| /* |
| * Event loop thread |
| * |
| * Copyright Red Hat Inc., 2013 |
| * |
| * Authors: |
| * Stefan Hajnoczi <stefanha@redhat.com> |
| * |
| * This work is licensed under the terms of the GNU GPL, version 2 or later. |
| * See the COPYING file in the top-level directory. |
| * |
| */ |
| |
| #include "qemu/osdep.h" |
| #include "qom/object.h" |
| #include "qom/object_interfaces.h" |
| #include "qemu/module.h" |
| #include "block/aio.h" |
| #include "block/block.h" |
| #include "sysemu/iothread.h" |
| #include "qmp-commands.h" |
| #include "qemu/error-report.h" |
| #include "qemu/rcu.h" |
| #include "qemu/main-loop.h" |
| |
| typedef ObjectClass IOThreadClass; |
| |
| #define IOTHREAD_GET_CLASS(obj) \ |
| OBJECT_GET_CLASS(IOThreadClass, obj, TYPE_IOTHREAD) |
| #define IOTHREAD_CLASS(klass) \ |
| OBJECT_CLASS_CHECK(IOThreadClass, klass, TYPE_IOTHREAD) |
| |
| static __thread IOThread *my_iothread; |
| |
| AioContext *qemu_get_current_aio_context(void) |
| { |
| return my_iothread ? my_iothread->ctx : qemu_get_aio_context(); |
| } |
| |
| static void *iothread_run(void *opaque) |
| { |
| IOThread *iothread = opaque; |
| |
| rcu_register_thread(); |
| |
| my_iothread = iothread; |
| qemu_mutex_lock(&iothread->init_done_lock); |
| iothread->thread_id = qemu_get_thread_id(); |
| qemu_cond_signal(&iothread->init_done_cond); |
| qemu_mutex_unlock(&iothread->init_done_lock); |
| |
| while (!atomic_read(&iothread->stopping)) { |
| aio_poll(iothread->ctx, true); |
| } |
| |
| rcu_unregister_thread(); |
| return NULL; |
| } |
| |
| static int iothread_stop(Object *object, void *opaque) |
| { |
| IOThread *iothread; |
| |
| iothread = (IOThread *)object_dynamic_cast(object, TYPE_IOTHREAD); |
| if (!iothread || !iothread->ctx) { |
| return 0; |
| } |
| iothread->stopping = true; |
| aio_notify(iothread->ctx); |
| qemu_thread_join(&iothread->thread); |
| return 0; |
| } |
| |
| static void iothread_instance_finalize(Object *obj) |
| { |
| IOThread *iothread = IOTHREAD(obj); |
| |
| iothread_stop(obj, NULL); |
| qemu_cond_destroy(&iothread->init_done_cond); |
| qemu_mutex_destroy(&iothread->init_done_lock); |
| if (!iothread->ctx) { |
| return; |
| } |
| aio_context_unref(iothread->ctx); |
| } |
| |
| static void iothread_complete(UserCreatable *obj, Error **errp) |
| { |
| Error *local_error = NULL; |
| IOThread *iothread = IOTHREAD(obj); |
| char *name, *thread_name; |
| |
| iothread->stopping = false; |
| iothread->thread_id = -1; |
| iothread->ctx = aio_context_new(&local_error); |
| if (!iothread->ctx) { |
| error_propagate(errp, local_error); |
| return; |
| } |
| |
| aio_context_set_poll_params(iothread->ctx, |
| iothread->poll_max_ns, |
| iothread->poll_grow, |
| iothread->poll_shrink, |
| &local_error); |
| if (local_error) { |
| error_propagate(errp, local_error); |
| aio_context_unref(iothread->ctx); |
| iothread->ctx = NULL; |
| return; |
| } |
| |
| qemu_mutex_init(&iothread->init_done_lock); |
| qemu_cond_init(&iothread->init_done_cond); |
| |
| /* This assumes we are called from a thread with useful CPU affinity for us |
| * to inherit. |
| */ |
| name = object_get_canonical_path_component(OBJECT(obj)); |
| thread_name = g_strdup_printf("IO %s", name); |
| qemu_thread_create(&iothread->thread, thread_name, iothread_run, |
| iothread, QEMU_THREAD_JOINABLE); |
| g_free(thread_name); |
| g_free(name); |
| |
| /* Wait for initialization to complete */ |
| qemu_mutex_lock(&iothread->init_done_lock); |
| while (iothread->thread_id == -1) { |
| qemu_cond_wait(&iothread->init_done_cond, |
| &iothread->init_done_lock); |
| } |
| qemu_mutex_unlock(&iothread->init_done_lock); |
| } |
| |
| typedef struct { |
| const char *name; |
| ptrdiff_t offset; /* field's byte offset in IOThread struct */ |
| } PollParamInfo; |
| |
| static PollParamInfo poll_max_ns_info = { |
| "poll-max-ns", offsetof(IOThread, poll_max_ns), |
| }; |
| static PollParamInfo poll_grow_info = { |
| "poll-grow", offsetof(IOThread, poll_grow), |
| }; |
| static PollParamInfo poll_shrink_info = { |
| "poll-shrink", offsetof(IOThread, poll_shrink), |
| }; |
| |
| static void iothread_get_poll_param(Object *obj, Visitor *v, |
| const char *name, void *opaque, Error **errp) |
| { |
| IOThread *iothread = IOTHREAD(obj); |
| PollParamInfo *info = opaque; |
| int64_t *field = (void *)iothread + info->offset; |
| |
| visit_type_int64(v, name, field, errp); |
| } |
| |
| static void iothread_set_poll_param(Object *obj, Visitor *v, |
| const char *name, void *opaque, Error **errp) |
| { |
| IOThread *iothread = IOTHREAD(obj); |
| PollParamInfo *info = opaque; |
| int64_t *field = (void *)iothread + info->offset; |
| Error *local_err = NULL; |
| int64_t value; |
| |
| visit_type_int64(v, name, &value, &local_err); |
| if (local_err) { |
| goto out; |
| } |
| |
| if (value < 0) { |
| error_setg(&local_err, "%s value must be in range [0, %"PRId64"]", |
| info->name, INT64_MAX); |
| goto out; |
| } |
| |
| *field = value; |
| |
| if (iothread->ctx) { |
| aio_context_set_poll_params(iothread->ctx, |
| iothread->poll_max_ns, |
| iothread->poll_grow, |
| iothread->poll_shrink, |
| &local_err); |
| } |
| |
| out: |
| error_propagate(errp, local_err); |
| } |
| |
| static void iothread_class_init(ObjectClass *klass, void *class_data) |
| { |
| UserCreatableClass *ucc = USER_CREATABLE_CLASS(klass); |
| ucc->complete = iothread_complete; |
| |
| object_class_property_add(klass, "poll-max-ns", "int", |
| iothread_get_poll_param, |
| iothread_set_poll_param, |
| NULL, &poll_max_ns_info, &error_abort); |
| object_class_property_add(klass, "poll-grow", "int", |
| iothread_get_poll_param, |
| iothread_set_poll_param, |
| NULL, &poll_grow_info, &error_abort); |
| object_class_property_add(klass, "poll-shrink", "int", |
| iothread_get_poll_param, |
| iothread_set_poll_param, |
| NULL, &poll_shrink_info, &error_abort); |
| } |
| |
| static const TypeInfo iothread_info = { |
| .name = TYPE_IOTHREAD, |
| .parent = TYPE_OBJECT, |
| .class_init = iothread_class_init, |
| .instance_size = sizeof(IOThread), |
| .instance_finalize = iothread_instance_finalize, |
| .interfaces = (InterfaceInfo[]) { |
| {TYPE_USER_CREATABLE}, |
| {} |
| }, |
| }; |
| |
| static void iothread_register_types(void) |
| { |
| type_register_static(&iothread_info); |
| } |
| |
| type_init(iothread_register_types) |
| |
| char *iothread_get_id(IOThread *iothread) |
| { |
| return object_get_canonical_path_component(OBJECT(iothread)); |
| } |
| |
| AioContext *iothread_get_aio_context(IOThread *iothread) |
| { |
| return iothread->ctx; |
| } |
| |
| static int query_one_iothread(Object *object, void *opaque) |
| { |
| IOThreadInfoList ***prev = opaque; |
| IOThreadInfoList *elem; |
| IOThreadInfo *info; |
| IOThread *iothread; |
| |
| iothread = (IOThread *)object_dynamic_cast(object, TYPE_IOTHREAD); |
| if (!iothread) { |
| return 0; |
| } |
| |
| info = g_new0(IOThreadInfo, 1); |
| info->id = iothread_get_id(iothread); |
| info->thread_id = iothread->thread_id; |
| |
| elem = g_new0(IOThreadInfoList, 1); |
| elem->value = info; |
| elem->next = NULL; |
| |
| **prev = elem; |
| *prev = &elem->next; |
| return 0; |
| } |
| |
| IOThreadInfoList *qmp_query_iothreads(Error **errp) |
| { |
| IOThreadInfoList *head = NULL; |
| IOThreadInfoList **prev = &head; |
| Object *container = object_get_objects_root(); |
| |
| object_child_foreach(container, query_one_iothread, &prev); |
| return head; |
| } |
| |
| void iothread_stop_all(void) |
| { |
| Object *container = object_get_objects_root(); |
| BlockDriverState *bs; |
| BdrvNextIterator it; |
| |
| for (bs = bdrv_first(&it); bs; bs = bdrv_next(&it)) { |
| AioContext *ctx = bdrv_get_aio_context(bs); |
| if (ctx == qemu_get_aio_context()) { |
| continue; |
| } |
| aio_context_acquire(ctx); |
| bdrv_set_aio_context(bs, qemu_get_aio_context()); |
| aio_context_release(ctx); |
| } |
| |
| object_child_foreach(container, iothread_stop, NULL); |
| } |