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=-2.2 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 BDFCBC35240 for ; Fri, 24 Jan 2020 01:28:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9009221D7E for ; Fri, 24 Jan 2020 01:28:13 +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="gVP6U6Q+" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729837AbgAXB2K (ORCPT ); Thu, 23 Jan 2020 20:28:10 -0500 Received: from mail-pj1-f67.google.com ([209.85.216.67]:53047 "EHLO mail-pj1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729680AbgAXB2J (ORCPT ); Thu, 23 Jan 2020 20:28:09 -0500 Received: by mail-pj1-f67.google.com with SMTP id a6so304965pjh.2 for ; Thu, 23 Jan 2020 17:28:09 -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=3UtLf7+5DucsSWidbQFY9Ttw4iR1dzCtjU7T/DXapxA=; b=gVP6U6Q+p98YXgmlCFAuFYsRrG2LhhCKcAevido9e2FXnwhgzhQaMBNzIcZnbZPgme vMsV9dcOv+/XVfmge9n3XbCfPWsrNNvY5lxoQ37yHSs4zMSn5o3RFqKJV4Ws1eFc7nDC dSd+YFogdIS74Xp1TMCIElLjf0t+sT91d0F478AknsxEjXLtCwxxZ4ti7orpg6BADF/f lgWNOGUtqRRzQUXvRi/TIn08j8fcxszdGDLsfZLJ3S+V44+31NRSHEr98BLSE0B8EWbi cGP+aJzOSus2vIBCEFejX63wsTfcVEmYaKA/7J0ir4nr/jUtj8vOhZ+ephw+aGFdOQ/v dqdA== 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=3UtLf7+5DucsSWidbQFY9Ttw4iR1dzCtjU7T/DXapxA=; b=ShtsGA/ZBzD3I9TFJIREfse73nUXsurSkBFsu7Hd+Yvq3A6Rnx22JyNLVYZ5WAakIw LHOJUT33h1TGcOBmf6ZUrJ8A7oEvpUJB0H4FoItQRga2smBq/giT/GZQlH/yUXxFOS4f uK8VzaemsfXxrqTwlcmKy7984uoLPDdcVloaKENUJ/kjI62U2NQArQFmEn1jej12PSZ/ nK/GoMDZnP2+vwrZ4YlRsCf4OGQ1bxbgqqCOaDj95uBEtAlecFYekf1noY//qBzEwYQW Y6DYIe4xq7vPdRTzPnS89Do9JgIgaclXNvOAGc7Oo5zeXBL/nkgzT4++2DByqxSe1mhk veyA== X-Gm-Message-State: APjAAAVnDJg7DBJxCQsc3S7ujgvZC29qaikeD/7v0lR8PzWFWDJ9Lovp o5qn0oK7Suy8PXsFJKAb9IGZUi1OSio= X-Google-Smtp-Source: APXvYqzx5MP5rjHYQq3kzzvu651bu9Kdur2mhOsrCqElHx/Qa+CIW2Rn8N1iwWP9tMyek247IQy+tQ== X-Received: by 2002:a17:90a:da04:: with SMTP id e4mr571675pjv.26.1579829288529; Thu, 23 Jan 2020 17:28:08 -0800 (PST) Received: from [192.168.201.136] ([50.234.116.4]) by smtp.gmail.com with ESMTPSA id b8sm4091967pff.114.2020.01.23.17.28.07 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 23 Jan 2020 17:28:08 -0800 (PST) Subject: Re: [PATCH] io_uring: wakeup threads waiting for EPOLLOUT events To: Stefano Garzarella Cc: Alexander Viro , io-uring@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org References: <20200116134946.184711-1-sgarzare@redhat.com> <2d2dda92-3c50-ee62-5ffe-0589d4c8fc0d@kernel.dk> <20200116155557.mwjc7vu33xespiag@steredhat> <5723453a-9326-e954-978e-910b8b495b38@kernel.dk> <20200116162630.6r3xc55kdyyq5tvz@steredhat> <20200116170342.4jvkhbbw4x6z3txn@steredhat> <2d3d4932-8894-6969-4006-25141ca1286e@kernel.dk> <20200123214533.ikn4olf7k5dfbaq6@steredhat> From: Jens Axboe Message-ID: <3805d100-c687-e49e-9317-7cd9b387a3a7@kernel.dk> Date: Thu, 23 Jan 2020 18:28:06 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.4.1 MIME-Version: 1.0 In-Reply-To: <20200123214533.ikn4olf7k5dfbaq6@steredhat> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On 1/23/20 2:45 PM, Stefano Garzarella wrote: > On Thu, Jan 23, 2020 at 12:13:57PM -0700, Jens Axboe wrote: >> On 1/16/20 10:03 AM, Stefano Garzarella wrote: >>> On Thu, Jan 16, 2020 at 09:30:12AM -0700, Jens Axboe wrote: >>>> On 1/16/20 9:26 AM, Stefano Garzarella wrote: >>>>>> Since the use case is mostly single submitter, unless you're doing >>>>>> something funky or unusual, you're not going to be needing POLLOUT ever. >>>>> >>>>> The case that I had in mind was with kernel side polling enabled and >>>>> a single submitter that can use epoll() to wait free slots in the SQ >>>>> ring. (I don't have a test, maybe I can write one...) >>>> >>>> Right, I think that's the only use case where it makes sense, because >>>> you have someone else draining the sq side for you. A test case would >>>> indeed be nice, liburing has a good arsenal of test cases and this would >>>> be a good addition! >>> >>> Sure, I'll send a test to liburing for this case! >> >> Gentle ping on the test case :-) >> > > Yes, you are right :-) > > I was a little busy this week to finish some works before DevConf. I > hope to work on the test case these days, so by Monday I hope I have > it ;-) Thanks, all good, just a gentle nudge ;-) -- Jens Axboe