| 1 | /* |
| 2 | * test_urcu.c |
| 3 | * |
| 4 | * Userspace RCU library - test program |
| 5 | * |
| 6 | * Copyright February 2009 - Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> |
| 7 | * |
| 8 | * Distributed under GPLv2 |
| 9 | */ |
| 10 | |
| 11 | #include <stdio.h> |
| 12 | #include <pthread.h> |
| 13 | #include <stdlib.h> |
| 14 | #include <string.h> |
| 15 | #include <sys/types.h> |
| 16 | #include <sys/wait.h> |
| 17 | #include <unistd.h> |
| 18 | #include <stdio.h> |
| 19 | #include <assert.h> |
| 20 | #include <sys/syscall.h> |
| 21 | |
| 22 | #if defined(_syscall0) |
| 23 | _syscall0(pid_t, gettid) |
| 24 | #elif defined(__NR_gettid) |
| 25 | static inline pid_t gettid(void) |
| 26 | { |
| 27 | return syscall(__NR_gettid); |
| 28 | } |
| 29 | #else |
| 30 | #warning "use pid as tid" |
| 31 | static inline pid_t gettid(void) |
| 32 | { |
| 33 | return getpid(); |
| 34 | } |
| 35 | #endif |
| 36 | |
| 37 | #include "urcu.h" |
| 38 | |
| 39 | struct test_array { |
| 40 | int a; |
| 41 | }; |
| 42 | |
| 43 | static int no_writer_delay; |
| 44 | |
| 45 | static struct test_array *test_rcu_pointer; |
| 46 | |
| 47 | static unsigned long duration; |
| 48 | static time_t start_time; |
| 49 | static unsigned long __thread duration_interval; |
| 50 | #define DURATION_TEST_DELAY_WRITE 4 |
| 51 | #define DURATION_TEST_DELAY_READ 100 |
| 52 | |
| 53 | /* |
| 54 | * returns 0 if test should end. |
| 55 | */ |
| 56 | static int test_duration_write(void) |
| 57 | { |
| 58 | if (duration_interval++ >= DURATION_TEST_DELAY_WRITE) { |
| 59 | duration_interval = 0; |
| 60 | if (time(NULL) - start_time >= duration) |
| 61 | return 0; |
| 62 | } |
| 63 | return 1; |
| 64 | } |
| 65 | |
| 66 | static int test_duration_read(void) |
| 67 | { |
| 68 | if (duration_interval++ >= DURATION_TEST_DELAY_READ) { |
| 69 | duration_interval = 0; |
| 70 | if (time(NULL) - start_time >= duration) |
| 71 | return 0; |
| 72 | } |
| 73 | return 1; |
| 74 | } |
| 75 | |
| 76 | #define NR_READ 10 |
| 77 | #define NR_WRITE 9 |
| 78 | |
| 79 | static unsigned long long __thread nr_writes; |
| 80 | static unsigned long long __thread nr_reads; |
| 81 | |
| 82 | pthread_mutex_t rcu_copy_mutex = PTHREAD_MUTEX_INITIALIZER; |
| 83 | |
| 84 | void rcu_copy_mutex_lock(void) |
| 85 | { |
| 86 | int ret; |
| 87 | ret = pthread_mutex_lock(&rcu_copy_mutex); |
| 88 | if (ret) { |
| 89 | perror("Error in pthread mutex lock"); |
| 90 | exit(-1); |
| 91 | } |
| 92 | } |
| 93 | |
| 94 | void rcu_copy_mutex_unlock(void) |
| 95 | { |
| 96 | int ret; |
| 97 | |
| 98 | ret = pthread_mutex_unlock(&rcu_copy_mutex); |
| 99 | if (ret) { |
| 100 | perror("Error in pthread mutex unlock"); |
| 101 | exit(-1); |
| 102 | } |
| 103 | } |
| 104 | |
| 105 | /* |
| 106 | * malloc/free are reusing memory areas too quickly, which does not let us |
| 107 | * test races appropriately. Use a large circular array for allocations. |
| 108 | * ARRAY_SIZE is larger than NR_WRITE, which insures we never run over our tail. |
| 109 | */ |
| 110 | #define ARRAY_SIZE (1048576 * NR_WRITE) |
| 111 | #define ARRAY_POISON 0xDEADBEEF |
| 112 | static int array_index; |
| 113 | static struct test_array test_array[ARRAY_SIZE]; |
| 114 | |
| 115 | static struct test_array *test_array_alloc(void) |
| 116 | { |
| 117 | struct test_array *ret; |
| 118 | int index; |
| 119 | |
| 120 | rcu_copy_mutex_lock(); |
| 121 | index = array_index % ARRAY_SIZE; |
| 122 | assert(test_array[index].a == ARRAY_POISON || |
| 123 | test_array[index].a == 0); |
| 124 | ret = &test_array[index]; |
| 125 | array_index++; |
| 126 | if (array_index == ARRAY_SIZE) |
| 127 | array_index = 0; |
| 128 | rcu_copy_mutex_unlock(); |
| 129 | return ret; |
| 130 | } |
| 131 | |
| 132 | static void test_array_free(struct test_array *ptr) |
| 133 | { |
| 134 | if (!ptr) |
| 135 | return; |
| 136 | rcu_copy_mutex_lock(); |
| 137 | ptr->a = ARRAY_POISON; |
| 138 | rcu_copy_mutex_unlock(); |
| 139 | } |
| 140 | |
| 141 | void *thr_reader(void *_count) |
| 142 | { |
| 143 | unsigned long long *count = _count; |
| 144 | struct test_array *local_ptr; |
| 145 | |
| 146 | printf("thread_begin %s, thread id : %lx, tid %lu\n", |
| 147 | "reader", pthread_self(), (unsigned long)gettid()); |
| 148 | |
| 149 | urcu_register_thread(); |
| 150 | |
| 151 | for (;;) { |
| 152 | rcu_read_lock(); |
| 153 | local_ptr = rcu_dereference(test_rcu_pointer); |
| 154 | debug_yield_read(); |
| 155 | if (local_ptr) |
| 156 | assert(local_ptr->a == 8); |
| 157 | rcu_read_unlock(); |
| 158 | nr_reads++; |
| 159 | if (!test_duration_read()) |
| 160 | break; |
| 161 | } |
| 162 | |
| 163 | urcu_unregister_thread(); |
| 164 | |
| 165 | *count = nr_reads; |
| 166 | printf("thread_end %s, thread id : %lx, tid %lu\n", |
| 167 | "reader", pthread_self(), (unsigned long)gettid()); |
| 168 | return ((void*)1); |
| 169 | |
| 170 | } |
| 171 | |
| 172 | void *thr_writer(void *_count) |
| 173 | { |
| 174 | unsigned long long *count = _count; |
| 175 | struct test_array *new, *old; |
| 176 | |
| 177 | printf("thread_begin %s, thread id : %lx, tid %lu\n", |
| 178 | "writer", pthread_self(), (unsigned long)gettid()); |
| 179 | |
| 180 | for (;;) { |
| 181 | new = test_array_alloc(); |
| 182 | rcu_copy_mutex_lock(); |
| 183 | old = test_rcu_pointer; |
| 184 | if (old) |
| 185 | assert(old->a == 8); |
| 186 | new->a = 8; |
| 187 | old = urcu_publish_content(&test_rcu_pointer, new); |
| 188 | rcu_copy_mutex_unlock(); |
| 189 | /* can be done after unlock */ |
| 190 | if (old) |
| 191 | old->a = 0; |
| 192 | test_array_free(old); |
| 193 | nr_writes++; |
| 194 | if (!test_duration_write()) |
| 195 | break; |
| 196 | if (!no_writer_delay) |
| 197 | usleep(1); |
| 198 | } |
| 199 | |
| 200 | printf("thread_end %s, thread id : %lx, tid %lu\n", |
| 201 | "writer", pthread_self(), (unsigned long)gettid()); |
| 202 | *count = nr_writes; |
| 203 | return ((void*)2); |
| 204 | } |
| 205 | |
| 206 | void show_usage(int argc, char **argv) |
| 207 | { |
| 208 | printf("Usage : %s duration (s)", argv[0]); |
| 209 | #ifdef DEBUG_YIELD |
| 210 | printf(" [-r] [-w] (yield reader and/or writer)"); |
| 211 | #endif |
| 212 | printf(" [-n] (disable writer delay)"); |
| 213 | printf("\n"); |
| 214 | } |
| 215 | |
| 216 | int main(int argc, char **argv) |
| 217 | { |
| 218 | int err; |
| 219 | pthread_t tid_reader[NR_READ], tid_writer[NR_WRITE]; |
| 220 | void *tret; |
| 221 | unsigned long long count_reader[NR_READ], count_writer[NR_WRITE]; |
| 222 | unsigned long long tot_reads = 0, tot_writes = 0; |
| 223 | int i; |
| 224 | |
| 225 | if (argc < 2) { |
| 226 | show_usage(argc, argv); |
| 227 | return -1; |
| 228 | } |
| 229 | |
| 230 | err = sscanf(argv[1], "%lu", &duration); |
| 231 | if (err != 1) { |
| 232 | show_usage(argc, argv); |
| 233 | return -1; |
| 234 | } |
| 235 | |
| 236 | for (i = 2; i < argc; i++) { |
| 237 | if (argv[i][0] != '-') |
| 238 | continue; |
| 239 | switch (argv[i][1]) { |
| 240 | #ifdef DEBUG_YIELD |
| 241 | case 'r': |
| 242 | yield_active |= YIELD_READ; |
| 243 | break; |
| 244 | case 'w': |
| 245 | yield_active |= YIELD_WRITE; |
| 246 | break; |
| 247 | #endif |
| 248 | case 'n': |
| 249 | no_writer_delay = 1; |
| 250 | break; |
| 251 | } |
| 252 | } |
| 253 | |
| 254 | printf("running test for %lu seconds.\n", duration); |
| 255 | start_time = time(NULL); |
| 256 | printf("thread %-6s, thread id : %lx, tid %lu\n", |
| 257 | "main", pthread_self(), (unsigned long)gettid()); |
| 258 | |
| 259 | for (i = 0; i < NR_READ; i++) { |
| 260 | err = pthread_create(&tid_reader[i], NULL, thr_reader, |
| 261 | &count_reader[i]); |
| 262 | if (err != 0) |
| 263 | exit(1); |
| 264 | } |
| 265 | for (i = 0; i < NR_WRITE; i++) { |
| 266 | err = pthread_create(&tid_writer[i], NULL, thr_writer, |
| 267 | &count_writer[i]); |
| 268 | if (err != 0) |
| 269 | exit(1); |
| 270 | } |
| 271 | |
| 272 | for (i = 0; i < NR_READ; i++) { |
| 273 | err = pthread_join(tid_reader[i], &tret); |
| 274 | if (err != 0) |
| 275 | exit(1); |
| 276 | tot_reads += count_reader[i]; |
| 277 | } |
| 278 | for (i = 0; i < NR_WRITE; i++) { |
| 279 | err = pthread_join(tid_writer[i], &tret); |
| 280 | if (err != 0) |
| 281 | exit(1); |
| 282 | tot_writes += count_writer[i]; |
| 283 | } |
| 284 | |
| 285 | printf("total number of reads : %llu, writes %llu\n", tot_reads, |
| 286 | tot_writes); |
| 287 | test_array_free(test_rcu_pointer); |
| 288 | |
| 289 | return 0; |
| 290 | } |