[PATCH 4/6] bdi: Use irqsave variant of refcount_dec_and_lock()

[Sebastian Andrzej Siewior]

From: Anna-Maria Gleixner <anna-maria@xxxxxxxxxxxxx>

The irqsave variant of refcount_dec_and_lock handles irqsave/restore when
taking/releasing the spin lock. With this variant the call of
local_irq_save/restore is no longer required.

Cc: linux-mm@xxxxxxxxx
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Signed-off-by: Anna-Maria Gleixner <anna-maria@xxxxxxxxxxxxx>
[bigeasy: s@atomic_dec_and_lock@refcount_dec_and_lock@g ]
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
---
 mm/backing-dev.c | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/mm/backing-dev.c b/mm/backing-dev.c
index 55a233d75f39..f5981e9d6ae2 100644
--- a/mm/backing-dev.c
+++ b/mm/backing-dev.c
@@ -473,11 +473,8 @@ void wb_congested_put(struct bdi_writeback_congested *congested)
 {
 	unsigned long flags;
 
-	local_irq_save(flags);
-	if (!refcount_dec_and_lock(&congested->refcnt, &cgwb_lock)) {
-		local_irq_restore(flags);
+	if (!refcount_dec_and_lock_irqsave(&congested->refcnt, &cgwb_lock, &flags))
 		return;
-	}
 
 	/* bdi might already have been destroyed leaving @congested unlinked */
 	if (congested->__bdi) {
-- 
2.18.0