diff options
Diffstat (limited to 'tools/perf/bench')
-rw-r--r-- | tools/perf/bench/Build | 1 | ||||
-rw-r--r-- | tools/perf/bench/bench.h | 2 | ||||
-rw-r--r-- | tools/perf/bench/futex-lock-pi.c | 219 | ||||
-rw-r--r-- | tools/perf/bench/futex.h | 20 |
4 files changed, 242 insertions, 0 deletions
diff --git a/tools/perf/bench/Build b/tools/perf/bench/Build index c3ab760e0..573e28896 100644 --- a/tools/perf/bench/Build +++ b/tools/perf/bench/Build @@ -5,6 +5,7 @@ perf-y += futex-hash.o perf-y += futex-wake.o perf-y += futex-wake-parallel.o perf-y += futex-requeue.o +perf-y += futex-lock-pi.o perf-$(CONFIG_X86_64) += mem-memcpy-x86-64-asm.o perf-$(CONFIG_X86_64) += mem-memset-x86-64-asm.o diff --git a/tools/perf/bench/bench.h b/tools/perf/bench/bench.h index 70b2f718c..a50df86f2 100644 --- a/tools/perf/bench/bench.h +++ b/tools/perf/bench/bench.h @@ -36,6 +36,8 @@ extern int bench_futex_wake(int argc, const char **argv, const char *prefix); extern int bench_futex_wake_parallel(int argc, const char **argv, const char *prefix); extern int bench_futex_requeue(int argc, const char **argv, const char *prefix); +/* pi futexes */ +extern int bench_futex_lock_pi(int argc, const char **argv, const char *prefix); #define BENCH_FORMAT_DEFAULT_STR "default" #define BENCH_FORMAT_DEFAULT 0 diff --git a/tools/perf/bench/futex-lock-pi.c b/tools/perf/bench/futex-lock-pi.c new file mode 100644 index 000000000..bc6a16adb --- /dev/null +++ b/tools/perf/bench/futex-lock-pi.c @@ -0,0 +1,219 @@ +/* + * Copyright (C) 2015 Davidlohr Bueso. + */ + +#include "../perf.h" +#include "../util/util.h" +#include "../util/stat.h" +#include "../util/parse-options.h" +#include "../util/header.h" +#include "bench.h" +#include "futex.h" + +#include <err.h> +#include <stdlib.h> +#include <sys/time.h> +#include <pthread.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 ncpus, nthreads = 0; +static int futex_flag = 0; +struct timeval start, end, runtime; +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 requeue <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) 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(&end, NULL); + timersub(&end, &start, &runtime); +} + +static void *workerfn(void *arg) +{ + struct worker *w = (struct worker *) arg; + + 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, 0, 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); + w->ops++; /* account for thread's share of work */ + } while (!done); + + return NULL; +} + +static void create_threads(struct worker *w, pthread_attr_t thread_attr) +{ + cpu_set_t cpu; + 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(&cpu); + CPU_SET(i % ncpus, &cpu); + + if (pthread_attr_setaffinity_np(&thread_attr, sizeof(cpu_set_t), &cpu)) + 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, + const char *prefix __maybe_unused) +{ + int ret = 0; + unsigned int i; + struct sigaction act; + pthread_attr_t thread_attr; + + argc = parse_options(argc, argv, options, bench_futex_lock_pi_usage, 0); + if (argc) + goto err; + + ncpus = sysconf(_SC_NPROCESSORS_ONLN); + + sigfillset(&act.sa_mask); + act.sa_sigaction = toggle_done; + sigaction(SIGINT, &act, NULL); + + if (!nthreads) + nthreads = ncpus; + + 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(&start, NULL); + + create_threads(worker, thread_attr); + 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/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) + free(worker[i].futex); + } + + print_summary(); + + free(worker); + return ret; +err: + usage_with_options(bench_futex_lock_pi_usage, options); + exit(EXIT_FAILURE); +} diff --git a/tools/perf/bench/futex.h b/tools/perf/bench/futex.h index 7ed22ff1e..d44de9f44 100644 --- a/tools/perf/bench/futex.h +++ b/tools/perf/bench/futex.h @@ -56,6 +56,26 @@ futex_wake(u_int32_t *uaddr, int nr_wake, int opflags) } /** + * futex_lock_pi() - block on uaddr as a PI mutex + * @detect: whether (1) or not (0) to perform deadlock detection + */ +static inline int +futex_lock_pi(u_int32_t *uaddr, struct timespec *timeout, int detect, + int opflags) +{ + return futex(uaddr, FUTEX_LOCK_PI, detect, timeout, NULL, 0, opflags); +} + +/** + * futex_unlock_pi() - release uaddr as a PI mutex, waking the top waiter + */ +static inline int +futex_unlock_pi(u_int32_t *uaddr, int opflags) +{ + return futex(uaddr, FUTEX_UNLOCK_PI, 0, NULL, NULL, 0, opflags); +} + +/** * futex_cmp_requeue() - requeue tasks from uaddr to uaddr2 * @nr_wake: wake up to this many tasks * @nr_requeue: requeue up to this many tasks |