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=-0.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 ECFC1C433DF for ; Fri, 29 May 2020 15:02:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C6CC520776 for ; Fri, 29 May 2020 15:02:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="CFm+RbtG" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726903AbgE2PCf (ORCPT ); Fri, 29 May 2020 11:02:35 -0400 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:37201 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726476AbgE2PCf (ORCPT ); Fri, 29 May 2020 11:02:35 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1590764553; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=lV3Lg1mm8lwM4+kuioEU6LnhzDq9n3BD9WBg/44Moz4=; b=CFm+RbtGVQIUpgtRuIG03jdqzDbpiY+X8A3QuSSnx7jxBqvDYDEx5in/S1+A8fDVnWm7i9 KJ3gsMOrSb4f425pjGGwKH4OvddyZ6P0kek+6lvFyj3ekbTfm7Hyyf38WQj74Fc6dnZq/x X9TUA8ITyUF9qZd5C7PFpnAR7nR4ZFA= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-144-kgy6AAhYMhG-7dtZ0LlZww-1; Fri, 29 May 2020 11:02:31 -0400 X-MC-Unique: kgy6AAhYMhG-7dtZ0LlZww-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id BC2E08017CC; Fri, 29 May 2020 15:02:30 +0000 (UTC) Received: from segfault.boston.devel.redhat.com (segfault.boston.devel.redhat.com [10.19.60.26]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 631225D9D5; Fri, 29 May 2020 15:02:30 +0000 (UTC) From: Jeff Moyer To: Jens Axboe Cc: Bijan Mottahedeh , io-uring@vger.kernel.org Subject: Re: [RFC 2/2] io_uring: mark REQ_NOWAIT for a non-mq queue as unspported References: <1589925170-48687-1-git-send-email-bijan.mottahedeh@oracle.com> <1589925170-48687-3-git-send-email-bijan.mottahedeh@oracle.com> <0ab35b4b-be67-8977-08ea-2998a4ac1a7e@kernel.dk> <798e24c7-b973-00c7-037f-4095e43515b7@kernel.dk> <6ca210e3-eba6-0621-3ebc-d3545f5ad7e9@kernel.dk> X-PGP-KeyID: 1F78E1B4 X-PGP-CertKey: F6FE 280D 8293 F72C 65FD 5A58 1FF8 A7CA 1F78 E1B4 Date: Fri, 29 May 2020 11:02:29 -0400 In-Reply-To: <6ca210e3-eba6-0621-3ebc-d3545f5ad7e9@kernel.dk> (Jens Axboe's message of "Thu, 28 May 2020 17:03:39 -0600") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Sender: io-uring-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org Jens Axboe writes: > On 5/28/20 4:12 PM, Jeff Moyer wrote: >> Jens Axboe writes: >> >>>> poll won't work over dm, so that looks correct. What happens if you edit >>>> it and disable poll? Would be curious to see both buffered = 0 and >>>> buffered = 1 runs with that. >>>> >>>> I'll try this here too. >>> >>> I checked, and with the offending commit reverted, it behaves exactly >>> like it should - io_uring doesn't hit endless retries, and we still >>> return -EAGAIN to userspace for preadv2(..., RFW_NOWAIT) if not supported. >>> I've queued up the revert. >> >> With that revert, I now see an issue with an xfs file system on top of >> an nvme device when running the liburing test suite: >> >> Running test 500f9fbadef8-test >> Test 500f9fbadef8-test failed with ret 130 >> >> That means the test harness timed out, so we never received a >> completion. > > I can't reproduce this. Can you try again, and enable io_uring tracing? > > # echo 1 > /sys/kernel/debug/tracing/events/io_uring/enable > > run test > > send the 'trace' file, or take a look and see what is going on. I took a look, and it appeared as though the issue was not in the kernel. My liburing was not uptodate, and after grabbing the latest, the test runs to completion. Thanks! Jeff