// 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/mutex.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 <perf/cpumap.h>
#include "bench.h"
#include "futex.h"
#include <err.h>
#include <stdlib.h>
#include <sys/time.h>
#include <sys/mman.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 bool done =
false;
static int futex_flag = 0;
static struct mutex thread_lock;
static unsigned int threads_starting;
static struct stats throughput_stats;
static struct cond thread_parent, thread_worker;
static struct bench_futex_parameters params = {
.nbuckets = -1,
.runtime = 10,
};
static const struct option options[] = {
OPT_INTEGER(
'b',
"buckets", ¶ms.nbuckets,
"Specify amount of hash buckets"),
OPT_UINTEGER(
't',
"threads", ¶ms.nthreads,
"Specify amount of threads"),
OPT_UINTEGER(
'r',
"runtime", ¶ms.runtime,
"Specify runtime (in seconds)"),
OPT_BOOLEAN(
'M',
"multi", ¶ms.multi,
"Use multiple futexes"),
OPT_BOOLEAN(
's',
"silent", ¶ms.silent,
"Silent mode: do not display data/details"),
OPT_BOOLEAN(
'S',
"shared", ¶ms.fshared,
"Use shared futexes instead of private ones"),
OPT_BOOLEAN(
'm',
"mlockall", ¶ms.mlockall,
"Lock all current and future memory"),
OPT_END()
};
static const char *
const bench_futex_lock_pi_usage[] = {
"perf bench futex lock-pi ",
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",
!params.silent ?
"\n" :
"", avg, rel_stddev_stats(stddev, avg),
(
int)bench__runtime.tv_sec);
futex_print_nbuckets(¶ms);
}
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;
mutex_lock(&thread_lock);
threads_starting--;
if (!threads_starting)
cond_signal(&thread_parent);
cond_wait(&thread_worker, &thread_lock);
mutex_unlock(&thread_lock);
do {
int ret;
again:
ret = futex_lock_pi(w->futex, NULL, futex_flag);
if (ret) {
/* handle lock acquisition */
if (!params.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 && !params.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,
struct perf_cpu_map *cpu)
{
cpu_set_t *cpuset;
unsigned int i;
int nrcpus = cpu__max_cpu().cpu;
size_t size;
threads_starting = params.nthreads;
cpuset = CPU_ALLOC(nrcpus);
BUG_ON(!cpuset);
size = CPU_ALLOC_SIZE(nrcpus);
for (i = 0; i < params.nthreads; i++) {
pthread_attr_t thread_attr;
pthread_attr_init(&thread_attr);
worker[i].tid = i;
if (params.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_S(size, cpuset);
CPU_SET_S(perf_cpu_map__cpu(cpu, i % perf_cpu_map__nr(cpu)).cpu, size, cpuset);
if (pthread_attr_setaffinity_np(&thread_attr, size, cpuset)) {
CPU_FREE(cpuset);
err(EXIT_FAILURE,
"pthread_attr_setaffinity_np");
}
if (pthread_create(&w[i].thread, &thread_attr, workerfn, &worker[i])) {
CPU_FREE(cpuset);
err(EXIT_FAILURE,
"pthread_create");
}
pthread_attr_destroy(&thread_attr);
}
CPU_FREE(cpuset);
}
int bench_futex_lock_pi(
int argc,
const char **argv)
{
int ret = 0;
unsigned int i;
struct sigaction act;
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_online_cpus();
if (!cpu)
err(EXIT_FAILURE,
"calloc");
memset(&act, 0,
sizeof(act));
sigfillset(&act.sa_mask);
act.sa_sigaction = toggle_done;
sigaction(SIGINT, &act, NULL);
if (params.mlockall) {
if (mlockall(MCL_CURRENT | MCL_FUTURE))
err(EXIT_FAILURE,
"mlockall");
}
if (!params.nthreads)
params.nthreads = perf_cpu_map__nr(cpu);
worker = calloc(params.nthreads,
sizeof(*worker));
if (!worker)
err(EXIT_FAILURE,
"calloc");
if (!params.fshared)
futex_flag = FUTEX_PRIVATE_FLAG;
printf(
"Run summary [PID %d]: %d threads doing pi lock/unlock pairing for %d secs.\n\n",
getpid(), params.nthreads, params.runtime);
init_stats(&throughput_stats);
mutex_init(&thread_lock);
cond_init(&thread_parent);
cond_init(&thread_worker);
futex_set_nbuckets_param(¶ms);
threads_starting = params.nthreads;
gettimeofday(&bench__start, NULL);
create_threads(worker, cpu);
mutex_lock(&thread_lock);
while (threads_starting)
cond_wait(&thread_parent, &thread_lock);
cond_broadcast(&thread_worker);
mutex_unlock(&thread_lock);
sleep(params.runtime);
toggle_done(0, NULL, NULL);
for (i = 0; i < params.nthreads; i++) {
ret = pthread_join(worker[i].thread, NULL);
if (ret)
err(EXIT_FAILURE,
"pthread_join");
}
/* cleanup & report results */
cond_destroy(&thread_parent);
cond_destroy(&thread_worker);
mutex_destroy(&thread_lock);
for (i = 0; i < params.nthreads; i++) {
unsigned long t = bench__runtime.tv_sec > 0 ?
worker[i].ops / bench__runtime.tv_sec : 0;
update_stats(&throughput_stats, t);
if (!params.silent)
printf(
"[thread %3d] futex: %p [ %ld ops/sec ]\n",
worker[i].tid, worker[i].futex, t);
if (params.multi)
zfree(&worker[i].futex);
}
print_summary();
free(worker);
perf_cpu_map__put(cpu);
return ret;
err:
usage_with_options(bench_futex_lock_pi_usage, options);
exit(EXIT_FAILURE);
}
