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=-5.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,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 E84B5C47256 for ; Fri, 1 May 2020 22:09:40 +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 AAA5620857 for ; Fri, 1 May 2020 22:09:40 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="STWHUEnB" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AAA5620857 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]:40050 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jUdql-00020Q-T8 for qemu-devel@archiver.kernel.org; Fri, 01 May 2020 18:09:39 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:59894) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jUdpQ-0001Lc-Jg for qemu-devel@nongnu.org; Fri, 01 May 2020 18:08:17 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.90_1) (envelope-from ) id 1jUdpP-0001YC-QT for qemu-devel@nongnu.org; Fri, 01 May 2020 18:08:16 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:42363 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1jUdpP-0001Wm-Bx for qemu-devel@nongnu.org; Fri, 01 May 2020 18:08:15 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1588370891; 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=pMVEiYMQfHRYcIfWEnvDyJBUSxvjXO6LpDCAoABlzyg=; b=STWHUEnBv/EqaQCuc6lRiM2DGZbq/IDp8IjZa1yvS34lBL70z7la6Z5Bf7oMOeN+yKjBpw 1L+UAug3cG4xApv9WwEOWvRNbtaLWkTj9T+Tjx2wH19dyVhcB3NPGTow5AzHc5eYOV4mqv lHnCABaP6gvkqWfB64tu7hk3gZYH530= 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-341-9SSXap_4MzCGX-fDkJhG-w-1; Fri, 01 May 2020 18:08:09 -0400 X-MC-Unique: 9SSXap_4MzCGX-fDkJhG-w-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 0EA20EC1A8; Fri, 1 May 2020 22:08:07 +0000 (UTC) Received: from [10.3.114.73] (ovpn-114-73.phx2.redhat.com [10.3.114.73]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 57DBA6152C; Fri, 1 May 2020 22:08:02 +0000 (UTC) Subject: Re: [PATCH v2 9/9] block/io: expand in_flight inc/dec section: bdrv_make_zero To: Vladimir Sementsov-Ogievskiy , qemu-block@nongnu.org References: <20200427143907.5710-1-vsementsov@virtuozzo.com> <20200427143907.5710-10-vsementsov@virtuozzo.com> From: Eric Blake Organization: Red Hat, Inc. Message-ID: <191f526c-2fb3-d7d3-cf79-df0780e8ee22@redhat.com> Date: Fri, 1 May 2020 17:08:01 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.7.0 MIME-Version: 1.0 In-Reply-To: <20200427143907.5710-10-vsementsov@virtuozzo.com> Content-Language: en-US X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Received-SPF: pass client-ip=207.211.31.120; envelope-from=eblake@redhat.com; helo=us-smtp-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/05/01 17:26:01 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 207.211.31.120 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, fam@euphon.net, qemu-devel@nongnu.org, mreitz@redhat.com, stefanha@redhat.com, den@openvz.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 4/27/20 9:39 AM, Vladimir Sementsov-Ogievskiy wrote: > It's safer to expand in_flight request to start before enter to > coroutine in synchronous wrappers and end after BDRV_POLL_WHILE loop. > Note that qemu_coroutine_enter may only schedule the coroutine in some > circumstances. See my wording suggestions earlier in the series. > > bdrv_make_zero update includes refactoring: move the whole loop into > coroutine, which has additional benefit of not create/enter new > coroutine on each iteration. > > Signed-off-by: Vladimir Sementsov-Ogievskiy > --- > block/io.c | 54 +++++++++++++++++++++++++++++++++++++++++++++++++++--- > 1 file changed, 51 insertions(+), 3 deletions(-) > > +int bdrv_make_zero(BdrvChild *child, BdrvRequestFlags flags) > +{ > + int ret; > + > + bdrv_inc_in_flight(child->bs); > + > + if (qemu_in_coroutine()) { > + /* Fast-path if already in coroutine context */ > + ret = bdrv_do_make_zero(child, flags); > + } else { > + BdrvDoMakeZeroData data = { > + .child = child, > + .flags = flags, > + .done = false, Another case where the line '.done = false,' is optional, thanks to C semantics, but does not hurt to leave it in. Reviewed-by: Eric Blake -- Eric Blake, Principal Software Engineer Red Hat, Inc. +1-919-301-3226 Virtualization: qemu.org | libvirt.org