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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 51282C3815B for ; Wed, 15 Apr 2020 17:31:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 322F22076D for ; Wed, 15 Apr 2020 17:31:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586971880; bh=x/pRCLer6rp72HqNGGnkhkYJNBCXT47lhuBfzel1ReA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=jAaradDOiAyBajHBBYYS6VxT4aMwTySTLJfesvdo5+46GgzXPK7rgF3yvIQfDs9mh x/zH3TZUIgOa+O7Ve1u5SwhuVuBCs2IScGCgRtiID5sxM72gSSG+lv/IOocFCmGN8R AJjQsOlbw9d8eOV71AE2Rt+CMSLionAhcQ9lC+ps= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2411153AbgDORbT (ORCPT ); Wed, 15 Apr 2020 13:31:19 -0400 Received: from mail.kernel.org ([198.145.29.99]:45874 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2411119AbgDORbE (ORCPT ); Wed, 15 Apr 2020 13:31:04 -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-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 33E2121582; Wed, 15 Apr 2020 17:31:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586971863; bh=x/pRCLer6rp72HqNGGnkhkYJNBCXT47lhuBfzel1ReA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=JRaME366xHhkbOa4vrmnf8LgP30PHZEkKj7TQTE3z4oFc8Zfj3fQbINwQRqRyPF7L 9208qVZHFcOK/sa6vEq6p9Sb9iZ7nj4wNXCHY7tc1O6vygLKdjcQrkHC4DBVbI3d9w 74Z59IYkC3L6wl1gv+trddZ8piR5hwo/qYaH1qxM= From: paulmck@kernel.org To: rcu@vger.kernel.org Cc: linux-kernel@vger.kernel.org, kernel-team@fb.com, mingo@kernel.org, jiangshanlai@gmail.com, dipankar@in.ibm.com, akpm@linux-foundation.org, mathieu.desnoyers@efficios.com, josh@joshtriplett.org, tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org, dhowells@redhat.com, edumazet@google.com, fweisbec@gmail.com, oleg@redhat.com, joel@joelfernandes.org, Madhuparna Bhowmik , Amol Grover , "Paul E . McKenney" Subject: [PATCH tip/core/rcu 05/18] Default enable RCU list lockdep debugging with PROVE_RCU Date: Wed, 15 Apr 2020 10:30:47 -0700 Message-Id: <20200415173100.9927-5-paulmck@kernel.org> X-Mailer: git-send-email 2.9.5 In-Reply-To: <20200415173037.GA9768@paulmck-ThinkPad-P72> References: <20200415173037.GA9768@paulmck-ThinkPad-P72> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Madhuparna Bhowmik This patch default enables CONFIG_PROVE_RCU_LIST option with CONFIG_PROVE_RCU for RCU list lockdep debugging. With this change, RCU list lockdep debugging will be default enabled in CONFIG_PROVE_RCU=y kernels. Most of the RCU users (in core kernel/, drivers/, and net/ subsystem) have already been modified to include lockdep expressions hence RCU list debugging can be enabled by default. However, there are still chances of enountering false-positive lockdep splats because not everything is converted, in case RCU list primitives are used in non-RCU read-side critical section but under the protection of a lock. It would be okay to have a few false-positives, as long as bugs are identified, since this patch only affects debugging kernels. Co-developed-by: Amol Grover Signed-off-by: Amol Grover Signed-off-by: Madhuparna Bhowmik Acked-by: Joel Fernandes (Google) Signed-off-by: Paul E. McKenney --- kernel/rcu/Kconfig.debug | 11 +++-------- 1 file changed, 3 insertions(+), 8 deletions(-) diff --git a/kernel/rcu/Kconfig.debug b/kernel/rcu/Kconfig.debug index 4aa02ee..ec4bb6c 100644 --- a/kernel/rcu/Kconfig.debug +++ b/kernel/rcu/Kconfig.debug @@ -9,15 +9,10 @@ config PROVE_RCU def_bool PROVE_LOCKING config PROVE_RCU_LIST - bool "RCU list lockdep debugging" - depends on PROVE_RCU && RCU_EXPERT - default n + def_bool PROVE_RCU help - Enable RCU lockdep checking for list usages. By default it is - turned off since there are several list RCU users that still - need to be converted to pass a lockdep expression. To prevent - false-positive splats, we keep it default disabled but once all - users are converted, we can remove this config option. + Enable RCU lockdep checking for list usages. It is default + enabled with CONFIG_PROVE_RCU. config TORTURE_TEST tristate -- 2.9.5