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15#include "qemu/osdep.h"
16#include "qapi/error.h"
17#include "block/aio.h"
18#include "qemu/main-loop.h"
19#include "qemu/rcu.h"
20#include "iothread.h"
21
22struct IOThread {
23 AioContext *ctx;
24 GMainContext *worker_context;
25 GMainLoop *main_loop;
26
27 QemuThread thread;
28 QemuMutex init_done_lock;
29 QemuCond init_done_cond;
30 bool stopping;
31};
32
33static __thread IOThread *my_iothread;
34
35AioContext *qemu_get_current_aio_context(void)
36{
37 return my_iothread ? my_iothread->ctx : qemu_get_aio_context();
38}
39
40static void iothread_init_gcontext(IOThread *iothread)
41{
42 GSource *source;
43
44 iothread->worker_context = g_main_context_new();
45 source = aio_get_g_source(iothread_get_aio_context(iothread));
46 g_source_attach(source, iothread->worker_context);
47 g_source_unref(source);
48 iothread->main_loop = g_main_loop_new(iothread->worker_context, TRUE);
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->ctx = aio_context_new(&error_abort);
60
61
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64
65
66 iothread_init_gcontext(iothread);
67
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70
71
72 g_main_context_push_thread_default(iothread->worker_context);
73
74 qemu_cond_signal(&iothread->init_done_cond);
75 qemu_mutex_unlock(&iothread->init_done_lock);
76
77 while (!qatomic_read(&iothread->stopping)) {
78 aio_poll(iothread->ctx, true);
79 }
80
81 g_main_context_pop_thread_default(iothread->worker_context);
82 rcu_unregister_thread();
83 return NULL;
84}
85
86static void iothread_stop_bh(void *opaque)
87{
88 IOThread *iothread = opaque;
89
90 iothread->stopping = true;
91}
92
93void iothread_join(IOThread *iothread)
94{
95 aio_bh_schedule_oneshot(iothread->ctx, iothread_stop_bh, iothread);
96 qemu_thread_join(&iothread->thread);
97 g_main_context_unref(iothread->worker_context);
98 g_main_loop_unref(iothread->main_loop);
99 qemu_cond_destroy(&iothread->init_done_cond);
100 qemu_mutex_destroy(&iothread->init_done_lock);
101 aio_context_unref(iothread->ctx);
102 g_free(iothread);
103}
104
105IOThread *iothread_new(void)
106{
107 IOThread *iothread = g_new0(IOThread, 1);
108
109 qemu_mutex_init(&iothread->init_done_lock);
110 qemu_cond_init(&iothread->init_done_cond);
111 qemu_thread_create(&iothread->thread, NULL, iothread_run,
112 iothread, QEMU_THREAD_JOINABLE);
113
114
115 qemu_mutex_lock(&iothread->init_done_lock);
116 while (iothread->ctx == NULL) {
117 qemu_cond_wait(&iothread->init_done_cond,
118 &iothread->init_done_lock);
119 }
120 qemu_mutex_unlock(&iothread->init_done_lock);
121 return iothread;
122}
123
124AioContext *iothread_get_aio_context(IOThread *iothread)
125{
126 return iothread->ctx;
127}
128