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=-9.9 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1,USER_IN_DEF_DKIM_WL 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 BDE52C3F2CD for ; Tue, 3 Mar 2020 06:34:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 832E620CC7 for ; Tue, 3 Mar 2020 06:34:05 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="RT+Kea4i" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725765AbgCCGeE (ORCPT ); Tue, 3 Mar 2020 01:34:04 -0500 Received: from mail-ot1-f42.google.com ([209.85.210.42]:34332 "EHLO mail-ot1-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725440AbgCCGeE (ORCPT ); Tue, 3 Mar 2020 01:34:04 -0500 Received: by mail-ot1-f42.google.com with SMTP id j16so1957864otl.1 for ; Mon, 02 Mar 2020 22:34:03 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:from:to:cc:subject:in-reply-to:message-id:references :user-agent:mime-version; bh=nd/TEeW4LQOvJMaEt1rZVabT2kTJB3dRDcejupbt5xY=; b=RT+Kea4iOHlH9H/H9pNH1Sk5JZ4dns1gAbgYhpwbXqqZbzVX5jEh1et1qoLilG5wVs oO2JK/0A0BWeTpwrk38qIZ6XZ4P3iBdLicT+oqLeMT/lp5vTN+FuRTu9OOkmhkC8cJca VNnFYWcAPZnYcrYLsnEGl2OTcQKWgZgulNDfrJbAPifq7V9ST4c9TsnqL5L3xl31itA7 zTqGIMx5oodNwYKcTa39nYsVUZd9viLRjg7pyd6NoVpKZ1KakGNLr2ZMf2jo0YkKKo7G qZSY6uQZE16aoTg0ZtnBdaWfz1YWULza/Pk+PtsfaW25hJEnjirgGc/h7Hl4hMWxRARM 8K9Q== 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:in-reply-to:message-id :references:user-agent:mime-version; bh=nd/TEeW4LQOvJMaEt1rZVabT2kTJB3dRDcejupbt5xY=; b=GhtzSdv/l6wpyQ1JB7hFmpMk4tMwrYWrkwXSUGhuPWhjHlYYtlj0x3WdI/kA0aOryG aA1QpD0cii689gqYmBKRFMImfSzU9w7PcQvf9pRU8k33JmSeTG/Ob2lT612tNGwIO5dV Gbst70HxkdJe4eUL8AnPeMhjFxzn1xcbQKvHQtcB4Da29KFHa0TLVOye21SyhEm8Q9Tm 7/WPWYe7TGDo47QmjUAWgqhRx5wlDZaJGI5DZfMzDhNgved5FAoSf18U54V8h6+sbGcU Hl2oyvmieH9QN6+yD2wq8e2nmBMreHIgM5R5qTVZNxTfAfDLJSy2Oq0/k/Ijl81eZlNs Y1RQ== X-Gm-Message-State: ANhLgQ0e3zXYR2OVg8CHdaS15Iyay5YZ2H1Mm9Z7TbL7pTYZOaG/6rTg 9W0khxRIVHmQvg/OOvKkpu9syQ== X-Google-Smtp-Source: ADFU+vt+oiBRDRmtU/BlPEpanrfpTiCQDOW8t3tex0y3+5iv9DRGttD0LyFJlWuDDjetCc5tLiQDxw== X-Received: by 2002:a05:6830:1203:: with SMTP id r3mr2352162otp.230.1583217243235; Mon, 02 Mar 2020 22:34:03 -0800 (PST) Received: from eggly.attlocal.net (172-10-233-147.lightspeed.sntcca.sbcglobal.net. [172.10.233.147]) by smtp.gmail.com with ESMTPSA id z10sm7243729oih.1.2020.03.02.22.34.01 (version=TLS1 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Mon, 02 Mar 2020 22:34:02 -0800 (PST) Date: Mon, 2 Mar 2020 22:34:00 -0800 (PST) From: Hugh Dickins X-X-Sender: hugh@eggly.anvils To: Anshuman Khandual cc: linux-mm@kvack.org, "David S. Miller" , Alexey Dobriyan , Andrew Morton , Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , Hugh Dickins , sparclinux@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: Re: [RFC 3/3] mm/vma: Introduce some more VMA flag wrappers In-Reply-To: <1583131666-15531-4-git-send-email-anshuman.khandual@arm.com> Message-ID: References: <1583131666-15531-1-git-send-email-anshuman.khandual@arm.com> <1583131666-15531-4-git-send-email-anshuman.khandual@arm.com> User-Agent: Alpine 2.11 (LSU 23 2013-08-11) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Mon, 2 Mar 2020, Anshuman Khandual wrote: > This adds the following new VMA flag wrappers which will replace current > open encodings across various places. This should not have any functional > implications. > > vma_is_dontdump() > vma_is_noreserve() > vma_is_special() > vma_is_locked() > vma_is_mergeable() > vma_is_softdirty() > vma_is_thp() > vma_is_nothp() Why?? Please don't. I am not at all keen on your 1/3 and 2/3 (some of us actually like to see what the VM_ flags are where they're used, without having to chase through scattered wrappers hiding them), but this 3/3 particularly upset me. There is a good reason for the (hideously named) is_vm_hugetlb_page(vma): to save "#ifdef CONFIG_HUGETLB_PAGE"s all over (though I suspect the same could have been achieved much more nicely by #define VM_HUGETLB 0); but hiding all flags in vma_is_whatever()s is counter-productive churn. Improved readability? Not to my eyes. Hugh