1 #define _GNU_SOURCE 2 #include <errno.h> 3 #include <string.h> 4 #include <pthread.h> 5 #include <stdlib.h> 6 #include <stdio.h> 7 #include <fcntl.h> 8 #include <unistd.h> 9 #include <sys/types.h> 10 #include <sys/syscall.h> 11 #include <sched.h> 12 #include <signal.h> 13 static int loops = 15; // each thread+main will do this amount of loop 14 static int sleepms = 1000; // in each loop, will sleep "sleepms" milliseconds 15 static int burn = 0; // after each sleep, will burn cpu in a tight 'burn' loop 16 static void setup_sigusr_handler(void); // sigusr1 and 2 sigaction setup. 17 18 static pid_t gettid() 19 { 20 #ifdef __NR_gettid 21 return syscall(__NR_gettid); 22 #else 23 return getpid(); 24 #endif 25 } 26 // will be invoked from gdb. 27 static void whoami(char *msg) __attribute__((unused)); 28 static void whoami(char *msg) 29 { 30 fprintf(stderr, "pid %ld Thread %ld %s\n", (long) getpid(), (long) gettid(), 31 msg); 32 fflush(stderr); 33 } 34 35 36 static void do_burn () 37 { 38 int i; 39 int loopnr = 0; 40 // one single line for the below, to ensure interrupt on this line. 41 for (i = 0; i < burn; i++) loopnr++; 42 } 43 44 static int thread_ready = 0; 45 static pthread_cond_t ready = PTHREAD_COND_INITIALIZER; 46 static pthread_mutex_t ready_mutex = PTHREAD_MUTEX_INITIALIZER; 47 static void signal_ready (void) 48 { 49 int rc; 50 rc = pthread_mutex_lock(&ready_mutex); 51 if (rc != 0) 52 fprintf(stderr, "signal_ready lock error %d_n", rc); 53 thread_ready = 1; 54 rc = pthread_cond_signal(&ready); 55 if (rc != 0) 56 fprintf(stderr, "signal_ready signal error %d_n", rc); 57 rc = pthread_mutex_unlock(&ready_mutex); 58 if (rc != 0) 59 fprintf(stderr, "signal_ready unlock error %d_n", rc); 60 } 61 62 struct spec { 63 char *name; 64 int sleep; 65 int burn; 66 int t; 67 }; 68 static struct timeval t[4]; 69 static int nr_sleeper_or_burner = 0; 70 static volatile int report_finished = 1; 71 // set to 0 to have no finish msg (as order is non-deterministic) 72 static void *sleeper_or_burner(void *v) 73 { 74 int i = 0; 75 struct spec* s = (struct spec*)v; 76 int ret; 77 fprintf(stderr, "%s ready to sleep and/or burn\n", s->name); 78 fflush (stderr); 79 signal_ready(); 80 nr_sleeper_or_burner++; 81 82 for (i = 0; i < loops; i++) { 83 if (sleepms > 0 && s->sleep) { 84 t[s->t].tv_sec = sleepms / 1000; 85 t[s->t].tv_usec = (sleepms % 1000) * 1000; 86 ret = select (0, NULL, NULL, NULL, &t[s->t]); 87 /* We only expect a timeout result or EINTR from the above. */ 88 if (ret != 0 && errno != EINTR) 89 perror("unexpected result from select"); 90 } 91 if (burn > 0 && s->burn) 92 do_burn(); 93 } 94 if (report_finished) { 95 fprintf(stderr, "%s finished to sleep and/or burn\n", s->name); 96 fflush (stderr); 97 } 98 return NULL; 99 } 100 101 // wait till a thread signals it is ready 102 static void wait_ready(void) 103 { 104 int rc; 105 rc = pthread_mutex_lock(&ready_mutex); 106 if (rc != 0) 107 fprintf(stderr, "wait_ready lock error %d_n", rc); 108 while (! thread_ready && rc == 0) { 109 rc = pthread_cond_wait(&ready, &ready_mutex); 110 if (rc != 0) 111 fprintf(stderr, "wait_ready wait error %d_n", rc); 112 } 113 thread_ready = 0; 114 rc = pthread_mutex_unlock(&ready_mutex); 115 if (rc != 0) 116 fprintf(stderr, "wait_ready unlock error %d_n", rc); 117 } 118 119 // We will lock ourselves on one single cpu. 120 // This bypasses the unfairness of the Valgrind scheduler 121 // when a multi-cpu machine has enough cpu to run all the 122 // threads wanting to burn cpu. 123 static void setaffinity(void) 124 { 125 #ifdef VGO_linux 126 cpu_set_t single_cpu; 127 CPU_ZERO(&single_cpu); 128 CPU_SET(1, &single_cpu); 129 (void) sched_setaffinity(0, sizeof(single_cpu), &single_cpu); 130 #endif 131 // GDBTD: equivalent for Darwin ? 132 } 133 134 int main (int argc, char *argv[]) 135 { 136 char *threads_spec; 137 pthread_t ebbr, egll, zzzz; 138 struct spec b, l, p, m; 139 char *some_mem __attribute__((unused)) = malloc(100); 140 if (argc > 5 && atoi(argv[5])) setaffinity(); 141 setup_sigusr_handler(); 142 if (argc > 1) 143 loops = atoi(argv[1]); 144 145 if (argc > 2) 146 sleepms = atoi(argv[2]); 147 148 if (argc > 3) 149 burn = atoll(argv[3]); 150 151 if (argc > 4) 152 threads_spec = argv[4]; 153 else 154 threads_spec = "BSBSBSBS"; 155 156 fprintf(stderr, "loops/sleep_ms/burn/threads_spec/affinity: %d %d %d %s %d\n", 157 loops, sleepms, burn, threads_spec, argc > 5 && atoi(argv[5])); 158 fflush(stderr); 159 160 b.name = "Brussels"; 161 b.burn = *threads_spec++ == 'B'; 162 b.sleep = *threads_spec++ == 'S'; 163 b.t = -1; 164 if (b.burn || b.sleep) { 165 b.t = 1; 166 pthread_create(&ebbr, NULL, sleeper_or_burner, &b); 167 wait_ready(); 168 } 169 170 l.name = "London"; 171 l.burn = *threads_spec++ == 'B'; 172 l.sleep = *threads_spec++ == 'S'; 173 l.t = -1; 174 if (l.burn || l.sleep) { 175 l.t = 2; 176 pthread_create(&egll, NULL, sleeper_or_burner, &l); 177 wait_ready(); 178 } 179 180 p.name = "Petaouchnok"; 181 p.burn = *threads_spec++ == 'B'; 182 p.sleep = *threads_spec++ == 'S'; 183 p.t = -1; 184 if (p.burn || p.sleep) { 185 p.t = 3; 186 pthread_create(&zzzz, NULL, sleeper_or_burner, &p); 187 wait_ready(); 188 } 189 190 m.name = "main"; 191 m.burn = *threads_spec++ == 'B'; 192 m.sleep = *threads_spec++ == 'S'; 193 m.t = 0; 194 sleeper_or_burner(&m); 195 196 if (b.t != -1) pthread_join(ebbr, NULL); 197 if (l.t != -1) pthread_join(egll, NULL); 198 if (p.t != -1) pthread_join(zzzz, NULL); 199 200 return 0; 201 } 202 203 static int sigusr1_received = 0; 204 static void sigusr1_handler(int signr) 205 { 206 sigusr1_received++; 207 } 208 static void setup_sigusr_handler(void) 209 { 210 struct sigaction sa; 211 sa.sa_handler = sigusr1_handler; 212 sigemptyset(&sa.sa_mask); 213 sa.sa_flags = 0; 214 215 if (sigaction (SIGUSR1, &sa, NULL) != 0) 216 perror("sigaction SIGUSR1"); 217 218 sa.sa_handler = SIG_IGN; 219 if (sigaction (SIGUSR2, &sa, NULL) != 0) 220 perror("sigaction SIGUSR2"); 221 } 222 223
