From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id F32486A32D; Tue, 30 Jan 2024 15:48:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706629725; cv=none; b=SEjGAt9fj2Y4MptGW1mP8wyC94u6BdFxQfLzHMO35FlsjH9oFgQuEtTEgS9z75RhgQMXYi+rLwCzQ1ML40dtT9c/7RaxYa7MDTrZ6ofysrzI7Dfv8q3vorBsnCIrlYXo33/9NdO1hiAFTvQ7nQVa0RMVzKH3yW5z6r3M5CY6RYM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706629725; c=relaxed/simple; bh=yTujMnql4yUMoznvweOoKBZMoA56VqLnJzwfD5oRz4s=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=No91CywcAO4QA3Q52BDD5Z865tyFqQ+rcwvBpWH4u4yonu4YRLImjGo0rIQ0vQnq1yq89UtzPBi374t8stm2IAqvwzNgIyMSsu9zQexiHK3T6njbJkKyPvzJsqfPg/K2zbyEfQlIVaRqijfzg1Kos7mFBttQd+BYvDlAwWIE9BM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=lUS5fZ58; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="lUS5fZ58" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1C6EEC433C7; Tue, 30 Jan 2024 15:48:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1706629724; bh=yTujMnql4yUMoznvweOoKBZMoA56VqLnJzwfD5oRz4s=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=lUS5fZ58kdH7Ue/vpJzExyh9NPNINmBBRVTB8leklIHb9m7ocPsDE7B+FMOXGsmk8 iv/5s3LSC6JGOSQlJR+mcWfwBWBs7EK2fyDLm7BorgPsE0NiFkSXgxY6tzbVdTQiW3 Jvghi1vX+bwCCscsHDrzChvzctsFqkY7BRAWQJzUAwTGsvwyqZtPBTEa8WNxcs0yEO GLfKc7CyiLEojwb1iOFByB4qMuSgu1tsj5AMR9Yg0R8E/MfXPHcZ7YD4Wx9UMeZNSZ 4HySbmInYgcgeUlcrCKWKTqHPEKpq7cQ38Z0icnWmeAJ8+7mgNaCvqnMON8yk0GViP CA9Ii6T6XRjrQ== Date: Tue, 30 Jan 2024 16:48:41 +0100 From: Frederic Weisbecker To: Boqun Feng Cc: linux-kernel@vger.kernel.org, rcu@vger.kernel.org, "Paul E . 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: rcu@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 écrit : > Le Mon, Jan 29, 2024 at 03:23:39PM -0800, Boqun Feng a écrit : > > 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! >