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" 21dc3dd0d2SStefan Hajnoczi #include "qmp-commands.h" 222f78e491SChrysostomos Nanakos #include "qemu/error-report.h" 23ab28bd23SPaolo Bonzini #include "qemu/rcu.h" 24e4370165SPaolo Bonzini #include "qemu/main-loop.h" 25be8d8537SStefan Hajnoczi 26be8d8537SStefan Hajnoczi typedef ObjectClass IOThreadClass; 27be8d8537SStefan Hajnoczi 28be8d8537SStefan Hajnoczi #define IOTHREAD_GET_CLASS(obj) \ 29be8d8537SStefan Hajnoczi OBJECT_GET_CLASS(IOThreadClass, obj, TYPE_IOTHREAD) 30be8d8537SStefan Hajnoczi #define IOTHREAD_CLASS(klass) \ 31be8d8537SStefan Hajnoczi OBJECT_CLASS_CHECK(IOThreadClass, klass, TYPE_IOTHREAD) 32be8d8537SStefan Hajnoczi 33e4370165SPaolo Bonzini static __thread IOThread *my_iothread; 34e4370165SPaolo Bonzini 35e4370165SPaolo Bonzini AioContext *qemu_get_current_aio_context(void) 36e4370165SPaolo Bonzini { 37e4370165SPaolo Bonzini return my_iothread ? my_iothread->ctx : qemu_get_aio_context(); 38e4370165SPaolo Bonzini } 39e4370165SPaolo Bonzini 40be8d8537SStefan Hajnoczi static void *iothread_run(void *opaque) 41be8d8537SStefan Hajnoczi { 42be8d8537SStefan Hajnoczi IOThread *iothread = opaque; 43be8d8537SStefan Hajnoczi 44ab28bd23SPaolo Bonzini rcu_register_thread(); 45ab28bd23SPaolo Bonzini 46e4370165SPaolo 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 5265c1b5b6SPaolo Bonzini while (!atomic_read(&iothread->stopping)) { 5365c1b5b6SPaolo Bonzini aio_poll(iothread->ctx, true); 54be8d8537SStefan Hajnoczi } 55ab28bd23SPaolo Bonzini 56ab28bd23SPaolo Bonzini rcu_unregister_thread(); 57be8d8537SStefan Hajnoczi return NULL; 58be8d8537SStefan Hajnoczi } 59be8d8537SStefan Hajnoczi 60dce8921bSFam Zheng static int iothread_stop(Object *object, void *opaque) 61be8d8537SStefan Hajnoczi { 62dce8921bSFam Zheng IOThread *iothread; 63be8d8537SStefan Hajnoczi 64dce8921bSFam Zheng iothread = (IOThread *)object_dynamic_cast(object, TYPE_IOTHREAD); 65dce8921bSFam Zheng if (!iothread || !iothread->ctx) { 66dce8921bSFam Zheng return 0; 672f78e491SChrysostomos Nanakos } 68be8d8537SStefan Hajnoczi iothread->stopping = true; 69be8d8537SStefan Hajnoczi aio_notify(iothread->ctx); 70be8d8537SStefan Hajnoczi qemu_thread_join(&iothread->thread); 71dce8921bSFam Zheng return 0; 72dce8921bSFam Zheng } 73dce8921bSFam Zheng 74dce8921bSFam Zheng static void iothread_instance_finalize(Object *obj) 75dce8921bSFam Zheng { 76dce8921bSFam Zheng IOThread *iothread = IOTHREAD(obj); 77dce8921bSFam Zheng 78dce8921bSFam Zheng iothread_stop(obj, NULL); 7988eb7c29SStefan Hajnoczi qemu_cond_destroy(&iothread->init_done_cond); 8088eb7c29SStefan Hajnoczi qemu_mutex_destroy(&iothread->init_done_lock); 81eb7b5c35SLin Ma if (!iothread->ctx) { 82eb7b5c35SLin Ma return; 83eb7b5c35SLin Ma } 84be8d8537SStefan Hajnoczi aio_context_unref(iothread->ctx); 85be8d8537SStefan Hajnoczi } 86be8d8537SStefan Hajnoczi 87be8d8537SStefan Hajnoczi static void iothread_complete(UserCreatable *obj, Error **errp) 88be8d8537SStefan Hajnoczi { 892f78e491SChrysostomos Nanakos Error *local_error = NULL; 90be8d8537SStefan Hajnoczi IOThread *iothread = IOTHREAD(obj); 91d21e8776SPaolo Bonzini char *name, *thread_name; 92be8d8537SStefan Hajnoczi 93be8d8537SStefan Hajnoczi iothread->stopping = false; 9488eb7c29SStefan Hajnoczi iothread->thread_id = -1; 952f78e491SChrysostomos Nanakos iothread->ctx = aio_context_new(&local_error); 962f78e491SChrysostomos Nanakos if (!iothread->ctx) { 972f78e491SChrysostomos Nanakos error_propagate(errp, local_error); 982f78e491SChrysostomos Nanakos return; 992f78e491SChrysostomos Nanakos } 10088eb7c29SStefan Hajnoczi 101*0d9d86fbSStefan Hajnoczi aio_context_set_poll_params(iothread->ctx, iothread->poll_max_ns, 102*0d9d86fbSStefan Hajnoczi &local_error); 103*0d9d86fbSStefan Hajnoczi if (local_error) { 104*0d9d86fbSStefan Hajnoczi error_propagate(errp, local_error); 105*0d9d86fbSStefan Hajnoczi aio_context_unref(iothread->ctx); 106*0d9d86fbSStefan Hajnoczi iothread->ctx = NULL; 107*0d9d86fbSStefan Hajnoczi return; 108*0d9d86fbSStefan Hajnoczi } 109*0d9d86fbSStefan Hajnoczi 11088eb7c29SStefan Hajnoczi qemu_mutex_init(&iothread->init_done_lock); 11188eb7c29SStefan Hajnoczi qemu_cond_init(&iothread->init_done_cond); 112be8d8537SStefan Hajnoczi 113be8d8537SStefan Hajnoczi /* This assumes we are called from a thread with useful CPU affinity for us 114be8d8537SStefan Hajnoczi * to inherit. 115be8d8537SStefan Hajnoczi */ 116d21e8776SPaolo Bonzini name = object_get_canonical_path_component(OBJECT(obj)); 117d21e8776SPaolo Bonzini thread_name = g_strdup_printf("IO %s", name); 118d21e8776SPaolo Bonzini qemu_thread_create(&iothread->thread, thread_name, iothread_run, 119be8d8537SStefan Hajnoczi iothread, QEMU_THREAD_JOINABLE); 120d21e8776SPaolo Bonzini g_free(thread_name); 121d21e8776SPaolo Bonzini g_free(name); 12288eb7c29SStefan Hajnoczi 12388eb7c29SStefan Hajnoczi /* Wait for initialization to complete */ 12488eb7c29SStefan Hajnoczi qemu_mutex_lock(&iothread->init_done_lock); 12588eb7c29SStefan Hajnoczi while (iothread->thread_id == -1) { 12688eb7c29SStefan Hajnoczi qemu_cond_wait(&iothread->init_done_cond, 12788eb7c29SStefan Hajnoczi &iothread->init_done_lock); 12888eb7c29SStefan Hajnoczi } 12988eb7c29SStefan Hajnoczi qemu_mutex_unlock(&iothread->init_done_lock); 130be8d8537SStefan Hajnoczi } 131be8d8537SStefan Hajnoczi 132*0d9d86fbSStefan Hajnoczi static void iothread_get_poll_max_ns(Object *obj, Visitor *v, 133*0d9d86fbSStefan Hajnoczi const char *name, void *opaque, Error **errp) 134*0d9d86fbSStefan Hajnoczi { 135*0d9d86fbSStefan Hajnoczi IOThread *iothread = IOTHREAD(obj); 136*0d9d86fbSStefan Hajnoczi 137*0d9d86fbSStefan Hajnoczi visit_type_int64(v, name, &iothread->poll_max_ns, errp); 138*0d9d86fbSStefan Hajnoczi } 139*0d9d86fbSStefan Hajnoczi 140*0d9d86fbSStefan Hajnoczi static void iothread_set_poll_max_ns(Object *obj, Visitor *v, 141*0d9d86fbSStefan Hajnoczi const char *name, void *opaque, Error **errp) 142*0d9d86fbSStefan Hajnoczi { 143*0d9d86fbSStefan Hajnoczi IOThread *iothread = IOTHREAD(obj); 144*0d9d86fbSStefan Hajnoczi Error *local_err = NULL; 145*0d9d86fbSStefan Hajnoczi int64_t value; 146*0d9d86fbSStefan Hajnoczi 147*0d9d86fbSStefan Hajnoczi visit_type_int64(v, name, &value, &local_err); 148*0d9d86fbSStefan Hajnoczi if (local_err) { 149*0d9d86fbSStefan Hajnoczi goto out; 150*0d9d86fbSStefan Hajnoczi } 151*0d9d86fbSStefan Hajnoczi 152*0d9d86fbSStefan Hajnoczi if (value < 0) { 153*0d9d86fbSStefan Hajnoczi error_setg(&local_err, "poll_max_ns value must be in range " 154*0d9d86fbSStefan Hajnoczi "[0, %"PRId64"]", INT64_MAX); 155*0d9d86fbSStefan Hajnoczi goto out; 156*0d9d86fbSStefan Hajnoczi } 157*0d9d86fbSStefan Hajnoczi 158*0d9d86fbSStefan Hajnoczi iothread->poll_max_ns = value; 159*0d9d86fbSStefan Hajnoczi 160*0d9d86fbSStefan Hajnoczi if (iothread->ctx) { 161*0d9d86fbSStefan Hajnoczi aio_context_set_poll_params(iothread->ctx, value, &local_err); 162*0d9d86fbSStefan Hajnoczi } 163*0d9d86fbSStefan Hajnoczi 164*0d9d86fbSStefan Hajnoczi out: 165*0d9d86fbSStefan Hajnoczi error_propagate(errp, local_err); 166*0d9d86fbSStefan Hajnoczi } 167*0d9d86fbSStefan Hajnoczi 168be8d8537SStefan Hajnoczi static void iothread_class_init(ObjectClass *klass, void *class_data) 169be8d8537SStefan Hajnoczi { 170be8d8537SStefan Hajnoczi UserCreatableClass *ucc = USER_CREATABLE_CLASS(klass); 171be8d8537SStefan Hajnoczi ucc->complete = iothread_complete; 172*0d9d86fbSStefan Hajnoczi 173*0d9d86fbSStefan Hajnoczi object_class_property_add(klass, "poll-max-ns", "int", 174*0d9d86fbSStefan Hajnoczi iothread_get_poll_max_ns, 175*0d9d86fbSStefan Hajnoczi iothread_set_poll_max_ns, 176*0d9d86fbSStefan Hajnoczi NULL, NULL, &error_abort); 177be8d8537SStefan Hajnoczi } 178be8d8537SStefan Hajnoczi 179be8d8537SStefan Hajnoczi static const TypeInfo iothread_info = { 180be8d8537SStefan Hajnoczi .name = TYPE_IOTHREAD, 181be8d8537SStefan Hajnoczi .parent = TYPE_OBJECT, 182be8d8537SStefan Hajnoczi .class_init = iothread_class_init, 183be8d8537SStefan Hajnoczi .instance_size = sizeof(IOThread), 184be8d8537SStefan Hajnoczi .instance_finalize = iothread_instance_finalize, 185be8d8537SStefan Hajnoczi .interfaces = (InterfaceInfo[]) { 186be8d8537SStefan Hajnoczi {TYPE_USER_CREATABLE}, 187be8d8537SStefan Hajnoczi {} 188be8d8537SStefan Hajnoczi }, 189be8d8537SStefan Hajnoczi }; 190be8d8537SStefan Hajnoczi 191be8d8537SStefan Hajnoczi static void iothread_register_types(void) 192be8d8537SStefan Hajnoczi { 193be8d8537SStefan Hajnoczi type_register_static(&iothread_info); 194be8d8537SStefan Hajnoczi } 195be8d8537SStefan Hajnoczi 196be8d8537SStefan Hajnoczi type_init(iothread_register_types) 197be8d8537SStefan Hajnoczi 198be8d8537SStefan Hajnoczi char *iothread_get_id(IOThread *iothread) 199be8d8537SStefan Hajnoczi { 200be8d8537SStefan Hajnoczi return object_get_canonical_path_component(OBJECT(iothread)); 201be8d8537SStefan Hajnoczi } 202be8d8537SStefan Hajnoczi 203be8d8537SStefan Hajnoczi AioContext *iothread_get_aio_context(IOThread *iothread) 204be8d8537SStefan Hajnoczi { 205be8d8537SStefan Hajnoczi return iothread->ctx; 206be8d8537SStefan Hajnoczi } 207dc3dd0d2SStefan Hajnoczi 208dc3dd0d2SStefan Hajnoczi static int query_one_iothread(Object *object, void *opaque) 209dc3dd0d2SStefan Hajnoczi { 210dc3dd0d2SStefan Hajnoczi IOThreadInfoList ***prev = opaque; 211dc3dd0d2SStefan Hajnoczi IOThreadInfoList *elem; 212dc3dd0d2SStefan Hajnoczi IOThreadInfo *info; 213dc3dd0d2SStefan Hajnoczi IOThread *iothread; 214dc3dd0d2SStefan Hajnoczi 215dc3dd0d2SStefan Hajnoczi iothread = (IOThread *)object_dynamic_cast(object, TYPE_IOTHREAD); 216dc3dd0d2SStefan Hajnoczi if (!iothread) { 217dc3dd0d2SStefan Hajnoczi return 0; 218dc3dd0d2SStefan Hajnoczi } 219dc3dd0d2SStefan Hajnoczi 220dc3dd0d2SStefan Hajnoczi info = g_new0(IOThreadInfo, 1); 221dc3dd0d2SStefan Hajnoczi info->id = iothread_get_id(iothread); 222dc3dd0d2SStefan Hajnoczi info->thread_id = iothread->thread_id; 223dc3dd0d2SStefan Hajnoczi 224dc3dd0d2SStefan Hajnoczi elem = g_new0(IOThreadInfoList, 1); 225dc3dd0d2SStefan Hajnoczi elem->value = info; 226dc3dd0d2SStefan Hajnoczi elem->next = NULL; 227dc3dd0d2SStefan Hajnoczi 228dc3dd0d2SStefan Hajnoczi **prev = elem; 229dc3dd0d2SStefan Hajnoczi *prev = &elem->next; 230dc3dd0d2SStefan Hajnoczi return 0; 231dc3dd0d2SStefan Hajnoczi } 232dc3dd0d2SStefan Hajnoczi 233dc3dd0d2SStefan Hajnoczi IOThreadInfoList *qmp_query_iothreads(Error **errp) 234dc3dd0d2SStefan Hajnoczi { 235dc3dd0d2SStefan Hajnoczi IOThreadInfoList *head = NULL; 236dc3dd0d2SStefan Hajnoczi IOThreadInfoList **prev = &head; 237bc2256c4SDaniel P. Berrange Object *container = object_get_objects_root(); 238dc3dd0d2SStefan Hajnoczi 239dc3dd0d2SStefan Hajnoczi object_child_foreach(container, query_one_iothread, &prev); 240dc3dd0d2SStefan Hajnoczi return head; 241dc3dd0d2SStefan Hajnoczi } 242dce8921bSFam Zheng 243dce8921bSFam Zheng void iothread_stop_all(void) 244dce8921bSFam Zheng { 245dce8921bSFam Zheng Object *container = object_get_objects_root(); 246d16341faSPaolo Bonzini BlockDriverState *bs; 247d16341faSPaolo Bonzini BdrvNextIterator it; 248d16341faSPaolo Bonzini 249d16341faSPaolo Bonzini for (bs = bdrv_first(&it); bs; bs = bdrv_next(&it)) { 250d16341faSPaolo Bonzini AioContext *ctx = bdrv_get_aio_context(bs); 251d16341faSPaolo Bonzini if (ctx == qemu_get_aio_context()) { 252d16341faSPaolo Bonzini continue; 253d16341faSPaolo Bonzini } 254d16341faSPaolo Bonzini aio_context_acquire(ctx); 255d16341faSPaolo Bonzini bdrv_set_aio_context(bs, qemu_get_aio_context()); 256d16341faSPaolo Bonzini aio_context_release(ctx); 257d16341faSPaolo Bonzini } 258dce8921bSFam Zheng 259dce8921bSFam Zheng object_child_foreach(container, iothread_stop, NULL); 260dce8921bSFam Zheng } 261