From 399039a6b1d07610294cc810ac7a01b51ff6b5cf Mon Sep 17 00:00:00 2001
From: Nikolay Shirokovskiy <nshirokovskiy@virtuozzo.com>
Date: Thu, 9 Jul 2020 11:12:26 +0300
Subject: [PATCH] qemu: implement driver's shutdown/shutdown wait methods
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On shutdown we just stop accepting new jobs for worker thread so that on
shutdown wait we can exit worker thread faster. Yes we basically stop
processing of events for VMs but we are going to do so anyway in case of daemon
shutdown.

At the same time synchronous event processing that some API calls may require
are still possible as per VM event loop is still running and we don't need
worker thread for synchronous event processing.

Signed-off-by: Nikolay Shirokovskiy <nshirokovskiy@virtuozzo.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
---
 src/qemu/qemu_driver.c | 32 ++++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index ce72e1021d..5ae030affe 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -1090,6 +1090,36 @@ qemuStateStop(void)
     return ret;
 }
 
+
+static int
+qemuStateShutdownPrepare(void)
+{
+    virThreadPoolStop(qemu_driver->workerPool);
+    return 0;
+}
+
+
+static int
+qemuDomainObjStopWorkerIter(virDomainObjPtr vm,
+                            void *opaque G_GNUC_UNUSED)
+{
+    virObjectLock(vm);
+    qemuDomainObjStopWorker(vm);
+    virObjectUnlock(vm);
+    return 0;
+}
+
+
+static int
+qemuStateShutdownWait(void)
+{
+    virDomainObjListForEach(qemu_driver->domains, false,
+                            qemuDomainObjStopWorkerIter, NULL);
+    virThreadPoolDrain(qemu_driver->workerPool);
+    return 0;
+}
+
+
 /**
  * qemuStateCleanup:
  *
@@ -20336,6 +20366,8 @@ static virStateDriver qemuStateDriver = {
     .stateCleanup = qemuStateCleanup,
     .stateReload = qemuStateReload,
     .stateStop = qemuStateStop,
+    .stateShutdownPrepare = qemuStateShutdownPrepare,
+    .stateShutdownWait = qemuStateShutdownWait,
 };
 
 int qemuRegister(void)