md/raid10: factor out code from wait_barrier() to stop_waiting_barrier()

Currently the nasty condition in wait_barrier() is hard to read. This
patch factors out the condition into a function.

There are no functional changes.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Acked-by: Paul Menzel <pmenzel@molgen.mpg.de>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Acked-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Signed-off-by: Song Liu <song@kernel.org>

diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index 077c7cd..310a613 100644 (file)
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -957,41 +957,47 @@ static void lower_barrier(struct r10conf *conf)
        wake_up(&conf->wait_barrier);
 }
 
+static bool stop_waiting_barrier(struct r10conf *conf)
+{
+       struct bio_list *bio_list = current->bio_list;
+
+       /* barrier is dropped */
+       if (!conf->barrier)
+               return true;
+
+       /*
+        * If there are already pending requests (preventing the barrier from
+        * rising completely), and the pre-process bio queue isn't empty, then
+        * don't wait, as we need to empty that queue to get the nr_pending
+        * count down.
+        */
+       if (atomic_read(&conf->nr_pending) && bio_list &&
+           (!bio_list_empty(&bio_list[0]) || !bio_list_empty(&bio_list[1])))
+               return true;
+
+       /* move on if recovery thread is blocked by us */
+       if (conf->mddev->thread->tsk == current &&
+           test_bit(MD_RECOVERY_RUNNING, &conf->mddev->recovery) &&
+           conf->nr_queued > 0)
+               return true;
+
+       return false;
+}
+
 static bool wait_barrier(struct r10conf *conf, bool nowait)
 {
        bool ret = true;
 
        spin_lock_irq(&conf->resync_lock);
        if (conf->barrier) {
-               struct bio_list *bio_list = current->bio_list;
                conf->nr_waiting++;
-               /* Wait for the barrier to drop.
-                * However if there are already pending
-                * requests (preventing the barrier from
-                * rising completely), and the
-                * pre-process bio queue isn't empty,
-                * then don't wait, as we need to empty
-                * that queue to get the nr_pending
-                * count down.
-                */
                /* Return false when nowait flag is set */
                if (nowait) {
                        ret = false;
                } else {
                        raid10_log(conf->mddev, "wait barrier");
                        wait_event_lock_irq(conf->wait_barrier,
-                                           !conf->barrier ||
-                                           (atomic_read(&conf->nr_pending) &&
-                                            bio_list &&
-                                            (!bio_list_empty(&bio_list[0]) ||
-                                             !bio_list_empty(&bio_list[1]))) ||
-                                            /* move on if recovery thread is
-                                             * blocked by us
-                                             */
-                                            (conf->mddev->thread->tsk == current &&
-                                             test_bit(MD_RECOVERY_RUNNING,
-                                                      &conf->mddev->recovery) &&
-                                             conf->nr_queued > 0),
+                                           stop_waiting_barrier(conf),
                                            conf->resync_lock);
                }
                conf->nr_waiting--;