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=-15.1 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 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 977EDC433E0 for ; Wed, 20 Jan 2021 22:26:04 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 1D68A235FF for ; Wed, 20 Jan 2021 22:26:04 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1D68A235FF Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:53148 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1l2LvP-00070I-1H for qemu-devel@archiver.kernel.org; Wed, 20 Jan 2021 17:26:03 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:53058) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1l2Lu5-0005XO-Kz for qemu-devel@nongnu.org; Wed, 20 Jan 2021 17:24:41 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:33271) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1l2Lu3-0002y6-3I for qemu-devel@nongnu.org; Wed, 20 Jan 2021 17:24:41 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1611181478; 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: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=4EhEEVpeJ0k0j4TiWNnFVnusr0hlfuBzBFzC39D51eo=; b=ZQF4XOvxNUCIuUQvlaBvTDUpDddo59DYrZQyZp8gD3iUySyavM8InrH9lj6+QGjtVLXSiw EhhBWGt/89XC5KFZogLsBP4Q69cMXmog+4idS4ONT67+mJ7W3dy7a/HLDdEV9e133UW4pe CkMfgEpGtTiaouhQU+GDEHRFQZ/QRK8= 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-284-xDOzmqpON9-iOtFivxqb4A-1; Wed, 20 Jan 2021 17:24:35 -0500 X-MC-Unique: xDOzmqpON9-iOtFivxqb4A-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 3708A8144E8; Wed, 20 Jan 2021 22:24:34 +0000 (UTC) Received: from [10.3.113.116] (ovpn-113-116.phx2.redhat.com [10.3.113.116]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 004E95D9EF; Wed, 20 Jan 2021 22:24:32 +0000 (UTC) Subject: Re: [PATCH v2 1/8] block/nbd: move initial connect to coroutine To: Vladimir Sementsov-Ogievskiy , qemu-block@nongnu.org References: <20201130134024.19212-1-vsementsov@virtuozzo.com> <20201130134024.19212-2-vsementsov@virtuozzo.com> From: Eric Blake Organization: Red Hat, Inc. Message-ID: <4a2d33f6-18ee-b8ff-a945-4ac6ce0406f4@redhat.com> Date: Wed, 20 Jan 2021 16:24:32 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.6.0 MIME-Version: 1.0 In-Reply-To: <20201130134024.19212-2-vsementsov@virtuozzo.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=eblake@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Received-SPF: pass client-ip=63.128.21.124; envelope-from=eblake@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -30 X-Spam_score: -3.1 X-Spam_bar: --- X-Spam_report: (-3.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.167, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, NICE_REPLY_A=-0.094, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kwolf@redhat.com, den@openvz.org, qemu-devel@nongnu.org, mreitz@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 11/30/20 7:40 AM, Vladimir Sementsov-Ogievskiy wrote: > We are going to implement reconnect-on-open. Let's reuse existing > reconnect loop. For this, do initial connect in connection coroutine. > > Signed-off-by: Vladimir Sementsov-Ogievskiy > --- > block/nbd.c | 94 ++++++++++++++++++++++++++++++----------------------- > 1 file changed, 53 insertions(+), 41 deletions(-) > > @@ -2279,6 +2268,29 @@ static int nbd_open(BlockDriverState *bs, QDict *options, int flags, > bdrv_inc_in_flight(bs); > aio_co_schedule(bdrv_get_aio_context(bs), s->connection_co); > > + if (qemu_in_coroutine()) { > + s->open_co = qemu_coroutine_self(); > + qemu_coroutine_yield(); > + } else { > + BDRV_POLL_WHILE(bs, s->state == NBD_CLIENT_OPENING); > + } > + > + if (s->state != NBD_CLIENT_CONNECTED && s->connect_status < 0) { > + /* > + * It's possible that state != NBD_CLIENT_CONNECTED, but connect_status > + * is 0. This means that initial connecting succeed, but failed later > + * (during BDRV_POLL_WHILE). It's a rare case, but it happen in iotest This means that starting the initial connection succeeded, but we failed later (during BDRV_POLL_WHILE). happens > + * 83. Let's don't care and just report success in this case: it not > + * much differs from the case when connection failed immediately after > + * succeeded open. We don't care, and just report success in this case, as it does not change our behavior from the case when the connection fails right after open succeeds. > + */ > + assert(s->connect_err); > + error_propagate(errp, s->connect_err); > + s->connect_err = NULL; > + nbd_clear_bdrvstate(s); > + return s->connect_status; > + } > + > return 0; > } > > Reviewed-by: Eric Blake -- Eric Blake, Principal Software Engineer Red Hat, Inc. +1-919-301-3226 Virtualization: qemu.org | libvirt.org