module: Don't complain when a module is absent
[qemu/ar7.git] / iothread.c
blobd9403cf69ed2f09f546fa67ec56fd549a34455fd
1 /*
2 * Event loop thread
4 * Copyright Red Hat Inc., 2013
6 * Authors:
7 * Stefan Hajnoczi <stefanha@redhat.com>
9 * This work is licensed under the terms of the GNU GPL, version 2 or later.
10 * See the COPYING file in the top-level directory.
14 #include "qom/object.h"
15 #include "qom/object_interfaces.h"
16 #include "qemu/module.h"
17 #include "block/aio.h"
18 #include "sysemu/iothread.h"
19 #include "qmp-commands.h"
21 #define IOTHREADS_PATH "/objects"
23 typedef ObjectClass IOThreadClass;
25 #define IOTHREAD_GET_CLASS(obj) \
26 OBJECT_GET_CLASS(IOThreadClass, obj, TYPE_IOTHREAD)
27 #define IOTHREAD_CLASS(klass) \
28 OBJECT_CLASS_CHECK(IOThreadClass, klass, TYPE_IOTHREAD)
30 static void *iothread_run(void *opaque)
32 IOThread *iothread = opaque;
33 bool blocking;
35 qemu_mutex_lock(&iothread->init_done_lock);
36 iothread->thread_id = qemu_get_thread_id();
37 qemu_cond_signal(&iothread->init_done_cond);
38 qemu_mutex_unlock(&iothread->init_done_lock);
40 while (!iothread->stopping) {
41 aio_context_acquire(iothread->ctx);
42 blocking = true;
43 while (!iothread->stopping && aio_poll(iothread->ctx, blocking)) {
44 /* Progress was made, keep going */
45 blocking = false;
47 aio_context_release(iothread->ctx);
49 return NULL;
52 static void iothread_instance_finalize(Object *obj)
54 IOThread *iothread = IOTHREAD(obj);
56 iothread->stopping = true;
57 aio_notify(iothread->ctx);
58 qemu_thread_join(&iothread->thread);
59 qemu_cond_destroy(&iothread->init_done_cond);
60 qemu_mutex_destroy(&iothread->init_done_lock);
61 aio_context_unref(iothread->ctx);
64 static void iothread_complete(UserCreatable *obj, Error **errp)
66 IOThread *iothread = IOTHREAD(obj);
68 iothread->stopping = false;
69 iothread->ctx = aio_context_new();
70 iothread->thread_id = -1;
72 qemu_mutex_init(&iothread->init_done_lock);
73 qemu_cond_init(&iothread->init_done_cond);
75 /* This assumes we are called from a thread with useful CPU affinity for us
76 * to inherit.
78 qemu_thread_create(&iothread->thread, "iothread", iothread_run,
79 iothread, QEMU_THREAD_JOINABLE);
81 /* Wait for initialization to complete */
82 qemu_mutex_lock(&iothread->init_done_lock);
83 while (iothread->thread_id == -1) {
84 qemu_cond_wait(&iothread->init_done_cond,
85 &iothread->init_done_lock);
87 qemu_mutex_unlock(&iothread->init_done_lock);
90 static void iothread_class_init(ObjectClass *klass, void *class_data)
92 UserCreatableClass *ucc = USER_CREATABLE_CLASS(klass);
93 ucc->complete = iothread_complete;
96 static const TypeInfo iothread_info = {
97 .name = TYPE_IOTHREAD,
98 .parent = TYPE_OBJECT,
99 .class_init = iothread_class_init,
100 .instance_size = sizeof(IOThread),
101 .instance_finalize = iothread_instance_finalize,
102 .interfaces = (InterfaceInfo[]) {
103 {TYPE_USER_CREATABLE},
108 static void iothread_register_types(void)
110 type_register_static(&iothread_info);
113 type_init(iothread_register_types)
115 IOThread *iothread_find(const char *id)
117 Object *container = container_get(object_get_root(), IOTHREADS_PATH);
118 Object *child;
120 child = object_property_get_link(container, id, NULL);
121 if (!child) {
122 return NULL;
124 return (IOThread *)object_dynamic_cast(child, TYPE_IOTHREAD);
127 char *iothread_get_id(IOThread *iothread)
129 return object_get_canonical_path_component(OBJECT(iothread));
132 AioContext *iothread_get_aio_context(IOThread *iothread)
134 return iothread->ctx;
137 static int query_one_iothread(Object *object, void *opaque)
139 IOThreadInfoList ***prev = opaque;
140 IOThreadInfoList *elem;
141 IOThreadInfo *info;
142 IOThread *iothread;
144 iothread = (IOThread *)object_dynamic_cast(object, TYPE_IOTHREAD);
145 if (!iothread) {
146 return 0;
149 info = g_new0(IOThreadInfo, 1);
150 info->id = iothread_get_id(iothread);
151 info->thread_id = iothread->thread_id;
153 elem = g_new0(IOThreadInfoList, 1);
154 elem->value = info;
155 elem->next = NULL;
157 **prev = elem;
158 *prev = &elem->next;
159 return 0;
162 IOThreadInfoList *qmp_query_iothreads(Error **errp)
164 IOThreadInfoList *head = NULL;
165 IOThreadInfoList **prev = &head;
166 Object *container = container_get(object_get_root(), IOTHREADS_PATH);
168 object_child_foreach(container, query_one_iothread, &prev);
169 return head;