diff --git a/tools/perf/bench/numa.c b/tools/perf/bench/numa.c index f85bceccc459..11726ec6285f 100644 --- a/tools/perf/bench/numa.c +++ b/tools/perf/bench/numa.c @@ -137,12 +137,13 @@ struct global_info { u8 *data; pthread_mutex_t startup_mutex; + pthread_cond_t startup_cond; int nr_tasks_started; - pthread_mutex_t startup_done_mutex; - pthread_mutex_t start_work_mutex; + pthread_cond_t start_work_cond; int nr_tasks_working; + bool start_work; pthread_mutex_t stop_work_mutex; u64 bytes_done; @@ -483,6 +484,18 @@ static void init_global_mutex(pthread_mutex_t *mutex) pthread_mutex_init(mutex, &attr); } +/* + * Return a process-shared (global) condition variable: + */ +static void init_global_cond(pthread_cond_t *cond) +{ + pthread_condattr_t attr; + + pthread_condattr_init(&attr); + pthread_condattr_setpshared(&attr, PTHREAD_PROCESS_SHARED); + pthread_cond_init(cond, &attr); +} + static int parse_cpu_list(const char *arg) { p0.cpu_list_str = strdup(arg); @@ -1136,15 +1149,18 @@ static void *worker_thread(void *__tdata) if (g->p.serialize_startup) { pthread_mutex_lock(&g->startup_mutex); g->nr_tasks_started++; + /* The last thread wakes the main process. */ + if (g->nr_tasks_started == g->p.nr_tasks) + pthread_cond_signal(&g->startup_cond); + pthread_mutex_unlock(&g->startup_mutex); /* Here we will wait for the main process to start us all at once: */ pthread_mutex_lock(&g->start_work_mutex); + g->start_work = false; g->nr_tasks_working++; - - /* Last one wake the main process: */ - if (g->nr_tasks_working == g->p.nr_tasks) - pthread_mutex_unlock(&g->startup_done_mutex); + while (!g->start_work) + pthread_cond_wait(&g->start_work_cond, &g->start_work_mutex); pthread_mutex_unlock(&g->start_work_mutex); } @@ -1441,8 +1457,9 @@ static int init(void) /* Startup serialization: */ init_global_mutex(&g->start_work_mutex); + init_global_cond(&g->start_work_cond); init_global_mutex(&g->startup_mutex); - init_global_mutex(&g->startup_done_mutex); + init_global_cond(&g->startup_cond); init_global_mutex(&g->stop_work_mutex); init_thread_data(); @@ -1502,9 +1519,6 @@ static int __bench_numa(const char *name) pids = zalloc(g->p.nr_proc * sizeof(*pids)); pid = -1; - /* All threads try to acquire it, this way we can wait for them to start up: */ - pthread_mutex_lock(&g->start_work_mutex); - if (g->p.serialize_startup) { tprintf(" #\n"); tprintf(" # Startup synchronization: ..."); fflush(stdout); @@ -1526,22 +1540,29 @@ static int __bench_numa(const char *name) pids[i] = pid; } - /* Wait for all the threads to start up: */ - while (g->nr_tasks_started != g->p.nr_tasks) - usleep(USEC_PER_MSEC); - - BUG_ON(g->nr_tasks_started != g->p.nr_tasks); if (g->p.serialize_startup) { + bool threads_ready = false; double startup_sec; - pthread_mutex_lock(&g->startup_done_mutex); + /* + * Wait for all the threads to start up. The last thread will + * signal this process. + */ + pthread_mutex_lock(&g->startup_mutex); + while (g->nr_tasks_started != g->p.nr_tasks) + pthread_cond_wait(&g->startup_cond, &g->startup_mutex); - /* This will start all threads: */ - pthread_mutex_unlock(&g->start_work_mutex); + pthread_mutex_unlock(&g->startup_mutex); - /* This mutex is locked - the last started thread will wake us: */ - pthread_mutex_lock(&g->startup_done_mutex); + /* Wait for all threads to be at the start_work_cond. */ + while (!threads_ready) { + pthread_mutex_lock(&g->start_work_mutex); + threads_ready = (g->nr_tasks_working == g->p.nr_tasks); + pthread_mutex_unlock(&g->start_work_mutex); + if (!threads_ready) + usleep(1); + } gettimeofday(&stop, NULL); @@ -1555,7 +1576,11 @@ static int __bench_numa(const char *name) tprintf(" #\n"); start = stop; - pthread_mutex_unlock(&g->startup_done_mutex); + /* Start all threads running. */ + pthread_mutex_lock(&g->start_work_mutex); + g->start_work = true; + pthread_mutex_unlock(&g->start_work_mutex); + pthread_cond_broadcast(&g->start_work_cond); } else { gettimeofday(&start, NULL); }