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 34*90c558beSPeter 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 40*90c558beSPeter Xu #else 41*90c558beSPeter Xu #define IOTHREAD_POLL_MAX_NS_DEFAULT 0ULL 42*90c558beSPeter 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 qemu_mutex_lock(&iothread->init_done_lock); 5988eb7c29SStefan Hajnoczi iothread->thread_id = qemu_get_thread_id(); 6088eb7c29SStefan Hajnoczi qemu_cond_signal(&iothread->init_done_cond); 6188eb7c29SStefan Hajnoczi qemu_mutex_unlock(&iothread->init_done_lock); 6288eb7c29SStefan Hajnoczi 632362a28eSStefan Hajnoczi while (iothread->running) { 6465c1b5b6SPaolo Bonzini aio_poll(iothread->ctx, true); 65329163cbSWang Yong 66329163cbSWang Yong if (atomic_read(&iothread->worker_context)) { 67329163cbSWang Yong GMainLoop *loop; 68329163cbSWang Yong 69329163cbSWang Yong g_main_context_push_thread_default(iothread->worker_context); 70329163cbSWang Yong iothread->main_loop = 71329163cbSWang Yong g_main_loop_new(iothread->worker_context, TRUE); 72329163cbSWang Yong loop = iothread->main_loop; 73329163cbSWang Yong 74329163cbSWang Yong g_main_loop_run(iothread->main_loop); 75329163cbSWang Yong iothread->main_loop = NULL; 76329163cbSWang Yong g_main_loop_unref(loop); 77329163cbSWang Yong 78329163cbSWang Yong g_main_context_pop_thread_default(iothread->worker_context); 79329163cbSWang Yong } 80be8d8537SStefan Hajnoczi } 81ab28bd23SPaolo Bonzini 82ab28bd23SPaolo Bonzini rcu_unregister_thread(); 83be8d8537SStefan Hajnoczi return NULL; 84be8d8537SStefan Hajnoczi } 85be8d8537SStefan Hajnoczi 862362a28eSStefan Hajnoczi /* Runs in iothread_run() thread */ 872362a28eSStefan Hajnoczi static void iothread_stop_bh(void *opaque) 882362a28eSStefan Hajnoczi { 892362a28eSStefan Hajnoczi IOThread *iothread = opaque; 902362a28eSStefan Hajnoczi 912362a28eSStefan Hajnoczi iothread->running = false; /* stop iothread_run() */ 922362a28eSStefan Hajnoczi 932362a28eSStefan Hajnoczi if (iothread->main_loop) { 942362a28eSStefan Hajnoczi g_main_loop_quit(iothread->main_loop); 952362a28eSStefan Hajnoczi } 962362a28eSStefan Hajnoczi } 972362a28eSStefan Hajnoczi 9882d90705SPeter Xu void iothread_stop(IOThread *iothread) 99be8d8537SStefan Hajnoczi { 10082d90705SPeter Xu if (!iothread->ctx || iothread->stopping) { 10182d90705SPeter Xu return; 1022f78e491SChrysostomos Nanakos } 103be8d8537SStefan Hajnoczi iothread->stopping = true; 1042362a28eSStefan Hajnoczi aio_bh_schedule_oneshot(iothread->ctx, iothread_stop_bh, iothread); 105be8d8537SStefan Hajnoczi qemu_thread_join(&iothread->thread); 10682d90705SPeter Xu } 10782d90705SPeter Xu 108cdd7abfdSStefan Hajnoczi static void iothread_instance_init(Object *obj) 109cdd7abfdSStefan Hajnoczi { 110cdd7abfdSStefan Hajnoczi IOThread *iothread = IOTHREAD(obj); 111cdd7abfdSStefan Hajnoczi 112cdd7abfdSStefan Hajnoczi iothread->poll_max_ns = IOTHREAD_POLL_MAX_NS_DEFAULT; 113cdd7abfdSStefan Hajnoczi } 114cdd7abfdSStefan Hajnoczi 115dce8921bSFam Zheng static void iothread_instance_finalize(Object *obj) 116dce8921bSFam Zheng { 117dce8921bSFam Zheng IOThread *iothread = IOTHREAD(obj); 118dce8921bSFam Zheng 11982d90705SPeter Xu iothread_stop(iothread); 1205b3ac23fSPeter Xu if (iothread->worker_context) { 1215b3ac23fSPeter Xu g_main_context_unref(iothread->worker_context); 1225b3ac23fSPeter Xu iothread->worker_context = NULL; 1235b3ac23fSPeter Xu } 12488eb7c29SStefan Hajnoczi qemu_cond_destroy(&iothread->init_done_cond); 12588eb7c29SStefan Hajnoczi qemu_mutex_destroy(&iothread->init_done_lock); 126eb7b5c35SLin Ma if (!iothread->ctx) { 127eb7b5c35SLin Ma return; 128eb7b5c35SLin Ma } 129be8d8537SStefan Hajnoczi aio_context_unref(iothread->ctx); 130be8d8537SStefan Hajnoczi } 131be8d8537SStefan Hajnoczi 132be8d8537SStefan Hajnoczi static void iothread_complete(UserCreatable *obj, Error **errp) 133be8d8537SStefan Hajnoczi { 1342f78e491SChrysostomos Nanakos Error *local_error = NULL; 135be8d8537SStefan Hajnoczi IOThread *iothread = IOTHREAD(obj); 136d21e8776SPaolo Bonzini char *name, *thread_name; 137be8d8537SStefan Hajnoczi 138be8d8537SStefan Hajnoczi iothread->stopping = false; 1392362a28eSStefan Hajnoczi iothread->running = true; 14088eb7c29SStefan Hajnoczi iothread->thread_id = -1; 1412f78e491SChrysostomos Nanakos iothread->ctx = aio_context_new(&local_error); 1422f78e491SChrysostomos Nanakos if (!iothread->ctx) { 1432f78e491SChrysostomos Nanakos error_propagate(errp, local_error); 1442f78e491SChrysostomos Nanakos return; 1452f78e491SChrysostomos Nanakos } 14688eb7c29SStefan Hajnoczi 1475e5db499SStefan Hajnoczi aio_context_set_poll_params(iothread->ctx, 1485e5db499SStefan Hajnoczi iothread->poll_max_ns, 1495e5db499SStefan Hajnoczi iothread->poll_grow, 1505e5db499SStefan Hajnoczi iothread->poll_shrink, 1510d9d86fbSStefan Hajnoczi &local_error); 1520d9d86fbSStefan Hajnoczi if (local_error) { 1530d9d86fbSStefan Hajnoczi error_propagate(errp, local_error); 1540d9d86fbSStefan Hajnoczi aio_context_unref(iothread->ctx); 1550d9d86fbSStefan Hajnoczi iothread->ctx = NULL; 1560d9d86fbSStefan Hajnoczi return; 1570d9d86fbSStefan Hajnoczi } 1580d9d86fbSStefan Hajnoczi 15988eb7c29SStefan Hajnoczi qemu_mutex_init(&iothread->init_done_lock); 16088eb7c29SStefan Hajnoczi qemu_cond_init(&iothread->init_done_cond); 161329163cbSWang Yong iothread->once = (GOnce) G_ONCE_INIT; 162be8d8537SStefan Hajnoczi 163be8d8537SStefan Hajnoczi /* This assumes we are called from a thread with useful CPU affinity for us 164be8d8537SStefan Hajnoczi * to inherit. 165be8d8537SStefan Hajnoczi */ 166d21e8776SPaolo Bonzini name = object_get_canonical_path_component(OBJECT(obj)); 167d21e8776SPaolo Bonzini thread_name = g_strdup_printf("IO %s", name); 168d21e8776SPaolo Bonzini qemu_thread_create(&iothread->thread, thread_name, iothread_run, 169be8d8537SStefan Hajnoczi iothread, QEMU_THREAD_JOINABLE); 170d21e8776SPaolo Bonzini g_free(thread_name); 171d21e8776SPaolo Bonzini g_free(name); 17288eb7c29SStefan Hajnoczi 17388eb7c29SStefan Hajnoczi /* Wait for initialization to complete */ 17488eb7c29SStefan Hajnoczi qemu_mutex_lock(&iothread->init_done_lock); 17588eb7c29SStefan Hajnoczi while (iothread->thread_id == -1) { 17688eb7c29SStefan Hajnoczi qemu_cond_wait(&iothread->init_done_cond, 17788eb7c29SStefan Hajnoczi &iothread->init_done_lock); 17888eb7c29SStefan Hajnoczi } 17988eb7c29SStefan Hajnoczi qemu_mutex_unlock(&iothread->init_done_lock); 180be8d8537SStefan Hajnoczi } 181be8d8537SStefan Hajnoczi 1825e5db499SStefan Hajnoczi typedef struct { 1835e5db499SStefan Hajnoczi const char *name; 1845e5db499SStefan Hajnoczi ptrdiff_t offset; /* field's byte offset in IOThread struct */ 1855e5db499SStefan Hajnoczi } PollParamInfo; 1865e5db499SStefan Hajnoczi 1875e5db499SStefan Hajnoczi static PollParamInfo poll_max_ns_info = { 1885e5db499SStefan Hajnoczi "poll-max-ns", offsetof(IOThread, poll_max_ns), 1895e5db499SStefan Hajnoczi }; 1905e5db499SStefan Hajnoczi static PollParamInfo poll_grow_info = { 1915e5db499SStefan Hajnoczi "poll-grow", offsetof(IOThread, poll_grow), 1925e5db499SStefan Hajnoczi }; 1935e5db499SStefan Hajnoczi static PollParamInfo poll_shrink_info = { 1945e5db499SStefan Hajnoczi "poll-shrink", offsetof(IOThread, poll_shrink), 1955e5db499SStefan Hajnoczi }; 1965e5db499SStefan Hajnoczi 1975e5db499SStefan Hajnoczi static void iothread_get_poll_param(Object *obj, Visitor *v, 1980d9d86fbSStefan Hajnoczi const char *name, void *opaque, Error **errp) 1990d9d86fbSStefan Hajnoczi { 2000d9d86fbSStefan Hajnoczi IOThread *iothread = IOTHREAD(obj); 2015e5db499SStefan Hajnoczi PollParamInfo *info = opaque; 2025e5db499SStefan Hajnoczi int64_t *field = (void *)iothread + info->offset; 2030d9d86fbSStefan Hajnoczi 2045e5db499SStefan Hajnoczi visit_type_int64(v, name, field, errp); 2050d9d86fbSStefan Hajnoczi } 2060d9d86fbSStefan Hajnoczi 2075e5db499SStefan Hajnoczi static void iothread_set_poll_param(Object *obj, Visitor *v, 2080d9d86fbSStefan Hajnoczi const char *name, void *opaque, Error **errp) 2090d9d86fbSStefan Hajnoczi { 2100d9d86fbSStefan Hajnoczi IOThread *iothread = IOTHREAD(obj); 2115e5db499SStefan Hajnoczi PollParamInfo *info = opaque; 2125e5db499SStefan Hajnoczi int64_t *field = (void *)iothread + info->offset; 2130d9d86fbSStefan Hajnoczi Error *local_err = NULL; 2140d9d86fbSStefan Hajnoczi int64_t value; 2150d9d86fbSStefan Hajnoczi 2160d9d86fbSStefan Hajnoczi visit_type_int64(v, name, &value, &local_err); 2170d9d86fbSStefan Hajnoczi if (local_err) { 2180d9d86fbSStefan Hajnoczi goto out; 2190d9d86fbSStefan Hajnoczi } 2200d9d86fbSStefan Hajnoczi 2210d9d86fbSStefan Hajnoczi if (value < 0) { 2225e5db499SStefan Hajnoczi error_setg(&local_err, "%s value must be in range [0, %"PRId64"]", 2235e5db499SStefan Hajnoczi info->name, INT64_MAX); 2240d9d86fbSStefan Hajnoczi goto out; 2250d9d86fbSStefan Hajnoczi } 2260d9d86fbSStefan Hajnoczi 2275e5db499SStefan Hajnoczi *field = value; 2280d9d86fbSStefan Hajnoczi 2290d9d86fbSStefan Hajnoczi if (iothread->ctx) { 2305e5db499SStefan Hajnoczi aio_context_set_poll_params(iothread->ctx, 2315e5db499SStefan Hajnoczi iothread->poll_max_ns, 2325e5db499SStefan Hajnoczi iothread->poll_grow, 2335e5db499SStefan Hajnoczi iothread->poll_shrink, 2345e5db499SStefan Hajnoczi &local_err); 2350d9d86fbSStefan Hajnoczi } 2360d9d86fbSStefan Hajnoczi 2370d9d86fbSStefan Hajnoczi out: 2380d9d86fbSStefan Hajnoczi error_propagate(errp, local_err); 2390d9d86fbSStefan Hajnoczi } 2400d9d86fbSStefan Hajnoczi 241be8d8537SStefan Hajnoczi static void iothread_class_init(ObjectClass *klass, void *class_data) 242be8d8537SStefan Hajnoczi { 243be8d8537SStefan Hajnoczi UserCreatableClass *ucc = USER_CREATABLE_CLASS(klass); 244be8d8537SStefan Hajnoczi ucc->complete = iothread_complete; 2450d9d86fbSStefan Hajnoczi 2460d9d86fbSStefan Hajnoczi object_class_property_add(klass, "poll-max-ns", "int", 2475e5db499SStefan Hajnoczi iothread_get_poll_param, 2485e5db499SStefan Hajnoczi iothread_set_poll_param, 2495e5db499SStefan Hajnoczi NULL, &poll_max_ns_info, &error_abort); 2505e5db499SStefan Hajnoczi object_class_property_add(klass, "poll-grow", "int", 2515e5db499SStefan Hajnoczi iothread_get_poll_param, 2525e5db499SStefan Hajnoczi iothread_set_poll_param, 2535e5db499SStefan Hajnoczi NULL, &poll_grow_info, &error_abort); 2545e5db499SStefan Hajnoczi object_class_property_add(klass, "poll-shrink", "int", 2555e5db499SStefan Hajnoczi iothread_get_poll_param, 2565e5db499SStefan Hajnoczi iothread_set_poll_param, 2575e5db499SStefan Hajnoczi NULL, &poll_shrink_info, &error_abort); 258be8d8537SStefan Hajnoczi } 259be8d8537SStefan Hajnoczi 260be8d8537SStefan Hajnoczi static const TypeInfo iothread_info = { 261be8d8537SStefan Hajnoczi .name = TYPE_IOTHREAD, 262be8d8537SStefan Hajnoczi .parent = TYPE_OBJECT, 263be8d8537SStefan Hajnoczi .class_init = iothread_class_init, 264be8d8537SStefan Hajnoczi .instance_size = sizeof(IOThread), 265cdd7abfdSStefan Hajnoczi .instance_init = iothread_instance_init, 266be8d8537SStefan Hajnoczi .instance_finalize = iothread_instance_finalize, 267be8d8537SStefan Hajnoczi .interfaces = (InterfaceInfo[]) { 268be8d8537SStefan Hajnoczi {TYPE_USER_CREATABLE}, 269be8d8537SStefan Hajnoczi {} 270be8d8537SStefan Hajnoczi }, 271be8d8537SStefan Hajnoczi }; 272be8d8537SStefan Hajnoczi 273be8d8537SStefan Hajnoczi static void iothread_register_types(void) 274be8d8537SStefan Hajnoczi { 275be8d8537SStefan Hajnoczi type_register_static(&iothread_info); 276be8d8537SStefan Hajnoczi } 277be8d8537SStefan Hajnoczi 278be8d8537SStefan Hajnoczi type_init(iothread_register_types) 279be8d8537SStefan Hajnoczi 280be8d8537SStefan Hajnoczi char *iothread_get_id(IOThread *iothread) 281be8d8537SStefan Hajnoczi { 282be8d8537SStefan Hajnoczi return object_get_canonical_path_component(OBJECT(iothread)); 283be8d8537SStefan Hajnoczi } 284be8d8537SStefan Hajnoczi 285be8d8537SStefan Hajnoczi AioContext *iothread_get_aio_context(IOThread *iothread) 286be8d8537SStefan Hajnoczi { 287be8d8537SStefan Hajnoczi return iothread->ctx; 288be8d8537SStefan Hajnoczi } 289dc3dd0d2SStefan Hajnoczi 290dc3dd0d2SStefan Hajnoczi static int query_one_iothread(Object *object, void *opaque) 291dc3dd0d2SStefan Hajnoczi { 292dc3dd0d2SStefan Hajnoczi IOThreadInfoList ***prev = opaque; 293dc3dd0d2SStefan Hajnoczi IOThreadInfoList *elem; 294dc3dd0d2SStefan Hajnoczi IOThreadInfo *info; 295dc3dd0d2SStefan Hajnoczi IOThread *iothread; 296dc3dd0d2SStefan Hajnoczi 297dc3dd0d2SStefan Hajnoczi iothread = (IOThread *)object_dynamic_cast(object, TYPE_IOTHREAD); 298dc3dd0d2SStefan Hajnoczi if (!iothread) { 299dc3dd0d2SStefan Hajnoczi return 0; 300dc3dd0d2SStefan Hajnoczi } 301dc3dd0d2SStefan Hajnoczi 302dc3dd0d2SStefan Hajnoczi info = g_new0(IOThreadInfo, 1); 303dc3dd0d2SStefan Hajnoczi info->id = iothread_get_id(iothread); 304dc3dd0d2SStefan Hajnoczi info->thread_id = iothread->thread_id; 3055fc00480SPavel Hrdina info->poll_max_ns = iothread->poll_max_ns; 3065fc00480SPavel Hrdina info->poll_grow = iothread->poll_grow; 3075fc00480SPavel Hrdina info->poll_shrink = iothread->poll_shrink; 308dc3dd0d2SStefan Hajnoczi 309dc3dd0d2SStefan Hajnoczi elem = g_new0(IOThreadInfoList, 1); 310dc3dd0d2SStefan Hajnoczi elem->value = info; 311dc3dd0d2SStefan Hajnoczi elem->next = NULL; 312dc3dd0d2SStefan Hajnoczi 313dc3dd0d2SStefan Hajnoczi **prev = elem; 314dc3dd0d2SStefan Hajnoczi *prev = &elem->next; 315dc3dd0d2SStefan Hajnoczi return 0; 316dc3dd0d2SStefan Hajnoczi } 317dc3dd0d2SStefan Hajnoczi 318dc3dd0d2SStefan Hajnoczi IOThreadInfoList *qmp_query_iothreads(Error **errp) 319dc3dd0d2SStefan Hajnoczi { 320dc3dd0d2SStefan Hajnoczi IOThreadInfoList *head = NULL; 321dc3dd0d2SStefan Hajnoczi IOThreadInfoList **prev = &head; 322bc2256c4SDaniel P. Berrange Object *container = object_get_objects_root(); 323dc3dd0d2SStefan Hajnoczi 324dc3dd0d2SStefan Hajnoczi object_child_foreach(container, query_one_iothread, &prev); 325dc3dd0d2SStefan Hajnoczi return head; 326dc3dd0d2SStefan Hajnoczi } 327dce8921bSFam Zheng 328329163cbSWang Yong static gpointer iothread_g_main_context_init(gpointer opaque) 329329163cbSWang Yong { 330329163cbSWang Yong AioContext *ctx; 331329163cbSWang Yong IOThread *iothread = opaque; 332329163cbSWang Yong GSource *source; 333329163cbSWang Yong 334329163cbSWang Yong iothread->worker_context = g_main_context_new(); 335329163cbSWang Yong 336329163cbSWang Yong ctx = iothread_get_aio_context(iothread); 337329163cbSWang Yong source = aio_get_g_source(ctx); 338329163cbSWang Yong g_source_attach(source, iothread->worker_context); 339329163cbSWang Yong g_source_unref(source); 340329163cbSWang Yong 341329163cbSWang Yong aio_notify(iothread->ctx); 342329163cbSWang Yong return NULL; 343329163cbSWang Yong } 344329163cbSWang Yong 345329163cbSWang Yong GMainContext *iothread_get_g_main_context(IOThread *iothread) 346329163cbSWang Yong { 347329163cbSWang Yong g_once(&iothread->once, iothread_g_main_context_init, iothread); 348329163cbSWang Yong 349329163cbSWang Yong return iothread->worker_context; 350329163cbSWang Yong } 3510173e21bSPeter Xu 3520173e21bSPeter Xu IOThread *iothread_create(const char *id, Error **errp) 3530173e21bSPeter Xu { 3540173e21bSPeter Xu Object *obj; 3550173e21bSPeter Xu 3560173e21bSPeter Xu obj = object_new_with_props(TYPE_IOTHREAD, 3570173e21bSPeter Xu object_get_internal_root(), 3580173e21bSPeter Xu id, errp, NULL); 3590173e21bSPeter Xu 3600173e21bSPeter Xu return IOTHREAD(obj); 3610173e21bSPeter Xu } 3620173e21bSPeter Xu 3630173e21bSPeter Xu void iothread_destroy(IOThread *iothread) 3640173e21bSPeter Xu { 3650173e21bSPeter Xu object_unparent(OBJECT(iothread)); 3660173e21bSPeter Xu } 367fbcc6923SStefan Hajnoczi 368fbcc6923SStefan Hajnoczi /* Lookup IOThread by its id. Only finds user-created objects, not internal 369fbcc6923SStefan Hajnoczi * iothread_create() objects. */ 370fbcc6923SStefan Hajnoczi IOThread *iothread_by_id(const char *id) 371fbcc6923SStefan Hajnoczi { 372fbcc6923SStefan Hajnoczi return IOTHREAD(object_resolve_path_type(id, TYPE_IOTHREAD, NULL)); 373fbcc6923SStefan Hajnoczi } 374