Re: [PATCH 06/10] qemu: Wire up MEMORY_DEVICE_SIZE_CHANGE event

As advertised in previous commit, this event is delivered to us when virtio-mem module changes the allocation inside the guest. It comes with one attribute - size - which holds the new size of the virtio-mem (well, allocated size), in bytes. Mind you, this is not necessarily the same number as 'requested size'. It almost certainly will be when sizing the memory up, but it might not be when sizing the memory down - the guest kernel might be unable to free some blocks. This actual size is reported in the domain XML as an output element only. Signed-off-by: Michal Privoznik <mprivozn(a)redhat.com&gt; ---

diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c index b6fe5e4436..74c897b53e 100644 --- a/src/conf/domain_conf.c +++ b/src/conf/domain_conf.c @@ -17320,6 +17320,21 @@ virDomainMemoryFindByDeviceInfo(virDomainDefPtr def, } +ssize_t +virDomainMemoryFindByDeviceAlias(virDomainDefPtr def, + const char *alias)

+{ + size_t i; + + for (i = 0; i < def->nmems; i++) { + if (STREQ_NULLABLE(def->mems[i]->info.alias, alias)) + return i; + } + + return -1; +} + + /** * virDomainMemoryInsert: *

diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c index fadf0240fc..d64eb4d399 100644 --- a/src/qemu/qemu_driver.c +++ b/src/qemu/qemu_driver.c @@ -4273,6 +4273,36 @@ processGuestCrashloadedEvent(virQEMUDriverPtr driver, } +static void +processMemoryDeviceSizeChange(virQEMUDriverPtr driver, + virDomainObjPtr vm, + qemuMonitorMemoryDeviceSizeChangePtr info) +{ + virDomainMemoryDefPtr mem = NULL; + ssize_t idx; + + if (qemuDomainObjBeginJob(driver, vm, QEMU_JOB_MODIFY) < 0) + return; + + if (!virDomainObjIsActive(vm)) { + VIR_DEBUG("Domain is not running"); + goto endjob; + } + + idx = virDomainMemoryFindByDeviceAlias(vm->def, info->devAlias); + if (idx < 0) { + VIR_DEBUG("Memory device '%s' not found", info->devAlias); + goto endjob; + } + + mem = vm->def->mems[idx];

+ mem->actualsize = VIR_DIV_UP(info->size, 1024); + + endjob: + qemuDomainObjEndJob(driver, vm); +} + + static void qemuProcessEventHandler(void *data, void *opaque) { struct qemuProcessEvent *processEvent = data;

diff --git a/src/qemu/qemu_monitor.c b/src/qemu/qemu_monitor.c index 6b3c1c2f5e..59f0265804 100644 --- a/src/qemu/qemu_monitor.c +++ b/src/qemu/qemu_monitor.c

@@ -4400,6 +4414,16 @@ qemuMonitorEventRdmaGidStatusFree(qemuMonitorRdmaGidStatusPtr info) } +void +qemuMonitorMemoryDeviceSizeChangeFree(qemuMonitorMemoryDeviceSizeChangePtr info) +{ + if (!info) + return; + + VIR_FREE(info->devAlias);

diff --git a/src/qemu/qemu_process.c b/src/qemu/qemu_process.c index f87a3c0f60..37cc6a28e5 100644 --- a/src/qemu/qemu_process.c +++ b/src/qemu/qemu_process.c @@ -1937,6 +1937,46 @@ qemuProcessHandleMemoryFailure(qemuMonitorPtr mon G_GNUC_UNUSED, } +static int +qemuProcessHandleMemoryDeviceSizeChange(qemuMonitorPtr mon G_GNUC_UNUSED, + virDomainObjPtr vm, + const char *devAlias, + unsigned long long size, + void *opaque) +{ + virQEMUDriverPtr driver = opaque; + struct qemuProcessEvent *processEvent = NULL; + qemuMonitorMemoryDeviceSizeChangePtr info = NULL; + int ret = -1; + + virObjectLock(vm); + + VIR_DEBUG("Memory device '%s' changed size to '%llu' in domain '%s'", + devAlias, size, vm->def->name); + + info = g_new0(qemuMonitorMemoryDeviceSizeChange, 1); + info->devAlias = g_strdup(devAlias); + info->size = size; + + processEvent = g_new0(struct qemuProcessEvent, 1); + processEvent->eventType = QEMU_PROCESS_EVENT_MEMORY_DEVICE_SIZE_CHANGE; + processEvent->vm = virObjectRef(vm); + processEvent->data = g_steal_pointer(&info); + + if (virThreadPoolSendJob(driver->workerPool, 0, processEvent) < 0) { + qemuProcessEventFree(processEvent); + virObjectUnref(vm); + goto cleanup; + } + + ret = 0; + cleanup: + qemuMonitorMemoryDeviceSizeChangeFree(info);

+ virObjectUnlock(vm); + return ret; +}