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14#include "qemu/osdep.h"
15#include "qom/object.h"
16#include "qom/object_interfaces.h"
17#include "qemu/module.h"
18#include "block/aio.h"
19#include "block/block.h"
20#include "sysemu/iothread.h"
21#include "qapi/error.h"
22#include "qapi/qapi-commands-misc.h"
23#include "qemu/error-report.h"
24#include "qemu/rcu.h"
25#include "qemu/main-loop.h"
26
27typedef ObjectClass IOThreadClass;
28
29#define IOTHREAD_GET_CLASS(obj) \
30 OBJECT_GET_CLASS(IOThreadClass, obj, TYPE_IOTHREAD)
31#define IOTHREAD_CLASS(klass) \
32 OBJECT_CLASS_CHECK(IOThreadClass, klass, TYPE_IOTHREAD)
33
34#ifdef CONFIG_POSIX
35
36
37
38
39#define IOTHREAD_POLL_MAX_NS_DEFAULT 32768ULL
40#else
41#define IOTHREAD_POLL_MAX_NS_DEFAULT 0ULL
42#endif
43
44static __thread IOThread *my_iothread;
45
46AioContext *qemu_get_current_aio_context(void)
47{
48 return my_iothread ? my_iothread->ctx : qemu_get_aio_context();
49}
50
51static void *iothread_run(void *opaque)
52{
53 IOThread *iothread = opaque;
54
55 rcu_register_thread();
56
57 my_iothread = iothread;
58 qemu_mutex_lock(&iothread->init_done_lock);
59 iothread->thread_id = qemu_get_thread_id();
60 qemu_cond_signal(&iothread->init_done_cond);
61 qemu_mutex_unlock(&iothread->init_done_lock);
62
63 while (iothread->running) {
64 aio_poll(iothread->ctx, true);
65
66 if (atomic_read(&iothread->worker_context)) {
67 GMainLoop *loop;
68
69 g_main_context_push_thread_default(iothread->worker_context);
70 iothread->main_loop =
71 g_main_loop_new(iothread->worker_context, TRUE);
72 loop = iothread->main_loop;
73
74 g_main_loop_run(iothread->main_loop);
75 iothread->main_loop = NULL;
76 g_main_loop_unref(loop);
77
78 g_main_context_pop_thread_default(iothread->worker_context);
79 }
80 }
81
82 rcu_unregister_thread();
83 return NULL;
84}
85
86
87static void iothread_stop_bh(void *opaque)
88{
89 IOThread *iothread = opaque;
90
91 iothread->running = false;
92
93 if (iothread->main_loop) {
94 g_main_loop_quit(iothread->main_loop);
95 }
96}
97
98void iothread_stop(IOThread *iothread)
99{
100 if (!iothread->ctx || iothread->stopping) {
101 return;
102 }
103 iothread->stopping = true;
104 aio_bh_schedule_oneshot(iothread->ctx, iothread_stop_bh, iothread);
105 qemu_thread_join(&iothread->thread);
106}
107
108static void iothread_instance_init(Object *obj)
109{
110 IOThread *iothread = IOTHREAD(obj);
111
112 iothread->poll_max_ns = IOTHREAD_POLL_MAX_NS_DEFAULT;
113 iothread->thread_id = -1;
114}
115
116static void iothread_instance_finalize(Object *obj)
117{
118 IOThread *iothread = IOTHREAD(obj);
119
120 iothread_stop(iothread);
121
122 if (iothread->thread_id != -1) {
123 qemu_cond_destroy(&iothread->init_done_cond);
124 qemu_mutex_destroy(&iothread->init_done_lock);
125 }
126
127
128
129
130
131
132
133
134
135
136 if (iothread->ctx) {
137 aio_context_unref(iothread->ctx);
138 iothread->ctx = NULL;
139 }
140 if (iothread->worker_context) {
141 g_main_context_unref(iothread->worker_context);
142 iothread->worker_context = NULL;
143 }
144}
145
146static void iothread_complete(UserCreatable *obj, Error **errp)
147{
148 Error *local_error = NULL;
149 IOThread *iothread = IOTHREAD(obj);
150 char *name, *thread_name;
151
152 iothread->stopping = false;
153 iothread->running = true;
154 iothread->ctx = aio_context_new(&local_error);
155 if (!iothread->ctx) {
156 error_propagate(errp, local_error);
157 return;
158 }
159
160 aio_context_set_poll_params(iothread->ctx,
161 iothread->poll_max_ns,
162 iothread->poll_grow,
163 iothread->poll_shrink,
164 &local_error);
165 if (local_error) {
166 error_propagate(errp, local_error);
167 aio_context_unref(iothread->ctx);
168 iothread->ctx = NULL;
169 return;
170 }
171
172 qemu_mutex_init(&iothread->init_done_lock);
173 qemu_cond_init(&iothread->init_done_cond);
174 iothread->once = (GOnce) G_ONCE_INIT;
175
176
177
178
179 name = object_get_canonical_path_component(OBJECT(obj));
180 thread_name = g_strdup_printf("IO %s", name);
181 qemu_thread_create(&iothread->thread, thread_name, iothread_run,
182 iothread, QEMU_THREAD_JOINABLE);
183 g_free(thread_name);
184 g_free(name);
185
186
187 qemu_mutex_lock(&iothread->init_done_lock);
188 while (iothread->thread_id == -1) {
189 qemu_cond_wait(&iothread->init_done_cond,
190 &iothread->init_done_lock);
191 }
192 qemu_mutex_unlock(&iothread->init_done_lock);
193}
194
195typedef struct {
196 const char *name;
197 ptrdiff_t offset;
198} PollParamInfo;
199
200static PollParamInfo poll_max_ns_info = {
201 "poll-max-ns", offsetof(IOThread, poll_max_ns),
202};
203static PollParamInfo poll_grow_info = {
204 "poll-grow", offsetof(IOThread, poll_grow),
205};
206static PollParamInfo poll_shrink_info = {
207 "poll-shrink", offsetof(IOThread, poll_shrink),
208};
209
210static void iothread_get_poll_param(Object *obj, Visitor *v,
211 const char *name, void *opaque, Error **errp)
212{
213 IOThread *iothread = IOTHREAD(obj);
214 PollParamInfo *info = opaque;
215 int64_t *field = (void *)iothread + info->offset;
216
217 visit_type_int64(v, name, field, errp);
218}
219
220static void iothread_set_poll_param(Object *obj, Visitor *v,
221 const char *name, void *opaque, Error **errp)
222{
223 IOThread *iothread = IOTHREAD(obj);
224 PollParamInfo *info = opaque;
225 int64_t *field = (void *)iothread + info->offset;
226 Error *local_err = NULL;
227 int64_t value;
228
229 visit_type_int64(v, name, &value, &local_err);
230 if (local_err) {
231 goto out;
232 }
233
234 if (value < 0) {
235 error_setg(&local_err, "%s value must be in range [0, %"PRId64"]",
236 info->name, INT64_MAX);
237 goto out;
238 }
239
240 *field = value;
241
242 if (iothread->ctx) {
243 aio_context_set_poll_params(iothread->ctx,
244 iothread->poll_max_ns,
245 iothread->poll_grow,
246 iothread->poll_shrink,
247 &local_err);
248 }
249
250out:
251 error_propagate(errp, local_err);
252}
253
254static void iothread_class_init(ObjectClass *klass, void *class_data)
255{
256 UserCreatableClass *ucc = USER_CREATABLE_CLASS(klass);
257 ucc->complete = iothread_complete;
258
259 object_class_property_add(klass, "poll-max-ns", "int",
260 iothread_get_poll_param,
261 iothread_set_poll_param,
262 NULL, &poll_max_ns_info, &error_abort);
263 object_class_property_add(klass, "poll-grow", "int",
264 iothread_get_poll_param,
265 iothread_set_poll_param,
266 NULL, &poll_grow_info, &error_abort);
267 object_class_property_add(klass, "poll-shrink", "int",
268 iothread_get_poll_param,
269 iothread_set_poll_param,
270 NULL, &poll_shrink_info, &error_abort);
271}
272
273static const TypeInfo iothread_info = {
274 .name = TYPE_IOTHREAD,
275 .parent = TYPE_OBJECT,
276 .class_init = iothread_class_init,
277 .instance_size = sizeof(IOThread),
278 .instance_init = iothread_instance_init,
279 .instance_finalize = iothread_instance_finalize,
280 .interfaces = (InterfaceInfo[]) {
281 {TYPE_USER_CREATABLE},
282 {}
283 },
284};
285
286static void iothread_register_types(void)
287{
288 type_register_static(&iothread_info);
289}
290
291type_init(iothread_register_types)
292
293char *iothread_get_id(IOThread *iothread)
294{
295 return object_get_canonical_path_component(OBJECT(iothread));
296}
297
298AioContext *iothread_get_aio_context(IOThread *iothread)
299{
300 return iothread->ctx;
301}
302
303static int query_one_iothread(Object *object, void *opaque)
304{
305 IOThreadInfoList ***prev = opaque;
306 IOThreadInfoList *elem;
307 IOThreadInfo *info;
308 IOThread *iothread;
309
310 iothread = (IOThread *)object_dynamic_cast(object, TYPE_IOTHREAD);
311 if (!iothread) {
312 return 0;
313 }
314
315 info = g_new0(IOThreadInfo, 1);
316 info->id = iothread_get_id(iothread);
317 info->thread_id = iothread->thread_id;
318 info->poll_max_ns = iothread->poll_max_ns;
319 info->poll_grow = iothread->poll_grow;
320 info->poll_shrink = iothread->poll_shrink;
321
322 elem = g_new0(IOThreadInfoList, 1);
323 elem->value = info;
324 elem->next = NULL;
325
326 **prev = elem;
327 *prev = &elem->next;
328 return 0;
329}
330
331IOThreadInfoList *qmp_query_iothreads(Error **errp)
332{
333 IOThreadInfoList *head = NULL;
334 IOThreadInfoList **prev = &head;
335 Object *container = object_get_objects_root();
336
337 object_child_foreach(container, query_one_iothread, &prev);
338 return head;
339}
340
341static gpointer iothread_g_main_context_init(gpointer opaque)
342{
343 AioContext *ctx;
344 IOThread *iothread = opaque;
345 GSource *source;
346
347 iothread->worker_context = g_main_context_new();
348
349 ctx = iothread_get_aio_context(iothread);
350 source = aio_get_g_source(ctx);
351 g_source_attach(source, iothread->worker_context);
352 g_source_unref(source);
353
354 aio_notify(iothread->ctx);
355 return NULL;
356}
357
358GMainContext *iothread_get_g_main_context(IOThread *iothread)
359{
360 g_once(&iothread->once, iothread_g_main_context_init, iothread);
361
362 return iothread->worker_context;
363}
364
365IOThread *iothread_create(const char *id, Error **errp)
366{
367 Object *obj;
368
369 obj = object_new_with_props(TYPE_IOTHREAD,
370 object_get_internal_root(),
371 id, errp, NULL);
372
373 return IOTHREAD(obj);
374}
375
376void iothread_destroy(IOThread *iothread)
377{
378 object_unparent(OBJECT(iothread));
379}
380
381
382
383IOThread *iothread_by_id(const char *id)
384{
385 return IOTHREAD(object_resolve_path_type(id, TYPE_IOTHREAD, NULL));
386}
387