1be8d8537SStefan Hajnoczi /* 2be8d8537SStefan Hajnoczi * Event loop thread 3be8d8537SStefan Hajnoczi * 4be8d8537SStefan Hajnoczi * Copyright Red Hat Inc., 2013 5be8d8537SStefan Hajnoczi * 6be8d8537SStefan Hajnoczi * Authors: 7be8d8537SStefan Hajnoczi * Stefan Hajnoczi <stefanha@redhat.com> 8be8d8537SStefan Hajnoczi * 9be8d8537SStefan Hajnoczi * This work is licensed under the terms of the GNU GPL, version 2 or later. 10be8d8537SStefan Hajnoczi * See the COPYING file in the top-level directory. 11be8d8537SStefan Hajnoczi * 12be8d8537SStefan Hajnoczi */ 13be8d8537SStefan Hajnoczi 14d38ea87aSPeter Maydell #include "qemu/osdep.h" 15be8d8537SStefan Hajnoczi #include "qom/object.h" 16be8d8537SStefan Hajnoczi #include "qom/object_interfaces.h" 17be8d8537SStefan Hajnoczi #include "qemu/module.h" 18be8d8537SStefan Hajnoczi #include "block/aio.h" 19be8d8537SStefan Hajnoczi #include "sysemu/iothread.h" 20dc3dd0d2SStefan Hajnoczi #include "qmp-commands.h" 212f78e491SChrysostomos Nanakos #include "qemu/error-report.h" 22ab28bd23SPaolo Bonzini #include "qemu/rcu.h" 23*e4370165SPaolo Bonzini #include "qemu/main-loop.h" 24be8d8537SStefan Hajnoczi 25be8d8537SStefan Hajnoczi typedef ObjectClass IOThreadClass; 26be8d8537SStefan Hajnoczi 27be8d8537SStefan Hajnoczi #define IOTHREAD_GET_CLASS(obj) \ 28be8d8537SStefan Hajnoczi OBJECT_GET_CLASS(IOThreadClass, obj, TYPE_IOTHREAD) 29be8d8537SStefan Hajnoczi #define IOTHREAD_CLASS(klass) \ 30be8d8537SStefan Hajnoczi OBJECT_CLASS_CHECK(IOThreadClass, klass, TYPE_IOTHREAD) 31be8d8537SStefan Hajnoczi 32*e4370165SPaolo Bonzini static __thread IOThread *my_iothread; 33*e4370165SPaolo Bonzini 34*e4370165SPaolo Bonzini AioContext *qemu_get_current_aio_context(void) 35*e4370165SPaolo Bonzini { 36*e4370165SPaolo Bonzini return my_iothread ? my_iothread->ctx : qemu_get_aio_context(); 37*e4370165SPaolo Bonzini } 38*e4370165SPaolo Bonzini 39be8d8537SStefan Hajnoczi static void *iothread_run(void *opaque) 40be8d8537SStefan Hajnoczi { 41be8d8537SStefan Hajnoczi IOThread *iothread = opaque; 42da5e1de9SStefan Hajnoczi bool blocking; 43be8d8537SStefan Hajnoczi 44ab28bd23SPaolo Bonzini rcu_register_thread(); 45ab28bd23SPaolo Bonzini 46*e4370165SPaolo Bonzini my_iothread = iothread; 4788eb7c29SStefan Hajnoczi qemu_mutex_lock(&iothread->init_done_lock); 4888eb7c29SStefan Hajnoczi iothread->thread_id = qemu_get_thread_id(); 4988eb7c29SStefan Hajnoczi qemu_cond_signal(&iothread->init_done_cond); 5088eb7c29SStefan Hajnoczi qemu_mutex_unlock(&iothread->init_done_lock); 5188eb7c29SStefan Hajnoczi 52da5e1de9SStefan Hajnoczi while (!iothread->stopping) { 53da5e1de9SStefan Hajnoczi aio_context_acquire(iothread->ctx); 54da5e1de9SStefan Hajnoczi blocking = true; 55da5e1de9SStefan Hajnoczi while (!iothread->stopping && aio_poll(iothread->ctx, blocking)) { 56da5e1de9SStefan Hajnoczi /* Progress was made, keep going */ 57da5e1de9SStefan Hajnoczi blocking = false; 58da5e1de9SStefan Hajnoczi } 59da5e1de9SStefan Hajnoczi aio_context_release(iothread->ctx); 60be8d8537SStefan Hajnoczi } 61ab28bd23SPaolo Bonzini 62ab28bd23SPaolo Bonzini rcu_unregister_thread(); 63be8d8537SStefan Hajnoczi return NULL; 64be8d8537SStefan Hajnoczi } 65be8d8537SStefan Hajnoczi 66dce8921bSFam Zheng static int iothread_stop(Object *object, void *opaque) 67be8d8537SStefan Hajnoczi { 68dce8921bSFam Zheng IOThread *iothread; 69be8d8537SStefan Hajnoczi 70dce8921bSFam Zheng iothread = (IOThread *)object_dynamic_cast(object, TYPE_IOTHREAD); 71dce8921bSFam Zheng if (!iothread || !iothread->ctx) { 72dce8921bSFam Zheng return 0; 732f78e491SChrysostomos Nanakos } 74be8d8537SStefan Hajnoczi iothread->stopping = true; 75be8d8537SStefan Hajnoczi aio_notify(iothread->ctx); 76be8d8537SStefan Hajnoczi qemu_thread_join(&iothread->thread); 77dce8921bSFam Zheng return 0; 78dce8921bSFam Zheng } 79dce8921bSFam Zheng 80dce8921bSFam Zheng static void iothread_instance_finalize(Object *obj) 81dce8921bSFam Zheng { 82dce8921bSFam Zheng IOThread *iothread = IOTHREAD(obj); 83dce8921bSFam Zheng 84dce8921bSFam Zheng iothread_stop(obj, NULL); 8588eb7c29SStefan Hajnoczi qemu_cond_destroy(&iothread->init_done_cond); 8688eb7c29SStefan Hajnoczi qemu_mutex_destroy(&iothread->init_done_lock); 87eb7b5c35SLin Ma if (!iothread->ctx) { 88eb7b5c35SLin Ma return; 89eb7b5c35SLin Ma } 90be8d8537SStefan Hajnoczi aio_context_unref(iothread->ctx); 91be8d8537SStefan Hajnoczi } 92be8d8537SStefan Hajnoczi 93be8d8537SStefan Hajnoczi static void iothread_complete(UserCreatable *obj, Error **errp) 94be8d8537SStefan Hajnoczi { 952f78e491SChrysostomos Nanakos Error *local_error = NULL; 96be8d8537SStefan Hajnoczi IOThread *iothread = IOTHREAD(obj); 97d21e8776SPaolo Bonzini char *name, *thread_name; 98be8d8537SStefan Hajnoczi 99be8d8537SStefan Hajnoczi iothread->stopping = false; 10088eb7c29SStefan Hajnoczi iothread->thread_id = -1; 1012f78e491SChrysostomos Nanakos iothread->ctx = aio_context_new(&local_error); 1022f78e491SChrysostomos Nanakos if (!iothread->ctx) { 1032f78e491SChrysostomos Nanakos error_propagate(errp, local_error); 1042f78e491SChrysostomos Nanakos return; 1052f78e491SChrysostomos Nanakos } 10688eb7c29SStefan Hajnoczi 10788eb7c29SStefan Hajnoczi qemu_mutex_init(&iothread->init_done_lock); 10888eb7c29SStefan Hajnoczi qemu_cond_init(&iothread->init_done_cond); 109be8d8537SStefan Hajnoczi 110be8d8537SStefan Hajnoczi /* This assumes we are called from a thread with useful CPU affinity for us 111be8d8537SStefan Hajnoczi * to inherit. 112be8d8537SStefan Hajnoczi */ 113d21e8776SPaolo Bonzini name = object_get_canonical_path_component(OBJECT(obj)); 114d21e8776SPaolo Bonzini thread_name = g_strdup_printf("IO %s", name); 115d21e8776SPaolo Bonzini qemu_thread_create(&iothread->thread, thread_name, iothread_run, 116be8d8537SStefan Hajnoczi iothread, QEMU_THREAD_JOINABLE); 117d21e8776SPaolo Bonzini g_free(thread_name); 118d21e8776SPaolo Bonzini g_free(name); 11988eb7c29SStefan Hajnoczi 12088eb7c29SStefan Hajnoczi /* Wait for initialization to complete */ 12188eb7c29SStefan Hajnoczi qemu_mutex_lock(&iothread->init_done_lock); 12288eb7c29SStefan Hajnoczi while (iothread->thread_id == -1) { 12388eb7c29SStefan Hajnoczi qemu_cond_wait(&iothread->init_done_cond, 12488eb7c29SStefan Hajnoczi &iothread->init_done_lock); 12588eb7c29SStefan Hajnoczi } 12688eb7c29SStefan Hajnoczi qemu_mutex_unlock(&iothread->init_done_lock); 127be8d8537SStefan Hajnoczi } 128be8d8537SStefan Hajnoczi 129be8d8537SStefan Hajnoczi static void iothread_class_init(ObjectClass *klass, void *class_data) 130be8d8537SStefan Hajnoczi { 131be8d8537SStefan Hajnoczi UserCreatableClass *ucc = USER_CREATABLE_CLASS(klass); 132be8d8537SStefan Hajnoczi ucc->complete = iothread_complete; 133be8d8537SStefan Hajnoczi } 134be8d8537SStefan Hajnoczi 135be8d8537SStefan Hajnoczi static const TypeInfo iothread_info = { 136be8d8537SStefan Hajnoczi .name = TYPE_IOTHREAD, 137be8d8537SStefan Hajnoczi .parent = TYPE_OBJECT, 138be8d8537SStefan Hajnoczi .class_init = iothread_class_init, 139be8d8537SStefan Hajnoczi .instance_size = sizeof(IOThread), 140be8d8537SStefan Hajnoczi .instance_finalize = iothread_instance_finalize, 141be8d8537SStefan Hajnoczi .interfaces = (InterfaceInfo[]) { 142be8d8537SStefan Hajnoczi {TYPE_USER_CREATABLE}, 143be8d8537SStefan Hajnoczi {} 144be8d8537SStefan Hajnoczi }, 145be8d8537SStefan Hajnoczi }; 146be8d8537SStefan Hajnoczi 147be8d8537SStefan Hajnoczi static void iothread_register_types(void) 148be8d8537SStefan Hajnoczi { 149be8d8537SStefan Hajnoczi type_register_static(&iothread_info); 150be8d8537SStefan Hajnoczi } 151be8d8537SStefan Hajnoczi 152be8d8537SStefan Hajnoczi type_init(iothread_register_types) 153be8d8537SStefan Hajnoczi 154be8d8537SStefan Hajnoczi char *iothread_get_id(IOThread *iothread) 155be8d8537SStefan Hajnoczi { 156be8d8537SStefan Hajnoczi return object_get_canonical_path_component(OBJECT(iothread)); 157be8d8537SStefan Hajnoczi } 158be8d8537SStefan Hajnoczi 159be8d8537SStefan Hajnoczi AioContext *iothread_get_aio_context(IOThread *iothread) 160be8d8537SStefan Hajnoczi { 161be8d8537SStefan Hajnoczi return iothread->ctx; 162be8d8537SStefan Hajnoczi } 163dc3dd0d2SStefan Hajnoczi 164dc3dd0d2SStefan Hajnoczi static int query_one_iothread(Object *object, void *opaque) 165dc3dd0d2SStefan Hajnoczi { 166dc3dd0d2SStefan Hajnoczi IOThreadInfoList ***prev = opaque; 167dc3dd0d2SStefan Hajnoczi IOThreadInfoList *elem; 168dc3dd0d2SStefan Hajnoczi IOThreadInfo *info; 169dc3dd0d2SStefan Hajnoczi IOThread *iothread; 170dc3dd0d2SStefan Hajnoczi 171dc3dd0d2SStefan Hajnoczi iothread = (IOThread *)object_dynamic_cast(object, TYPE_IOTHREAD); 172dc3dd0d2SStefan Hajnoczi if (!iothread) { 173dc3dd0d2SStefan Hajnoczi return 0; 174dc3dd0d2SStefan Hajnoczi } 175dc3dd0d2SStefan Hajnoczi 176dc3dd0d2SStefan Hajnoczi info = g_new0(IOThreadInfo, 1); 177dc3dd0d2SStefan Hajnoczi info->id = iothread_get_id(iothread); 178dc3dd0d2SStefan Hajnoczi info->thread_id = iothread->thread_id; 179dc3dd0d2SStefan Hajnoczi 180dc3dd0d2SStefan Hajnoczi elem = g_new0(IOThreadInfoList, 1); 181dc3dd0d2SStefan Hajnoczi elem->value = info; 182dc3dd0d2SStefan Hajnoczi elem->next = NULL; 183dc3dd0d2SStefan Hajnoczi 184dc3dd0d2SStefan Hajnoczi **prev = elem; 185dc3dd0d2SStefan Hajnoczi *prev = &elem->next; 186dc3dd0d2SStefan Hajnoczi return 0; 187dc3dd0d2SStefan Hajnoczi } 188dc3dd0d2SStefan Hajnoczi 189dc3dd0d2SStefan Hajnoczi IOThreadInfoList *qmp_query_iothreads(Error **errp) 190dc3dd0d2SStefan Hajnoczi { 191dc3dd0d2SStefan Hajnoczi IOThreadInfoList *head = NULL; 192dc3dd0d2SStefan Hajnoczi IOThreadInfoList **prev = &head; 193bc2256c4SDaniel P. Berrange Object *container = object_get_objects_root(); 194dc3dd0d2SStefan Hajnoczi 195dc3dd0d2SStefan Hajnoczi object_child_foreach(container, query_one_iothread, &prev); 196dc3dd0d2SStefan Hajnoczi return head; 197dc3dd0d2SStefan Hajnoczi } 198dce8921bSFam Zheng 199dce8921bSFam Zheng void iothread_stop_all(void) 200dce8921bSFam Zheng { 201dce8921bSFam Zheng Object *container = object_get_objects_root(); 202dce8921bSFam Zheng 203dce8921bSFam Zheng object_child_foreach(container, iothread_stop, NULL); 204dce8921bSFam Zheng } 205