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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 83ECAC10F14 for ; Thu, 18 Apr 2019 22:19:48 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 2499B217F9 for ; Thu, 18 Apr 2019 22:19:48 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2499B217F9 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id ACF7B6B0005; Thu, 18 Apr 2019 18:19:46 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id A7B9E6B0006; Thu, 18 Apr 2019 18:19:46 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8F94A6B0007; Thu, 18 Apr 2019 18:19:46 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from mail-pl1-f199.google.com (mail-pl1-f199.google.com [209.85.214.199]) by kanga.kvack.org (Postfix) with ESMTP id 529FB6B0005 for ; Thu, 18 Apr 2019 18:19:46 -0400 (EDT) Received: by mail-pl1-f199.google.com with SMTP id s22so2271151plq.1 for ; Thu, 18 Apr 2019 15:19:46 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-original-authentication-results:x-gm-message-state:date:from:to :cc:subject:message-id:in-reply-to:references:mime-version :content-transfer-encoding; bh=PjZi58gVreWv5Iuxlzjg5s/x6NQFE2omkHjhJQ21L0Y=; b=m/UbhIoVTDqfjiNFpIriqoxEILHv6DIniERZaMNjsvgHnRrEVMI1CNeWyQCYU1hDqt K4IhIPexh5jjgtoVngQNdIRQJ9NC/Zl+YW8wZxzO5QDozXLNTHLvjPjMa4koH3iKR7n9 o1qebr6rTzg9zHYq9Epym+8ZxvmgNhY31xSqrSjdMdZ2Cwl6eTIBRhKw1kBnq6Ywosv+ RpuSDADlZeKGVUZzgfQYj4ZxsPEpVJIqTozFWJ6MrsnvpvyOayhaFKn4Tw0UvlaqLiij q3tF8/SpTSiZKN1/Pcnmspzcvf5I2aLrTbdcEDuzzgkNEbvJ+Jk2MPtqBVCposc5uEpU 0xgQ== X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of srs0=+lpg=su=goodmis.org=rostedt@kernel.org designates 198.145.29.99 as permitted sender) smtp.mailfrom="SRS0=+LPG=SU=goodmis.org=rostedt@kernel.org" X-Gm-Message-State: APjAAAVVO2d/SsDpnSe9ccu84Uj9YJCeFvre2aeSk6UGODcgnrTam4rO BceBnE0qxye7wGv1vT9Y7CgFNFjQ1ienw/dZhHmiboJN0tY5t+2hwX8N/18hHfZM8rrp+5PMvOv cq4oVHjIuPixVe2PkW1vClQzq/dTKaI9HYNP0YSEgOXJqWtDnsm8uqjNf1IzJp+M= X-Received: by 2002:a65:5687:: with SMTP id v7mr351806pgs.299.1555625985933; Thu, 18 Apr 2019 15:19:45 -0700 (PDT) X-Google-Smtp-Source: APXvYqx5ZKw78dkVaqDbNBjt/M7LwtQvqJ0KLjy87TGub1WNAlgCRCCB0lFdMmaWnMAlUjdicxYg X-Received: by 2002:a65:5687:: with SMTP id v7mr351739pgs.299.1555625985081; Thu, 18 Apr 2019 15:19:45 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1555625985; cv=none; d=google.com; s=arc-20160816; b=sS3J/80QtqBgx1CpPaLJPj+NbUdehXm7SVkjY3z75iqj94H5QUCDIeIVUiz2tK7arm kD/ZFqMqxljX+gfIe0DdqRxNlOdHPy71b44O3wWx/+sJkd5PdAmZeA7CIdsAH/wok1wg /30iGao+z5AGasuw1M5Ws4hb/RN6usaSb01P4RfV4xX7rRbX0iTAyslSK2cZ2rilYMHq qzb+UZzu7/xfTXnGwF5JrHFZSiDmoIopNSPelZrF24Gcj+51/luovWFKHCAo7BWJS0dX awhwORExcg7HaJFDJCpBIiiVVoMiTCwgZV1oLLzlt3SWxNWkZd1fJYZtOb/O/BCePVyQ CBMQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:subject:cc:to:from:date; bh=PjZi58gVreWv5Iuxlzjg5s/x6NQFE2omkHjhJQ21L0Y=; b=bmZZnMTGV6tLS6xkbgTf3Yi98tTM+RoG3k8IlVTBhX5LG8vJsU21q2GxzWjuqVNqV5 fYimcDrjfHKSOBbVrrwA2aNW7KEdy1RkGLy95LkEGkfkRZEvNaQwwSup6EisIf/AFyA9 FKD9cPqKuJ3nVSETMyuGcD5jH0iPKfE/VtzrC2o0DfryD0SoPsUAhT2GCLG5Ab11Ttam tmwllIu8CQbADzf39wmn87WAI4ybNyFDQIXTmpuFlbAzIDZVKV5laqFMjWYC1MnWeet7 xFNs+hZZcdTnmKXMP03bob690uKTqMxOj/bNpjOVGECOO9RbR8vh2ABdZuikulkkY/8e dmOw== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of srs0=+lpg=su=goodmis.org=rostedt@kernel.org designates 198.145.29.99 as permitted sender) smtp.mailfrom="SRS0=+LPG=SU=goodmis.org=rostedt@kernel.org" Received: from mail.kernel.org (mail.kernel.org. [198.145.29.99]) by mx.google.com with ESMTPS id b23si3260256pls.430.2019.04.18.15.19.44 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 18 Apr 2019 15:19:44 -0700 (PDT) Received-SPF: pass (google.com: domain of srs0=+lpg=su=goodmis.org=rostedt@kernel.org designates 198.145.29.99 as permitted sender) client-ip=198.145.29.99; Authentication-Results: mx.google.com; spf=pass (google.com: domain of srs0=+lpg=su=goodmis.org=rostedt@kernel.org designates 198.145.29.99 as permitted sender) smtp.mailfrom="SRS0=+LPG=SU=goodmis.org=rostedt@kernel.org" Received: from gandalf.local.home (cpe-66-24-58-225.stny.res.rr.com [66.24.58.225]) (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 509352064A; Thu, 18 Apr 2019 22:19:41 +0000 (UTC) Date: Thu, 18 Apr 2019 18:19:38 -0400 From: Steven Rostedt To: Thomas Gleixner Cc: LKML , Josh Poimboeuf , x86@kernel.org, Andy Lutomirski , Alexander Potapenko , Alexey Dobriyan , Andrew Morton , Pekka Enberg , linux-mm@kvack.org, David Rientjes , Christoph Lameter , Catalin Marinas , Dmitry Vyukov , Andrey Ryabinin , kasan-dev@googlegroups.com, Mike Rapoport , Akinobu Mita , iommu@lists.linux-foundation.org, Robin Murphy , Christoph Hellwig , Marek Szyprowski , Johannes Thumshirn , David Sterba , Chris Mason , Josef Bacik , linux-btrfs@vger.kernel.org, dm-devel@redhat.com, Mike Snitzer , Alasdair Kergon , intel-gfx@lists.freedesktop.org, Joonas Lahtinen , Maarten Lankhorst , dri-devel@lists.freedesktop.org, David Airlie , Jani Nikula , Daniel Vetter , Rodrigo Vivi , linux-arch@vger.kernel.org Subject: Re: [patch V2 01/29] tracing: Cleanup stack trace code Message-ID: <20190418181938.2e2a9a04@gandalf.local.home> In-Reply-To: <20190418084253.142712304@linutronix.de> References: <20190418084119.056416939@linutronix.de> <20190418084253.142712304@linutronix.de> X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu, 18 Apr 2019 10:41:20 +0200 Thomas Gleixner wrote: > @@ -412,23 +404,20 @@ stack_trace_sysctl(struct ctl_table *tab > void __user *buffer, size_t *lenp, > loff_t *ppos) > { > - int ret; > + int ret, was_enabled; One small nit. Could this be: int was_enabled; int ret; I prefer only joining variables that are related on the same line. Makes it look cleaner IMO. > > mutex_lock(&stack_sysctl_mutex); > + was_enabled = !!stack_tracer_enabled; > Bah, not sure why I didn't do it this way to begin with. I think I copied something else that couldn't do it this way for some reason and didn't put any brain power behind the copy. :-/ But that was back in 2008 so I blame it on being "young and stupid" ;-) Other then the above nit and removing the unneeded +1 in max_entries: Reviewed-by: Steven Rostedt (VMware) -- Steve > ret = proc_dointvec(table, write, buffer, lenp, ppos); > > - if (ret || !write || > - (last_stack_tracer_enabled == !!stack_tracer_enabled)) > + if (ret || !write || (was_enabled == !!stack_tracer_enabled)) > goto out; > > - last_stack_tracer_enabled = !!stack_tracer_enabled; > - > if (stack_tracer_enabled) > register_ftrace_function(&trace_ops); > else > unregister_ftrace_function(&trace_ops); > - > out: > mutex_unlock(&stack_sysctl_mutex); > return ret; > @@ -444,7 +433,6 @@ static __init int enable_stacktrace(char > strncpy(stack_trace_filter_buf, str + len, COMMAND_LINE_SIZE); > > stack_tracer_enabled = 1; > - last_stack_tracer_enabled = 1; > return 1; > } > __setup("stacktrace", enable_stacktrace); >