[libvirt] [PATCH 14/35] qemu: process: Refactor setup of memory ballooning

[Peter Krempa]

Since the monitor code now supports ullongs when setting balloon size,
drop the legacy code with overflow checking.

Additionally the comment mentioning that the job is treated as a sync
job does not make sense any more since the monitor is entered
asynchronously.
---
 src/qemu/qemu_process.c | 38 ++++++++++++++++----------------------
 1 file changed, 16 insertions(+), 22 deletions(-)

diff --git a/src/qemu/qemu_process.c b/src/qemu/qemu_process.c
index cc588d7..d5d9369 100644
--- a/src/qemu/qemu_process.c
+++ b/src/qemu/qemu_process.c
@@ -4270,8 +4270,6 @@ int qemuProcessStart(virConnectPtr conn,
     qemuDomainObjPrivatePtr priv = vm->privateData;
     virCommandPtr cmd = NULL;
     struct qemuProcessHookData hookData;
-    unsigned long cur_balloon;
-    int period = 0;
     size_t i;
     bool rawio_set = false;
     char *nodeset = NULL;
@@ -4880,28 +4878,24 @@ int qemuProcessStart(virConnectPtr conn,
     if (qemuDomainUpdateMemoryDeviceInfo(driver, vm, asyncJob) < 0)
         goto cleanup;

-    /* Technically, qemuProcessStart can be called from inside
-     * QEMU_ASYNC_JOB_MIGRATION_IN, but we are okay treating this like
-     * a sync job since no other job can call into the domain until
-     * migration completes.  */
     VIR_DEBUG("Setting initial memory amount");
-    cur_balloon = vm->def->mem.cur_balloon;
-    if (cur_balloon != vm->def->mem.cur_balloon) {
-        virReportError(VIR_ERR_OVERFLOW,
-                       _("unable to set balloon to %lld"),
-                       vm->def->mem.cur_balloon);
-        goto cleanup;
+    if (vm->def->memballoon &&
+        vm->def->memballoon->model != VIR_DOMAIN_MEMBALLOON_MODEL_NONE) {
+        unsigned long long balloon = vm->def->mem.cur_balloon;
+        int period = vm->def->memballoon->period;
+
+        if (qemuDomainObjEnterMonitorAsync(driver, vm, asyncJob) < 0)
+            goto cleanup;
+
+        if (period)
+            qemuMonitorSetMemoryStatsPeriod(priv->mon, period);
+
+        if (qemuMonitorSetBalloon(priv->mon, balloon) < 0)
+            goto exit_monitor;
+
+        if (qemuDomainObjExitMonitor(driver, vm) < 0)
+            goto cleanup;
     }
-    if (vm->def->memballoon && vm->def->memballoon->period)
-        period = vm->def->memballoon->period;
-    if (qemuDomainObjEnterMonitorAsync(driver, vm, asyncJob) < 0)
-        goto cleanup;
-    if (period)
-        qemuMonitorSetMemoryStatsPeriod(priv->mon, period);
-    if (qemuMonitorSetBalloon(priv->mon, cur_balloon) < 0)
-        goto exit_monitor;
-    if (qemuDomainObjExitMonitor(driver, vm) < 0)
-        goto cleanup;

     VIR_DEBUG("Detecting actual memory size for video device");
     if (qemuProcessUpdateVideoRamSize(driver, vm, asyncJob) < 0)
-- 
2.4.1