haoxu@linux.alibaba.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/fs/io-wq.c b/fs/io-wq.c
index 9595616ccaa3cf37f226c09da4bb6db58e529b38..f7b7fa396fafce16fbb51538b843fca5060c4830 100644 (file)
--- a/fs/io-wq.c
+++ b/fs/io-wq.c
@@ -239,10 +239,15 @@ static void io_worker_exit(struct io_worker *worker)
 
 static inline bool io_acct_run_queue(struct io_wqe_acct *acct)
 {
+       bool ret = false;
+
+       raw_spin_lock(&acct->lock);
        if (!wq_list_empty(&acct->work_list) &&
            !test_bit(IO_ACCT_STALLED_BIT, &acct->flags))
-               return true;
-       return false;
+               ret = true;
+       raw_spin_unlock(&acct->lock);
+
+       return ret;
 }
 
 /*
@@ -395,13 +400,9 @@ static void io_wqe_dec_running(struct io_worker *worker)
 
        if (!atomic_dec_and_test(&acct->nr_running))
                return;
-       raw_spin_lock(&wqe->lock);
-       if (!io_acct_run_queue(acct)) {
-               raw_spin_unlock(&wqe->lock);
+       if (!io_acct_run_queue(acct))
                return;
-       }
 
-       raw_spin_unlock(&wqe->lock);
        atomic_inc(&acct->nr_running);
        atomic_inc(&wqe->wq->worker_refs);
        io_queue_worker_create(worker, acct, create_worker_cb);
@@ -544,7 +545,6 @@ static void io_assign_current_work(struct io_worker *worker,
 static void io_wqe_enqueue(struct io_wqe *wqe, struct io_wq_work *work);
 
 static void io_worker_handle_work(struct io_worker *worker)
-       __releases(acct->lock)
 {
        struct io_wqe_acct *acct = io_wqe_get_acct(worker);
        struct io_wqe *wqe = worker->wqe;
@@ -561,6 +561,7 @@ static void io_worker_handle_work(struct io_worker *worker)
                 * can't make progress, any work completion or insertion will
                 * clear the stalled flag.
                 */
+               raw_spin_lock(&acct->lock);
                work = io_get_next_work(acct, worker);
                raw_spin_unlock(&acct->lock);
                if (work) {
@@ -614,8 +615,6 @@ static void io_worker_handle_work(struct io_worker *worker)
                                        wake_up(&wq->hash->wait);
                        }
                } while (work);
-
-               raw_spin_lock(&acct->lock);
        } while (1);
 }
 
@@ -639,14 +638,9 @@ static int io_wqe_worker(void *data)
                long ret;
 
                set_current_state(TASK_INTERRUPTIBLE);
-loop:
-               raw_spin_lock(&acct->lock);
-               if (io_acct_run_queue(acct)) {
+               while (io_acct_run_queue(acct))
                        io_worker_handle_work(worker);
-                       goto loop;
-               } else {
-                       raw_spin_unlock(&acct->lock);
-               }
+
                raw_spin_lock(&wqe->lock);
                /* timed out, exit unless we're the last worker */
                if (last_timeout && acct->nr_workers > 1) {
@@ -671,10 +665,8 @@ loop:
                last_timeout = !ret;
        }
 
-       if (test_bit(IO_WQ_BIT_EXIT, &wq->state)) {
-               raw_spin_lock(&acct->lock);
+       if (test_bit(IO_WQ_BIT_EXIT, &wq->state))
                io_worker_handle_work(worker);
-       }
 
        audit_free(current);
        io_worker_exit(worker);