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McKenney" , Neeraj Upadhyay , Joel Fernandes , Josh Triplett , Steven Rostedt , Mathieu Desnoyers , Lai Jiangshan , Zqiang Subject: Re: [PATCH 1/8] rcu/exp: Remove full barrier upon main thread wakeup Message-ID: References: <20240129232349.3170819-1-boqun.feng@gmail.com> <20240129232349.3170819-2-boqun.feng@gmail.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Le Tue, Jan 30, 2024 at 04:47:16PM +0100, Frederic Weisbecker a ?crit : > Le Mon, Jan 29, 2024 at 03:23:39PM -0800, Boqun Feng a ?crit : > > From: Frederic Weisbecker > > > > When an expedited grace period is ending, care must be taken so that all > > the quiescent states propagated up to the root are correctly ordered > > against the wake up of the main expedited grace period workqueue. > > > > This ordering is already carried through the root rnp locking augmented > > by an smp_mb__after_unlock_lock() barrier. > > > > Therefore the explicit smp_mb() placed before the wake up is not needed > > and can be removed. > > > > Signed-off-by: Frederic Weisbecker > > Signed-off-by: Paul E. McKenney > > [Offlist] And yes that was not offlist, my fingers betrayed me! > > For further posting, don't forget to add your own SoB while posting patches :-) > > Thanks! >