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=-0.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 6DAF0C433E0 for ; Sun, 5 Jul 2020 03:27:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3D25B2082F for ; Sun, 5 Jul 2020 03:27:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="iBIPzR9S" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728196AbgGED1f (ORCPT ); Sat, 4 Jul 2020 23:27:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44562 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728134AbgGED1f (ORCPT ); Sat, 4 Jul 2020 23:27:35 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 50729C061794; Sat, 4 Jul 2020 20:27:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=1HVM69sv+KPc2VykHuUhGFUMm1maJllg1rLH5d0wrGI=; b=iBIPzR9Sa0ULgSA8+esCMwsd4Y 34wYp+leVZuoUSA7vDu0P2uNvfw02uVtOcf4nBvO/9DGJ4cvnnAdjs9f8Q243z9pH591p+qVeBzTw OntSKXqGDTKDTMg050aSyqR7o6RybIgcGbOo5bmHiAAA1qyHsSlejlBcZAuTWkNknc+LL2eypr6BB S2KihTLxJ3Hf3Qll95PiUlzjSe5MoJSQzfaAkJq+11eZ+45Me+mDTAytoC270fcm0FPFtPc+1V9hZ fnbj6frNwxIgvNxr+IeFADhaWQLfP92jHGerXeucZlJNH+n7Q8MM91XEPc4aTEkyFvXWLkzAAzVw3 2w3fH2YA==; Received: from willy by casper.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1jrvJU-0002Rw-JD; Sun, 05 Jul 2020 03:27:32 +0000 Date: Sun, 5 Jul 2020 04:27:32 +0100 From: Matthew Wilcox To: Jan Ziak <0xe2.0x9a.0x9b@gmail.com> Cc: gregkh@linuxfoundation.org, linux-api@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-man@vger.kernel.org, mtk.manpages@gmail.com, shuah@kernel.org, viro@zeniv.linux.org.uk Subject: Re: [PATCH 0/3] readfile(2): a new syscall to make open/read/close faster Message-ID: <20200705032732.GT25523@casper.infradead.org> References: <20200705021631.GR25523@casper.infradead.org> <20200705031208.GS25523@casper.infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: linux-api-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-api@vger.kernel.org On Sun, Jul 05, 2020 at 05:18:58AM +0200, Jan Ziak wrote: > On Sun, Jul 5, 2020 at 5:12 AM Matthew Wilcox wrote: > > > > You should probably take a look at io_uring. That has the level of > > complexity of this proposal and supports open/read/close along with many > > other opcodes. > > Then glibc can implement readfile using io_uring and there is no need > for a new single-file readfile syscall. It could, sure. But there's also a value in having a simple interface to accomplish a simple task. Your proposed API added a very complex interface to satisfy needs that clearly aren't part of the problem space that Greg is looking to address.