rte_mempool_get_priv

/**
 * Calculate the size of the mempool header.
 *
 * @param mp
 *   Pointer to the memory pool.
 * @param cs
 *   Size of the per-lcore cache.
 */
#define MEMPOOL_HEADER_SIZE(mp, cs) 
        (sizeof(*(mp)) + (((cs) == 0) ? 0 : 
        (sizeof(struct rte_mempool_cache) * RTE_MAX_LCORE)))

static inline void *rte_mempool_get_priv(struct rte_mempool *mp)
{
        return (char *)mp +
                MEMPOOL_HEADER_SIZE(mp, mp->cache_size);
}

#include <stdio.h>
#include <unistd.h>
#include <rte_memory.h>
#include <rte_ring.h>
#include <rte_mempool.h>

#define RING_SIZE            64
static const char *_MSG_POOL = "MSG_POOL";
struct rte_mempool *message_pool;
struct lcore_params {
    struct rte_ring *send_ring, *recv_ring;
};

struct data {
    uint32_t value;
};
struct private_data {
    uint32_t value;
};

static int
lcore_recv(struct lcore_params *p)
{
    unsigned lcore_id = rte_lcore_id();
    printf("Starting core %u
", lcore_id);
    void * vp;
    while (rte_ring_dequeue(p->send_ring, &vp) != 0){
        usleep(5);
    }
    struct data * d = (struct data *) vp;
        struct private_data * priv = (struct private_data *)rte_mempool_get_priv(message_pool);
    printf("core %u: Received %d and private data %u
", lcore_id, d->value, priv->value);
    d->value ++;
    rte_ring_enqueue(p->recv_ring, (void *)d);

    return 0;
}

static void
enqueue_sample_data(struct rte_ring * ring)
{
    int i;
    uint32_t values[4] = {1, 3, 5, 8};
    for (i = 0; i < 4; ++i) {
        void *p  = NULL;
        if (rte_mempool_get(message_pool, &p) < 0)
                rte_panic("Failed to get message buffer
");
        struct data * msg = (struct data *)p;
        msg->value = values[i];
        if (rte_ring_enqueue(ring, msg) < 0) {
                printf("Failed to send message - message discarded
");
                rte_mempool_put(message_pool, p);
        }
    }
    struct private_data * priv = (struct private_data *)rte_mempool_get_priv(message_pool);
    priv->value =1000;

}



static void
print_ring(struct rte_ring * ring)
{
    struct data * d;
    while (rte_ring_dequeue(ring, (void *)&d) == 0) {
        printf("DEQ-DATA:%d
", d->value);
        //free(d);
    }
}

int
main(int argc, char **argv)
{
    int ret;
    unsigned lcore_id;
        //const unsigned pool_size = sizeof(struct data) * 4;
        const unsigned pool_size = 64;
        const unsigned pool_cache = 32;
        const unsigned priv_data_sz = sizeof(struct private_data);
    ret = rte_eal_init(argc, argv);
    if (ret < 0)
        rte_exit(EXIT_FAILURE, "Cannot init EAL
");

    struct lcore_params params;

    params.send_ring = rte_ring_create("R1", RING_SIZE, SOCKET_ID_ANY, 0/*RING_F_SP_ENQ*/);
    if (!params.send_ring) {
        rte_exit(EXIT_FAILURE, "Problem getting sending ring
");
    }


    params.recv_ring = rte_ring_create("R2", RING_SIZE, SOCKET_ID_ANY, 0/*RING_F_SC_DEQ*/);
    if (!params.recv_ring) {
        rte_exit(EXIT_FAILURE, "Problem getting receiving ring
");
    }

        message_pool = rte_mempool_create(_MSG_POOL, pool_size,
                                sizeof(struct data), pool_cache, priv_data_sz,
                                NULL, NULL, NULL, NULL,
                                rte_socket_id(), 0);
         if (message_pool == NULL)
                rte_exit(EXIT_FAILURE, "Problem getting message pool
");
    enqueue_sample_data(params.send_ring);


    printf("Starting lcores.
");
    RTE_LCORE_FOREACH_SLAVE(lcore_id) {
        rte_eal_remote_launch((lcore_function_t*)lcore_recv, &params, lcore_id);
    }

    printf("Waiting for lcores to finish.
");
    rte_eal_mp_wait_lcore();

    print_ring(params.recv_ring);
        getchar();
    return 0;
}

 private data 共享

EAL:   probe driver: 19e5:a221 net_hns3
Starting lcores.
Starting core 1
core 1: Received 1 and private data 1000
Starting core 2
core 2: Received 3 and private data 1000
Starting core 4
core 4: Received 5 and private data 1000
Waiting for lcores to finish.
Starting core 3
core 3: Received 8 and private data 1000
DEQ-DATA:2
DEQ-DATA:4
DEQ-DATA:6
DEQ-DATA:9
q