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From: tada keisuke <keisuke1.tada@kioxia.com>
To: "song@kernel.org" <song@kernel.org>,
        "yukuai3@huawei.com"
	<yukuai3@huawei.com>
CC: "linux-raid@vger.kernel.org" <linux-raid@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: [PATCH 09/11] md: add atomic mode switching when removing disk
Thread-Topic: [PATCH 09/11] md: add atomic mode switching when removing disk
Thread-Index: Adp/ZIq7EnQH8Y/+QBWXhs+ct+FbWA==
Date: Tue, 26 Mar 2024 10:29:47 +0000
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This patch depends on patch 08.

To minimize the number of execution of atomic mode switching, not only addi=
ng atomic mode switching, but also remove judgment is divided into two stag=
es.
Latency is minimized because only rdev to be removed is switched to atomic =
mode, not all rdevs.

Signed-off-by: Keisuke TADA <keisuke1.tada@kioxia.com>
Signed-off-by: Toshifumi OHTAKE <toshifumi.ootake@kioxia.com>
---
 drivers/md/md.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 30fbba38ea58..8c0c48a3a585 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -9277,8 +9277,10 @@ static bool rdev_removeable(struct md_rdev *rdev)
 		return false;
=20
 	/* Fautly rdev is not used, it's safe to remove it. */
-	if (test_bit(Faulty, &rdev->flags))
+	if (test_bit(Faulty, &rdev->flags)) {
+		percpu_ref_switch_to_atomic_sync(&rdev->nr_pending);
 		return true;
+	}
=20
 	/* Journal disk can only be removed if it's faulty. */
 	if (test_bit(Journal, &rdev->flags))
--=20
2.34.1