common/mlx5: fix memory region lookup on slow path

Memory region (MR) was being looked up incorrectly
for the data address of an externally-attached mbuf.
A search was attempted for the mempool of the mbuf,
while mbuf data address does not belong to this mempool
in case of externally-attached mbuf.
Only attempt the search:
1) for not externally-attached mbufs;
2) for mbufs coming from MPRQ mempool;
3) for externally-attached mbufs from mempools
   with pinned external buffers.

Fixes: 08ac03580ef2 ("common/mlx5: fix mempool registration")

Signed-off-by: Dmitry Kozlyuk <dkozlyuk@nvidia.com>
Reviewed-by: Matan Azrad <matan@nvidia.com>
Acked-by: Viacheslav Ovsiienko <viacheslavo@nvidia.com>

diff --git a/drivers/common/mlx5/mlx5_common_mr.c b/drivers/common/mlx5/mlx5_common_mr.c
index 01f35eb..c694aaf 100644 (file)
--- a/drivers/common/mlx5/mlx5_common_mr.c
+++ b/drivers/common/mlx5/mlx5_common_mr.c
@@ -2002,21 +2002,29 @@ mlx5_mr_mb2mr_bh(struct mlx5_mr_ctrl *mr_ctrl, struct rte_mbuf *mb)
                             dev_gen);
        struct mlx5_common_device *cdev =
                container_of(share_cache, struct mlx5_common_device, mr_scache);
+       bool external, mprq, pinned = false;
 
        /* Recover MPRQ mempool. */
-       if (RTE_MBUF_HAS_EXTBUF(mb) &&
-           mb->shinfo->free_cb == mlx5_mprq_buf_free_cb) {
+       external = RTE_MBUF_HAS_EXTBUF(mb);
+       if (external && mb->shinfo->free_cb == mlx5_mprq_buf_free_cb) {
+               mprq = true;
                buf = mb->shinfo->fcb_opaque;
                mp = buf->mp;
        } else {
+               mprq = false;
                mp = mlx5_mb2mp(mb);
+               pinned = rte_pktmbuf_priv_flags(mp) &
+                        RTE_PKTMBUF_POOL_F_PINNED_EXT_BUF;
+       }
+       if (!external || mprq || pinned) {
+               lkey = mlx5_mr_mempool2mr_bh(mr_ctrl, mp, addr);
+               if (lkey != UINT32_MAX)
+                       return lkey;
+               /* MPRQ is always registered. */
+               MLX5_ASSERT(!mprq);
        }
-       lkey = mlx5_mr_mempool2mr_bh(mr_ctrl, mp, addr);
-       if (lkey != UINT32_MAX)
-               return lkey;
        /* Register pinned external memory if the mempool is not used for Rx. */
-       if (cdev->config.mr_mempool_reg_en &&
-           (rte_pktmbuf_priv_flags(mp) & RTE_PKTMBUF_POOL_F_PINNED_EXT_BUF)) {
+       if (cdev->config.mr_mempool_reg_en && pinned) {
                if (mlx5_mr_mempool_register(cdev, mp, true) < 0)
                        return UINT32_MAX;
                lkey = mlx5_mr_mempool2mr_bh(mr_ctrl, mp, addr);