From: Jens Freimann Date: Tue, 29 Oct 2019 11:49:02 +0000 (+0100) Subject: migration: add new migration state wait-unplug X-Git-Tag: v4.2.0-rc0~23^2~6 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=c7e0acd5a3f87d4aabb7a702aff87f83fc3ce151;p=thirdparty%2Fqemu.git migration: add new migration state wait-unplug This patch adds a new migration state called wait-unplug. It is entered after the SETUP state if failover devices are present. It 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'. In the migration thread we query failover devices if they're are still pending the guest unplug. When all are unplugged the migration continues. If one device won't unplug migration will stay in wait_unplug state. Signed-off-by: Jens Freimann Reviewed-by: Dr. David Alan Gilbert Message-Id: <20191029114905.6856-9-jfreimann@redhat.com> Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- diff --git a/include/migration/vmstate.h b/include/migration/vmstate.h index b9ee563aa42..ac4f46a67de 100644 --- a/include/migration/vmstate.h +++ b/include/migration/vmstate.h @@ -186,6 +186,8 @@ 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 4133ed26844..354ad072fa5 100644 --- a/migration/migration.c +++ b/migration/migration.c @@ -52,6 +52,7 @@ #include "hw/qdev-properties.h" #include "monitor/monitor.h" #include "net/announce.h" +#include "qemu/queue.h" #define MAX_THROTTLE (32 << 20) /* Migration transfer speed throttling */ @@ -819,6 +820,7 @@ bool migration_is_setup_or_active(int state) case MIGRATION_STATUS_SETUP: case MIGRATION_STATUS_PRE_SWITCHOVER: case MIGRATION_STATUS_DEVICE: + case MIGRATION_STATUS_WAIT_UNPLUG: return true; default: @@ -954,6 +956,9 @@ 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; } @@ -1694,6 +1699,7 @@ 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(); @@ -3264,6 +3270,19 @@ static void *migration_thread(void *opaque) qemu_savevm_state_setup(s->to_dst_file); + if (qemu_savevm_nr_failover_devices()) { + migrate_set_state(&s->state, MIGRATION_STATUS_SETUP, + MIGRATION_STATUS_WAIT_UNPLUG); + + while (s->state == MIGRATION_STATUS_WAIT_UNPLUG && + qemu_savevm_state_guest_unplug_pending()) { + qemu_sem_timedwait(&s->wait_unplug_sem, 250); + } + + 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); @@ -3511,6 +3530,7 @@ static void migration_instance_finalize(Object *obj) qemu_mutex_destroy(&ms->qemu_file_lock); g_free(params->tls_hostname); g_free(params->tls_creds); + qemu_sem_destroy(&ms->wait_unplug_sem); qemu_sem_destroy(&ms->rate_limit_sem); qemu_sem_destroy(&ms->pause_sem); qemu_sem_destroy(&ms->postcopy_pause_sem); @@ -3556,6 +3576,7 @@ static void migration_instance_init(Object *obj) qemu_sem_init(&ms->postcopy_pause_rp_sem, 0); qemu_sem_init(&ms->rp_state.rp_sem, 0); qemu_sem_init(&ms->rate_limit_sem, 0); + qemu_sem_init(&ms->wait_unplug_sem, 0); qemu_mutex_init(&ms->qemu_file_lock); } diff --git a/migration/migration.h b/migration/migration.h index 4f2fe193dc5..79b3dda146f 100644 --- a/migration/migration.h +++ b/migration/migration.h @@ -206,6 +206,9 @@ struct MigrationState /* Flag set once the migration thread called bdrv_inactivate_all */ bool block_inactive; + /* Migration is waiting for guest to unplug device */ + QemuSemaphore wait_unplug_sem; + /* Migration is paused due to pause-before-switchover */ QemuSemaphore pause_sem; diff --git a/migration/savevm.c b/migration/savevm.c index 8d95e261f60..966a9c3bdbc 100644 --- a/migration/savevm.c +++ b/migration/savevm.c @@ -1113,6 +1113,37 @@ void qemu_savevm_state_header(QEMUFile *f) } } +int qemu_savevm_nr_failover_devices(void) +{ + SaveStateEntry *se; + int n = 0; + + QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { + if (se->vmsd && se->vmsd->dev_unplug_pending) { + n++; + } + } + + return n; +} + +bool qemu_savevm_state_guest_unplug_pending(void) +{ + SaveStateEntry *se; + int n = 0; + + QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { + if (!se->vmsd || !se->vmsd->dev_unplug_pending) { + continue; + } + if (se->vmsd->dev_unplug_pending(se->opaque)) { + n++; + } + } + + return n > 0; +} + void qemu_savevm_state_setup(QEMUFile *f) { SaveStateEntry *se; diff --git a/migration/savevm.h b/migration/savevm.h index 51a4b9caa8b..c42b9c80ee8 100644 --- a/migration/savevm.h +++ b/migration/savevm.h @@ -31,6 +31,8 @@ bool qemu_savevm_state_blocked(Error **errp); void qemu_savevm_state_setup(QEMUFile *f); +int qemu_savevm_nr_failover_devices(void); +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 e9e7a97c035..b7348d0c8bf 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: