v4.19.13 snapshot.
diff --git a/tools/perf/bench/futex-lock-pi.c b/tools/perf/bench/futex-lock-pi.c
new file mode 100644
index 0000000..8e9c475
--- /dev/null
+++ b/tools/perf/bench/futex-lock-pi.c
@@ -0,0 +1,230 @@
+// 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 <errno.h>
+#include "bench.h"
+#include "futex.h"
+#include "cpumap.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;
+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 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) 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;
+ 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 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 cpu_map *cpu;
+
+ argc = parse_options(argc, argv, options, bench_futex_lock_pi_usage, 0);
+ if (argc)
+ goto err;
+
+ cpu = 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(&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/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);
+}