btrfs: merge critical sections of discard lock in workfn

btrfs_discard_workfn() drops discard_ctl->lock just to take it again in
a moment in btrfs_discard_schedule_work(). Avoid that and also reuse
ktime.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/discard.c b/fs/btrfs/discard.c
index d641f451f8405b298380858790a4ff685b096660..2b8383d4114490bcc162f174a95ff1d6b2ef79e1 100644 (file)
--- a/fs/btrfs/discard.c
+++ b/fs/btrfs/discard.c
@@ -328,28 +328,15 @@ void btrfs_discard_queue_work(struct btrfs_discard_ctl *discard_ctl,
                btrfs_discard_schedule_work(discard_ctl, false);
 }
 
-/**
- * btrfs_discard_schedule_work - responsible for scheduling the discard work
- * @discard_ctl: discard control
- * @override: override the current timer
- *
- * Discards are issued by a delayed workqueue item.  @override is used to
- * update the current delay as the baseline delay interval is reevaluated on
- * transaction commit.  This is also maxed with any other rate limit.
- */
-void btrfs_discard_schedule_work(struct btrfs_discard_ctl *discard_ctl,
-                                bool override)
+static void __btrfs_discard_schedule_work(struct btrfs_discard_ctl *discard_ctl,
+                                         u64 now, bool override)
 {
        struct btrfs_block_group *block_group;
-       const u64 now = ktime_get_ns();
-
-       spin_lock(&discard_ctl->lock);
 
        if (!btrfs_run_discard_work(discard_ctl))
-               goto out;
-
+               return;
        if (!override && delayed_work_pending(&discard_ctl->work))
-               goto out;
+               return;
 
        block_group = find_next_block_group(discard_ctl, now);
        if (block_group) {
@@ -391,7 +378,24 @@ void btrfs_discard_schedule_work(struct btrfs_discard_ctl *discard_ctl,
                mod_delayed_work(discard_ctl->discard_workers,
                                 &discard_ctl->work, nsecs_to_jiffies(delay));
        }
-out:
+}
+
+/*
+ * btrfs_discard_schedule_work - responsible for scheduling the discard work
+ * @discard_ctl:  discard control
+ * @override:     override the current timer
+ *
+ * Discards are issued by a delayed workqueue item.  @override is used to
+ * update the current delay as the baseline delay interval is reevaluated on
+ * transaction commit.  This is also maxed with any other rate limit.
+ */
+void btrfs_discard_schedule_work(struct btrfs_discard_ctl *discard_ctl,
+                                bool override)
+{
+       const u64 now = ktime_get_ns();
+
+       spin_lock(&discard_ctl->lock);
+       __btrfs_discard_schedule_work(discard_ctl, now, override);
        spin_unlock(&discard_ctl->lock);
 }
 
@@ -497,9 +501,8 @@ static void btrfs_discard_workfn(struct work_struct *work)
        discard_ctl->prev_discard = trimmed;
        discard_ctl->prev_discard_time = now;
        discard_ctl->block_group = NULL;
+       __btrfs_discard_schedule_work(discard_ctl, now, false);
        spin_unlock(&discard_ctl->lock);
-
-       btrfs_discard_schedule_work(discard_ctl, false);
 }
 
 /**