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=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_MUTT 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 95C86C282E3 for ; Thu, 23 May 2019 14:53:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 694DC20863 for ; Thu, 23 May 2019 14:53:21 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=amarulasolutions.com header.i=@amarulasolutions.com header.b="Sl9c/IVp" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730992AbfEWOxU (ORCPT ); Thu, 23 May 2019 10:53:20 -0400 Received: from mail-wr1-f65.google.com ([209.85.221.65]:36454 "EHLO mail-wr1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730957AbfEWOxS (ORCPT ); Thu, 23 May 2019 10:53:18 -0400 Received: by mail-wr1-f65.google.com with SMTP id s17so6646601wru.3 for ; Thu, 23 May 2019 07:53:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amarulasolutions.com; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=KuauVzjJswarfobGLMx62HbVwFkgBXXbK672bwB029A=; b=Sl9c/IVpkPxfdQFvyhEaxuRn1gyGyncWJpElpyHVCz0PT2Jqa0CZ78ux8e4bvp/UDK 9VGVElVF1dfjJUkX9iP/zAXDhTRf5rhu5AkZfZwIPthOEGQLaemCwa7mO+bs7KhepM9W b/Q1OdXSLuvvNGxjKUhlYBAIKZPFsLK2aloT4= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=KuauVzjJswarfobGLMx62HbVwFkgBXXbK672bwB029A=; b=jwaG/mpmt2Jhdj8gKtCTBbR2nPFvG+DyQj1d5uTryGwUY78tGI99EFoN61H1FFCWJz Zg02MYSXvnOshojAlAOalDr7J4gCtOVRUs/i40Ng2BzTXbSc9Z7umeNrXKgFmqZWgI0v AS1K/uh312iuVu4utf4h1QznixZjmiYnHA6vxDvkT1I+S0giNNPFAMlZ33smAXyyd6xl MoquwzjTKknMHgNkRjbLmVu6BielZvcNWHP8LPQhA7wCV7XRPx2OwM8kzo0rUfLx32FU ELyZ4co70J/xed8UGbAEEJKqjPi79GcdPgpfridwEc4XQfY3ZHqQclB0RukqTbr5JVwv TXpw== X-Gm-Message-State: APjAAAUQnHhDbvNX9SklJxY6rVH739xlZIClmorU1kbqhMbUvDuZFKs/ lHdoho7yc3vOlkQqmU7BIqlxSw== X-Google-Smtp-Source: APXvYqzoZglxEGBUuaQVwNP9WVW+5YjppemivpSRz1xRQFi3El+oY+7xYQL+IEIzgLJn+DvEfnJcCA== X-Received: by 2002:adf:aa09:: with SMTP id p9mr6578948wrd.59.1558623197442; Thu, 23 May 2019 07:53:17 -0700 (PDT) Received: from andrea (86.100.broadband17.iol.cz. [109.80.100.86]) by smtp.gmail.com with ESMTPSA id j206sm14293686wma.47.2019.05.23.07.53.16 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 23 May 2019 07:53:16 -0700 (PDT) Date: Thu, 23 May 2019 16:53:09 +0200 From: Andrea Parri To: "Paul E. McKenney" Cc: linux-kernel@vger.kernel.org, Josh Triplett , Steven Rostedt , Mathieu Desnoyers , Lai Jiangshan , Joel Fernandes , rcu@vger.kernel.org, Peter Zijlstra , Will Deacon , Mark Rutland Subject: Re: [RFC PATCH] rcu: Make 'rcu_assign_pointer(p, v)' of type 'typeof(p)' Message-ID: <20190523145309.GA18692@andrea> References: <1558618340-17254-1-git-send-email-andrea.parri@amarulasolutions.com> <20190523135013.GL28207@linux.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190523135013.GL28207@linux.ibm.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > > TBH, I'm not sure this is 'the right patch' (hence the RFC...): in > > fact, I'm currently missing the motivations for allowing assignments > > such as the "r0 = ..." assignment above in generic code. (BTW, it's > > not currently possible to use such assignments in litmus tests...) > > Given that a quick (and perhaps error-prone) search of the uses of > rcu_assign_pointer() in v5.1 didn't find a single use of the return > value, let's please instead change the documentation and implementation > to eliminate the return value. Thanks for the confirmation, Paul; I'll prepare the new patch shortly... Andrea