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 041EBC2D0CD for ; Tue, 17 Dec 2019 15:13:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CFB2221D7D for ; Tue, 17 Dec 2019 15:13:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576595627; bh=0KCyjAy/9GjrsG4kczDuTO3NO1JJuxbaNBl7wrY7rgs=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=EGfNnNmO8rpK8MaxYlEq39l0Ys+GGLmlWYoXnTyhgbyBHkuK6maBlmeeqLCgEhN6W zsCYgadi0LmkFQQv0B9UdEGkFoDZXcn6T5KoQ8egvIVlJXp4z2EqSs3PJtFh3inVan 4+MP0+m4oP4TJ6YABF22DujEu/8WOW6Qod7b/ELQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727797AbfLQPNr (ORCPT ); Tue, 17 Dec 2019 10:13:47 -0500 Received: from mail-wr1-f68.google.com ([209.85.221.68]:39717 "EHLO mail-wr1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727039AbfLQPNq (ORCPT ); Tue, 17 Dec 2019 10:13:46 -0500 Received: by mail-wr1-f68.google.com with SMTP id y11so11693400wrt.6; Tue, 17 Dec 2019 07:13:45 -0800 (PST) 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=84OmudL4nhIn2JLQldH7TGRNUYk7SaIOMOPh/ydmyqE=; b=N7/q4kXHxNb3rYfWavCVzL7GWMzcpe/lf2TZcsM2U1wclANiPA89u3UKo+4zIJEe3s CDWczYcTBYknSNEx/Agm6ClOzAlU/moArhrSFzw+Y4cGav8Ry0CnD5r5lzqzCB97puvv iJhW7eUUOGZEI1fNDkQqtZkf4CR+bhfBx6MMdQ/utV5UXrjsjSriUVoAksjy9+6SOM3/ +thujnVd+IFdNtCLRersTo0HIe9YS4VAyWQgBYJGzwlAejA/MMG7XSZN0wW6s0GGecby 1f76TkSN5OUmLQJxAlZEDbd4X194kiBUfgebAgjx8ltN4OQyBjQhMFd7M49X7RHzw4JR 2dRA== X-Gm-Message-State: APjAAAUFgXYbb82Rs2FepsVp4lWN+UfXiI+7L01qRtYSuwxjrYNl+YHw BWABR4RdNbgWAwioiVgiN7g= X-Google-Smtp-Source: APXvYqzYOMD988kB9mj2RJ66ZpnhbcIyk49ncZyddyoGTYF4n7dVI9PulNh2YOx59yoPntdxj7tJqw== X-Received: by 2002:a5d:4602:: with SMTP id t2mr36952652wrq.37.1576595624656; Tue, 17 Dec 2019 07:13:44 -0800 (PST) Received: from localhost (prg-ext-pat.suse.com. [213.151.95.130]) by smtp.gmail.com with ESMTPSA id g21sm27457018wrb.48.2019.12.17.07.13.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 17 Dec 2019 07:13:43 -0800 (PST) Date: Tue, 17 Dec 2019 16:13:43 +0100 From: Michal Hocko To: Qian Cai Cc: Chris Down , Kuninori Morimoto , Johannes Weiner , Vladimir Davydov , Andrew Morton , cgroups@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] mm: memcontrol.c: move mem_cgroup_id_get_many under CONFIG_MMU Message-ID: <20191217151343.GC7272@dhcp22.suse.cz> References: <20191217144652.GA7272@dhcp22.suse.cz> <43881F9C-90D0-4DE0-BA1E-B74ACF8567BD@lca.pw> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <43881F9C-90D0-4DE0-BA1E-B74ACF8567BD@lca.pw> User-Agent: Mutt/1.12.2 (2019-09-21) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue 17-12-19 10:04:36, Qian Cai wrote: > > > > On Dec 17, 2019, at 9:46 AM, Michal Hocko wrote: > > > > yes, I would just ignore this warning. Btw. it seems that this is > > enabled by default for -Wall. Is this useful for kernel builds at > > all? Does it realistically help discovering real issues? If not then > > can we simply blacklist it? > > -Wunused-function is useful in-general as it caught many dead code > that some commits left unintentionally with real-world configs. I do understand the general purpose of the warning. I am simply not sure the kernel tree is a good candidate with a huge number of different config combinations that might easily result in warnings which would tend to result in even more ifdeferry than we have. -- Michal Hocko SUSE Labs