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 442FE12FB12; Thu, 7 Mar 2024 18:58:40 +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=1709837921; cv=none; b=jOmjcYSe6ff0K9tqJXSynWY8Cq+bdBaoX8OTujW1yoDoYcrrw4fADeMIOsWQxvAK6U6rVobfLzq3rIhRtpDEdtJhOPo0vGHcTq2QmHZx1d9/bMvUDOmHtiVaVcJ0OekCIC8y9LXCzrfdT1JwqS5M+C09UbtXDPnbVjfDvxkCpZM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709837921; c=relaxed/simple; bh=XrTXKV4fLLNZYeQ7K7P7tCKsNgQbgRtB2hmD8awyd7s=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=EbK8xj0Lb1w/ekv8yPRF7Jrc4A1MoDBaTehgQRf6I9iwquc+d9XLztCD/LlYJqa9oJSjkED2PWylJn7Fv1CzutyKt7lTgEI7Wmj1iLnFloDOJcBt/1cLRR951QkXZU6jrnZCgEQrK9FImOhYkm0ElMdjKkhFUV6gSrHVWuHVV7A= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=T4IgkS67; 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="T4IgkS67" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C7792C433F1; Thu, 7 Mar 2024 18:58:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1709837920; bh=XrTXKV4fLLNZYeQ7K7P7tCKsNgQbgRtB2hmD8awyd7s=; h=Date:From:To:Cc:Subject:Reply-To:References:In-Reply-To:From; b=T4IgkS67qBXEryQUh1eyup04KKujuTcp1GpBVVC8GTfw7LhnS5cRcPmPxqiYX341X 5QFzU5lVrQ12kfVjLceTo3j8L6pU1zxiiPM8ac8By9WBUnXdHr2MpO/YPOgfmLW3Cg ySkH7HplOBQpDXuSLQIgHouMTqeZ75dIiRrQ/U8AyBMQwSgq+0+ZNWNCq1UOpTSv4z pgh8FfKFzUQkrpM0mR58q4YLajIQA/XLGBeHqyV5n+zpgKQp/1o5jRYHPnc/GFvo/I cdvMvgqqMb8mPX1Q0pHfQ/RaDywZ3kQN3a4Q5iLAWl7XgBdj/u0ajJkvksWhg/rFT/ X0KQ1Dfs8MAlQ== Received: by paulmck-ThinkPad-P17-Gen-1.home (Postfix, from userid 1000) id 5C49ACE0716; Thu, 7 Mar 2024 10:58:40 -0800 (PST) Date: Thu, 7 Mar 2024 10:58:40 -0800 From: "Paul E. McKenney" To: Steven Rostedt Cc: Mark Rutland , Joel Fernandes , Network Development , LKML , rcu@vger.kernel.org, kernel-team Subject: Re: [PATCH] net: raise RCU qs after each threaded NAPI poll Message-ID: <1165c893-b812-4f88-a1d6-fff85592657e@paulmck-laptop> Reply-To: paulmck@kernel.org References: <55900c6a-f181-4c5c-8de2-bca640c4af3e@paulmck-laptop> <10FC3F5F-AA33-4F81-9EB6-87EB2D41F3EE@joelfernandes.org> <99b2ccae-07f6-4350-9c55-25ec7ae065c0@paulmck-laptop> <20240307135215.7ba88d83@gandalf.local.home> 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=us-ascii Content-Disposition: inline In-Reply-To: <20240307135215.7ba88d83@gandalf.local.home> On Thu, Mar 07, 2024 at 01:52:15PM -0500, Steven Rostedt wrote: > On Thu, 7 Mar 2024 16:57:33 +0000 > Mark Rutland wrote: > > > * Use rcu_tasks_trace to synchronize updates? > > Yes. I think I wanted both. The above to make sure it covers all cases > where something could be preempted, and a case for those covered when RCU > isn't watching (which always has preemption disabled). > > My mistake was I thought synchronize_rcu_tasks_rude() did both. But I just > found out recently that it is not a superset of synchronize_rcu_tasks(). > > But it really needs it in every location that synchronize_rcu_tasks_rude() > is called. Should any RCU Tasks Rude grace-period request also wait for an RCU Tasks grace period? I would feel better about proposing this, especially for call_rcu_tasks_rude(), if RCU Tasks Rude was not supposed to be going away after all the noinstr tags are in place. Thanx, Paul