qemu: Don't duplicate suspend events and state changes

Since the STOP event handler can use the pausedReason as sent to
qemuProcessStopCPUs, we no longer need to send duplicate suspended
lifecycle events because we know what caused the stop along with extra
details. This processing allows us to also remove the duplicated state
change from qemuProcessStopCPUs.

Reviewed-by: John Ferlan <jferlan@redhat.com>
Signed-off-by: Nikolay Shirokovskiy <nshirokovskiy@virtuozzo.com>

src/qemu/qemu_driver.c

@@ -1773,10 +1773,8 @@ static int qemuDomainSuspend(virDomainPtr dom)
     virQEMUDriverPtr driver = dom->conn->privateData;
     virDomainObjPtr vm;
     int ret = -1;
-    virObjectEventPtr event = NULL;
     qemuDomainObjPrivatePtr priv;
     virDomainPausedReason reason;
-    int eventDetail;
     int state;
     virQEMUDriverConfigPtr cfg = NULL;
 
@@ -1795,16 +1793,12 @@ static int qemuDomainSuspend(virDomainPtr dom)
     if (virDomainObjCheckActive(vm) < 0)
         goto endjob;
 
-    if (priv->job.asyncJob == QEMU_ASYNC_JOB_MIGRATION_OUT) {
+    if (priv->job.asyncJob == QEMU_ASYNC_JOB_MIGRATION_OUT)
         reason = VIR_DOMAIN_PAUSED_MIGRATION;
-        eventDetail = VIR_DOMAIN_EVENT_SUSPENDED_MIGRATED;
+    else if (priv->job.asyncJob == QEMU_ASYNC_JOB_SNAPSHOT)
-    } else if (priv->job.asyncJob == QEMU_ASYNC_JOB_SNAPSHOT) {
         reason = VIR_DOMAIN_PAUSED_SNAPSHOT;
-        eventDetail = -1; /* don't create lifecycle events when doing snapshot */
+    else
-    } else {
         reason = VIR_DOMAIN_PAUSED_USER;
-        eventDetail = VIR_DOMAIN_EVENT_SUSPENDED_PAUSED;
-    }
 
     state = virDomainObjGetState(vm, NULL);
     if (state == VIR_DOMAIN_PMSUSPENDED) {
@@ -1814,12 +1808,6 @@ static int qemuDomainSuspend(virDomainPtr dom)
     } else if (state != VIR_DOMAIN_PAUSED) {
         if (qemuProcessStopCPUs(driver, vm, reason, QEMU_ASYNC_JOB_NONE) < 0)
             goto endjob;
-
-        if (eventDetail >= 0) {
-            event = virDomainEventLifecycleNewFromObj(vm,
-                                             VIR_DOMAIN_EVENT_SUSPENDED,
-                                             eventDetail);
-        }
     }
     if (virDomainSaveStatus(driver->xmlopt, cfg->stateDir, vm, driver->caps) < 0)
         goto endjob;
@@ -1831,7 +1819,6 @@ static int qemuDomainSuspend(virDomainPtr dom)
  cleanup:
     virDomainObjEndAPI(&vm);
 
-    virObjectEventStateQueue(driver->domainEventState, event);
     virObjectUnref(cfg);
     return ret;
 }
@@ -16453,13 +16440,6 @@ qemuDomainRevertToSnapshot(virDomainSnapshotPtr snapshot,
                                         VIR_DOMAIN_PAUSED_FROM_SNAPSHOT,
                                         QEMU_ASYNC_JOB_START) < 0)
                     goto endjob;
-                /* Create an event now in case the restore fails, so
-                 * that user will be alerted that they are now paused.
-                 * If restore later succeeds, we might replace this. */
-                detail = VIR_DOMAIN_EVENT_SUSPENDED_FROM_SNAPSHOT;
-                event = virDomainEventLifecycleNewFromObj(vm,
-                                                 VIR_DOMAIN_EVENT_SUSPENDED,
-                                                 detail);
                 if (!virDomainObjIsActive(vm)) {
                     virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                                    _("guest unexpectedly quit"));

src/qemu/qemu_migration.c

@@ -1269,29 +1269,6 @@ qemuMigrationSrcIsSafe(virDomainDefPtr def,
     return true;
 }
 
-/** qemuMigrationSrcSetOffline
- * Pause domain for non-live migration.
- */
-int
-qemuMigrationSrcSetOffline(virQEMUDriverPtr driver,
-                           virDomainObjPtr vm)
-{
-    int ret;
-    VIR_DEBUG("driver=%p vm=%p", driver, vm);
-    ret = qemuProcessStopCPUs(driver, vm, VIR_DOMAIN_PAUSED_MIGRATION,
-                              QEMU_ASYNC_JOB_MIGRATION_OUT);
-    if (ret == 0) {
-        virObjectEventPtr event;
-
-        event = virDomainEventLifecycleNewFromObj(vm,
-                                         VIR_DOMAIN_EVENT_SUSPENDED,
-                                         VIR_DOMAIN_EVENT_SUSPENDED_MIGRATED);
-        virObjectEventStateQueue(driver->domainEventState, event);
-    }
-
-    return ret;
-}
-
 
 void
 qemuMigrationAnyPostcopyFailed(virQEMUDriverPtr driver,
@@ -1314,19 +1291,10 @@ qemuMigrationAnyPostcopyFailed(virQEMUDriverPtr driver,
              "leaving the domain paused", vm->def->name);
 
     if (state == VIR_DOMAIN_RUNNING) {
-        virObjectEventPtr event;
-
         if (qemuProcessStopCPUs(driver, vm,
                                 VIR_DOMAIN_PAUSED_POSTCOPY_FAILED,
-                                QEMU_ASYNC_JOB_MIGRATION_IN) < 0) {
+                                QEMU_ASYNC_JOB_MIGRATION_IN) < 0)
             VIR_WARN("Unable to pause guest CPUs for %s", vm->def->name);
-            return;
-        }
-
-        event = virDomainEventLifecycleNewFromObj(vm,
-                                VIR_DOMAIN_EVENT_SUSPENDED,
-                                VIR_DOMAIN_EVENT_SUSPENDED_POSTCOPY_FAILED);
-        virObjectEventStateQueue(driver->domainEventState, event);
     } else {
         virDomainObjSetState(vm, VIR_DOMAIN_PAUSED,
                              VIR_DOMAIN_PAUSED_POSTCOPY_FAILED);
@@ -3532,10 +3500,11 @@ qemuMigrationSrcRun(virQEMUDriverPtr driver,
         }
     }
 
-    /* Before EnterMonitor, since qemuMigrationSetOffline already does that */
+    /* Before EnterMonitor, since already qemuProcessStopCPUs does that */
     if (!(flags & VIR_MIGRATE_LIVE) &&
         virDomainObjGetState(vm, NULL) == VIR_DOMAIN_RUNNING) {
-        if (qemuMigrationSrcSetOffline(driver, vm) < 0)
+        if (qemuProcessStopCPUs(driver, vm, VIR_DOMAIN_PAUSED_MIGRATION,
+                                QEMU_ASYNC_JOB_MIGRATION_OUT) < 0)
             goto error;
     }
 
@@ -3645,7 +3614,8 @@ qemuMigrationSrcRun(virQEMUDriverPtr driver,
                 goto error;
         }
     } else if (virDomainObjGetState(vm, NULL) == VIR_DOMAIN_RUNNING &&
-               qemuMigrationSrcSetOffline(driver, vm) < 0) {
+               qemuProcessStopCPUs(driver, vm, VIR_DOMAIN_PAUSED_MIGRATION,
+                                   QEMU_ASYNC_JOB_MIGRATION_OUT) < 0) {
         goto error;
     }
 

src/qemu/qemu_migration.h

@@ -102,10 +102,6 @@ typedef enum {
 } qemuMigrationJobPhase;
 VIR_ENUM_DECL(qemuMigrationJobPhase);
 
-int
-qemuMigrationSrcSetOffline(virQEMUDriverPtr driver,
-                           virDomainObjPtr vm);
-
 char *
 qemuMigrationSrcBegin(virConnectPtr conn,
                       virDomainObjPtr vm,

src/qemu/qemu_process.c

@@ -3255,7 +3255,11 @@ int qemuProcessStopCPUs(virQEMUDriverPtr driver,
     if (priv->job.current)
         ignore_value(virTimeMillisNow(&priv->job.current->stopped));
 
-    virDomainObjSetState(vm, VIR_DOMAIN_PAUSED, reason);
+    /* The STOP event handler will change the domain state with the reason
+     * saved in priv->pausedReason and it will also emit corresponding domain
+     * lifecycle event.
+     */
+
     if (virDomainLockProcessPause(driver->lockManager, vm, &priv->lockState) < 0)
         VIR_WARN("Unable to release lease on %s", vm->def->name);
     VIR_DEBUG("Preserving lock state '%s'", NULLSTR(priv->lockState));