From a2e308060512eb7d4ee00f7baddb7394d6e9e4e6 Mon Sep 17 00:00:00 2001
Message-Id: <a2e308060512eb7d4ee00f7baddb7394d6e9e4e6@dist-git>
From: Jiri Denemark <jdenemar@redhat.com>
Date: Mon, 10 Sep 2018 19:41:53 +0200
Subject: [PATCH] qemu: Pass running reason to RESUME event handler
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Whenever we get the RESUME event from QEMU, we change the state of the
affected domain to VIR_DOMAIN_RUNNING with VIR_DOMAIN_RUNNING_UNPAUSED
reason. This is fine if the domain is resumed unexpectedly, but when we
sent "cont" to QEMU we usually have a better reason for the state
change. The better reason is used in qemuProcessStartCPUs which also
sets the domain state to running if qemuMonitorStartCPUs reports
success. Thus we may end up with two state updates in a row, but the
final reason is correct.

This patch is a preparation for dropping the state change done in
qemuMonitorStartCPUs for which we need to pass the actual running reason
to the RESUME event handler and use it there instead of
VIR_DOMAIN_RUNNING_UNPAUSED.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
(cherry picked from commit 5dab984ed0cd0332e59d719420ab2f9d009b952f)

https://bugzilla.redhat.com/show_bug.cgi?id=1634758
https://bugzilla.redhat.com/show_bug.cgi?id=1634759

Conflicts:
	src/qemu/qemu_domain.h
            - nodenames code is not backported

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
---
 src/qemu/qemu_domain.h  |  4 ++++
 src/qemu/qemu_process.c | 23 +++++++++++++++++------
 2 files changed, 21 insertions(+), 6 deletions(-)

diff --git a/src/qemu/qemu_domain.h b/src/qemu/qemu_domain.h
index e748d78adb..6a96f27a5f 100644
--- a/src/qemu/qemu_domain.h
+++ b/src/qemu/qemu_domain.h
@@ -363,6 +363,10 @@ struct _qemuDomainObjPrivate {
 
     /* true if qemu-pr-helper process is running for the domain */
     bool prDaemonRunning;
+
+    /* qemuProcessStartCPUs stores the reason for starting vCPUs here for the
+     * RESUME event handler to use it */
+    virDomainRunningReason runningReason;
 };
 
 # define QEMU_DOMAIN_PRIVATE(vm) \
diff --git a/src/qemu/qemu_process.c b/src/qemu/qemu_process.c
index 26979faa72..7325bc4c90 100644
--- a/src/qemu/qemu_process.c
+++ b/src/qemu/qemu_process.c
@@ -692,21 +692,28 @@ qemuProcessHandleResume(qemuMonitorPtr mon ATTRIBUTE_UNUSED,
     virQEMUDriverPtr driver = opaque;
     virObjectEventPtr event = NULL;
     virQEMUDriverConfigPtr cfg = virQEMUDriverGetConfig(driver);
+    qemuDomainObjPrivatePtr priv;
+    virDomainRunningReason reason = VIR_DOMAIN_RUNNING_UNPAUSED;
 
     virObjectLock(vm);
-    if (virDomainObjGetState(vm, NULL) == VIR_DOMAIN_PAUSED) {
-        qemuDomainObjPrivatePtr priv = vm->privateData;
 
+    priv = vm->privateData;
+    if (priv->runningReason != VIR_DOMAIN_RUNNING_UNKNOWN) {
+        reason = priv->runningReason;
+        priv->runningReason = VIR_DOMAIN_RUNNING_UNKNOWN;
+    }
+
+    if (virDomainObjGetState(vm, NULL) == VIR_DOMAIN_PAUSED) {
         if (priv->gotShutdown) {
             VIR_DEBUG("Ignoring RESUME event after SHUTDOWN");
             goto unlock;
         }
 
-        VIR_DEBUG("Transitioned guest %s out of paused into resumed state",
-                  vm->def->name);
+        VIR_DEBUG("Transitioned guest %s out of paused into resumed state, "
+                  "reason '%s'",
+                  vm->def->name, virDomainRunningReasonTypeToString(reason));
 
-        virDomainObjSetState(vm, VIR_DOMAIN_RUNNING,
-                                 VIR_DOMAIN_RUNNING_UNPAUSED);
+        virDomainObjSetState(vm, VIR_DOMAIN_RUNNING, reason);
         event = virDomainEventLifecycleNewFromObj(vm,
                                          VIR_DOMAIN_EVENT_RESUMED,
                                          VIR_DOMAIN_EVENT_RESUMED_UNPAUSED);
@@ -3051,6 +3058,8 @@ qemuProcessStartCPUs(virQEMUDriverPtr driver, virDomainObjPtr vm,
     }
     VIR_FREE(priv->lockState);
 
+    priv->runningReason = reason;
+
     if (qemuDomainObjEnterMonitorAsync(driver, vm, asyncJob) < 0)
         goto release;
 
@@ -3068,6 +3077,7 @@ qemuProcessStartCPUs(virQEMUDriverPtr driver, virDomainObjPtr vm,
     return ret;
 
  release:
+    priv->runningReason = VIR_DOMAIN_RUNNING_UNKNOWN;
     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));
@@ -5928,6 +5938,7 @@ qemuProcessPrepareDomain(virQEMUDriverPtr driver,
     priv->monError = false;
     priv->monStart = 0;
     priv->gotShutdown = false;
+    priv->runningReason = VIR_DOMAIN_RUNNING_UNKNOWN;
 
     VIR_DEBUG("Updating guest CPU definition");
     if (qemuProcessUpdateGuestCPU(vm->def, priv->qemuCaps, caps, flags) < 0)
-- 
2.19.1