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McKenney" , Peter Zijlstra , Steven Rostedt Subject: [PATCH RFC 1/2] sched/core: Convert synchronize_rcu_mult to synchronize_rcu Date: Mon, 1 Oct 2018 18:20:11 -0700 Message-Id: <20181002012012.13133-1-joel@joelfernandes.org> X-Mailer: git-send-email 2.19.0.605.g01d371f741-goog MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: "Joel Fernandes (Google)" synchronize_rcu_mult is now obsolete since all the different RCU flavors have been consolidated and the API is now common on the updater side. sched/core.c is the only user of it. All call_rcu_ calls boil down to the same call_rcu. So there's no point in calling synchronize_rcu_mult infact it could potentially be slower due to waiting for the call_rcu callback twice. Just call synchronize_rcu here which should do the job. Signed-off-by: Joel Fernandes (Google) --- kernel/sched/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 625bc9897f62..d8311f3cf58c 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -5791,7 +5791,7 @@ int sched_cpu_deactivate(unsigned int cpu) * * Do sync before park smpboot threads to take care the rcu boost case. */ - synchronize_rcu_mult(call_rcu, call_rcu_sched); + synchronize_rcu(); if (!sched_smp_initialized) return 0; -- 2.19.0.605.g01d371f741-goog