linux_dsm_epyc7002/tools/perf/bench/futex-lock-pi.c
Arnaldo Carvalho de Melo d8f9da2404 perf tools: Use zfree() where applicable
In places where the equivalent was already being done, i.e.:

   free(a);
   a = NULL;

And in placs where struct members are being freed so that if we have
some erroneous reference to its struct, then accesses to freed members
will result in segfaults, which we can detect faster than use after free
to areas that may still have something seemingly valid.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-jatyoofo5boc1bsvoig6bb6i@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-07-09 10:13:27 -03:00

232 lines
5.5 KiB
C

// 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 "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)
zfree(&worker[i].futex);
}
print_summary();
free(worker);
return ret;
err:
usage_with_options(bench_futex_lock_pi_usage, options);
exit(EXIT_FAILURE);
}