linux-kernel - [PATCH RESEND] ext4: Switch to kvfree

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Message-Id: <20211215111845.2514-3-urezki@gmail.com>
Date:   Wed, 15 Dec 2021 12:18:39 +0100
From:   "Uladzislau Rezki (Sony)" <urezki@...il.com>
To:     LKML <linux-kernel@...r.kernel.org>, RCU <rcu@...r.kernel.org>,
        "Paul E . McKenney" <paulmck@...nel.org>
Cc:     Michal Hocko <mhocko@...e.com>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Daniel Axtens <dja@...ens.net>,
        Frederic Weisbecker <frederic@...nel.org>,
        Neeraj Upadhyay <neeraju@...eaurora.org>,
        Joel Fernandes <joel@...lfernandes.org>,
        Peter Zijlstra <peterz@...radead.org>,
        Thomas Gleixner <tglx@...utronix.de>,
        "Theodore Y . Ts'o" <tytso@....edu>,
        Sebastian Andrzej Siewior <bigeasy@...utronix.de>,
        Uladzislau Rezki <urezki@...il.com>,
        Oleksiy Avramchenko <oleksiy.avramchenko@...ymobile.com>,
        Uladzislau Rezki <uladzislau.rezki@...y.com>
Subject: [PATCH RESEND] ext4: Switch to kvfree_rcu() API

From: Uladzislau Rezki <uladzislau.rezki@...y.com>

Instead of invoking a synchronize_rcu() to free a pointer
after a grace period we can directly make use of new API
that does the same but in more efficient way.

TO: "Theodore Ts'o" <tytso@....edu>
TO: linux-ext4@...r.kernel.org
Signed-off-by: Uladzislau Rezki <uladzislau.rezki@...y.com>
---
 fs/ext4/super.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 4e33b5eca694..111b0498a232 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1886,8 +1886,7 @@ static int clear_qf_name(struct super_block *sb, int qtype)
 		return -1;
 	}
 	rcu_assign_pointer(sbi->s_qf_names[qtype], NULL);
-	synchronize_rcu();
-	kfree(old_qname);
+	kvfree_rcu(old_qname);
 	return 1;
 }
 #endif
-- 
2.30.2