app/testpmd: fix refcnt in mbuf allocation

test-pmd txonly leaks mbuf from the pool.
The function tx_mbuf_alloc() does not change the refcnt
and the refcnt is 0 when it is first allocated.
However, rte_pktmbuf_free_seg called by the driver's xmit code decrements
reference count to -1. So mbuf never goes back to the pool.
As a result, txonly can't send packets after it exhausts the mempool.

The function tx_mbuf_alloc() was getting mbuf directly from mempool and so
was bypassing mbuf API.
The dedicated function is rte_pktmbuf_alloc() but it is much slower because
it does unnecessary initializations in rte_pktmbuf_reset().
By using the internal API __rte_mbuf_raw_alloc(), refcnt is correctly handled
without adding too much overload.

Signed-off-by: Dongsu Han <dongsuh@cs.cmu.edu>
Signed-off-by: Thomas Monjalon <thomas.monjalon@6wind.com>
Acked-by: Adrien Mazarguil <adrien.mazarguil@6wind.com>

diff --git a/app/test-pmd/txonly.c b/app/test-pmd/txonly.c
index 7f3b89c..63cc47a 100644 (file)
--- a/app/test-pmd/txonly.c
+++ b/app/test-pmd/txonly.c
@@ -92,11 +92,8 @@ static inline struct rte_mbuf *
 tx_mbuf_alloc(struct rte_mempool *mp)
 {
        struct rte_mbuf *m;
-       void *mb;
 
-       if (rte_mempool_get(mp, &mb) < 0)
-               return NULL;
-       m = (struct rte_mbuf *)mb;
+       m = __rte_mbuf_raw_alloc(mp);
        __rte_mbuf_sanity_check(m, RTE_MBUF_PKT, 1);
        return m;
 }