1 | #include <stdatomic.h> |
2 | #include <string.h> |
3 | #include <unistd.h> |
4 | #include <dispatch/dispatch.h> |
5 | #include <pthread.h> |
6 | |
7 | atomic_int finished_enqueueing_work = 0; |
8 | atomic_int thread_count = 0; |
9 | |
10 | void |
11 | doing_the_work_1(void *in) |
12 | { |
13 | // This is only counted once because the first job in the queue |
14 | // starves all the others. |
15 | atomic_fetch_add(&thread_count, 1); |
16 | while (1) |
17 | sleep (seconds: 1); |
18 | } |
19 | |
20 | void |
21 | submit_work_1a(void *in) |
22 | { |
23 | dispatch_queue_t *work_performer_1 = (dispatch_queue_t*) in; |
24 | dispatch_async_f (*work_performer_1, NULL, doing_the_work_1); |
25 | dispatch_async_f (*work_performer_1, NULL, doing_the_work_1); |
26 | } |
27 | |
28 | void |
29 | submit_work_1b(void *in) |
30 | { |
31 | dispatch_queue_t *work_performer_1 = (dispatch_queue_t*) in; |
32 | dispatch_async_f (*work_performer_1, NULL, doing_the_work_1); |
33 | dispatch_async_f (*work_performer_1, NULL, doing_the_work_1); |
34 | atomic_fetch_add(&thread_count, 1); |
35 | while (1) |
36 | sleep (seconds: 1); |
37 | } |
38 | |
39 | void |
40 | doing_the_work_2(void *in) |
41 | { |
42 | atomic_fetch_add(&thread_count, 1); |
43 | while (1) |
44 | sleep (seconds: 1); |
45 | } |
46 | |
47 | void |
48 | submit_work_2(void *in) |
49 | { |
50 | dispatch_queue_t *work_performer_2 = (dispatch_queue_t*) in; |
51 | int i = 0; |
52 | while (i++ < 5000) |
53 | { |
54 | dispatch_async_f (*work_performer_2, NULL, doing_the_work_2); |
55 | dispatch_async_f (*work_performer_2, NULL, doing_the_work_2); |
56 | } |
57 | atomic_fetch_add(&finished_enqueueing_work, 1); |
58 | } |
59 | |
60 | |
61 | void |
62 | doing_the_work_3(void *in) |
63 | { |
64 | // This counts four times, since the queue is marked as CONCURRENT. |
65 | atomic_fetch_add(&thread_count, 1); |
66 | while (1) |
67 | sleep (seconds: 1); |
68 | } |
69 | |
70 | void |
71 | submit_work_3(void *in) |
72 | { |
73 | dispatch_queue_t *work_performer_3 = (dispatch_queue_t*) in; |
74 | dispatch_async_f (*work_performer_3, NULL, doing_the_work_3); |
75 | dispatch_async_f (*work_performer_3, NULL, doing_the_work_3); |
76 | dispatch_async_f (*work_performer_3, NULL, doing_the_work_3); |
77 | dispatch_async_f (*work_performer_3, NULL, doing_the_work_3); |
78 | } |
79 | |
80 | |
81 | void |
82 | stopper () |
83 | { |
84 | while (1) |
85 | sleep (seconds: 1); |
86 | } |
87 | |
88 | |
89 | int main (int argc, const char **argv) |
90 | { |
91 | dispatch_queue_t work_submittor_1 = dispatch_queue_create ("com.apple.work_submittor_1" , DISPATCH_QUEUE_SERIAL); |
92 | dispatch_queue_t work_submittor_2 = dispatch_queue_create ("com.apple.work_submittor_and_quit_2" , DISPATCH_QUEUE_SERIAL); |
93 | dispatch_queue_t work_submittor_3 = dispatch_queue_create ("com.apple.work_submittor_3" , DISPATCH_QUEUE_SERIAL); |
94 | |
95 | dispatch_queue_t work_performer_1 = dispatch_queue_create ("com.apple.work_performer_1" , DISPATCH_QUEUE_SERIAL); |
96 | dispatch_queue_t work_performer_2 = dispatch_queue_create ("com.apple.work_performer_2" , DISPATCH_QUEUE_SERIAL); |
97 | |
98 | dispatch_queue_t work_performer_3 = dispatch_queue_create ("com.apple.work_performer_3" , DISPATCH_QUEUE_CONCURRENT); |
99 | |
100 | dispatch_async_f (work_submittor_1, (void*) &work_performer_1, submit_work_1a); |
101 | dispatch_async_f (work_submittor_1, (void*) &work_performer_1, submit_work_1b); |
102 | |
103 | dispatch_async_f (work_submittor_2, (void*) &work_performer_2, submit_work_2); |
104 | |
105 | dispatch_async_f (work_submittor_3, (void*) &work_performer_3, submit_work_3); |
106 | |
107 | |
108 | // Spin up threads with each of the different libdispatch QoS values. |
109 | dispatch_async (dispatch_get_global_queue(QOS_CLASS_USER_INITIATED, 0), ^{ |
110 | pthread_setname_np ("user initiated QoS" ); |
111 | atomic_fetch_add(&thread_count, 1); |
112 | while (1) |
113 | sleep (seconds: 10); |
114 | }); |
115 | dispatch_async (dispatch_get_global_queue(QOS_CLASS_USER_INTERACTIVE, 0), ^{ |
116 | pthread_setname_np ("user interactive QoS" ); |
117 | atomic_fetch_add(&thread_count, 1); |
118 | while (1) |
119 | sleep (seconds: 10); |
120 | }); |
121 | dispatch_async (dispatch_get_global_queue(QOS_CLASS_DEFAULT, 0), ^{ |
122 | pthread_setname_np ("default QoS" ); |
123 | atomic_fetch_add(&thread_count, 1); |
124 | while (1) |
125 | sleep (seconds: 10); |
126 | }); |
127 | dispatch_async (dispatch_get_global_queue(QOS_CLASS_UTILITY, 0), ^{ |
128 | pthread_setname_np ("utility QoS" ); |
129 | atomic_fetch_add(&thread_count, 1); |
130 | while (1) |
131 | sleep (seconds: 10); |
132 | }); |
133 | dispatch_async (dispatch_get_global_queue(QOS_CLASS_BACKGROUND, 0), ^{ |
134 | pthread_setname_np ("background QoS" ); |
135 | atomic_fetch_add(&thread_count, 1); |
136 | while (1) |
137 | sleep (seconds: 10); |
138 | }); |
139 | |
140 | // Unfortunately there is no pthread_barrier on darwin. |
141 | while ((atomic_load(&thread_count) < 12) || (finished_enqueueing_work == 0)) |
142 | sleep (seconds: 1); |
143 | |
144 | stopper (); |
145 | } |
146 | |