1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134 | #include <pthread.h>
#include <semaphore.h>
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <unistd.h>
// thread shared data
typedef struct
{
size_t thread_count;
size_t data_size;
double* data;
size_t rounds;
unsigned producer_max_delay; // milliseconds
unsigned consumer_max_delay; // milliseconds
sem_t producer_semaphore;
sem_t consumer_semaphore;
pthread_mutex_t stdout_mutex;
} shared_data_t;
void* produce(void* data)
{
shared_data_t* shared_data = (shared_data_t*)data;
for ( size_t round = 1; round <= shared_data->rounds; ++round )
{
for ( size_t index = 0; index < shared_data->data_size; ++index )
{
sem_wait( &shared_data->producer_semaphore );
// Producer requires time to produce a value
usleep( rand() % (shared_data->producer_max_delay + 1) * 1000 );
double product = round + (index + 1) / 100.0;
shared_data->data[index] = product;
pthread_mutex_lock( &shared_data->stdout_mutex );
printf("Produced %.2f\n", product);
pthread_mutex_unlock( &shared_data->stdout_mutex );
sem_post( &shared_data->consumer_semaphore );
}
}
return NULL;
}
void* consume(void* data)
{
shared_data_t* shared_data = (shared_data_t*)data;
for ( size_t round = 1; round <= shared_data->rounds; ++round )
{
for ( size_t index = 0; index < shared_data->data_size; ++index )
{
sem_wait( &shared_data->consumer_semaphore );
// Consumer requires time to consume a value
usleep( rand() % (shared_data->consumer_max_delay + 1) * 1000 );
double product = shared_data->data[index];
pthread_mutex_lock( &shared_data->stdout_mutex );
printf("\t\t\tConsumed %.2f\n", product);
pthread_mutex_unlock( &shared_data->stdout_mutex );
sem_post( &shared_data->producer_semaphore );
}
}
return NULL;
}
int main(int argc, char* argv[])
{
srand( time(NULL) );
shared_data_t shared_data;
shared_data.thread_count = 2;
if ( argc == 5 )
{
if ( sscanf(argv[1], "%zu", &shared_data.data_size) != 1 || shared_data.data_size == 0 )
return (void)fprintf(stderr, "producer_consumer: error: invalid data size: %s\n", argv[1]), 1;
if ( sscanf(argv[2], "%zu", &shared_data.rounds) != 1 || shared_data.rounds == 0 )
return (void)fprintf(stderr, "producer_consumer: error: invalid rounds: %s\n", argv[2]), 1;
if ( sscanf(argv[3], "%u", &shared_data.producer_max_delay) != 1 )
return (void)fprintf(stderr, "producer_consumer: error: invalid producer max delay: %s\n", argv[3]), 1;
if ( sscanf(argv[4], "%u", &shared_data.consumer_max_delay) != 1 )
return (void)fprintf(stderr, "producer_consumer: error: invalid consumer max delay: %s\n", argv[4]), 1;
}
else
return (void)fprintf(stderr, "usage: producer_consumer data_size rounds producer_delay consumer_delay\n"), 1;
shared_data.data = (double*) calloc(shared_data.data_size, sizeof(double));
if ( shared_data.data == NULL )
return 6;
sem_init( &shared_data.producer_semaphore, 0, shared_data.data_size );
sem_init( &shared_data.consumer_semaphore, 0, 0);
pthread_mutex_init( &shared_data.stdout_mutex, NULL );
pthread_t* threads = (pthread_t*)malloc(shared_data.thread_count * sizeof(pthread_t));
if ( threads == NULL )
return (void)fprintf(stderr, "hello_w: error: could not allocate memory for: %zu threads\n", shared_data.thread_count), 2;
struct timespec start_time;
clock_gettime(CLOCK_MONOTONIC, &start_time);
// Create producer
pthread_create(&threads[0], NULL, produce, &shared_data);
// Create consumer
pthread_create(&threads[1], NULL, consume, &shared_data);
for ( size_t index = 0; index < shared_data.thread_count; ++index )
pthread_join(threads[index], NULL);
struct timespec finish_time;
clock_gettime(CLOCK_MONOTONIC, &finish_time);
double seconds = finish_time.tv_sec - start_time.tv_sec
+ (finish_time.tv_nsec - start_time.tv_nsec) * 1e-9;
printf("Simulation time: %.9lfs\n", seconds);
pthread_mutex_destroy( &shared_data.stdout_mutex );
sem_destroy(&shared_data.consumer_semaphore);
sem_destroy(&shared_data.producer_semaphore);
free(shared_data.data);
free(threads);
return 0;
}
|