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=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham 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 4E423C282D7 for ; Wed, 30 Jan 2019 16:26:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1C7952184D for ; Wed, 30 Jan 2019 16:26:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="nldxZ75+" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731555AbfA3Q0o (ORCPT ); Wed, 30 Jan 2019 11:26:44 -0500 Received: from mail-lj1-f193.google.com ([209.85.208.193]:35050 "EHLO mail-lj1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727371AbfA3Q0o (ORCPT ); Wed, 30 Jan 2019 11:26:44 -0500 Received: by mail-lj1-f193.google.com with SMTP id x85-v6so122971ljb.2 for ; Wed, 30 Jan 2019 08:26:43 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=3SVNRQz+X4Hk9bSAF5GyFdZKD0z7Vt5Oq5UNt9Q9q6Q=; b=nldxZ75+1lLZYS1pcbAgSQ18WXPSb7H9T4+DSVwhkjeYNDaRZ+3cd/fzHKh7q0hp1v kVZwh5M50p4Lpqd88YRvIfWL5QH05Y8z2/Cb/KpU44L/x324pnQ1ycEhVXa7GbJLMVit 0WDPvGw9gQIgEfjP8Bo/qQgb9fMCzqF+vfRdetA5nMkblr4N1y0h/ATSrcYzFMiN9UMm iy4FKBdJnJ9nT3dqz+CQ0LzFgQ0hWVvmuM8eTCLj5m7xg8RO2ANjpBAqDMbfb0dYGFX3 AHkNcyBWC4R+xgSKn5XSSJ/KoiPhi6vjLGpgo5MKomDp9Q+epyi8DpMT52lOLqFfn3P+ m6lg== 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=3SVNRQz+X4Hk9bSAF5GyFdZKD0z7Vt5Oq5UNt9Q9q6Q=; b=D53bwkw8TD8vSOur7lJVPsn8Izul+KxV5sVAviTYwxvDCYLOdmHHUjmkcyosYJnCP6 dtwPN1KlKYrjjW7w8rL7Fz/Zwf8Je3001STMwjYR9Y3XNsvQqlvTBP5hsfbKmgCiG0Zh 3h+zAgDfTFQo0jBuw9jtXrMQIMX3bOuvZnRhe/0mdxwzeek5eRA2qpyn7HWyJyBOGvW5 R68pRAWpa9NzOgGN27bUaazkEzSV/3F9P6lgZMBrtEc0ZpjG/qjbjETRMFDbc+vfvDUm Ly/yl7Qc25So7ODumrfbMjEgsK5UPoBzfpZR7pW+LAmstEuG7Q91WdDMUN7Zekx5jx16 REyQ== X-Gm-Message-State: AJcUukf4BkJc181SsgBWsQZqeDaOnLsQ2yrZEPv+zR1DbEP/xi04lvnG 7onr/2E0/WxjoD/K2AKjTpvuElXj X-Google-Smtp-Source: ALg8bN4pRQjnb36ixk+6o86Pzm/aqRRsQ6PYtW7uDc9JBrul8QnYPDEnDyccaTvUues47rdDduvTmw== X-Received: by 2002:a2e:9cd5:: with SMTP id g21-v6mr24742223ljj.48.1548865601896; Wed, 30 Jan 2019 08:26:41 -0800 (PST) Received: from uranus.localdomain ([5.18.103.226]) by smtp.gmail.com with ESMTPSA id 11-v6sm345985ljv.1.2019.01.30.08.26.41 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 30 Jan 2019 08:26:41 -0800 (PST) Received: by uranus.localdomain (Postfix, from userid 1000) id DFA9E46077D; Wed, 30 Jan 2019 19:26:39 +0300 (MSK) Date: Wed, 30 Jan 2019 19:26:39 +0300 From: Cyrill Gorcunov To: Al Viro Cc: LKML Subject: Re: [PATCH next] fs/splice: iter_to_pipe -- Use PIPE_DEF_BUFFERS instead of hardcoded number Message-ID: <20190130162639.GA25251@uranus> References: <20190130153911.GJ2332@uranus.lan> <20190130154245.GK2217@ZenIV.linux.org.uk> <20190130154851.GK2332@uranus.lan> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190130154851.GK2332@uranus.lan> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jan 30, 2019 at 06:48:51PM +0300, Cyrill Gorcunov wrote: > On Wed, Jan 30, 2019 at 03:42:45PM +0000, Al Viro wrote: > > On Wed, Jan 30, 2019 at 06:39:11PM +0300, Cyrill Gorcunov wrote: > > > And use ARRAY_SIZE for easier code modification if we ever need in future. > > > > Umm... Why PIPE_DEF_BUFFERS, though? Because it's a constant from more or > > less the same area that happens to be equal to the value we use here? > > Yes. Since plain 16 value completely unclear where it comes from. I looked > into your commit which made this change and seems previously we've had this > constant related (79fddc4efd5d4de5cf210fe5ecf4d2734140849a). Am I wrong? Thinking more I'm more convinced that i'm wrong. Also it is related to this default size, the code can pretty well use (alsmost) any other constant here. Al, drop it please.