diff options
Diffstat (limited to 'tools/perf/bench/sched-pipe.c')
| -rw-r--r-- | tools/perf/bench/sched-pipe.c | 183 |
1 files changed, 183 insertions, 0 deletions
diff --git a/tools/perf/bench/sched-pipe.c b/tools/perf/bench/sched-pipe.c new file mode 100644 index 000000000..a960e7a93 --- /dev/null +++ b/tools/perf/bench/sched-pipe.c @@ -0,0 +1,183 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * + * sched-pipe.c + * + * pipe: Benchmark for pipe() + * + * Based on pipe-test-1m.c by Ingo Molnar <mingo@redhat.com> + * http://people.redhat.com/mingo/cfs-scheduler/tools/pipe-test-1m.c + * Ported to perf by Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> + */ +#include <subcmd/parse-options.h> +#include "bench.h" + +#include <unistd.h> +#include <stdio.h> +#include <stdlib.h> +#include <signal.h> +#include <sys/wait.h> +#include <string.h> +#include <errno.h> +#include <assert.h> +#include <sys/time.h> +#include <sys/types.h> +#include <sys/syscall.h> +#include <linux/time64.h> + +#include <pthread.h> + +struct thread_data { + int nr; + int pipe_read; + int pipe_write; + pthread_t pthread; +}; + +#define LOOPS_DEFAULT 1000000 +static int loops = LOOPS_DEFAULT; + +/* Use processes by default: */ +static bool threaded; + +static const struct option options[] = { + OPT_INTEGER('l', "loop", &loops, "Specify number of loops"), + OPT_BOOLEAN('T', "threaded", &threaded, "Specify threads/process based task setup"), + OPT_END() +}; + +static const char * const bench_sched_pipe_usage[] = { + "perf bench sched pipe <options>", + NULL +}; + +static void *worker_thread(void *__tdata) +{ + struct thread_data *td = __tdata; + int m = 0, i; + int ret; + + for (i = 0; i < loops; i++) { + if (!td->nr) { + ret = read(td->pipe_read, &m, sizeof(int)); + BUG_ON(ret != sizeof(int)); + ret = write(td->pipe_write, &m, sizeof(int)); + BUG_ON(ret != sizeof(int)); + } else { + ret = write(td->pipe_write, &m, sizeof(int)); + BUG_ON(ret != sizeof(int)); + ret = read(td->pipe_read, &m, sizeof(int)); + BUG_ON(ret != sizeof(int)); + } + } + + return NULL; +} + +int bench_sched_pipe(int argc, const char **argv) +{ + struct thread_data threads[2], *td; + int pipe_1[2], pipe_2[2]; + struct timeval start, stop, diff; + unsigned long long result_usec = 0; + int nr_threads = 2; + int t; + + /* + * why does "ret" exist? + * discarding returned value of read(), write() + * causes error in building environment for perf + */ + int __maybe_unused ret, wait_stat; + pid_t pid, retpid __maybe_unused; + + argc = parse_options(argc, argv, options, bench_sched_pipe_usage, 0); + + BUG_ON(pipe(pipe_1)); + BUG_ON(pipe(pipe_2)); + + gettimeofday(&start, NULL); + + for (t = 0; t < nr_threads; t++) { + td = threads + t; + + td->nr = t; + + if (t == 0) { + td->pipe_read = pipe_1[0]; + td->pipe_write = pipe_2[1]; + } else { + td->pipe_write = pipe_1[1]; + td->pipe_read = pipe_2[0]; + } + } + + + if (threaded) { + + for (t = 0; t < nr_threads; t++) { + td = threads + t; + + ret = pthread_create(&td->pthread, NULL, worker_thread, td); + BUG_ON(ret); + } + + for (t = 0; t < nr_threads; t++) { + td = threads + t; + + ret = pthread_join(td->pthread, NULL); + BUG_ON(ret); + } + + } else { + pid = fork(); + assert(pid >= 0); + + if (!pid) { + worker_thread(threads + 0); + exit(0); + } else { + worker_thread(threads + 1); + } + + retpid = waitpid(pid, &wait_stat, 0); + assert((retpid == pid) && WIFEXITED(wait_stat)); + } + + gettimeofday(&stop, NULL); + timersub(&stop, &start, &diff); + + switch (bench_format) { + case BENCH_FORMAT_DEFAULT: + printf("# Executed %d pipe operations between two %s\n\n", + loops, threaded ? "threads" : "processes"); + + result_usec = diff.tv_sec * USEC_PER_SEC; + result_usec += diff.tv_usec; + + printf(" %14s: %lu.%03lu [sec]\n\n", "Total time", + (unsigned long) diff.tv_sec, + (unsigned long) (diff.tv_usec / USEC_PER_MSEC)); + + printf(" %14lf usecs/op\n", + (double)result_usec / (double)loops); + printf(" %14d ops/sec\n", + (int)((double)loops / + ((double)result_usec / (double)USEC_PER_SEC))); + break; + + case BENCH_FORMAT_SIMPLE: + printf("%lu.%03lu\n", + (unsigned long) diff.tv_sec, + (unsigned long) (diff.tv_usec / USEC_PER_MSEC)); + break; + + default: + /* reaching here is something disaster */ + fprintf(stderr, "Unknown format:%d\n", bench_format); + exit(1); + break; + } + + return 0; +} |