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=-8.6 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,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 4FB43C433E1 for ; Sun, 16 Aug 2020 21:09:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 21B0A20855 for ; Sun, 16 Aug 2020 21:09:27 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="kRxLBh/9" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726904AbgHPVJZ (ORCPT ); Sun, 16 Aug 2020 17:09:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33544 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726425AbgHPVJZ (ORCPT ); Sun, 16 Aug 2020 17:09:25 -0400 Received: from mail-qt1-x844.google.com (mail-qt1-x844.google.com [IPv6:2607:f8b0:4864:20::844]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B3E39C061786 for ; Sun, 16 Aug 2020 14:09:24 -0700 (PDT) Received: by mail-qt1-x844.google.com with SMTP id s16so11018163qtn.7 for ; Sun, 16 Aug 2020 14:09:24 -0700 (PDT) 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:content-transfer-encoding; bh=yhjJ0pMrwVO2qLTg3OG+WTyBApmohHyaQYDPam7BPrk=; b=kRxLBh/9LY5UeIt8070CUXHQPHx8cMUROcSXJcGm9hmdsCrpOlXHfLxFNqm764DOrH ZYmHf3A8mgKr7aXmp66xQjmQk2CjB8vg0jUUunTIkGhyA7o9CkELZbeGNRyoe/5HAFcz 9ZNchnXR4Fhzoq7YT960uueQhkfBfX3cpcMx6FeuYeEj21AUhPUvp1S/DdRhlbyfeqON mCtRMSU8De51YlQO9We3rOtP1aXjLZOj56SOwIW+43Hwt+IiUxGEOFDjOWdBTdtWdfjx RFzrug/g+kv/d8L6XvPNAyr+P9UNa959xwHNYPAWinGRdPPy6XH1FfY0ykprelvUQKs1 dhpw== 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:content-transfer-encoding; bh=yhjJ0pMrwVO2qLTg3OG+WTyBApmohHyaQYDPam7BPrk=; b=Bz5NmAPZm/WLg9h+uiN5Qbf5wksGyaqb53io9X+rae/8ILBvEMMugs1omC1X7uUXiS /ZmXECCe4kF8PABlPAxkjMHw6jlRUKw4DqN2YKtpIrBpLVPpKEyMp8Dg1CSJP7HlsknT 30PPQ61d1T1aOdeB+79d+W7OTfC7t0FvQxc/mFT+EHKBKPGWxz+P38SvKiMH1urNRtSJ H6AZQjmFquCSn2MfgxN2QQ0XE7ovaKUfj3fHYdDvbfo1nFP5ImUC2xKg2XsUxJ7yYhFB FoDR0v2u7MOIPaR0BNy9/HunkHz8D0cPk9sP0RuQDzUV8LE7GFlDeWA2MbiF8CBbU0WL KAtg== X-Gm-Message-State: AOAM532qnk9S2M6oOEYnwEDGX8q2dLOgbrMezOca7JUrNXkcxAGfYzeM xYtcpshmDTPISiWpevYmYi+B711dcvLH6Y6sq2xqLQL5UQ9obFsd X-Google-Smtp-Source: ABdhPJz0adx3LOkrCJby2B/a6fXUrmDUfTUpQGRx3hdkYuW02P+iNOh4cfh1timH07Kj7GLrjSEL7Ch84JnIgInoyaA= X-Received: by 2002:ac8:70cd:: with SMTP id g13mr10985582qtp.53.1597612161802; Sun, 16 Aug 2020 14:09:21 -0700 (PDT) MIME-Version: 1.0 References: <8e734ada-7f28-22df-5f30-027aca3695d1@gmail.com> <5fa9e01f-137d-b0f8-211a-975c7ed56419@gmail.com> <63024e23-2b71-937a-6759-17916743c16c@gmail.com> <904b4d74-09ec-0bd3-030a-59b09fb1a7da@kernel.dk> <390e6d95-040b-404e-58c4-d633d6d0041d@kernel.dk> <63b47134-ad9c-4305-3a19-8c5deb7da686@kernel.dk> <689aa6e9-bfff-3353-fc09-d8dec49485bd@kernel.dk> In-Reply-To: From: Josef Date: Sun, 16 Aug 2020 23:09:10 +0200 Message-ID: Subject: Re: io_uring process termination/killing is not working To: Jens Axboe , io-uring@vger.kernel.org, Pavel Begunkov Cc: norman@apache.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Sender: io-uring-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org > BTW, something I think you're aware of, but wanted to bring up > explicitly - if IORING_FEAT_FAST_POLL is available in the ring features, > then you generally don't want/need to link potentially blocking requests > on pollable files with a poll in front. io_uring will do this > internally, and save you an sqe and completion event for each of these > types of requests. > > Your test case is a perfect example of that, neither the accept nor the > socket read would need a poll linked in front of them, as they are both > pollable file types and will not trigger use of an async thread to wait > for the event. Instead an internal poll is armed which will trigger the > issue of that request, when the socket is ready. I agree as well I don't need a poll linked in font of read event, but not for the non blocking accept event because of this fix in Linux 5.8: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?= h=3Dv5.8&id=3De697deed834de15d2322d0619d51893022c90ea2 I receive an immediate response to tell if there's ever any data there, same behaviour like accept non blocking socket, that=E2=80=99s why I use poll link to avoid that -- Josef Grieb