sched-messaging.c

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// SPDX-License-Identifier: GPL-2.0
/*
 *
 * sched-messaging.c
 *
 * messaging: Benchmark for scheduler and IPC mechanisms
 *
 * Based on hackbench by Rusty Russell <rusty@rustcorp.com.au>
 * Ported to perf by Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp>
 *
 */

#include "../perf.h"
#include "../util/util.h"
#include <subcmd/parse-options.h>
#include "../builtin.h"
#include "bench.h"

/* Test groups of 20 processes spraying to 20 receivers */
#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/wait.h>
#include <sys/time.h>
#include <poll.h>
#include <limits.h>
#include <err.h>
#include <linux/time64.h>

#define DATASIZE 100

static bool use_pipes = false;
static unsigned int nr_loops = 100;
static bool thread_mode = false;
static unsigned int num_groups = 10;

struct sender_context {
    unsigned int num_fds;
    int ready_out;
    int wakefd;
    int out_fds[0];
};

struct receiver_context {
    unsigned int num_packets;
    int in_fds[2];
    int ready_out;
    int wakefd;
};

static void fdpair(int fds[2])
{
    if (use_pipes) {
        if (pipe(fds) == 0)
            return;
    } else {
        if (socketpair(AF_UNIX, SOCK_STREAM, 0, fds) == 0)
            return;
    }

    err(EXIT_FAILURE, use_pipes ? "pipe()" : "socketpair()");
}

/* Block until we're ready to go */
static void ready(int ready_out, int wakefd)
{
    char dummy;
    struct pollfd pollfd = { .fd = wakefd, .events = POLLIN };

    /* Tell them we're ready. */
    if (write(ready_out, &dummy, 1) != 1)
        err(EXIT_FAILURE, "CLIENT: ready write");

    /* Wait for "GO" signal */
    if (poll(&pollfd, 1, -1) != 1)
        err(EXIT_FAILURE, "poll");
}

/* Sender sprays nr_loops messages down each file descriptor */
static void *sender(struct sender_context *ctx)
{
    char data[DATASIZE];
    unsigned int i, j;

    ready(ctx->ready_out, ctx->wakefd);

    /* Now pump to every receiver. */
    for (i = 0; i < nr_loops; i++) {
        for (j = 0; j < ctx->num_fds; j++) {
            int ret, done = 0;

again:
            ret = write(ctx->out_fds[j], data + done,
                    sizeof(data)-done);
            if (ret < 0)
                err(EXIT_FAILURE, "SENDER: write");
            done += ret;
            if (done < DATASIZE)
                goto again;
        }
    }

    return NULL;
}


/* One receiver per fd */
static void *receiver(struct receiver_context* ctx)
{
    unsigned int i;

    if (!thread_mode)
        close(ctx->in_fds[1]);

    /* Wait for start... */
    ready(ctx->ready_out, ctx->wakefd);

    /* Receive them all */
    for (i = 0; i < ctx->num_packets; i++) {
        char data[DATASIZE];
        int ret, done = 0;

again:
        ret = read(ctx->in_fds[0], data + done, DATASIZE - done);
        if (ret < 0)
            err(EXIT_FAILURE, "SERVER: read");
        done += ret;
        if (done < DATASIZE)
            goto again;
    }

    return NULL;
}

static pthread_t create_worker(void *ctx, void *(*func)(void *))
{
    pthread_attr_t attr;
    pthread_t childid;
    int ret;

    if (!thread_mode) {
        /* process mode */
        /* Fork the receiver. */
        switch (fork()) {
        case -1:
            err(EXIT_FAILURE, "fork()");
            break;
        case 0:
            (*func) (ctx);
            exit(0);
            break;
        default:
            break;
        }

        return (pthread_t)0;
    }

    if (pthread_attr_init(&attr) != 0)
        err(EXIT_FAILURE, "pthread_attr_init:");

#ifndef __ia64__
    if (pthread_attr_setstacksize(&attr, PTHREAD_STACK_MIN) != 0)
        err(EXIT_FAILURE, "pthread_attr_setstacksize");
#endif

    ret = pthread_create(&childid, &attr, func, ctx);
    if (ret != 0)
        err(EXIT_FAILURE, "pthread_create failed");

    return childid;
}

static void reap_worker(pthread_t id)
{
    int proc_status;
    void *thread_status;

    if (!thread_mode) {
        /* process mode */
        wait(&proc_status);
        if (!WIFEXITED(proc_status))
            exit(1);
    } else {
        pthread_join(id, &thread_status);
    }
}

/* One group of senders and receivers */
static unsigned int group(pthread_t *pth,
        unsigned int num_fds,
        int ready_out,
        int wakefd)
{
    unsigned int i;
    struct sender_context *snd_ctx = malloc(sizeof(struct sender_context)
            + num_fds * sizeof(int));

    if (!snd_ctx)
        err(EXIT_FAILURE, "malloc()");

    for (i = 0; i < num_fds; i++) {
        int fds[2];
        struct receiver_context *ctx = malloc(sizeof(*ctx));

        if (!ctx)
            err(EXIT_FAILURE, "malloc()");


        /* Create the pipe between client and server */
        fdpair(fds);

        ctx->num_packets = num_fds * nr_loops;
        ctx->in_fds[0] = fds[0];
        ctx->in_fds[1] = fds[1];
        ctx->ready_out = ready_out;
        ctx->wakefd = wakefd;

        pth[i] = create_worker(ctx, (void *)receiver);

        snd_ctx->out_fds[i] = fds[1];
        if (!thread_mode)
            close(fds[0]);
    }

    /* Now we have all the fds, fork the senders */
    for (i = 0; i < num_fds; i++) {
        snd_ctx->ready_out = ready_out;
        snd_ctx->wakefd = wakefd;
        snd_ctx->num_fds = num_fds;

        pth[num_fds+i] = create_worker(snd_ctx, (void *)sender);
    }

    /* Close the fds we have left */
    if (!thread_mode)
        for (i = 0; i < num_fds; i++)
            close(snd_ctx->out_fds[i]);

    /* Return number of children to reap */
    return num_fds * 2;
}

static const struct option options[] = {
    OPT_BOOLEAN('p', "pipe", &use_pipes,
            "Use pipe() instead of socketpair()"),
    OPT_BOOLEAN('t', "thread", &thread_mode,
            "Be multi thread instead of multi process"),
    OPT_UINTEGER('g', "group", &num_groups, "Specify number of groups"),
    OPT_UINTEGER('l', "nr_loops", &nr_loops, "Specify the number of loops to run (default: 100)"),
    OPT_END()
};

static const char * const bench_sched_message_usage[] = {
    "perf bench sched messaging <options>",
    NULL
};

int bench_sched_messaging(int argc, const char **argv)
{
    unsigned int i, total_children;
    struct timeval start, stop, diff;
    unsigned int num_fds = 20;
    int readyfds[2], wakefds[2];
    char dummy;
    pthread_t *pth_tab;

    argc = parse_options(argc, argv, options,
                 bench_sched_message_usage, 0);

    pth_tab = malloc(num_fds * 2 * num_groups * sizeof(pthread_t));
    if (!pth_tab)
        err(EXIT_FAILURE, "main:malloc()");

    fdpair(readyfds);
    fdpair(wakefds);

    total_children = 0;
    for (i = 0; i < num_groups; i++)
        total_children += group(pth_tab+total_children, num_fds,
                    readyfds[1], wakefds[0]);

    /* Wait for everyone to be ready */
    for (i = 0; i < total_children; i++)
        if (read(readyfds[0], &dummy, 1) != 1)
            err(EXIT_FAILURE, "Reading for readyfds");

    gettimeofday(&start, NULL);

    /* Kick them off */
    if (write(wakefds[1], &dummy, 1) != 1)
        err(EXIT_FAILURE, "Writing to start them");

    /* Reap them all */
    for (i = 0; i < total_children; i++)
        reap_worker(pth_tab[i]);

    gettimeofday(&stop, NULL);

    timersub(&stop, &start, &diff);

    switch (bench_format) {
    case BENCH_FORMAT_DEFAULT:
        printf("# %d sender and receiver %s per group\n",
               num_fds, thread_mode ? "threads" : "processes");
        printf("# %d groups == %d %s run\n\n",
               num_groups, num_groups * 2 * num_fds,
               thread_mode ? "threads" : "processes");
        printf(" %14s: %lu.%03lu [sec]\n", "Total time",
               diff.tv_sec,
               (unsigned long) (diff.tv_usec / USEC_PER_MSEC));
        break;
    case BENCH_FORMAT_SIMPLE:
        printf("%lu.%03lu\n", 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;
    }

    free(pth_tab);

    return 0;
}