Memory Hotplug

热插内存主要流程

注册 callback

virConnectDomainEventRegisterAny
|– qemuConnectDomainEventRegisterAny
|– virDomainEventStateRegisterID(conn, driver->domainEventState, …)
|– virObjectEventStateRegisterID
|– virEventAddTimeout(-1, virObjectEventTimer, state)
|– virObjectEventCallbackListAddID <— 在conn中添加callback

添加事件

|– qemuDomainAttachDeviceLiveAndConfig
|– qemuDomainAttachDeviceLive
|– qemuDomainAttachMemory
|– virDomainMemoryInsert
|– event = virDomainEventDeviceAddedNewFromObj(vm, objalias); 构造event
|– virDomainEventDeviceAddedClass, VIR_DOMAIN_EVENT_ID_DEVICE_ADDED
|– virObjectEventStateQueue(driver->domainEventState, event); 等待分发
|– virObjectEventStateQueueRemote
|– virObjectEventQueuePush

分发事件

|– virObjectEventTimer
|– virObjectEventStateFlush <— Timer 到期之后会将调用该函数
|– virEventUpdateTimeout
|– virObjectEventStateQueueDispatch
|– virObjectEventStateDispatchCallbacks
|– 在callback池中找匹配的event_id，确定event对应的callback
|– event->dispatch(cb->conn, event, cb->cb, cb->opaque);
|– virObjectEventCallbackListPurgeMarked
|– virObjectEventStateCleanupTimer

调用callback的流程

{
    REMOTE_PROC_DOMAIN_EVENT_CALLBACK_DEVICE_ADDED,
    remoteDomainBuildEventCallbackDeviceAdded,
    sizeof(remote_domain_event_callback_device_added_msg),
    (xdrproc_t)xdr_remote_domain_event_callback_device_added_msg
}

事件的callback注册

static virNetClientProgramEvent remoteEvents[]

|– remoteDomainBuildEventCallbackDeviceAdded
|– virDomainEventDeviceAddedNewFromDom
|– virDomainEventDeviceAddedNew
|– virDomainEventNew
|– virObjectEventNew(klass, virDomainEventDispatchDefaultFunc, …) <— 这里注册了一个分发函数，找到对应的处理函数
|– virObjectEventStateQueueRemote