dm thin: wake worker when discard is prepared

When discards are prepared it is best to directly wake the worker that will process them. The worker will be woken anyway, via periodic commit, but there is no reason to not wake_worker here. Signed-off-by: Joe Thornber <[email protected]> Signed-off-by: Mike Snitzer <[email protected]> Signed-off-by: Alasdair G Kergon <[email protected]>
cbmeeks · Dec 21, 2012 · 563af18 · 563af18
1 parent e808807
commit 563af18
Showing 1 changed file with 7 additions and 4 deletions.
diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c
@@ -2676,10 +2676,13 @@ static int thin_endio(struct dm_target *ti,
 	if (h->all_io_entry) {
 		INIT_LIST_HEAD(&work);
 		dm_deferred_entry_dec(h->all_io_entry, &work);
-		spin_lock_irqsave(&pool->lock, flags);
-		list_for_each_entry_safe(m, tmp, &work, list)
-			list_add(&m->list, &pool->prepared_discards);
-		spin_unlock_irqrestore(&pool->lock, flags);
+		if (!list_empty(&work)) {
+			spin_lock_irqsave(&pool->lock, flags);
+			list_for_each_entry_safe(m, tmp, &work, list)
+				list_add(&m->list, &pool->prepared_discards);
+			spin_unlock_irqrestore(&pool->lock, flags);
+			wake_worker(pool);
+		}
 	}
 
 	mempool_free(h, pool->endio_hook_pool);