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=-2.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,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 C09FAC432C3 for ; Fri, 15 Nov 2019 21:26:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 956EB20733 for ; Fri, 15 Nov 2019 21:26:37 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=kernel-dk.20150623.gappssmtp.com header.i=@kernel-dk.20150623.gappssmtp.com header.b="XUesHK2o" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726890AbfKOV0h (ORCPT ); Fri, 15 Nov 2019 16:26:37 -0500 Received: from mail-io1-f53.google.com ([209.85.166.53]:43104 "EHLO mail-io1-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726598AbfKOV0h (ORCPT ); Fri, 15 Nov 2019 16:26:37 -0500 Received: by mail-io1-f53.google.com with SMTP id r2so6831921iot.10 for ; Fri, 15 Nov 2019 13:26:36 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20150623.gappssmtp.com; s=20150623; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=0xibZ013otwd37avQJB6w6rnfqu5PZISVC58dUyWTbE=; b=XUesHK2oLrShjkrEST268zIX1iSEvCuCDBovKsVuhUjctzKjpnRxIunz2cxl0NZTkz KvhGEXmM9sZCUVBgivmtFpa73kZUvAWM273p+2hadSG4/AzRruU9cTsUHZZxZUeOZlgx jJTeAT5YtKD87xOoe6ED9R5py9XfPLbWVVDqCsTZQTZmQEmvsMLVRwAobYpXcmsf5IqH UKVGOdI2ogCXkiTQ+uTEFH/7DLN2ucOT+ABKSTNKwB8SMr7fwWEC7S2kQyuvyhHS8X5b EwTKoyeRQrlrGZeO5IpDhOXX1SYlaAio8KOYzdZQo3g+fJS93fIp1fcpXrQlQ0RZsLLv 6jaA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=0xibZ013otwd37avQJB6w6rnfqu5PZISVC58dUyWTbE=; b=onn35r0A7s86tffyLY4BP1bwj/pAC6SsG+oBi/8mWhmJ5frB/FxrgtsTxb98xU9DRC kIhivRTq58IVARH/nT15PWLTnSI31IbqobX44zDoxfwe59pULQFxz1hG9XDR3Wajjw8J D4H+i4pspEFaALuOU5EX+NP/UlE6vELu8I5yrJZ40mUW/4nYjcC6Lm8MlD+LhblJPg5l elTHfihR++VfY/ra4Ng1RiZR4iiVCbAiRsb7vY4y521l8VqTHkYQmY4KeWm5F0ZvJAic 8onImtHJkYdwrhuVOqMBUY33iFea5O1haSTQL0WoUCsPZ9cE8XIUn1RMKI1YfAeKHpe1 X8eg== X-Gm-Message-State: APjAAAX5uhpevj0uXQkXVhpJngCwTeQtWK/hOAv3IiBcXN5aqJJ8WlO1 L5vpTV6L3QGwkqiazm5+betZfA== X-Google-Smtp-Source: APXvYqz2Cacn7i7KAkz/AoEXTLnQaChHCkubu6fpzisXWPKzQwgIYMpWH93aLxYNlDS0jy/sEmsBNw== X-Received: by 2002:a05:6602:187:: with SMTP id m7mr2892095ioo.16.1573853196245; Fri, 15 Nov 2019 13:26:36 -0800 (PST) Received: from [192.168.1.159] ([65.144.74.34]) by smtp.gmail.com with ESMTPSA id z24sm1478582ioc.47.2019.11.15.13.26.34 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 15 Nov 2019 13:26:35 -0800 (PST) Subject: Re: [PATCHSET 0/2] io_uring support for linked timeouts To: Pavel Begunkov , io-uring@vger.kernel.org, linux-block@vger.kernel.org Cc: zeba.hrvoje@gmail.com, liuyun01@kylinos.cn References: <20191105211130.6130-1-axboe@kernel.dk> <4566889a-7e12-9bfd-b2a1-716d8b934684@gmail.com> <9b6cd06b-cd6c-d7e5-157b-32c1e2e9ceac@kernel.dk> <3c0ef10d-9524-e2e2-abf2-e1b0bcee9223@gmail.com> <178bae7d-3162-7de2-8bb8-037bac70469b@gmail.com> <2b35c1a0-69bf-1e50-8bda-2fff73bac8de@kernel.dk> <06929659-a545-87c8-fbf4-edfc01c69520@gmail.com> From: Jens Axboe Message-ID: <71860cea-313d-b6ef-895d-9635c73d7530@kernel.dk> Date: Fri, 15 Nov 2019 14:26:33 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.9.0 MIME-Version: 1.0 In-Reply-To: <06929659-a545-87c8-fbf4-edfc01c69520@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: io-uring-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On 11/15/19 2:22 PM, Pavel Begunkov wrote: > On 15/11/2019 22:34, Jens Axboe wrote: >> How about something like this? Should work (and be valid) to have any >> sequence of timeout links, as long as there's something in front of it. >> Commit message has more details. > > If you don't mind, I'll give a try rewriting this. A bit tight > on time, so hopefully by this Sunday. > > In any case, there are enough of edge cases, I need to spend some > time to review and check it. Of course, appreciate more eyes on this for sure. We'll see what happens with 5.4 release, I suspect it won't happen until 11/24. In any case, this is not really staged yet, just sitting in for-5.5/io_uring-post as part of a series that'll likely go in after the initial merge. > REQ1 -> LINKED_TIMEOUT -> REQ2 -> REQ3 > Is this a valid case? Just to check that I got this "can't have both" right. > If no, why so? I think there are a lot of use cases for this. Yes, it's valid. With the recently posted stuff, the only invalid case is having a linked timeout as the first entry since that's nonsensical. It has to be linked from a previous request. We no longer need to restrict where the linked timeout appears otherwise. -- Jens Axboe