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" 19d16341faSPaolo Bonzini #include "block/block.h" 20be8d8537SStefan Hajnoczi #include "sysemu/iothread.h" 21e688df6bSMarkus Armbruster #include "qapi/error.h" 22112ed241SMarkus Armbruster #include "qapi/qapi-commands-misc.h" 232f78e491SChrysostomos Nanakos #include "qemu/error-report.h" 24ab28bd23SPaolo Bonzini #include "qemu/rcu.h" 25e4370165SPaolo Bonzini #include "qemu/main-loop.h" 26be8d8537SStefan Hajnoczi 27be8d8537SStefan Hajnoczi typedef ObjectClass IOThreadClass; 28be8d8537SStefan Hajnoczi 29be8d8537SStefan Hajnoczi #define IOTHREAD_GET_CLASS(obj) \ 30be8d8537SStefan Hajnoczi OBJECT_GET_CLASS(IOThreadClass, obj, TYPE_IOTHREAD) 31be8d8537SStefan Hajnoczi #define IOTHREAD_CLASS(klass) \ 32be8d8537SStefan Hajnoczi OBJECT_CLASS_CHECK(IOThreadClass, klass, TYPE_IOTHREAD) 33be8d8537SStefan Hajnoczi 3490c558beSPeter Xu #ifdef CONFIG_POSIX 35cdd7abfdSStefan Hajnoczi /* Benchmark results from 2016 on NVMe SSD drives show max polling times around 36cdd7abfdSStefan Hajnoczi * 16-32 microseconds yield IOPS improvements for both iodepth=1 and iodepth=32 37cdd7abfdSStefan Hajnoczi * workloads. 38cdd7abfdSStefan Hajnoczi */ 39cdd7abfdSStefan Hajnoczi #define IOTHREAD_POLL_MAX_NS_DEFAULT 32768ULL 4090c558beSPeter Xu #else 4190c558beSPeter Xu #define IOTHREAD_POLL_MAX_NS_DEFAULT 0ULL 4290c558beSPeter Xu #endif 43cdd7abfdSStefan Hajnoczi 44e4370165SPaolo Bonzini static __thread IOThread *my_iothread; 45e4370165SPaolo Bonzini 46e4370165SPaolo Bonzini AioContext *qemu_get_current_aio_context(void) 47e4370165SPaolo Bonzini { 48e4370165SPaolo Bonzini return my_iothread ? my_iothread->ctx : qemu_get_aio_context(); 49e4370165SPaolo Bonzini } 50e4370165SPaolo Bonzini 51be8d8537SStefan Hajnoczi static void *iothread_run(void *opaque) 52be8d8537SStefan Hajnoczi { 53be8d8537SStefan Hajnoczi IOThread *iothread = opaque; 54be8d8537SStefan Hajnoczi 55ab28bd23SPaolo Bonzini rcu_register_thread(); 56ab28bd23SPaolo Bonzini 57e4370165SPaolo Bonzini my_iothread = iothread; 5888eb7c29SStefan Hajnoczi iothread->thread_id = qemu_get_thread_id(); 59*21c4d15bSPeter Xu qemu_sem_post(&iothread->init_done_sem); 6088eb7c29SStefan Hajnoczi 612362a28eSStefan Hajnoczi while (iothread->running) { 6265c1b5b6SPaolo Bonzini aio_poll(iothread->ctx, true); 63329163cbSWang Yong 646c95363dSPeter Xu /* 656c95363dSPeter Xu * We must check the running state again in case it was 666c95363dSPeter Xu * changed in previous aio_poll() 676c95363dSPeter Xu */ 686c95363dSPeter Xu if (iothread->running && atomic_read(&iothread->worker_context)) { 69329163cbSWang Yong GMainLoop *loop; 70329163cbSWang Yong 71329163cbSWang Yong g_main_context_push_thread_default(iothread->worker_context); 72329163cbSWang Yong iothread->main_loop = 73329163cbSWang Yong g_main_loop_new(iothread->worker_context, TRUE); 74329163cbSWang Yong loop = iothread->main_loop; 75329163cbSWang Yong 76329163cbSWang Yong g_main_loop_run(iothread->main_loop); 77329163cbSWang Yong iothread->main_loop = NULL; 78329163cbSWang Yong g_main_loop_unref(loop); 79329163cbSWang Yong 80329163cbSWang Yong g_main_context_pop_thread_default(iothread->worker_context); 81329163cbSWang Yong } 82be8d8537SStefan Hajnoczi } 83ab28bd23SPaolo Bonzini 84ab28bd23SPaolo Bonzini rcu_unregister_thread(); 85be8d8537SStefan Hajnoczi return NULL; 86be8d8537SStefan Hajnoczi } 87be8d8537SStefan Hajnoczi 882362a28eSStefan Hajnoczi /* Runs in iothread_run() thread */ 892362a28eSStefan Hajnoczi static void iothread_stop_bh(void *opaque) 902362a28eSStefan Hajnoczi { 912362a28eSStefan Hajnoczi IOThread *iothread = opaque; 922362a28eSStefan Hajnoczi 932362a28eSStefan Hajnoczi iothread->running = false; /* stop iothread_run() */ 942362a28eSStefan Hajnoczi 952362a28eSStefan Hajnoczi if (iothread->main_loop) { 962362a28eSStefan Hajnoczi g_main_loop_quit(iothread->main_loop); 972362a28eSStefan Hajnoczi } 982362a28eSStefan Hajnoczi } 992362a28eSStefan Hajnoczi 10082d90705SPeter Xu void iothread_stop(IOThread *iothread) 101be8d8537SStefan Hajnoczi { 10282d90705SPeter Xu if (!iothread->ctx || iothread->stopping) { 10382d90705SPeter Xu return; 1042f78e491SChrysostomos Nanakos } 105be8d8537SStefan Hajnoczi iothread->stopping = true; 1062362a28eSStefan Hajnoczi aio_bh_schedule_oneshot(iothread->ctx, iothread_stop_bh, iothread); 107be8d8537SStefan Hajnoczi qemu_thread_join(&iothread->thread); 10882d90705SPeter Xu } 10982d90705SPeter Xu 110cdd7abfdSStefan Hajnoczi static void iothread_instance_init(Object *obj) 111cdd7abfdSStefan Hajnoczi { 112cdd7abfdSStefan Hajnoczi IOThread *iothread = IOTHREAD(obj); 113cdd7abfdSStefan Hajnoczi 114cdd7abfdSStefan Hajnoczi iothread->poll_max_ns = IOTHREAD_POLL_MAX_NS_DEFAULT; 11514a2d118SMarc-André Lureau iothread->thread_id = -1; 116*21c4d15bSPeter Xu qemu_sem_init(&iothread->init_done_sem, 0); 117cdd7abfdSStefan Hajnoczi } 118cdd7abfdSStefan Hajnoczi 119dce8921bSFam Zheng static void iothread_instance_finalize(Object *obj) 120dce8921bSFam Zheng { 121dce8921bSFam Zheng IOThread *iothread = IOTHREAD(obj); 122dce8921bSFam Zheng 12382d90705SPeter Xu iothread_stop(iothread); 12414a2d118SMarc-André Lureau 12515544349SPeter Xu /* 12615544349SPeter Xu * Before glib2 2.33.10, there is a glib2 bug that GSource context 12715544349SPeter Xu * pointer may not be cleared even if the context has already been 12815544349SPeter Xu * destroyed (while it should). Here let's free the AIO context 12915544349SPeter Xu * earlier to bypass that glib bug. 13015544349SPeter Xu * 13115544349SPeter Xu * We can remove this comment after the minimum supported glib2 13215544349SPeter Xu * version boosts to 2.33.10. Before that, let's free the 13315544349SPeter Xu * GSources first before destroying any GMainContext. 13415544349SPeter Xu */ 13515544349SPeter Xu if (iothread->ctx) { 13615544349SPeter Xu aio_context_unref(iothread->ctx); 13715544349SPeter Xu iothread->ctx = NULL; 13815544349SPeter Xu } 1395b3ac23fSPeter Xu if (iothread->worker_context) { 1405b3ac23fSPeter Xu g_main_context_unref(iothread->worker_context); 1415b3ac23fSPeter Xu iothread->worker_context = NULL; 1425b3ac23fSPeter Xu } 143*21c4d15bSPeter Xu qemu_sem_destroy(&iothread->init_done_sem); 144be8d8537SStefan Hajnoczi } 145be8d8537SStefan Hajnoczi 146be8d8537SStefan Hajnoczi static void iothread_complete(UserCreatable *obj, Error **errp) 147be8d8537SStefan Hajnoczi { 1482f78e491SChrysostomos Nanakos Error *local_error = NULL; 149be8d8537SStefan Hajnoczi IOThread *iothread = IOTHREAD(obj); 150d21e8776SPaolo Bonzini char *name, *thread_name; 151be8d8537SStefan Hajnoczi 152be8d8537SStefan Hajnoczi iothread->stopping = false; 1532362a28eSStefan Hajnoczi iothread->running = true; 1542f78e491SChrysostomos Nanakos iothread->ctx = aio_context_new(&local_error); 1552f78e491SChrysostomos Nanakos if (!iothread->ctx) { 1562f78e491SChrysostomos Nanakos error_propagate(errp, local_error); 1572f78e491SChrysostomos Nanakos return; 1582f78e491SChrysostomos Nanakos } 15988eb7c29SStefan Hajnoczi 1605e5db499SStefan Hajnoczi aio_context_set_poll_params(iothread->ctx, 1615e5db499SStefan Hajnoczi iothread->poll_max_ns, 1625e5db499SStefan Hajnoczi iothread->poll_grow, 1635e5db499SStefan Hajnoczi iothread->poll_shrink, 1640d9d86fbSStefan Hajnoczi &local_error); 1650d9d86fbSStefan Hajnoczi if (local_error) { 1660d9d86fbSStefan Hajnoczi error_propagate(errp, local_error); 1670d9d86fbSStefan Hajnoczi aio_context_unref(iothread->ctx); 1680d9d86fbSStefan Hajnoczi iothread->ctx = NULL; 1690d9d86fbSStefan Hajnoczi return; 1700d9d86fbSStefan Hajnoczi } 1710d9d86fbSStefan Hajnoczi 172329163cbSWang Yong iothread->once = (GOnce) G_ONCE_INIT; 173be8d8537SStefan Hajnoczi 174be8d8537SStefan Hajnoczi /* This assumes we are called from a thread with useful CPU affinity for us 175be8d8537SStefan Hajnoczi * to inherit. 176be8d8537SStefan Hajnoczi */ 177d21e8776SPaolo Bonzini name = object_get_canonical_path_component(OBJECT(obj)); 178d21e8776SPaolo Bonzini thread_name = g_strdup_printf("IO %s", name); 179d21e8776SPaolo Bonzini qemu_thread_create(&iothread->thread, thread_name, iothread_run, 180be8d8537SStefan Hajnoczi iothread, QEMU_THREAD_JOINABLE); 181d21e8776SPaolo Bonzini g_free(thread_name); 182d21e8776SPaolo Bonzini g_free(name); 18388eb7c29SStefan Hajnoczi 18488eb7c29SStefan Hajnoczi /* Wait for initialization to complete */ 18588eb7c29SStefan Hajnoczi while (iothread->thread_id == -1) { 186*21c4d15bSPeter Xu qemu_sem_wait(&iothread->init_done_sem); 18788eb7c29SStefan Hajnoczi } 188be8d8537SStefan Hajnoczi } 189be8d8537SStefan Hajnoczi 1905e5db499SStefan Hajnoczi typedef struct { 1915e5db499SStefan Hajnoczi const char *name; 1925e5db499SStefan Hajnoczi ptrdiff_t offset; /* field's byte offset in IOThread struct */ 1935e5db499SStefan Hajnoczi } PollParamInfo; 1945e5db499SStefan Hajnoczi 1955e5db499SStefan Hajnoczi static PollParamInfo poll_max_ns_info = { 1965e5db499SStefan Hajnoczi "poll-max-ns", offsetof(IOThread, poll_max_ns), 1975e5db499SStefan Hajnoczi }; 1985e5db499SStefan Hajnoczi static PollParamInfo poll_grow_info = { 1995e5db499SStefan Hajnoczi "poll-grow", offsetof(IOThread, poll_grow), 2005e5db499SStefan Hajnoczi }; 2015e5db499SStefan Hajnoczi static PollParamInfo poll_shrink_info = { 2025e5db499SStefan Hajnoczi "poll-shrink", offsetof(IOThread, poll_shrink), 2035e5db499SStefan Hajnoczi }; 2045e5db499SStefan Hajnoczi 2055e5db499SStefan Hajnoczi static void iothread_get_poll_param(Object *obj, Visitor *v, 2060d9d86fbSStefan Hajnoczi const char *name, void *opaque, Error **errp) 2070d9d86fbSStefan Hajnoczi { 2080d9d86fbSStefan Hajnoczi IOThread *iothread = IOTHREAD(obj); 2095e5db499SStefan Hajnoczi PollParamInfo *info = opaque; 2105e5db499SStefan Hajnoczi int64_t *field = (void *)iothread + info->offset; 2110d9d86fbSStefan Hajnoczi 2125e5db499SStefan Hajnoczi visit_type_int64(v, name, field, errp); 2130d9d86fbSStefan Hajnoczi } 2140d9d86fbSStefan Hajnoczi 2155e5db499SStefan Hajnoczi static void iothread_set_poll_param(Object *obj, Visitor *v, 2160d9d86fbSStefan Hajnoczi const char *name, void *opaque, Error **errp) 2170d9d86fbSStefan Hajnoczi { 2180d9d86fbSStefan Hajnoczi IOThread *iothread = IOTHREAD(obj); 2195e5db499SStefan Hajnoczi PollParamInfo *info = opaque; 2205e5db499SStefan Hajnoczi int64_t *field = (void *)iothread + info->offset; 2210d9d86fbSStefan Hajnoczi Error *local_err = NULL; 2220d9d86fbSStefan Hajnoczi int64_t value; 2230d9d86fbSStefan Hajnoczi 2240d9d86fbSStefan Hajnoczi visit_type_int64(v, name, &value, &local_err); 2250d9d86fbSStefan Hajnoczi if (local_err) { 2260d9d86fbSStefan Hajnoczi goto out; 2270d9d86fbSStefan Hajnoczi } 2280d9d86fbSStefan Hajnoczi 2290d9d86fbSStefan Hajnoczi if (value < 0) { 2305e5db499SStefan Hajnoczi error_setg(&local_err, "%s value must be in range [0, %"PRId64"]", 2315e5db499SStefan Hajnoczi info->name, INT64_MAX); 2320d9d86fbSStefan Hajnoczi goto out; 2330d9d86fbSStefan Hajnoczi } 2340d9d86fbSStefan Hajnoczi 2355e5db499SStefan Hajnoczi *field = value; 2360d9d86fbSStefan Hajnoczi 2370d9d86fbSStefan Hajnoczi if (iothread->ctx) { 2385e5db499SStefan Hajnoczi aio_context_set_poll_params(iothread->ctx, 2395e5db499SStefan Hajnoczi iothread->poll_max_ns, 2405e5db499SStefan Hajnoczi iothread->poll_grow, 2415e5db499SStefan Hajnoczi iothread->poll_shrink, 2425e5db499SStefan Hajnoczi &local_err); 2430d9d86fbSStefan Hajnoczi } 2440d9d86fbSStefan Hajnoczi 2450d9d86fbSStefan Hajnoczi out: 2460d9d86fbSStefan Hajnoczi error_propagate(errp, local_err); 2470d9d86fbSStefan Hajnoczi } 2480d9d86fbSStefan Hajnoczi 249be8d8537SStefan Hajnoczi static void iothread_class_init(ObjectClass *klass, void *class_data) 250be8d8537SStefan Hajnoczi { 251be8d8537SStefan Hajnoczi UserCreatableClass *ucc = USER_CREATABLE_CLASS(klass); 252be8d8537SStefan Hajnoczi ucc->complete = iothread_complete; 2530d9d86fbSStefan Hajnoczi 2540d9d86fbSStefan Hajnoczi object_class_property_add(klass, "poll-max-ns", "int", 2555e5db499SStefan Hajnoczi iothread_get_poll_param, 2565e5db499SStefan Hajnoczi iothread_set_poll_param, 2575e5db499SStefan Hajnoczi NULL, &poll_max_ns_info, &error_abort); 2585e5db499SStefan Hajnoczi object_class_property_add(klass, "poll-grow", "int", 2595e5db499SStefan Hajnoczi iothread_get_poll_param, 2605e5db499SStefan Hajnoczi iothread_set_poll_param, 2615e5db499SStefan Hajnoczi NULL, &poll_grow_info, &error_abort); 2625e5db499SStefan Hajnoczi object_class_property_add(klass, "poll-shrink", "int", 2635e5db499SStefan Hajnoczi iothread_get_poll_param, 2645e5db499SStefan Hajnoczi iothread_set_poll_param, 2655e5db499SStefan Hajnoczi NULL, &poll_shrink_info, &error_abort); 266be8d8537SStefan Hajnoczi } 267be8d8537SStefan Hajnoczi 268be8d8537SStefan Hajnoczi static const TypeInfo iothread_info = { 269be8d8537SStefan Hajnoczi .name = TYPE_IOTHREAD, 270be8d8537SStefan Hajnoczi .parent = TYPE_OBJECT, 271be8d8537SStefan Hajnoczi .class_init = iothread_class_init, 272be8d8537SStefan Hajnoczi .instance_size = sizeof(IOThread), 273cdd7abfdSStefan Hajnoczi .instance_init = iothread_instance_init, 274be8d8537SStefan Hajnoczi .instance_finalize = iothread_instance_finalize, 275be8d8537SStefan Hajnoczi .interfaces = (InterfaceInfo[]) { 276be8d8537SStefan Hajnoczi {TYPE_USER_CREATABLE}, 277be8d8537SStefan Hajnoczi {} 278be8d8537SStefan Hajnoczi }, 279be8d8537SStefan Hajnoczi }; 280be8d8537SStefan Hajnoczi 281be8d8537SStefan Hajnoczi static void iothread_register_types(void) 282be8d8537SStefan Hajnoczi { 283be8d8537SStefan Hajnoczi type_register_static(&iothread_info); 284be8d8537SStefan Hajnoczi } 285be8d8537SStefan Hajnoczi 286be8d8537SStefan Hajnoczi type_init(iothread_register_types) 287be8d8537SStefan Hajnoczi 288be8d8537SStefan Hajnoczi char *iothread_get_id(IOThread *iothread) 289be8d8537SStefan Hajnoczi { 290be8d8537SStefan Hajnoczi return object_get_canonical_path_component(OBJECT(iothread)); 291be8d8537SStefan Hajnoczi } 292be8d8537SStefan Hajnoczi 293be8d8537SStefan Hajnoczi AioContext *iothread_get_aio_context(IOThread *iothread) 294be8d8537SStefan Hajnoczi { 295be8d8537SStefan Hajnoczi return iothread->ctx; 296be8d8537SStefan Hajnoczi } 297dc3dd0d2SStefan Hajnoczi 298dc3dd0d2SStefan Hajnoczi static int query_one_iothread(Object *object, void *opaque) 299dc3dd0d2SStefan Hajnoczi { 300dc3dd0d2SStefan Hajnoczi IOThreadInfoList ***prev = opaque; 301dc3dd0d2SStefan Hajnoczi IOThreadInfoList *elem; 302dc3dd0d2SStefan Hajnoczi IOThreadInfo *info; 303dc3dd0d2SStefan Hajnoczi IOThread *iothread; 304dc3dd0d2SStefan Hajnoczi 305dc3dd0d2SStefan Hajnoczi iothread = (IOThread *)object_dynamic_cast(object, TYPE_IOTHREAD); 306dc3dd0d2SStefan Hajnoczi if (!iothread) { 307dc3dd0d2SStefan Hajnoczi return 0; 308dc3dd0d2SStefan Hajnoczi } 309dc3dd0d2SStefan Hajnoczi 310dc3dd0d2SStefan Hajnoczi info = g_new0(IOThreadInfo, 1); 311dc3dd0d2SStefan Hajnoczi info->id = iothread_get_id(iothread); 312dc3dd0d2SStefan Hajnoczi info->thread_id = iothread->thread_id; 3135fc00480SPavel Hrdina info->poll_max_ns = iothread->poll_max_ns; 3145fc00480SPavel Hrdina info->poll_grow = iothread->poll_grow; 3155fc00480SPavel Hrdina info->poll_shrink = iothread->poll_shrink; 316dc3dd0d2SStefan Hajnoczi 317dc3dd0d2SStefan Hajnoczi elem = g_new0(IOThreadInfoList, 1); 318dc3dd0d2SStefan Hajnoczi elem->value = info; 319dc3dd0d2SStefan Hajnoczi elem->next = NULL; 320dc3dd0d2SStefan Hajnoczi 321dc3dd0d2SStefan Hajnoczi **prev = elem; 322dc3dd0d2SStefan Hajnoczi *prev = &elem->next; 323dc3dd0d2SStefan Hajnoczi return 0; 324dc3dd0d2SStefan Hajnoczi } 325dc3dd0d2SStefan Hajnoczi 326dc3dd0d2SStefan Hajnoczi IOThreadInfoList *qmp_query_iothreads(Error **errp) 327dc3dd0d2SStefan Hajnoczi { 328dc3dd0d2SStefan Hajnoczi IOThreadInfoList *head = NULL; 329dc3dd0d2SStefan Hajnoczi IOThreadInfoList **prev = &head; 330bc2256c4SDaniel P. Berrange Object *container = object_get_objects_root(); 331dc3dd0d2SStefan Hajnoczi 332dc3dd0d2SStefan Hajnoczi object_child_foreach(container, query_one_iothread, &prev); 333dc3dd0d2SStefan Hajnoczi return head; 334dc3dd0d2SStefan Hajnoczi } 335dce8921bSFam Zheng 336329163cbSWang Yong static gpointer iothread_g_main_context_init(gpointer opaque) 337329163cbSWang Yong { 338329163cbSWang Yong AioContext *ctx; 339329163cbSWang Yong IOThread *iothread = opaque; 340329163cbSWang Yong GSource *source; 341329163cbSWang Yong 342329163cbSWang Yong iothread->worker_context = g_main_context_new(); 343329163cbSWang Yong 344329163cbSWang Yong ctx = iothread_get_aio_context(iothread); 345329163cbSWang Yong source = aio_get_g_source(ctx); 346329163cbSWang Yong g_source_attach(source, iothread->worker_context); 347329163cbSWang Yong g_source_unref(source); 348329163cbSWang Yong 349329163cbSWang Yong aio_notify(iothread->ctx); 350329163cbSWang Yong return NULL; 351329163cbSWang Yong } 352329163cbSWang Yong 353329163cbSWang Yong GMainContext *iothread_get_g_main_context(IOThread *iothread) 354329163cbSWang Yong { 355329163cbSWang Yong g_once(&iothread->once, iothread_g_main_context_init, iothread); 356329163cbSWang Yong 357329163cbSWang Yong return iothread->worker_context; 358329163cbSWang Yong } 3590173e21bSPeter Xu 3600173e21bSPeter Xu IOThread *iothread_create(const char *id, Error **errp) 3610173e21bSPeter Xu { 3620173e21bSPeter Xu Object *obj; 3630173e21bSPeter Xu 3640173e21bSPeter Xu obj = object_new_with_props(TYPE_IOTHREAD, 3650173e21bSPeter Xu object_get_internal_root(), 3660173e21bSPeter Xu id, errp, NULL); 3670173e21bSPeter Xu 3680173e21bSPeter Xu return IOTHREAD(obj); 3690173e21bSPeter Xu } 3700173e21bSPeter Xu 3710173e21bSPeter Xu void iothread_destroy(IOThread *iothread) 3720173e21bSPeter Xu { 3730173e21bSPeter Xu object_unparent(OBJECT(iothread)); 3740173e21bSPeter Xu } 375fbcc6923SStefan Hajnoczi 376fbcc6923SStefan Hajnoczi /* Lookup IOThread by its id. Only finds user-created objects, not internal 377fbcc6923SStefan Hajnoczi * iothread_create() objects. */ 378fbcc6923SStefan Hajnoczi IOThread *iothread_by_id(const char *id) 379fbcc6923SStefan Hajnoczi { 380fbcc6923SStefan Hajnoczi return IOTHREAD(object_resolve_path_type(id, TYPE_IOTHREAD, NULL)); 381fbcc6923SStefan Hajnoczi } 382