Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To:     linux-kernel@vger.kernel.org
Cc:     tglx@linutronix.de, Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@kernel.org>,
        Anna-Maria Gleixner <anna-maria@linutronix.de>,
        linux-mm@kvack.org, Andrew Morton <akpm@linux-foundation.org>,
        Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Subject: [PATCH 4/6] bdi: Use irqsave variant of refcount_dec_and_lock()
Date:   Tue,  3 Jul 2018 22:01:39 +0200
Message-Id: <20180703200141.28415-5-bigeasy@linutronix.de>
In-Reply-To: <20180703200141.28415-1-bigeasy@linutronix.de>
References: <20180703200141.28415-1-bigeasy@linutronix.de>
MIME-Version: 1.0
Content-Transfer-Encoding: quoted-printable
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

From: Anna-Maria Gleixner <anna-maria@linutronix.de>

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@kvack.org
Cc: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
[bigeasy: s@atomic_dec_and_lock@refcount_dec_and_lock@g ]
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
 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;
=20
-	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;
-	}
=20
 	/* bdi might already have been destroyed leaving @congested unlinked */
 	if (congested->__bdi) {
--=20
2.18.0