Diff to v1 [1]:
- fix mistake of dropping hunk that starts CPUs if snapshot was
  not successful. We still need it if halt upon snapshot is requested.

The is series is mostly about the first patch. The others patch are
minor cleanups.

[1] v1 version
https://listman.redhat.com/archives/libvir-list/2022-March/229437.html

Maxim Nestratov (1):
  qemu: don't pause vm when creating internal snapshot

Nikolay Shirokovskiy (2):
  qemu: remove excessive check in qemuSnapshotCreateActiveInternal
  qemu: remove unnecessary gotos in qemuSnapshotCreateActiveInternal

 src/qemu/qemu_snapshot.c | 24 +++++++-----------------
 1 file changed, 7 insertions(+), 17 deletions(-)

-- 
2.35.1

From: Maxim Nestratov <mnestratov@virtuozzo.com>

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@redhat.com>
Date:   Thu Feb 24 16:46:44 2011 +0100

    qemu: Stop guest CPUs before creating a snapshot

commit 6ed2c484f261fd8bd217f855b9e5e5f981e63f0a
Author: Luiz Capitulino <lcapitulino@redhat.com>
Date:   Tue Apr 27 20:35:59 2010 -0300

    QMP: Introduce RESUME event

Signed-off-by: Nikolay Shirokovskiy <nikolay.shirokovskiy@openvz.org>
---
 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