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McKenney" , rcu@vger.kernel.org, Steven Rostedt , "Uladzislau Rezki (Sony)" , fweisbec@gmail.com, neeraj.iitr10@gmail.com Subject: [PATCH v7 5/6] rcu/tree: Remove redundant smp_mb() in rcu_do_batch Date: Wed, 14 Oct 2020 20:23:00 -0400 Message-Id: <20201015002301.101830-6-joel@joelfernandes.org> X-Mailer: git-send-email 2.28.0.1011.ga647a8990f-goog In-Reply-To: <20201015002301.101830-1-joel@joelfernandes.org> References: <20201015002301.101830-1-joel@joelfernandes.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This memory barrier is not needed as rcu_segcblist_add_len() already includes a memory barrier. Signed-off-by: Joel Fernandes (Google) --- kernel/rcu/tree.c | 1 - 1 file changed, 1 deletion(-) diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 346a05506935..6c6d3c7036e6 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -2525,7 +2525,6 @@ static void rcu_do_batch(struct rcu_data *rdp) /* Update counts and requeue any remaining callbacks. */ rcu_segcblist_insert_done_cbs(&rdp->cblist, &rcl); - smp_mb(); /* List handling before counting for rcu_barrier(). */ rcu_segcblist_add_len(&rdp->cblist, -count); /* Reinstate batch limit if we have worked down the excess. */ -- 2.28.0.1011.ga647a8990f-goog