[PATCH v2 REBASE 1/3] qemu: don't pause vm when creating internal snapshot

From: Maxim Nestratov <mnestratov(a)virtuozzo.com&gt; The pause was introduced in [1] in ancient times when probably distro's QEMU does not have RESUME event. Yet the event was in the upstream QEMU at the time version according to [2]. So the event is supported since QEMU version 0.13 which is much older then oldest currently supported 2.11.0 version and we can remove manual pause/resume. Except for the halt case. [1] commit 346236fea97602e9e6529c5d41a32ed26b126082 Author: Jiri Denemark <jdenemar(a)redhat.com&gt; Date: Thu Feb 24 16:46:44 2011 +0100 qemu: Stop guest CPUs before creating a snapshot commit 6ed2c484f261fd8bd217f855b9e5e5f981e63f0a Author: Luiz Capitulino <lcapitulino(a)redhat.com&gt; Date: Tue Apr 27 20:35:59 2010 -0300 QMP: Introduce RESUME event Signed-off-by: Nikolay Shirokovskiy <nikolay.shirokovskiy(a)openvz.org&gt; --- src/qemu/qemu_snapshot.c | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-) diff --git a/src/qemu/qemu_snapshot.c b/src/qemu/qemu_snapshot.c index b62fab7bb3..fc5b6dc7ce 100644 --- a/src/qemu/qemu_snapshot.c +++ b/src/qemu/qemu_snapshot.c @@ -293,16 +293,13 @@ qemuSnapshotCreateActiveInternal(virQEMUDriver *driver, virObjectEvent *event = NULL; bool resume = false; virDomainSnapshotDef *snapdef = virDomainSnapshotObjGetDef(snap); + bool halt = !!(flags & VIR_DOMAIN_SNAPSHOT_CREATE_HALT); int ret = -1; if (!qemuMigrationSrcIsAllowed(driver, vm, false, 0)) goto cleanup; - if (virDomainObjGetState(vm, NULL) == VIR_DOMAIN_RUNNING) { - /* savevm monitor command pauses the domain emitting an event which - * confuses libvirt since it's not notified when qemu resumes the - * domain. Thus we stop and start CPUs ourselves. - */ + if (halt) { if (qemuProcessStopCPUs(driver, vm, VIR_DOMAIN_PAUSED_SAVE, VIR_ASYNC_JOB_SNAPSHOT) < 0) goto cleanup; @@ -329,7 +326,7 @@ qemuSnapshotCreateActiveInternal(virQEMUDriver *driver, if (!(snapdef->cookie = (virObject *) qemuDomainSaveCookieNew(vm))) goto cleanup; - if (flags & VIR_DOMAIN_SNAPSHOT_CREATE_HALT) { + if (halt) { event = virDomainEventLifecycleNewFromObj(vm, VIR_DOMAIN_EVENT_STOPPED, VIR_DOMAIN_EVENT_STOPPED_FROM_SNAPSHOT); qemuProcessStop(driver, vm, VIR_DOMAIN_SHUTOFF_FROM_SNAPSHOT, -- 2.35.1