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,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 08FF5C2B9F8 for ; Tue, 25 May 2021 10:28:04 +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 B3D32610FC for ; Tue, 25 May 2021 10:28:03 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B3D32610FC 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]:56528 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1llUI6-0003lP-Lb for qemu-devel@archiver.kernel.org; Tue, 25 May 2021 06:28:02 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:48254) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1llUH1-000336-Oo for qemu-devel@nongnu.org; Tue, 25 May 2021 06:26:55 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:36139) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1llUGz-0001I3-CK for qemu-devel@nongnu.org; Tue, 25 May 2021 06:26:55 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1621938412; 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=NicHkbJh2Rpk9ykgxlb6aXtPWUrgZKyOmqk+QQNx7AE=; b=i0S+O8LYWuOftnhoRpm3JE4tCOAVY3zeyI40ERXPYzfBMAVEEcaUIONZhw82S3JjLzvU6r 6BzXqtFRsQ3FcXC5OJVmOYbIxMflk5ARq/HAp5TK+E52cWVPTKqhN3IFhAV0tKPyhmnsS3 EFw1URt8ieTB/NRrq2306f/1IbtqPcY= 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-464-TteOZlVGOiCpbDQtZXde4A-1; Tue, 25 May 2021 06:26:50 -0400 X-MC-Unique: TteOZlVGOiCpbDQtZXde4A-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id B93F810082E1; Tue, 25 May 2021 10:26:49 +0000 (UTC) Received: from work-vm (ovpn-115-40.ams2.redhat.com [10.36.115.40]) by smtp.corp.redhat.com (Postfix) with ESMTPS id E7D8370581; Tue, 25 May 2021 10:26:48 +0000 (UTC) Date: Tue, 25 May 2021 11:26:46 +0100 From: "Dr. David Alan Gilbert" To: Li Zhijian Subject: Re: [PATCH v2 4/4] migration/rdma: source: poll cm_event from return path Message-ID: References: <20210525080552.28259-1-lizhijian@cn.fujitsu.com> <20210525080552.28259-4-lizhijian@cn.fujitsu.com> MIME-Version: 1.0 In-Reply-To: <20210525080552.28259-4-lizhijian@cn.fujitsu.com> User-Agent: Mutt/2.0.7 (2021-05-04) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=dgilbert@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Received-SPF: pass client-ip=170.10.133.124; envelope-from=dgilbert@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -31 X-Spam_score: -3.2 X-Spam_bar: --- X-Spam_report: (-3.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.371, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, 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=ham 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: qemu-devel@nongnu.org, quintela@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" * Li Zhijian (lizhijian@cn.fujitsu.com) wrote: > source side always blocks if postcopy is only enabled at source side. > users are not able to cancel this migration in this case. > > Let source side have chance to cancel this migration > > Signed-off-by: Li Zhijian > --- > V2: utilize poll to check cm event > --- > migration/rdma.c | 42 ++++++++++++++++++++++++++++++++++++++---- > 1 file changed, 38 insertions(+), 4 deletions(-) > > diff --git a/migration/rdma.c b/migration/rdma.c > index d829d08d076..f67e21b4f54 100644 > --- a/migration/rdma.c > +++ b/migration/rdma.c > @@ -36,6 +36,7 @@ > #include > #include "trace.h" > #include "qom/object.h" > +#include > > /* > * Print and error on both the Monitor and the Log file. > @@ -2460,7 +2461,36 @@ err_rdma_source_init: > return -1; > } > > -static int qemu_rdma_connect(RDMAContext *rdma, Error **errp) > +static int qemu_get_cm_event_timeout(RDMAContext *rdma, > + struct rdma_cm_event **cm_event, > + long msec, Error **errp) > +{ > + int ret; > + struct pollfd poll_fd = { > + .fd = rdma->channel->fd, > + .events = POLLIN, > + .revents = 0 > + }; > + > + do { > + ret = poll(&poll_fd, 1, msec); > + } while (ret < 0 && errno == EINTR); > + > + if (ret == 0) { > + ERROR(errp, "poll cm event timeout"); > + return -1; > + } else if (ret < 0) { > + ERROR(errp, "failed to pull cm event, errno=%i", errno); Typo: 'poll' - I can fix that. > + return -1; > + } else if (poll_fd.revents & POLLIN) { > + return rdma_get_cm_event(rdma->channel, cm_event); > + } else { > + ERROR(errp, "no POLLIN event, revent=%x", poll_fd.revents); > + return -1; > + } > +} > + > +static int qemu_rdma_connect(RDMAContext *rdma, Error **errp, bool return_path) > { > RDMACapabilities cap = { > .version = RDMA_CONTROL_VERSION_CURRENT, > @@ -2498,7 +2528,11 @@ static int qemu_rdma_connect(RDMAContext *rdma, Error **errp) > goto err_rdma_source_connect; > } > > - ret = rdma_get_cm_event(rdma->channel, &cm_event); > + if (return_path) { > + ret = qemu_get_cm_event_timeout(rdma, &cm_event, 5000, errp); Fixed timeouts are not a great fix; but I can't think of anything better; the only alternative would be to register the fd on the main thread's poll and get it to be called back when the event happened. But for now; Reviewed-by: Dr. David Alan Gilbert > + } else { > + ret = rdma_get_cm_event(rdma->channel, &cm_event); > + } > if (ret) { > perror("rdma_get_cm_event after rdma_connect"); > ERROR(errp, "connecting to destination!"); > @@ -4111,7 +4145,7 @@ void rdma_start_outgoing_migration(void *opaque, > } > > trace_rdma_start_outgoing_migration_after_rdma_source_init(); > - ret = qemu_rdma_connect(rdma, errp); > + ret = qemu_rdma_connect(rdma, errp, false); > > if (ret) { > goto err; > @@ -4132,7 +4166,7 @@ void rdma_start_outgoing_migration(void *opaque, > goto return_path_err; > } > > - ret = qemu_rdma_connect(rdma_return_path, errp); > + ret = qemu_rdma_connect(rdma_return_path, errp, true); > > if (ret) { > goto return_path_err; > -- > 2.30.2 > > > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK