1 // RUN: %libomp-compile && env OMP_MAX_TASK_PRIORITY='2' %libomp-run
2
3 // Test OMP 4.5 task priorities
4 // Higher priority task supposed to be executed before lower priority task.
5
6 #include <stdio.h>
7 #include <omp.h>
8
9 #include "omp_my_sleep.h"
10 // delay(n) - sleep n ms
11 #define delay(n) my_sleep(((double)n)/1000.0)
12
main(void)13 int main ( void ) {
14 int passed;
15 passed = (omp_get_max_task_priority() == 2);
16 printf("Got %d max priority via env\n", omp_get_max_task_priority());
17 if(!passed) {
18 printf( "failed\n" );
19 return 1;
20 }
21 printf("parallel 1 spawns 4 tasks for primary thread to execute\n");
22 #pragma omp parallel num_threads(2)
23 {
24 int th = omp_get_thread_num();
25 if (th == 0) // primary thread
26 {
27 #pragma omp task priority(1)
28 { // middle priority
29 int val, t = omp_get_thread_num();
30 #pragma omp atomic capture
31 val = passed++;
32 printf("P1: val = %d, thread gen %d, thread exe %d\n", val, th, t);
33 delay(10); // sleep 10 ms
34 }
35 #pragma omp task priority(2)
36 { // high priority
37 int val, t = omp_get_thread_num();
38 #pragma omp atomic capture
39 val = passed++;
40 printf("P2: val = %d, thread gen %d, thread exe %d\n", val, th, t);
41 delay(20); // sleep 20 ms
42 }
43 #pragma omp task priority(0)
44 { // low priority specified explicitly
45 int val, t = omp_get_thread_num();
46 #pragma omp atomic capture
47 val = passed++;
48 printf("P0exp: val = %d, thread gen %d, thread exe %d\n", val, th, t);
49 delay(1); // sleep 1 ms
50 }
51 #pragma omp task
52 { // low priority by default
53 int val, t = omp_get_thread_num();
54 #pragma omp atomic capture
55 val = passed++;
56 printf("P0imp: val = %d, thread gen %d, thread exe %d\n", val, th, t);
57 delay(1); // sleep 1 ms
58 }
59 } else {
60 // wait for the primary thread to finish all tasks
61 int wait = 0;
62 do {
63 delay(5);
64 #pragma omp atomic read
65 wait = passed;
66 } while (wait < 5);
67 }
68 }
69 printf("parallel 2 spawns 4 tasks for worker thread to execute\n");
70 #pragma omp parallel num_threads(2)
71 {
72 int th = omp_get_thread_num();
73 if (th == 0) // primary thread
74 {
75 #pragma omp task priority(1)
76 { // middle priority
77 int val, t = omp_get_thread_num();
78 #pragma omp atomic capture
79 val = passed++;
80 printf("P1: val = %d, thread gen %d, thread exe %d\n", val, th, t);
81 delay(10); // sleep 10 ms
82 }
83 #pragma omp task priority(2)
84 { // high priority
85 int val, t = omp_get_thread_num();
86 #pragma omp atomic capture
87 val = passed++;
88 printf("P2: val = %d, thread gen %d, thread exe %d\n", val, th, t);
89 delay(20); // sleep 20 ms
90 }
91 #pragma omp task priority(0)
92 { // low priority specified explicitly
93 int val, t = omp_get_thread_num();
94 #pragma omp atomic capture
95 val = passed++;
96 printf("P0exp: val = %d, thread gen %d, thread exe %d\n", val, th, t);
97 delay(1); // sleep 1 ms
98 }
99 #pragma omp task
100 { // low priority by default
101 int val, t = omp_get_thread_num();
102 #pragma omp atomic capture
103 val = passed++;
104 printf("P0imp: val = %d, thread gen %d, thread exe %d\n", val, th, t);
105 delay(1); // sleep 1 ms
106 }
107 // signal creation of all tasks: passed = 5 + 1 = 6
108 #pragma omp atomic
109 passed++;
110 // wait for completion of all 4 tasks
111 int wait = 0;
112 do {
113 delay(5);
114 #pragma omp atomic read
115 wait = passed;
116 } while (wait < 10); // passed = 6 + 4 = 10
117 } else {
118 // wait for the primary thread to create all tasks
119 int wait = 0;
120 do {
121 delay(5);
122 #pragma omp atomic read
123 wait = passed;
124 } while (wait < 6);
125 // go execute 4 tasks created by primary thread
126 }
127 }
128 if (passed != 10) {
129 printf("failed, passed = %d (should be 10)\n", passed);
130 return 1;
131 }
132 printf("passed\n");
133 return 0;
134 }
135 // CHECK: parallel 1
136 // CHECK-NEXT: P2
137 // CHECK-NEXT: P1
138 // CHECK-NEXT: P0
139 // CHECK-NEXT: P0
140 // CHECK-NEXT: parallel 2
141 // CHECK-NEXT: P2
142 // CHECK-NEXT: P1
143 // CHECK-NEXT: P0
144 // CHECK-NEXT: P0
145 // CHECK: passed
146