diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /tools/perf/bench/futex-hash.c | |
parent | Initial commit. (diff) | |
download | linux-upstream.tar.xz linux-upstream.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'tools/perf/bench/futex-hash.c')
-rw-r--r-- | tools/perf/bench/futex-hash.c | 251 |
1 files changed, 251 insertions, 0 deletions
diff --git a/tools/perf/bench/futex-hash.c b/tools/perf/bench/futex-hash.c new file mode 100644 index 000000000..2005a3fa3 --- /dev/null +++ b/tools/perf/bench/futex-hash.c @@ -0,0 +1,251 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2013 Davidlohr Bueso <davidlohr@hp.com> + * + * futex-hash: Stress the hell out of the Linux kernel futex uaddr hashing. + * + * This program is particularly useful for measuring the kernel's futex hash + * table/function implementation. In order for it to make sense, use with as + * many threads and futexes as possible. + */ + +/* For the CLR_() macros */ +#include <string.h> +#include <pthread.h> + +#include <errno.h> +#include <signal.h> +#include <stdlib.h> +#include <linux/compiler.h> +#include <linux/kernel.h> +#include <linux/zalloc.h> +#include <sys/time.h> +#include <sys/mman.h> +#include <perf/cpumap.h> + +#include "../util/mutex.h" +#include "../util/stat.h" +#include <subcmd/parse-options.h> +#include "bench.h" +#include "futex.h" + +#include <err.h> + +static bool done = false; +static int futex_flag = 0; + +struct timeval bench__start, bench__end, bench__runtime; +static struct mutex thread_lock; +static unsigned int threads_starting; +static struct stats throughput_stats; +static struct cond thread_parent, thread_worker; + +struct worker { + int tid; + u_int32_t *futex; + pthread_t thread; + unsigned long ops; +}; + +static struct bench_futex_parameters params = { + .nfutexes = 1024, + .runtime = 10, +}; + +static const struct option options[] = { + OPT_UINTEGER('t', "threads", ¶ms.nthreads, "Specify amount of threads"), + OPT_UINTEGER('r', "runtime", ¶ms.runtime, "Specify runtime (in seconds)"), + OPT_UINTEGER('f', "futexes", ¶ms.nfutexes, "Specify amount of futexes per threads"), + 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_hash_usage[] = { + "perf bench futex hash <options>", + NULL +}; + +static void *workerfn(void *arg) +{ + int ret; + struct worker *w = (struct worker *) arg; + unsigned int i; + unsigned long ops = w->ops; /* avoid cacheline bouncing */ + + mutex_lock(&thread_lock); + threads_starting--; + if (!threads_starting) + cond_signal(&thread_parent); + cond_wait(&thread_worker, &thread_lock); + mutex_unlock(&thread_lock); + + do { + for (i = 0; i < params.nfutexes; i++, ops++) { + /* + * We want the futex calls to fail in order to stress + * the hashing of uaddr and not measure other steps, + * such as internal waitqueue handling, thus enlarging + * the critical region protected by hb->lock. + */ + ret = futex_wait(&w->futex[i], 1234, NULL, futex_flag); + if (!params.silent && + (!ret || errno != EAGAIN || errno != EWOULDBLOCK)) + warn("Non-expected futex return call"); + } + } while (!done); + + w->ops = ops; + return NULL; +} + +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 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); +} + +int bench_futex_hash(int argc, const char **argv) +{ + int ret = 0; + cpu_set_t *cpuset; + struct sigaction act; + unsigned int i; + pthread_attr_t thread_attr; + struct worker *worker = NULL; + struct perf_cpu_map *cpu; + int nrcpus; + size_t size; + + argc = parse_options(argc, argv, options, bench_futex_hash_usage, 0); + if (argc) { + usage_with_options(bench_futex_hash_usage, options); + exit(EXIT_FAILURE); + } + + cpu = perf_cpu_map__new(NULL); + if (!cpu) + goto errmem; + + 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) /* default to the number of CPUs */ + params.nthreads = perf_cpu_map__nr(cpu); + + worker = calloc(params.nthreads, sizeof(*worker)); + if (!worker) + goto errmem; + + if (!params.fshared) + futex_flag = FUTEX_PRIVATE_FLAG; + + printf("Run summary [PID %d]: %d threads, each operating on %d [%s] futexes for %d secs.\n\n", + getpid(), params.nthreads, params.nfutexes, params.fshared ? "shared":"private", params.runtime); + + init_stats(&throughput_stats); + mutex_init(&thread_lock); + cond_init(&thread_parent); + cond_init(&thread_worker); + + threads_starting = params.nthreads; + pthread_attr_init(&thread_attr); + gettimeofday(&bench__start, NULL); + + nrcpus = perf_cpu_map__nr(cpu); + cpuset = CPU_ALLOC(nrcpus); + BUG_ON(!cpuset); + size = CPU_ALLOC_SIZE(nrcpus); + + for (i = 0; i < params.nthreads; i++) { + worker[i].tid = i; + worker[i].futex = calloc(params.nfutexes, sizeof(*worker[i].futex)); + if (!worker[i].futex) + goto errmem; + + CPU_ZERO_S(size, cpuset); + + CPU_SET_S(perf_cpu_map__cpu(cpu, i % perf_cpu_map__nr(cpu)).cpu, size, cpuset); + ret = pthread_attr_setaffinity_np(&thread_attr, size, cpuset); + if (ret) { + CPU_FREE(cpuset); + err(EXIT_FAILURE, "pthread_attr_setaffinity_np"); + } + ret = pthread_create(&worker[i].thread, &thread_attr, workerfn, + (void *)(struct worker *) &worker[i]); + if (ret) { + CPU_FREE(cpuset); + err(EXIT_FAILURE, "pthread_create"); + } + + } + CPU_FREE(cpuset); + pthread_attr_destroy(&thread_attr); + + 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) { + if (params.nfutexes == 1) + printf("[thread %2d] futex: %p [ %ld ops/sec ]\n", + worker[i].tid, &worker[i].futex[0], t); + else + printf("[thread %2d] futexes: %p ... %p [ %ld ops/sec ]\n", + worker[i].tid, &worker[i].futex[0], + &worker[i].futex[params.nfutexes-1], t); + } + + zfree(&worker[i].futex); + } + + print_summary(); + + free(worker); + free(cpu); + return ret; +errmem: + err(EXIT_FAILURE, "calloc"); +} |