| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * Copyright (C) 2015 Davidlohr Bueso. |
| */ |
| |
| /* For the CLR_() macros */ |
| #include <string.h> |
| #include <pthread.h> |
| |
| #include <signal.h> |
| #include "../util/stat.h" |
| #include <subcmd/parse-options.h> |
| #include <linux/compiler.h> |
| #include <linux/kernel.h> |
| #include <linux/zalloc.h> |
| #include <errno.h> |
| #include <internal/cpumap.h> |
| #include <perf/cpumap.h> |
| #include "bench.h" |
| #include "futex.h" |
| |
| #include <err.h> |
| #include <stdlib.h> |
| #include <sys/time.h> |
| |
| struct worker { |
| int tid; |
| u_int32_t *futex; |
| pthread_t thread; |
| unsigned long ops; |
| }; |
| |
| static u_int32_t global_futex = 0; |
| static struct worker *worker; |
| static unsigned int nsecs = 10; |
| static bool silent = false, multi = false; |
| static bool done = false, fshared = false; |
| static unsigned int nthreads = 0; |
| static int futex_flag = 0; |
| static pthread_mutex_t thread_lock; |
| static unsigned int threads_starting; |
| static struct stats throughput_stats; |
| static pthread_cond_t thread_parent, thread_worker; |
| |
| static const struct option options[] = { |
| OPT_UINTEGER('t', "threads", &nthreads, "Specify amount of threads"), |
| OPT_UINTEGER('r', "runtime", &nsecs, "Specify runtime (in seconds)"), |
| OPT_BOOLEAN( 'M', "multi", &multi, "Use multiple futexes"), |
| OPT_BOOLEAN( 's', "silent", &silent, "Silent mode: do not display data/details"), |
| OPT_BOOLEAN( 'S', "shared", &fshared, "Use shared futexes instead of private ones"), |
| OPT_END() |
| }; |
| |
| static const char * const bench_futex_lock_pi_usage[] = { |
| "perf bench futex lock-pi <options>", |
| NULL |
| }; |
| |
| static void print_summary(void) |
| { |
| unsigned long avg = avg_stats(&throughput_stats); |
| double stddev = stddev_stats(&throughput_stats); |
| |
| printf("%sAveraged %ld operations/sec (+- %.2f%%), total secs = %d\n", |
| !silent ? "\n" : "", avg, rel_stddev_stats(stddev, avg), |
| (int)bench__runtime.tv_sec); |
| } |
| |
| static void toggle_done(int sig __maybe_unused, |
| siginfo_t *info __maybe_unused, |
| void *uc __maybe_unused) |
| { |
| /* inform all threads that we're done for the day */ |
| done = true; |
| gettimeofday(&bench__end, NULL); |
| timersub(&bench__end, &bench__start, &bench__runtime); |
| } |
| |
| static void *workerfn(void *arg) |
| { |
| struct worker *w = (struct worker *) arg; |
| unsigned long ops = w->ops; |
| |
| pthread_mutex_lock(&thread_lock); |
| threads_starting--; |
| if (!threads_starting) |
| pthread_cond_signal(&thread_parent); |
| pthread_cond_wait(&thread_worker, &thread_lock); |
| pthread_mutex_unlock(&thread_lock); |
| |
| do { |
| int ret; |
| again: |
| ret = futex_lock_pi(w->futex, NULL, futex_flag); |
| |
| if (ret) { /* handle lock acquisition */ |
| if (!silent) |
| warn("thread %d: Could not lock pi-lock for %p (%d)", |
| w->tid, w->futex, ret); |
| if (done) |
| break; |
| |
| goto again; |
| } |
| |
| usleep(1); |
| ret = futex_unlock_pi(w->futex, futex_flag); |
| if (ret && !silent) |
| warn("thread %d: Could not unlock pi-lock for %p (%d)", |
| w->tid, w->futex, ret); |
| ops++; /* account for thread's share of work */ |
| } while (!done); |
| |
| w->ops = ops; |
| return NULL; |
| } |
| |
| static void create_threads(struct worker *w, pthread_attr_t thread_attr, |
| struct perf_cpu_map *cpu) |
| { |
| cpu_set_t cpuset; |
| unsigned int i; |
| |
| threads_starting = nthreads; |
| |
| for (i = 0; i < nthreads; i++) { |
| worker[i].tid = i; |
| |
| if (multi) { |
| worker[i].futex = calloc(1, sizeof(u_int32_t)); |
| if (!worker[i].futex) |
| err(EXIT_FAILURE, "calloc"); |
| } else |
| worker[i].futex = &global_futex; |
| |
| CPU_ZERO(&cpuset); |
| CPU_SET(cpu->map[i % cpu->nr], &cpuset); |
| |
| if (pthread_attr_setaffinity_np(&thread_attr, sizeof(cpu_set_t), &cpuset)) |
| err(EXIT_FAILURE, "pthread_attr_setaffinity_np"); |
| |
| if (pthread_create(&w[i].thread, &thread_attr, workerfn, &worker[i])) |
| err(EXIT_FAILURE, "pthread_create"); |
| } |
| } |
| |
| int bench_futex_lock_pi(int argc, const char **argv) |
| { |
| int ret = 0; |
| unsigned int i; |
| struct sigaction act; |
| pthread_attr_t thread_attr; |
| struct perf_cpu_map *cpu; |
| |
| argc = parse_options(argc, argv, options, bench_futex_lock_pi_usage, 0); |
| if (argc) |
| goto err; |
| |
| cpu = perf_cpu_map__new(NULL); |
| if (!cpu) |
| err(EXIT_FAILURE, "calloc"); |
| |
| sigfillset(&act.sa_mask); |
| act.sa_sigaction = toggle_done; |
| sigaction(SIGINT, &act, NULL); |
| |
| if (!nthreads) |
| nthreads = cpu->nr; |
| |
| worker = calloc(nthreads, sizeof(*worker)); |
| if (!worker) |
| err(EXIT_FAILURE, "calloc"); |
| |
| if (!fshared) |
| futex_flag = FUTEX_PRIVATE_FLAG; |
| |
| printf("Run summary [PID %d]: %d threads doing pi lock/unlock pairing for %d secs.\n\n", |
| getpid(), nthreads, nsecs); |
| |
| init_stats(&throughput_stats); |
| pthread_mutex_init(&thread_lock, NULL); |
| pthread_cond_init(&thread_parent, NULL); |
| pthread_cond_init(&thread_worker, NULL); |
| |
| threads_starting = nthreads; |
| pthread_attr_init(&thread_attr); |
| gettimeofday(&bench__start, NULL); |
| |
| create_threads(worker, thread_attr, cpu); |
| pthread_attr_destroy(&thread_attr); |
| |
| pthread_mutex_lock(&thread_lock); |
| while (threads_starting) |
| pthread_cond_wait(&thread_parent, &thread_lock); |
| pthread_cond_broadcast(&thread_worker); |
| pthread_mutex_unlock(&thread_lock); |
| |
| sleep(nsecs); |
| toggle_done(0, NULL, NULL); |
| |
| for (i = 0; i < nthreads; i++) { |
| ret = pthread_join(worker[i].thread, NULL); |
| if (ret) |
| err(EXIT_FAILURE, "pthread_join"); |
| } |
| |
| /* cleanup & report results */ |
| pthread_cond_destroy(&thread_parent); |
| pthread_cond_destroy(&thread_worker); |
| pthread_mutex_destroy(&thread_lock); |
| |
| for (i = 0; i < nthreads; i++) { |
| unsigned long t = worker[i].ops / bench__runtime.tv_sec; |
| |
| update_stats(&throughput_stats, t); |
| if (!silent) |
| printf("[thread %3d] futex: %p [ %ld ops/sec ]\n", |
| worker[i].tid, worker[i].futex, t); |
| |
| if (multi) |
| zfree(&worker[i].futex); |
| } |
| |
| print_summary(); |
| |
| free(worker); |
| return ret; |
| err: |
| usage_with_options(bench_futex_lock_pi_usage, options); |
| exit(EXIT_FAILURE); |
| } |