diff options
| -rw-r--r-- | tools/perf/Documentation/perf-bench.txt | 3 | ||||
| -rw-r--r-- | tools/perf/bench/Build | 1 | ||||
| -rw-r--r-- | tools/perf/bench/bench.h | 1 | ||||
| -rw-r--r-- | tools/perf/bench/epoll-ctl.c | 413 | ||||
| -rw-r--r-- | tools/perf/builtin-bench.c | 1 |
5 files changed, 419 insertions, 0 deletions
diff --git a/tools/perf/Documentation/perf-bench.txt b/tools/perf/Documentation/perf-bench.txt index 3a6b2e73b2e8..0921a3c67381 100644 --- a/tools/perf/Documentation/perf-bench.txt +++ b/tools/perf/Documentation/perf-bench.txt @@ -211,6 +211,9 @@ SUITES FOR 'epoll' *wait*:: Suite for evaluating concurrent epoll_wait calls. +*ctl*:: +Suite for evaluating multiple epoll_ctl calls. + SEE ALSO -------- linkperf:perf[1] diff --git a/tools/perf/bench/Build b/tools/perf/bench/Build index 2bb79b542d53..e4e321b6f883 100644 --- a/tools/perf/bench/Build +++ b/tools/perf/bench/Build @@ -8,6 +8,7 @@ perf-y += futex-requeue.o perf-y += futex-lock-pi.o perf-y += epoll-wait.o +perf-y += epoll-ctl.o perf-$(CONFIG_X86_64) += mem-memcpy-x86-64-lib.o perf-$(CONFIG_X86_64) += mem-memcpy-x86-64-asm.o diff --git a/tools/perf/bench/bench.h b/tools/perf/bench/bench.h index 6e1f091ced96..fddb3ced9db6 100644 --- a/tools/perf/bench/bench.h +++ b/tools/perf/bench/bench.h @@ -39,6 +39,7 @@ int bench_futex_requeue(int argc, const char **argv); int bench_futex_lock_pi(int argc, const char **argv); int bench_epoll_wait(int argc, const char **argv); +int bench_epoll_ctl(int argc, const char **argv); #define BENCH_FORMAT_DEFAULT_STR "default" #define BENCH_FORMAT_DEFAULT 0 diff --git a/tools/perf/bench/epoll-ctl.c b/tools/perf/bench/epoll-ctl.c new file mode 100644 index 000000000000..0c0a6e824934 --- /dev/null +++ b/tools/perf/bench/epoll-ctl.c @@ -0,0 +1,413 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2018 Davidlohr Bueso. + * + * Benchmark the various operations allowed for epoll_ctl(2). + * The idea is to concurrently stress a single epoll instance + */ +#ifdef HAVE_EVENTFD +/* For the CLR_() macros */ +#include <string.h> +#include <pthread.h> + +#include <errno.h> +#include <inttypes.h> +#include <signal.h> +#include <stdlib.h> +#include <linux/compiler.h> +#include <linux/kernel.h> +#include <sys/time.h> +#include <sys/resource.h> +#include <sys/epoll.h> +#include <sys/eventfd.h> + +#include "../util/stat.h" +#include <subcmd/parse-options.h> +#include "bench.h" +#include "cpumap.h" + +#include <err.h> + +#define printinfo(fmt, arg...) \ + do { if (__verbose) printf(fmt, ## arg); } while (0) + +static unsigned int nthreads = 0; +static unsigned int nsecs = 8; +struct timeval start, end, runtime; +static bool done, __verbose, randomize; + +/* + * epoll related shared variables. + */ + +/* Maximum number of nesting allowed inside epoll sets */ +#define EPOLL_MAXNESTS 4 + +enum { + OP_EPOLL_ADD, + OP_EPOLL_MOD, + OP_EPOLL_DEL, + EPOLL_NR_OPS, +}; + +static int epollfd; +static int *epollfdp; +static bool noaffinity; +static unsigned int nested = 0; + +/* amount of fds to monitor, per thread */ +static unsigned int nfds = 64; + +static pthread_mutex_t thread_lock; +static unsigned int threads_starting; +static struct stats all_stats[EPOLL_NR_OPS]; +static pthread_cond_t thread_parent, thread_worker; + +struct worker { + int tid; + pthread_t thread; + unsigned long ops[EPOLL_NR_OPS]; + int *fdmap; +}; + +static const struct option options[] = { + OPT_UINTEGER('t', "threads", &nthreads, "Specify amount of threads"), + OPT_UINTEGER('r', "runtime", &nsecs, "Specify runtime (in seconds)"), + OPT_UINTEGER('f', "nfds", &nfds, "Specify amount of file descriptors to monitor for each thread"), + OPT_BOOLEAN( 'n', "noaffinity", &noaffinity, "Disables CPU affinity"), + OPT_UINTEGER( 'N', "nested", &nested, "Nesting level epoll hierarchy (default is 0, no nesting)"), + OPT_BOOLEAN( 'R', "randomize", &randomize, "Perform random operations on random fds"), + OPT_BOOLEAN( 'v', "verbose", &__verbose, "Verbose mode"), + OPT_END() +}; + +static const char * const bench_epoll_ctl_usage[] = { + "perf bench epoll ctl <options>", + 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(&end, NULL); + timersub(&end, &start, &runtime); +} + +static void nest_epollfd(void) +{ + unsigned int i; + struct epoll_event ev; + + if (nested > EPOLL_MAXNESTS) + nested = EPOLL_MAXNESTS; + printinfo("Nesting level(s): %d\n", nested); + + epollfdp = calloc(nested, sizeof(int)); + if (!epollfd) + err(EXIT_FAILURE, "calloc"); + + for (i = 0; i < nested; i++) { + epollfdp[i] = epoll_create(1); + if (epollfd < 0) + err(EXIT_FAILURE, "epoll_create"); + } + + ev.events = EPOLLHUP; /* anything */ + ev.data.u64 = i; /* any number */ + + for (i = nested - 1; i; i--) { + if (epoll_ctl(epollfdp[i - 1], EPOLL_CTL_ADD, + epollfdp[i], &ev) < 0) + err(EXIT_FAILURE, "epoll_ctl"); + } + + if (epoll_ctl(epollfd, EPOLL_CTL_ADD, *epollfdp, &ev) < 0) + err(EXIT_FAILURE, "epoll_ctl"); +} + +static inline void do_epoll_op(struct worker *w, int op, int fd) +{ + int error; + struct epoll_event ev; + + ev.events = EPOLLIN; + ev.data.u64 = fd; + + switch (op) { + case OP_EPOLL_ADD: + error = epoll_ctl(epollfd, EPOLL_CTL_ADD, fd, &ev); + break; + case OP_EPOLL_MOD: + ev.events = EPOLLOUT; + error = epoll_ctl(epollfd, EPOLL_CTL_MOD, fd, &ev); + break; + case OP_EPOLL_DEL: + error = epoll_ctl(epollfd, EPOLL_CTL_DEL, fd, NULL); + break; + default: + error = 1; + break; + } + + if (!error) + w->ops[op]++; +} + +static inline void do_random_epoll_op(struct worker *w) +{ + unsigned long rnd1 = random(), rnd2 = random(); + int op, fd; + + fd = w->fdmap[rnd1 % nfds]; + op = rnd2 % EPOLL_NR_OPS; + + do_epoll_op(w, op, fd); +} + +static void *workerfn(void *arg) +{ + unsigned int i; + struct worker *w = (struct worker *) arg; + struct timespec ts = { .tv_sec = 0, + .tv_nsec = 250 }; + + 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); + + /* Let 'em loose */ + do { + /* random */ + if (randomize) { + do_random_epoll_op(w); + } else { + for (i = 0; i < nfds; i++) { + do_epoll_op(w, OP_EPOLL_ADD, w->fdmap[i]); + do_epoll_op(w, OP_EPOLL_MOD, w->fdmap[i]); + do_epoll_op(w, OP_EPOLL_DEL, w->fdmap[i]); + } + } + + nanosleep(&ts, NULL); + } while (!done); + + return NULL; +} + +static void init_fdmaps(struct worker *w, int pct) +{ + unsigned int i; + int inc; + struct epoll_event ev; + + if (!pct) + return; + + inc = 100/pct; + for (i = 0; i < nfds; i+=inc) { + ev.data.fd = w->fdmap[i]; + ev.events = EPOLLIN; + + if (epoll_ctl(epollfd, EPOLL_CTL_ADD, w->fdmap[i], &ev) < 0) + err(EXIT_FAILURE, "epoll_ct"); + } +} + +static int do_threads(struct worker *worker, struct cpu_map *cpu) +{ + pthread_attr_t thread_attr, *attrp = NULL; + cpu_set_t cpuset; + unsigned int i, j; + int ret; + + if (!noaffinity) + pthread_attr_init(&thread_attr); + + for (i = 0; i < nthreads; i++) { + struct worker *w = &worker[i]; + + w->tid = i; + w->fdmap = calloc(nfds, sizeof(int)); + if (!w->fdmap) + return 1; + + for (j = 0; j < nfds; j++) { + w->fdmap[j] = eventfd(0, EFD_NONBLOCK); + if (w->fdmap[j] < 0) + err(EXIT_FAILURE, "eventfd"); + } + + /* + * Lets add 50% of the fdmap to the epoll instance, and + * do it before any threads are started; otherwise there is + * an initial bias of the call failing (mod and del ops). + */ + if (randomize) + init_fdmaps(w, 50); + + if (!noaffinity) { + CPU_ZERO(&cpuset); + CPU_SET(cpu->map[i % cpu->nr], &cpuset); + + ret = pthread_attr_setaffinity_np(&thread_attr, sizeof(cpu_set_t), &cpuset); + if (ret) + err(EXIT_FAILURE, "pthread_attr_setaffinity_np"); + + attrp = &thread_attr; + } + + ret = pthread_create(&w->thread, attrp, workerfn, + (void *)(struct worker *) w); + if (ret) + err(EXIT_FAILURE, "pthread_create"); + } + + if (!noaffinity) + pthread_attr_destroy(&thread_attr); + + return ret; +} + +static void print_summary(void) +{ + int i; + unsigned long avg[EPOLL_NR_OPS]; + double stddev[EPOLL_NR_OPS]; + + for (i = 0; i < EPOLL_NR_OPS; i++) { + avg[i] = avg_stats(&all_stats[i]); + stddev[i] = stddev_stats(&all_stats[i]); + } + + printf("\nAveraged %ld ADD operations (+- %.2f%%)\n", + avg[OP_EPOLL_ADD], rel_stddev_stats(stddev[OP_EPOLL_ADD], + avg[OP_EPOLL_ADD])); + printf("Averaged %ld MOD operations (+- %.2f%%)\n", + avg[OP_EPOLL_MOD], rel_stddev_stats(stddev[OP_EPOLL_MOD], + avg[OP_EPOLL_MOD])); + printf("Averaged %ld DEL operations (+- %.2f%%)\n", + avg[OP_EPOLL_DEL], rel_stddev_stats(stddev[OP_EPOLL_DEL], + avg[OP_EPOLL_DEL])); +} + +int bench_epoll_ctl(int argc, const char **argv) +{ + int j, ret = 0; + struct sigaction act; + struct worker *worker = NULL; + struct cpu_map *cpu; + struct rlimit rl, prevrl; + unsigned int i; + + argc = parse_options(argc, argv, options, bench_epoll_ctl_usage, 0); + if (argc) { + usage_with_options(bench_epoll_ctl_usage, options); + exit(EXIT_FAILURE); + } + + sigfillset(&act.sa_mask); + act.sa_sigaction = toggle_done; + sigaction(SIGINT, &act, NULL); + + cpu = cpu_map__new(NULL); + if (!cpu) + goto errmem; + + /* a single, main epoll instance */ + epollfd = epoll_create(1); + if (epollfd < 0) + err(EXIT_FAILURE, "epoll_create"); + + /* + * Deal with nested epolls, if any. + */ + if (nested) + nest_epollfd(); + + /* default to the number of CPUs */ + if (!nthreads) + nthreads = cpu->nr; + + worker = calloc(nthreads, sizeof(*worker)); + if (!worker) + goto errmem; + + if (getrlimit(RLIMIT_NOFILE, &prevrl)) + err(EXIT_FAILURE, "getrlimit"); + rl.rlim_cur = rl.rlim_max = nfds * nthreads * 2 + 50; + printinfo("Setting RLIMIT_NOFILE rlimit from %" PRIu64 " to: %" PRIu64 "\n", + (uint64_t)prevrl.rlim_max, (uint64_t)rl.rlim_max); + if (setrlimit(RLIMIT_NOFILE, &rl) < 0) + err(EXIT_FAILURE, "setrlimit"); + + printf("Run summary [PID %d]: %d threads doing epoll_ctl ops " + "%d file-descriptors for %d secs.\n\n", + getpid(), nthreads, nfds, nsecs); + + for (i = 0; i < EPOLL_NR_OPS; i++) + init_stats(&all_stats[i]); + + pthread_mutex_init(&thread_lock, NULL); + pthread_cond_init(&thread_parent, NULL); + pthread_cond_init(&thread_worker, NULL); + + threads_starting = nthreads; + + gettimeofday(&start, NULL); + + do_threads(worker, cpu); + + 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); + printinfo("main thread: toggling done\n"); + + 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[EPOLL_NR_OPS]; + + for (j = 0; j < EPOLL_NR_OPS; j++) { + t[j] = worker[i].ops[j]; + update_stats(&all_stats[j], t[j]); + } + + if (nfds == 1) + printf("[thread %2d] fdmap: %p [ add: %04ld; mod: %04ld; del: %04lds ops ]\n", + worker[i].tid, &worker[i].fdmap[0], + t[OP_EPOLL_ADD], t[OP_EPOLL_MOD], t[OP_EPOLL_DEL]); + else + printf("[thread %2d] fdmap: %p ... %p [ add: %04ld ops; mod: %04ld ops; del: %04ld ops ]\n", + worker[i].tid, &worker[i].fdmap[0], + &worker[i].fdmap[nfds-1], + t[OP_EPOLL_ADD], t[OP_EPOLL_MOD], t[OP_EPOLL_DEL]); + } + + print_summary(); + + close(epollfd); + return ret; +errmem: + err(EXIT_FAILURE, "calloc"); +} +#endif // HAVE_EVENTFD diff --git a/tools/perf/builtin-bench.c b/tools/perf/builtin-bench.c index 55efd23c3efb..334c77ffc1d9 100644 --- a/tools/perf/builtin-bench.c +++ b/tools/perf/builtin-bench.c @@ -71,6 +71,7 @@ static struct bench futex_benchmarks[] = { #ifdef HAVE_EVENTFD static struct bench epoll_benchmarks[] = { { "wait", "Benchmark epoll concurrent epoll_waits", bench_epoll_wait }, + { "ctl", "Benchmark epoll concurrent epoll_ctls", bench_epoll_ctl }, { "all", "Run all futex benchmarks", NULL }, { NULL, NULL, NULL } }; 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