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 298110fa1dSEduardo Habkost DECLARE_CLASS_CHECKERS(IOThreadClass, IOTHREAD, 308110fa1dSEduardo Habkost TYPE_IOTHREAD) 31be8d8537SStefan Hajnoczi 3290c558beSPeter Xu #ifdef CONFIG_POSIX 33cdd7abfdSStefan Hajnoczi /* Benchmark results from 2016 on NVMe SSD drives show max polling times around 34cdd7abfdSStefan Hajnoczi * 16-32 microseconds yield IOPS improvements for both iodepth=1 and iodepth=32 35cdd7abfdSStefan Hajnoczi * workloads. 36cdd7abfdSStefan Hajnoczi */ 37cdd7abfdSStefan Hajnoczi #define IOTHREAD_POLL_MAX_NS_DEFAULT 32768ULL 3890c558beSPeter Xu #else 3990c558beSPeter Xu #define IOTHREAD_POLL_MAX_NS_DEFAULT 0ULL 4090c558beSPeter Xu #endif 41cdd7abfdSStefan Hajnoczi 42e4370165SPaolo Bonzini static __thread IOThread *my_iothread; 43e4370165SPaolo Bonzini 44e4370165SPaolo Bonzini AioContext *qemu_get_current_aio_context(void) 45e4370165SPaolo Bonzini { 46e4370165SPaolo Bonzini return my_iothread ? my_iothread->ctx : qemu_get_aio_context(); 47e4370165SPaolo Bonzini } 48e4370165SPaolo Bonzini 49be8d8537SStefan Hajnoczi static void *iothread_run(void *opaque) 50be8d8537SStefan Hajnoczi { 51be8d8537SStefan Hajnoczi IOThread *iothread = opaque; 52be8d8537SStefan Hajnoczi 53ab28bd23SPaolo Bonzini rcu_register_thread(); 54b60ec76aSPeter Xu /* 55b60ec76aSPeter Xu * g_main_context_push_thread_default() must be called before anything 56b60ec76aSPeter Xu * in this new thread uses glib. 57b60ec76aSPeter Xu */ 58b60ec76aSPeter Xu g_main_context_push_thread_default(iothread->worker_context); 59e4370165SPaolo Bonzini my_iothread = iothread; 6088eb7c29SStefan Hajnoczi iothread->thread_id = qemu_get_thread_id(); 6121c4d15bSPeter Xu qemu_sem_post(&iothread->init_done_sem); 6288eb7c29SStefan Hajnoczi 632362a28eSStefan Hajnoczi while (iothread->running) { 646ca20620SPeter Xu /* 656ca20620SPeter Xu * Note: from functional-wise the g_main_loop_run() below can 666ca20620SPeter Xu * already cover the aio_poll() events, but we can't run the 676ca20620SPeter Xu * main loop unconditionally because explicit aio_poll() here 686ca20620SPeter Xu * is faster than g_main_loop_run() when we do not need the 696ca20620SPeter Xu * gcontext at all (e.g., pure block layer iothreads). In 706ca20620SPeter Xu * other words, when we want to run the gcontext with the 716ca20620SPeter Xu * iothread we need to pay some performance for functionality. 726ca20620SPeter Xu */ 7365c1b5b6SPaolo Bonzini aio_poll(iothread->ctx, true); 74329163cbSWang Yong 756c95363dSPeter Xu /* 766c95363dSPeter Xu * We must check the running state again in case it was 776c95363dSPeter Xu * changed in previous aio_poll() 786c95363dSPeter Xu */ 79*d73415a3SStefan Hajnoczi if (iothread->running && qatomic_read(&iothread->run_gcontext)) { 80329163cbSWang Yong g_main_loop_run(iothread->main_loop); 81329163cbSWang Yong } 82be8d8537SStefan Hajnoczi } 83ab28bd23SPaolo Bonzini 84b60ec76aSPeter Xu g_main_context_pop_thread_default(iothread->worker_context); 85ab28bd23SPaolo Bonzini rcu_unregister_thread(); 86be8d8537SStefan Hajnoczi return NULL; 87be8d8537SStefan Hajnoczi } 88be8d8537SStefan Hajnoczi 892362a28eSStefan Hajnoczi /* Runs in iothread_run() thread */ 902362a28eSStefan Hajnoczi static void iothread_stop_bh(void *opaque) 912362a28eSStefan Hajnoczi { 922362a28eSStefan Hajnoczi IOThread *iothread = opaque; 932362a28eSStefan Hajnoczi 942362a28eSStefan Hajnoczi iothread->running = false; /* stop iothread_run() */ 952362a28eSStefan Hajnoczi 962362a28eSStefan Hajnoczi if (iothread->main_loop) { 972362a28eSStefan Hajnoczi g_main_loop_quit(iothread->main_loop); 982362a28eSStefan Hajnoczi } 992362a28eSStefan Hajnoczi } 1002362a28eSStefan Hajnoczi 10182d90705SPeter Xu void iothread_stop(IOThread *iothread) 102be8d8537SStefan Hajnoczi { 10382d90705SPeter Xu if (!iothread->ctx || iothread->stopping) { 10482d90705SPeter Xu return; 1052f78e491SChrysostomos Nanakos } 106be8d8537SStefan Hajnoczi iothread->stopping = true; 1072362a28eSStefan Hajnoczi aio_bh_schedule_oneshot(iothread->ctx, iothread_stop_bh, iothread); 108be8d8537SStefan Hajnoczi qemu_thread_join(&iothread->thread); 10982d90705SPeter Xu } 11082d90705SPeter Xu 111cdd7abfdSStefan Hajnoczi static void iothread_instance_init(Object *obj) 112cdd7abfdSStefan Hajnoczi { 113cdd7abfdSStefan Hajnoczi IOThread *iothread = IOTHREAD(obj); 114cdd7abfdSStefan Hajnoczi 115cdd7abfdSStefan Hajnoczi iothread->poll_max_ns = IOTHREAD_POLL_MAX_NS_DEFAULT; 11614a2d118SMarc-André Lureau iothread->thread_id = -1; 11721c4d15bSPeter Xu qemu_sem_init(&iothread->init_done_sem, 0); 118b506e0f1SPeter Xu /* By default, we don't run gcontext */ 119*d73415a3SStefan Hajnoczi qatomic_set(&iothread->run_gcontext, 0); 120cdd7abfdSStefan Hajnoczi } 121cdd7abfdSStefan Hajnoczi 122dce8921bSFam Zheng static void iothread_instance_finalize(Object *obj) 123dce8921bSFam Zheng { 124dce8921bSFam Zheng IOThread *iothread = IOTHREAD(obj); 125dce8921bSFam Zheng 12682d90705SPeter Xu iothread_stop(iothread); 12714a2d118SMarc-André Lureau 12815544349SPeter Xu /* 12915544349SPeter Xu * Before glib2 2.33.10, there is a glib2 bug that GSource context 13015544349SPeter Xu * pointer may not be cleared even if the context has already been 13115544349SPeter Xu * destroyed (while it should). Here let's free the AIO context 13215544349SPeter Xu * earlier to bypass that glib bug. 13315544349SPeter Xu * 13415544349SPeter Xu * We can remove this comment after the minimum supported glib2 13515544349SPeter Xu * version boosts to 2.33.10. Before that, let's free the 13615544349SPeter Xu * GSources first before destroying any GMainContext. 13715544349SPeter Xu */ 13815544349SPeter Xu if (iothread->ctx) { 13915544349SPeter Xu aio_context_unref(iothread->ctx); 14015544349SPeter Xu iothread->ctx = NULL; 14115544349SPeter Xu } 1425b3ac23fSPeter Xu if (iothread->worker_context) { 1435b3ac23fSPeter Xu g_main_context_unref(iothread->worker_context); 1445b3ac23fSPeter Xu iothread->worker_context = NULL; 1450bd2d233SPeter Xu g_main_loop_unref(iothread->main_loop); 1460bd2d233SPeter Xu iothread->main_loop = NULL; 1475b3ac23fSPeter Xu } 14821c4d15bSPeter Xu qemu_sem_destroy(&iothread->init_done_sem); 149be8d8537SStefan Hajnoczi } 150be8d8537SStefan Hajnoczi 151b506e0f1SPeter Xu static void iothread_init_gcontext(IOThread *iothread) 152b506e0f1SPeter Xu { 153b506e0f1SPeter Xu GSource *source; 154b506e0f1SPeter Xu 155b506e0f1SPeter Xu iothread->worker_context = g_main_context_new(); 156b506e0f1SPeter Xu source = aio_get_g_source(iothread_get_aio_context(iothread)); 157b506e0f1SPeter Xu g_source_attach(source, iothread->worker_context); 158b506e0f1SPeter Xu g_source_unref(source); 1590bd2d233SPeter Xu iothread->main_loop = g_main_loop_new(iothread->worker_context, TRUE); 160b506e0f1SPeter Xu } 161b506e0f1SPeter Xu 162be8d8537SStefan Hajnoczi static void iothread_complete(UserCreatable *obj, Error **errp) 163be8d8537SStefan Hajnoczi { 1642f78e491SChrysostomos Nanakos Error *local_error = NULL; 165be8d8537SStefan Hajnoczi IOThread *iothread = IOTHREAD(obj); 1667a309cc9SMarkus Armbruster char *thread_name; 167be8d8537SStefan Hajnoczi 168be8d8537SStefan Hajnoczi iothread->stopping = false; 1692362a28eSStefan Hajnoczi iothread->running = true; 170668f62ecSMarkus Armbruster iothread->ctx = aio_context_new(errp); 1712f78e491SChrysostomos Nanakos if (!iothread->ctx) { 1722f78e491SChrysostomos Nanakos return; 1732f78e491SChrysostomos Nanakos } 17488eb7c29SStefan Hajnoczi 175b506e0f1SPeter Xu /* 176b506e0f1SPeter Xu * Init one GMainContext for the iothread unconditionally, even if 177b506e0f1SPeter Xu * it's not used 178b506e0f1SPeter Xu */ 179b506e0f1SPeter Xu iothread_init_gcontext(iothread); 180b506e0f1SPeter Xu 1815e5db499SStefan Hajnoczi aio_context_set_poll_params(iothread->ctx, 1825e5db499SStefan Hajnoczi iothread->poll_max_ns, 1835e5db499SStefan Hajnoczi iothread->poll_grow, 1845e5db499SStefan Hajnoczi iothread->poll_shrink, 1850d9d86fbSStefan Hajnoczi &local_error); 1860d9d86fbSStefan Hajnoczi if (local_error) { 1870d9d86fbSStefan Hajnoczi error_propagate(errp, local_error); 1880d9d86fbSStefan Hajnoczi aio_context_unref(iothread->ctx); 1890d9d86fbSStefan Hajnoczi iothread->ctx = NULL; 1900d9d86fbSStefan Hajnoczi return; 1910d9d86fbSStefan Hajnoczi } 1920d9d86fbSStefan Hajnoczi 193be8d8537SStefan Hajnoczi /* This assumes we are called from a thread with useful CPU affinity for us 194be8d8537SStefan Hajnoczi * to inherit. 195be8d8537SStefan Hajnoczi */ 1967a309cc9SMarkus Armbruster thread_name = g_strdup_printf("IO %s", 1977a309cc9SMarkus Armbruster object_get_canonical_path_component(OBJECT(obj))); 198d21e8776SPaolo Bonzini qemu_thread_create(&iothread->thread, thread_name, iothread_run, 199be8d8537SStefan Hajnoczi iothread, QEMU_THREAD_JOINABLE); 200d21e8776SPaolo Bonzini g_free(thread_name); 20188eb7c29SStefan Hajnoczi 20288eb7c29SStefan Hajnoczi /* Wait for initialization to complete */ 20388eb7c29SStefan Hajnoczi while (iothread->thread_id == -1) { 20421c4d15bSPeter Xu qemu_sem_wait(&iothread->init_done_sem); 20588eb7c29SStefan Hajnoczi } 206be8d8537SStefan Hajnoczi } 207be8d8537SStefan Hajnoczi 2085e5db499SStefan Hajnoczi typedef struct { 2095e5db499SStefan Hajnoczi const char *name; 2105e5db499SStefan Hajnoczi ptrdiff_t offset; /* field's byte offset in IOThread struct */ 2115e5db499SStefan Hajnoczi } PollParamInfo; 2125e5db499SStefan Hajnoczi 2135e5db499SStefan Hajnoczi static PollParamInfo poll_max_ns_info = { 2145e5db499SStefan Hajnoczi "poll-max-ns", offsetof(IOThread, poll_max_ns), 2155e5db499SStefan Hajnoczi }; 2165e5db499SStefan Hajnoczi static PollParamInfo poll_grow_info = { 2175e5db499SStefan Hajnoczi "poll-grow", offsetof(IOThread, poll_grow), 2185e5db499SStefan Hajnoczi }; 2195e5db499SStefan Hajnoczi static PollParamInfo poll_shrink_info = { 2205e5db499SStefan Hajnoczi "poll-shrink", offsetof(IOThread, poll_shrink), 2215e5db499SStefan Hajnoczi }; 2225e5db499SStefan Hajnoczi 2235e5db499SStefan Hajnoczi static void iothread_get_poll_param(Object *obj, Visitor *v, 2240d9d86fbSStefan Hajnoczi const char *name, void *opaque, Error **errp) 2250d9d86fbSStefan Hajnoczi { 2260d9d86fbSStefan Hajnoczi IOThread *iothread = IOTHREAD(obj); 2275e5db499SStefan Hajnoczi PollParamInfo *info = opaque; 2285e5db499SStefan Hajnoczi int64_t *field = (void *)iothread + info->offset; 2290d9d86fbSStefan Hajnoczi 2305e5db499SStefan Hajnoczi visit_type_int64(v, name, field, errp); 2310d9d86fbSStefan Hajnoczi } 2320d9d86fbSStefan Hajnoczi 2335e5db499SStefan Hajnoczi static void iothread_set_poll_param(Object *obj, Visitor *v, 2340d9d86fbSStefan Hajnoczi const char *name, void *opaque, Error **errp) 2350d9d86fbSStefan Hajnoczi { 2360d9d86fbSStefan Hajnoczi IOThread *iothread = IOTHREAD(obj); 2375e5db499SStefan Hajnoczi PollParamInfo *info = opaque; 2385e5db499SStefan Hajnoczi int64_t *field = (void *)iothread + info->offset; 2390d9d86fbSStefan Hajnoczi int64_t value; 2400d9d86fbSStefan Hajnoczi 241668f62ecSMarkus Armbruster if (!visit_type_int64(v, name, &value, errp)) { 242dcfe4805SMarkus Armbruster return; 2430d9d86fbSStefan Hajnoczi } 2440d9d86fbSStefan Hajnoczi 2450d9d86fbSStefan Hajnoczi if (value < 0) { 246dcfe4805SMarkus Armbruster error_setg(errp, "%s value must be in range [0, %" PRId64 "]", 2475e5db499SStefan Hajnoczi info->name, INT64_MAX); 248dcfe4805SMarkus Armbruster return; 2490d9d86fbSStefan Hajnoczi } 2500d9d86fbSStefan Hajnoczi 2515e5db499SStefan Hajnoczi *field = value; 2520d9d86fbSStefan Hajnoczi 2530d9d86fbSStefan Hajnoczi if (iothread->ctx) { 2545e5db499SStefan Hajnoczi aio_context_set_poll_params(iothread->ctx, 2555e5db499SStefan Hajnoczi iothread->poll_max_ns, 2565e5db499SStefan Hajnoczi iothread->poll_grow, 2575e5db499SStefan Hajnoczi iothread->poll_shrink, 258dcfe4805SMarkus Armbruster errp); 2590d9d86fbSStefan Hajnoczi } 2600d9d86fbSStefan Hajnoczi } 2610d9d86fbSStefan Hajnoczi 262be8d8537SStefan Hajnoczi static void iothread_class_init(ObjectClass *klass, void *class_data) 263be8d8537SStefan Hajnoczi { 264be8d8537SStefan Hajnoczi UserCreatableClass *ucc = USER_CREATABLE_CLASS(klass); 265be8d8537SStefan Hajnoczi ucc->complete = iothread_complete; 2660d9d86fbSStefan Hajnoczi 2670d9d86fbSStefan Hajnoczi object_class_property_add(klass, "poll-max-ns", "int", 2685e5db499SStefan Hajnoczi iothread_get_poll_param, 2695e5db499SStefan Hajnoczi iothread_set_poll_param, 270d2623129SMarkus Armbruster NULL, &poll_max_ns_info); 2715e5db499SStefan Hajnoczi object_class_property_add(klass, "poll-grow", "int", 2725e5db499SStefan Hajnoczi iothread_get_poll_param, 2735e5db499SStefan Hajnoczi iothread_set_poll_param, 274d2623129SMarkus Armbruster NULL, &poll_grow_info); 2755e5db499SStefan Hajnoczi object_class_property_add(klass, "poll-shrink", "int", 2765e5db499SStefan Hajnoczi iothread_get_poll_param, 2775e5db499SStefan Hajnoczi iothread_set_poll_param, 278d2623129SMarkus Armbruster NULL, &poll_shrink_info); 279be8d8537SStefan Hajnoczi } 280be8d8537SStefan Hajnoczi 281be8d8537SStefan Hajnoczi static const TypeInfo iothread_info = { 282be8d8537SStefan Hajnoczi .name = TYPE_IOTHREAD, 283be8d8537SStefan Hajnoczi .parent = TYPE_OBJECT, 284be8d8537SStefan Hajnoczi .class_init = iothread_class_init, 285be8d8537SStefan Hajnoczi .instance_size = sizeof(IOThread), 286cdd7abfdSStefan Hajnoczi .instance_init = iothread_instance_init, 287be8d8537SStefan Hajnoczi .instance_finalize = iothread_instance_finalize, 288be8d8537SStefan Hajnoczi .interfaces = (InterfaceInfo[]) { 289be8d8537SStefan Hajnoczi {TYPE_USER_CREATABLE}, 290be8d8537SStefan Hajnoczi {} 291be8d8537SStefan Hajnoczi }, 292be8d8537SStefan Hajnoczi }; 293be8d8537SStefan Hajnoczi 294be8d8537SStefan Hajnoczi static void iothread_register_types(void) 295be8d8537SStefan Hajnoczi { 296be8d8537SStefan Hajnoczi type_register_static(&iothread_info); 297be8d8537SStefan Hajnoczi } 298be8d8537SStefan Hajnoczi 299be8d8537SStefan Hajnoczi type_init(iothread_register_types) 300be8d8537SStefan Hajnoczi 301be8d8537SStefan Hajnoczi char *iothread_get_id(IOThread *iothread) 302be8d8537SStefan Hajnoczi { 3037a309cc9SMarkus Armbruster return g_strdup(object_get_canonical_path_component(OBJECT(iothread))); 304be8d8537SStefan Hajnoczi } 305be8d8537SStefan Hajnoczi 306be8d8537SStefan Hajnoczi AioContext *iothread_get_aio_context(IOThread *iothread) 307be8d8537SStefan Hajnoczi { 308be8d8537SStefan Hajnoczi return iothread->ctx; 309be8d8537SStefan Hajnoczi } 310dc3dd0d2SStefan Hajnoczi 311dc3dd0d2SStefan Hajnoczi static int query_one_iothread(Object *object, void *opaque) 312dc3dd0d2SStefan Hajnoczi { 313dc3dd0d2SStefan Hajnoczi IOThreadInfoList ***prev = opaque; 314dc3dd0d2SStefan Hajnoczi IOThreadInfoList *elem; 315dc3dd0d2SStefan Hajnoczi IOThreadInfo *info; 316dc3dd0d2SStefan Hajnoczi IOThread *iothread; 317dc3dd0d2SStefan Hajnoczi 318dc3dd0d2SStefan Hajnoczi iothread = (IOThread *)object_dynamic_cast(object, TYPE_IOTHREAD); 319dc3dd0d2SStefan Hajnoczi if (!iothread) { 320dc3dd0d2SStefan Hajnoczi return 0; 321dc3dd0d2SStefan Hajnoczi } 322dc3dd0d2SStefan Hajnoczi 323dc3dd0d2SStefan Hajnoczi info = g_new0(IOThreadInfo, 1); 324dc3dd0d2SStefan Hajnoczi info->id = iothread_get_id(iothread); 325dc3dd0d2SStefan Hajnoczi info->thread_id = iothread->thread_id; 3265fc00480SPavel Hrdina info->poll_max_ns = iothread->poll_max_ns; 3275fc00480SPavel Hrdina info->poll_grow = iothread->poll_grow; 3285fc00480SPavel Hrdina info->poll_shrink = iothread->poll_shrink; 329dc3dd0d2SStefan Hajnoczi 330dc3dd0d2SStefan Hajnoczi elem = g_new0(IOThreadInfoList, 1); 331dc3dd0d2SStefan Hajnoczi elem->value = info; 332dc3dd0d2SStefan Hajnoczi elem->next = NULL; 333dc3dd0d2SStefan Hajnoczi 334dc3dd0d2SStefan Hajnoczi **prev = elem; 335dc3dd0d2SStefan Hajnoczi *prev = &elem->next; 336dc3dd0d2SStefan Hajnoczi return 0; 337dc3dd0d2SStefan Hajnoczi } 338dc3dd0d2SStefan Hajnoczi 339dc3dd0d2SStefan Hajnoczi IOThreadInfoList *qmp_query_iothreads(Error **errp) 340dc3dd0d2SStefan Hajnoczi { 341dc3dd0d2SStefan Hajnoczi IOThreadInfoList *head = NULL; 342dc3dd0d2SStefan Hajnoczi IOThreadInfoList **prev = &head; 343bc2256c4SDaniel P. Berrange Object *container = object_get_objects_root(); 344dc3dd0d2SStefan Hajnoczi 345dc3dd0d2SStefan Hajnoczi object_child_foreach(container, query_one_iothread, &prev); 346dc3dd0d2SStefan Hajnoczi return head; 347dc3dd0d2SStefan Hajnoczi } 348dce8921bSFam Zheng 349329163cbSWang Yong GMainContext *iothread_get_g_main_context(IOThread *iothread) 350329163cbSWang Yong { 351*d73415a3SStefan Hajnoczi qatomic_set(&iothread->run_gcontext, 1); 352b506e0f1SPeter Xu aio_notify(iothread->ctx); 353329163cbSWang Yong return iothread->worker_context; 354329163cbSWang Yong } 3550173e21bSPeter Xu 3560173e21bSPeter Xu IOThread *iothread_create(const char *id, Error **errp) 3570173e21bSPeter Xu { 3580173e21bSPeter Xu Object *obj; 3590173e21bSPeter Xu 3600173e21bSPeter Xu obj = object_new_with_props(TYPE_IOTHREAD, 3610173e21bSPeter Xu object_get_internal_root(), 3620173e21bSPeter Xu id, errp, NULL); 3630173e21bSPeter Xu 3640173e21bSPeter Xu return IOTHREAD(obj); 3650173e21bSPeter Xu } 3660173e21bSPeter Xu 3670173e21bSPeter Xu void iothread_destroy(IOThread *iothread) 3680173e21bSPeter Xu { 3690173e21bSPeter Xu object_unparent(OBJECT(iothread)); 3700173e21bSPeter Xu } 371fbcc6923SStefan Hajnoczi 372fbcc6923SStefan Hajnoczi /* Lookup IOThread by its id. Only finds user-created objects, not internal 373fbcc6923SStefan Hajnoczi * iothread_create() objects. */ 374fbcc6923SStefan Hajnoczi IOThread *iothread_by_id(const char *id) 375fbcc6923SStefan Hajnoczi { 376fbcc6923SStefan Hajnoczi return IOTHREAD(object_resolve_path_type(id, TYPE_IOTHREAD, NULL)); 377fbcc6923SStefan Hajnoczi } 378