From patchwork Fri Aug 2 15:06:03 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jens Freimann X-Patchwork-Id: 1141253 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=redhat.com 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 ozlabs.org (Postfix) with ESMTPS id 460VvR2jrLz9s3Z for ; Sat, 3 Aug 2019 01:09:55 +1000 (AEST) Received: from localhost ([::1]:35594 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1htZBp-0004A2-FT for incoming@patchwork.ozlabs.org; Fri, 02 Aug 2019 11:09:53 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:47246) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1htZ8s-0006AN-FQ for qemu-devel@nongnu.org; Fri, 02 Aug 2019 11:06:51 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1htZ8r-0005Tq-43 for qemu-devel@nongnu.org; Fri, 02 Aug 2019 11:06:50 -0400 Received: from mx1.redhat.com ([209.132.183.28]:39280) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1htZ8q-0005TL-Rf for qemu-devel@nongnu.org; Fri, 02 Aug 2019 11:06:49 -0400 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 mx1.redhat.com (Postfix) with ESMTPS id 18BABC057EC0 for ; Fri, 2 Aug 2019 15:06:48 +0000 (UTC) Received: from localhost (dhcp-192-195.str.redhat.com [10.33.192.195]) by smtp.corp.redhat.com (Postfix) with ESMTPS id A889A5D9D3; Fri, 2 Aug 2019 15:06:47 +0000 (UTC) From: Jens Freimann To: qemu-devel@nongnu.org Date: Fri, 2 Aug 2019 17:06:03 +0200 Message-Id: <20190802150605.5880-8-jfreimann@redhat.com> In-Reply-To: <20190802150605.5880-1-jfreimann@redhat.com> References: <20190802150605.5880-1-jfreimann@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.32]); Fri, 02 Aug 2019 15:06:48 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH 7/9] migration: Add new migration state wait-unplug 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: pkrempa@redhat.com, berrange@redhat.com, ehabkost@redhat.com, mst@redhat.com, aadam@redhat.com, laine@redhat.com, ailan@redhat.com Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" This patch is not ready for inclusion yet, I'm looking for feedback/ideas on a particular problem. See below. This patch adds a new migration state called wait-unplug. It is entered after the SETUP state and will transition into ACTIVE once all devices were succesfully unplugged from the guest. So if a guest doesn't respond or takes long to honor the unplug request the user will see the migration state 'wait-unplug'. It adds a new function callback to VMStateDescription which is called for every device that implements it and reports its device_pending status. Now this loop in the migration thread: while (qemu_savevm_state_guest_unplug_pending()) { continue; } clearly needs a condition to terminate after a while/or a certain number of iterations. But I'm not sure what is a good solution. How much waiting time is acceptable for a migration? Signed-off-by: Jens Freimann --- include/migration/vmstate.h | 2 ++ migration/migration.c | 14 ++++++++++++++ migration/savevm.c | 18 ++++++++++++++++++ migration/savevm.h | 1 + qapi/migration.json | 5 ++++- 5 files changed, 39 insertions(+), 1 deletion(-) diff --git a/include/migration/vmstate.h b/include/migration/vmstate.h index c2bfa7a7f0..8b2a125c4c 100644 --- a/include/migration/vmstate.h +++ b/include/migration/vmstate.h @@ -187,6 +187,8 @@ struct VMStateDescription { int (*pre_save)(void *opaque); int (*post_save)(void *opaque); bool (*needed)(void *opaque); + bool (*dev_unplug_pending)(void *opaque); + const VMStateField *fields; const VMStateDescription **subsections; }; diff --git a/migration/migration.c b/migration/migration.c index 8a607fe1e2..a7d21b73fe 100644 --- a/migration/migration.c +++ b/migration/migration.c @@ -946,6 +946,9 @@ static void fill_source_migration_info(MigrationInfo *info) case MIGRATION_STATUS_CANCELLED: info->has_status = true; break; + case MIGRATION_STATUS_WAIT_UNPLUG: + info->has_status = true; + break; } info->status = s->state; } @@ -1680,6 +1683,7 @@ bool migration_is_idle(void) case MIGRATION_STATUS_COLO: case MIGRATION_STATUS_PRE_SWITCHOVER: case MIGRATION_STATUS_DEVICE: + case MIGRATION_STATUS_WAIT_UNPLUG: return false; case MIGRATION_STATUS__MAX: g_assert_not_reached(); @@ -1712,6 +1716,7 @@ void migrate_init(MigrationState *s) error_free(s->error); s->error = NULL; + /* go to WAIT_UNPLUG first? */ migrate_set_state(&s->state, MIGRATION_STATUS_NONE, MIGRATION_STATUS_SETUP); s->start_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); @@ -3218,6 +3223,15 @@ static void *migration_thread(void *opaque) qemu_savevm_state_setup(s->to_dst_file); + migrate_set_state(&s->state, MIGRATION_STATUS_SETUP, + MIGRATION_STATUS_WAIT_UNPLUG); + while (qemu_savevm_state_guest_unplug_pending()) { + continue; + } + migrate_set_state(&s->state, MIGRATION_STATUS_WAIT_UNPLUG, + MIGRATION_STATUS_ACTIVE); + + s->setup_time = qemu_clock_get_ms(QEMU_CLOCK_HOST) - setup_start; migrate_set_state(&s->state, MIGRATION_STATUS_SETUP, MIGRATION_STATUS_ACTIVE); diff --git a/migration/savevm.c b/migration/savevm.c index 79ed44d475..2bb54b3a8a 100644 --- a/migration/savevm.c +++ b/migration/savevm.c @@ -1085,6 +1085,24 @@ void qemu_savevm_state_header(QEMUFile *f) } } +bool qemu_savevm_state_guest_unplug_pending(void) +{ + SaveStateEntry *se; + bool ret = false; + + QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { + if (!se->vmsd || !se->vmsd->dev_unplug_pending) { + continue; + } + ret = se->vmsd->dev_unplug_pending(se->opaque); + if (ret) { + break; + } + } + + return ret; +} + void qemu_savevm_state_setup(QEMUFile *f) { SaveStateEntry *se; diff --git a/migration/savevm.h b/migration/savevm.h index 51a4b9caa8..ba64a7e271 100644 --- a/migration/savevm.h +++ b/migration/savevm.h @@ -31,6 +31,7 @@ bool qemu_savevm_state_blocked(Error **errp); void qemu_savevm_state_setup(QEMUFile *f); +bool qemu_savevm_state_guest_unplug_pending(void); int qemu_savevm_state_resume_prepare(MigrationState *s); void qemu_savevm_state_header(QEMUFile *f); int qemu_savevm_state_iterate(QEMUFile *f, bool postcopy); diff --git a/qapi/migration.json b/qapi/migration.json index d567ac9fc3..c42381a85f 100644 --- a/qapi/migration.json +++ b/qapi/migration.json @@ -133,6 +133,9 @@ # @device: During device serialisation when pause-before-switchover is enabled # (since 2.11) # +# @wait-unplug: wait for device unplug request by guest OS to be completed. +# (since 4.2) +# # Since: 2.3 # ## @@ -140,7 +143,7 @@ 'data': [ 'none', 'setup', 'cancelling', 'cancelled', 'active', 'postcopy-active', 'postcopy-paused', 'postcopy-recover', 'completed', 'failed', 'colo', - 'pre-switchover', 'device' ] } + 'pre-switchover', 'device', 'wait-unplug' ] } ## # @MigrationInfo: