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21#include "qemu/osdep.h"
22#include <glib.h>
23#include "qemu-common.h"
24#include "qemu/coroutine_int.h"
25
26typedef struct {
27 Coroutine base;
28 GThread *thread;
29 bool runnable;
30 bool free_on_thread_exit;
31 CoroutineAction action;
32} CoroutineGThread;
33
34static CompatGMutex coroutine_lock;
35static CompatGCond coroutine_cond;
36
37
38
39
40
41#if GLIB_CHECK_VERSION(2, 31, 0)
42
43
44
45
46
47
48static void coroutine_destroy_notify(gpointer data)
49{
50 CoroutineGThread *co = data;
51 if (co && co->free_on_thread_exit) {
52 g_free(co);
53 }
54}
55
56static GPrivate coroutine_key = G_PRIVATE_INIT(coroutine_destroy_notify);
57
58static inline CoroutineGThread *get_coroutine_key(void)
59{
60 return g_private_get(&coroutine_key);
61}
62
63static inline void set_coroutine_key(CoroutineGThread *co,
64 bool free_on_thread_exit)
65{
66
67
68
69
70 co->free_on_thread_exit = free_on_thread_exit;
71 g_private_replace(&coroutine_key, co);
72}
73
74static inline GThread *create_thread(GThreadFunc func, gpointer data)
75{
76 return g_thread_new("coroutine", func, data);
77}
78
79#else
80
81
82
83static GStaticPrivate coroutine_key = G_STATIC_PRIVATE_INIT;
84
85static inline CoroutineGThread *get_coroutine_key(void)
86{
87 return g_static_private_get(&coroutine_key);
88}
89
90static inline void set_coroutine_key(CoroutineGThread *co,
91 bool free_on_thread_exit)
92{
93 g_static_private_set(&coroutine_key, co,
94 free_on_thread_exit ? (GDestroyNotify)g_free : NULL);
95}
96
97static inline GThread *create_thread(GThreadFunc func, gpointer data)
98{
99 return g_thread_create_full(func, data, 0, TRUE, TRUE,
100 G_THREAD_PRIORITY_NORMAL, NULL);
101}
102
103#endif
104
105
106static void __attribute__((constructor)) coroutine_init(void)
107{
108#if !GLIB_CHECK_VERSION(2, 31, 0)
109 if (!g_thread_supported()) {
110 g_thread_init(NULL);
111 }
112#endif
113}
114
115static void coroutine_wait_runnable_locked(CoroutineGThread *co)
116{
117 while (!co->runnable) {
118 g_cond_wait(&coroutine_cond, &coroutine_lock);
119 }
120}
121
122static void coroutine_wait_runnable(CoroutineGThread *co)
123{
124 g_mutex_lock(&coroutine_lock);
125 coroutine_wait_runnable_locked(co);
126 g_mutex_unlock(&coroutine_lock);
127}
128
129static gpointer coroutine_thread(gpointer opaque)
130{
131 CoroutineGThread *co = opaque;
132
133 set_coroutine_key(co, false);
134 coroutine_wait_runnable(co);
135 co->base.entry(co->base.entry_arg);
136 qemu_coroutine_switch(&co->base, co->base.caller, COROUTINE_TERMINATE);
137 return NULL;
138}
139
140Coroutine *qemu_coroutine_new(void)
141{
142 CoroutineGThread *co;
143
144 co = g_malloc0(sizeof(*co));
145 co->thread = create_thread(coroutine_thread, co);
146 if (!co->thread) {
147 g_free(co);
148 return NULL;
149 }
150 return &co->base;
151}
152
153void qemu_coroutine_delete(Coroutine *co_)
154{
155 CoroutineGThread *co = DO_UPCAST(CoroutineGThread, base, co_);
156
157 g_thread_join(co->thread);
158 g_free(co);
159}
160
161CoroutineAction qemu_coroutine_switch(Coroutine *from_,
162 Coroutine *to_,
163 CoroutineAction action)
164{
165 CoroutineGThread *from = DO_UPCAST(CoroutineGThread, base, from_);
166 CoroutineGThread *to = DO_UPCAST(CoroutineGThread, base, to_);
167
168 g_mutex_lock(&coroutine_lock);
169 from->runnable = false;
170 from->action = action;
171 to->runnable = true;
172 to->action = action;
173 g_cond_broadcast(&coroutine_cond);
174
175 if (action != COROUTINE_TERMINATE) {
176 coroutine_wait_runnable_locked(from);
177 }
178 g_mutex_unlock(&coroutine_lock);
179 return from->action;
180}
181
182Coroutine *qemu_coroutine_self(void)
183{
184 CoroutineGThread *co = get_coroutine_key();
185 if (!co) {
186 co = g_malloc0(sizeof(*co));
187 co->runnable = true;
188 set_coroutine_key(co, true);
189 }
190
191 return &co->base;
192}
193
194bool qemu_in_coroutine(void)
195{
196 CoroutineGThread *co = get_coroutine_key();
197
198 return co && co->base.caller;
199}
200