examples/multi_process/simple_mp/main.c

/* SPDX-License-Identifier: BSD-3-Clause
 * Copyright(c) 2010-2014 Intel Corporation
 */

/*
 * This sample application is a simple multi-process application which
 * demostrates sharing of queues and memory pools between processes, and
 * using those queues/pools for communication between the processes.
 *
 * Application is designed to run with two processes, a primary and a
 * secondary, and each accepts commands on the commandline, the most
 * important of which is "send", which just sends a string to the other
 * process.
 */

#include <stdio.h>
#include <string.h>
#include <stdint.h>
#include <inttypes.h>
#include <stdarg.h>
#include <errno.h>
#include <unistd.h>
#include <termios.h>
#include <sys/queue.h>

#include <rte_common.h>
#include <rte_memory.h>
#include <rte_launch.h>
#include <rte_eal.h>
#include <rte_per_lcore.h>
#include <rte_lcore.h>
#include <rte_debug.h>
#include <rte_atomic.h>
#include <rte_branch_prediction.h>
#include <rte_ring.h>
#include <rte_log.h>
#include <rte_mempool.h>
#include <cmdline_rdline.h>
#include <cmdline_parse.h>
#include <cmdline_parse_string.h>
#include <cmdline_socket.h>
#include <cmdline.h>
#include "mp_commands.h"

#define RTE_LOGTYPE_APP RTE_LOGTYPE_USER1

static const char *_MSG_POOL = "MSG_POOL";
static const char *_SEC_2_PRI = "SEC_2_PRI";
static const char *_PRI_2_SEC = "PRI_2_SEC";

struct rte_ring *send_ring, *recv_ring;
struct rte_mempool *message_pool;
volatile int quit = 0;

static int
lcore_recv(__attribute__((unused)) void *arg)
{
    unsigned lcore_id = rte_lcore_id();

    printf("Starting core %u\n", lcore_id);
    while (!quit){
        void *msg;
        if (rte_ring_dequeue(recv_ring, &msg) < 0){
            usleep(5);
            continue;
        }
        printf("core %u: Received '%s'\n", lcore_id, (char *)msg);
        rte_mempool_put(message_pool, msg);
    }

    return 0;
}

int
main(int argc, char **argv)
{
    const unsigned flags = 0;
    const unsigned ring_size = 64;
    const unsigned pool_size = 1024;
    const unsigned pool_cache = 32;
    const unsigned priv_data_sz = 0;

    int ret;
    unsigned lcore_id;

    ret = rte_eal_init(argc, argv);
    if (ret < 0)
        rte_exit(EXIT_FAILURE, "Cannot init EAL\n");

    if (rte_eal_process_type() == RTE_PROC_PRIMARY){
        send_ring = rte_ring_create(_PRI_2_SEC, ring_size, rte_socket_id(), flags);
        recv_ring = rte_ring_create(_SEC_2_PRI, ring_size, rte_socket_id(), flags);
        message_pool = rte_mempool_create(_MSG_POOL, pool_size,
                STR_TOKEN_SIZE, pool_cache, priv_data_sz,
                NULL, NULL, NULL, NULL,
                rte_socket_id(), flags);
    } else {
        recv_ring = rte_ring_lookup(_PRI_2_SEC);
        send_ring = rte_ring_lookup(_SEC_2_PRI);
        message_pool = rte_mempool_lookup(_MSG_POOL);
    }
    if (send_ring == NULL)
        rte_exit(EXIT_FAILURE, "Problem getting sending ring\n");
    if (recv_ring == NULL)
        rte_exit(EXIT_FAILURE, "Problem getting receiving ring\n");
    if (message_pool == NULL)
        rte_exit(EXIT_FAILURE, "Problem getting message pool\n");

    RTE_LOG(INFO, APP, "Finished Process Init.\n");

    /* call lcore_recv() on every slave lcore */
    RTE_LCORE_FOREACH_SLAVE(lcore_id) {
        rte_eal_remote_launch(lcore_recv, NULL, lcore_id);
    }

    /* call cmd prompt on master lcore */
    struct cmdline *cl = cmdline_stdin_new(simple_mp_ctx, "\nsimple_mp > ");
    if (cl == NULL)
        rte_exit(EXIT_FAILURE, "Cannot create cmdline instance\n");
    cmdline_interact(cl);
    cmdline_stdin_exit(cl);

    rte_eal_mp_wait_lcore();

    /* clean up the EAL */
    rte_eal_cleanup();

    return 0;
}