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=-2.5 required=3.0 tests=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 2933DC43603 for ; Tue, 17 Dec 2019 15:13:47 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id E96152146E for ; Tue, 17 Dec 2019 15:13:46 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E96152146E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 95D348E0082; Tue, 17 Dec 2019 10:13:46 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 90DF08E0079; Tue, 17 Dec 2019 10:13:46 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 7FC648E0082; Tue, 17 Dec 2019 10:13:46 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0150.hostedemail.com [216.40.44.150]) by kanga.kvack.org (Postfix) with ESMTP id 6B5A18E0079 for ; Tue, 17 Dec 2019 10:13:46 -0500 (EST) Received: from smtpin05.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with SMTP id 1D4868249980 for ; Tue, 17 Dec 2019 15:13:46 +0000 (UTC) X-FDA: 76274978052.05.ants83_5b0cbdef43818 X-HE-Tag: ants83_5b0cbdef43818 X-Filterd-Recvd-Size: 3347 Received: from mail-wr1-f68.google.com (mail-wr1-f68.google.com [209.85.221.68]) by imf48.hostedemail.com (Postfix) with ESMTP for ; Tue, 17 Dec 2019 15:13:45 +0000 (UTC) Received: by mail-wr1-f68.google.com with SMTP id t2so11733857wrr.1 for ; 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=ShijsEBN6bpxHSC3lg74CYFtLDQQrUO5Ap7V7waRwcl/o/C58WSpAEXn09+8cvCpDX J0mJQrfxbM/FXvLcpeA9Hf2m82TfpJHIyYqv/L3wAV7PylgFeGSqcG2oBltgX19npxe6 VRxVRJdsPQXSpNRKHnDqXh+lD9yux2lrh3eCwdPER7Up8U7dBviwRrEb+QHmRgUnZ/I1 8heWhUcScV8zLIOM7/joX6xh4GOiv8setSWSn8tSwVoPI440TS6O0vz71xfho9PAxcXq mtLiGvaLEOAnEeYF84vo7/ft8w+cK5hfuI8dz7C19kK4DbYpA8d1OQRMxFcM0NaZz4/+ Y0kA== X-Gm-Message-State: APjAAAXjaVAitUvZQhD9gztShyqR8rKpGhRg4HJXiWab6sRkVQNheg52 6670narjaHqsecNdoG8+edYxqoAB 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) X-Bogosity: Ham, tests=bogofilter, spamicity=0.000010, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: 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