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