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=-1.1 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 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 C4DC8C43387 for ; Fri, 11 Jan 2019 16:12:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 946C220700 for ; Fri, 11 Jan 2019 16:12:10 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="tIGcLPO3" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387593AbfAKQMJ (ORCPT ); Fri, 11 Jan 2019 11:12:09 -0500 Received: from mail-it1-f196.google.com ([209.85.166.196]:55736 "EHLO mail-it1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728944AbfAKQMI (ORCPT ); Fri, 11 Jan 2019 11:12:08 -0500 Received: by mail-it1-f196.google.com with SMTP id m62so3260360ith.5; Fri, 11 Jan 2019 08:12:08 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=nlBzsEs/XxBusvnYWKzL1PBITBpfByToXfynZ72hRww=; b=tIGcLPO3tNyxvASaaMmclrPxueuO9Mqp4FzY0bFDxrFLDXXzWkBmGF0NIBAxahwWAh zdfW6NBbj3Xu5n90AtMVUb8slD1unzPb3TZiSXkcI/QBIY4G98wf0RjreGB3ebb0y7sE C9BPS1KBEpi+JFK+WsUCCW/+41k6fRUU/TkvjY5qN/OQJJCqNwO19T9ndD/NfxT/6/49 lLz3cteMGH9s9Sx6G8hkj9CACYJPkfG1b0gGpkBW4uNqGXv4Oz7NhbUdxYPVRMJ0ID3x bSzA2NBbSPQhoihuQZd58lMLy789oDYkq8n0eJyQnsgJZnxA4tXpRBWU4F58AcpQPw3f oh1g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=nlBzsEs/XxBusvnYWKzL1PBITBpfByToXfynZ72hRww=; b=RKOzDtDLPFaBh5xgiIeh+fsOMxdsMEYIHY9N00zv4LDxf9vnxY/kANaCCMPK+O9vVn IAZzRTWv9yT1w+/AJe/FbPGY5bQZhiym1mj59ngyiiDAhLAETb9em24VDAy5zF96BbHc cuyzbT0BRTrkLndqB3KbFGZti5kpANVBePNPohRONVrIF05Vg/U8DRbnBH3bZUL7oZW8 6AWKHO39bWRWVPCf5JM3/P+Asgwt+ETLGyvtM9ot/gTio+gOBZl2hsnseWCgHP7xOLmJ lJOqCz+NXPJGOhs20lrj1Ff9oM1KtIxS85TfyykrEKRP8dj+d0T1cEOK8ROu577edqy/ 4pMQ== X-Gm-Message-State: AJcUukddQAA8s/44aGhOMeWpTdVlYXZ6YSyfVJ+YvgIFlzPHfdf7WDze FvOYaL1CeBZ3I5xc6MyX5VVS4CnvGTdsLBPgF8s= X-Google-Smtp-Source: ALg8bN6KyNJEZkJomzRQWBOwyrZfdzQYREHKE/HOgkQBqA7CXQdqBzty3YXh6x4hwKucnEFX7vr3tjEXKBUDalkJkY0= X-Received: by 2002:a24:d3cb:: with SMTP id n194mr1530248itg.57.1547223128088; Fri, 11 Jan 2019 08:12:08 -0800 (PST) MIME-Version: 1.0 References: <20190110024404.25372-1-axboe@kernel.dk> In-Reply-To: From: Ilya Dryomov Date: Fri, 11 Jan 2019 17:11:57 +0100 Message-ID: Subject: Re: [PATCHSET v2] io_uring IO interface To: Roman Penyaev Cc: Jens Axboe , linux-fsdevel , linux-aio@kvack.org, linux-block , linux-arch@vger.kernel.org, Christoph Hellwig , jmoyer@redhat.com, avi@scylladb.com, linux-block-owner@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Fri, Jan 11, 2019 at 10:51 AM Roman Penyaev wrote: > > Hi Jens, > > That is interesting. Recently I sent an rfc related to epoll uring: > > https://lore.kernel.org/lkml/20190109164025.24554-1-rpenyaev@suse.de > > which can be mapped to userspace and all ready events can be consumed > from it directly. I am wondering, is it possible to make some common > API for all kind of ready events / urings, or it doesn't make any > sense? I think you can use the new IOCB_CMD_POLL from Christoph and avoid epoll_wait() in favor of aio/io_uring interface, at least in new high performance applications. Reaping events entirely in userspace (i.e. performing io_getevents() without entering the kernel) has been possible for a long time even with the existing aio interface. Thanks, Ilya