From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D962DC2D0E8 for ; Sat, 28 Mar 2020 23:43:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AD59520748 for ; Sat, 28 Mar 2020 23:43:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1585438989; bh=8F71ls7LTfaSvQwEnfaxYVz5lj1N1vsQKt2LOAk29EQ=; h=Date:From:To:Cc:Subject:Reply-To:References:In-Reply-To:List-ID: From; b=QE/XND6n9jbRutRg8ORR1oA/dNcs2eUgv1AluaGMFUTFrpByf8RTq8Cp8gDJwW8fi 3tvxUnYTUYhMJT4Gw0UCumpbiAWR5jAO/qdn4DYkUZo8uIB0/5jOjdwV9brzMoQjzZ +5iQ/EFqtt7jDIDUlSyH6KF2sxQZjr84vR5VEHM8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727701AbgC1XnI (ORCPT ); Sat, 28 Mar 2020 19:43:08 -0400 Received: from mail.kernel.org ([198.145.29.99]:41314 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726604AbgC1XnH (ORCPT ); Sat, 28 Mar 2020 19:43:07 -0400 Received: from paulmck-ThinkPad-P72.home (50-39-105-78.bvtn.or.frontiernet.net [50.39.105.78]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 1555920716; Sat, 28 Mar 2020 23:43:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1585438987; bh=8F71ls7LTfaSvQwEnfaxYVz5lj1N1vsQKt2LOAk29EQ=; h=Date:From:To:Cc:Subject:Reply-To:References:In-Reply-To:From; b=zWqeW4Byiv022nOtsnEbub+KQiNfiX4TOzaJ6hxmErzytUkabLE/2P9exka8iqCHN SPWVGFClHCkP6cjo2UcQfAb4cdsKf5ARgo/kGQ85eNQiQfjuLkDAcwW8laqylZYJT/ RtS8GRPH5BHMybeHXQD3p4LJAjcsBwZ04ud9Bpac= Received: by paulmck-ThinkPad-P72.home (Postfix, from userid 1000) id 979A83522755; Sat, 28 Mar 2020 16:43:06 -0700 (PDT) Date: Sat, 28 Mar 2020 16:43:06 -0700 From: "Paul E. McKenney" To: "Joel Fernandes (Google)" Cc: linux-kernel@vger.kernel.org, Andy Lutomirski , Frederic Weisbecker , frextrite@gmail.com, Ingo Molnar , Josh Triplett , kernel-team@android.com, Lai Jiangshan , madhuparnabhowmik04@gmail.com, Mathieu Desnoyers , peterz@infradead.org, Petr Mladek , rcu@vger.kernel.org, rostedt@goodmis.org, tglx@linutronix.de, vpillai@digitalocean.com Subject: Re: [PATCH v2 0/4] RCU dyntick nesting counter cleanups Message-ID: <20200328234306.GC19865@paulmck-ThinkPad-P72> Reply-To: paulmck@kernel.org References: <20200328221703.48171-1-joel@joelfernandes.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200328221703.48171-1-joel@joelfernandes.org> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Mar 28, 2020 at 06:16:59PM -0400, Joel Fernandes (Google) wrote: > These patches clean up the usage of dynticks nesting counters simplifying the > code, while preserving the usecases. > > It is a much needed simplification, makes the code less confusing, and prevents > future bugs such as those that arise from forgetting that the > dynticks_nmi_nesting counter is not a simple counter and can be "crowbarred" in > common situations. > > rcutorture testing with all TREE RCU configurations succeed with > CONFIG_RCU_EQS_DEBUG=y and CONFIG_PROVE_LOCKING=y. Heh! We now have a three-way collision between Thomas's and Peter's series, the RCU Tasks Trace series, and this series. ;-) Remind me once v5.7-rc1 comes out and let's see what fits where. Thanx, Paul > v1->v2: > - Rebase on v5.6-rc6 > > Joel Fernandes (Google) (4): > Revert b8c17e6664c4 ("rcu: Maintain special bits at bottom of > ->dynticks counter") > rcu/tree: Add better tracing for dyntick-idle > rcu/tree: Clean up dynticks counter usage > rcu/tree: Remove dynticks_nmi_nesting counter > > .../Data-Structures/Data-Structures.rst | 31 +-- > Documentation/RCU/stallwarn.txt | 6 +- > include/linux/rcutiny.h | 3 - > include/trace/events/rcu.h | 29 +-- > kernel/rcu/rcu.h | 4 - > kernel/rcu/tree.c | 188 +++++++----------- > kernel/rcu/tree.h | 4 +- > kernel/rcu/tree_stall.h | 4 +- > 8 files changed, 105 insertions(+), 164 deletions(-) > > -- > 2.26.0.rc2.310.g2932bb562d-goog >