path: root/drivers/net/mlx5/mlx5_defs.h
diff options
authorYongseok Koh <>2018-08-02 14:00:07 -0700
committerShahaf Shuler <>2018-08-05 13:29:34 +0200
commitb85b719ab7c05dc821ff05bca9cd2b7ff7b0b7ed (patch)
tree2734f9ad493b98fe9a99c9daccd1014917a5f488 /drivers/net/mlx5/mlx5_defs.h
parente845e9ceb414b310aafaf3500b034478838e515a (diff)
net/mlx5: fix minimum number of Multi-Packet RQ buffers
If MPRQ is enabled, a PMD-private mempool is allocated. For ConnectX-4 Lx, the minimum number of strides is 512 which ConnectX-5 supports 8. This results in quite small number of elements for the MPRQ mempool. For example, if the size of Rx ring is configured as 512, only one MPRQ buffer can cover the whole ring. If there's only one Rx queue is configured. In the following code in mlx5_mprq_alloc_mp(), desc is 1 and obj_num will be 36 as a result. desc *= 4; obj_num = desc + MLX5_MPRQ_MP_CACHE_SZ * priv->rxqs_n; However, rte_mempool_create_empty() has a sanity check to refuse large per-lcore cache size compared to the number of elements. Cache flush threshold should not exceed the number of elements of a mempool. For the above example, the threshold is 32 * 1.5 = 48 which is larger than 36 and it fails to create the mempool. Fixes: 7d6bf6b866b8 ("net/mlx5: add Multi-Packet Rx support") Cc: Signed-off-by: Yongseok Koh <>
Diffstat (limited to 'drivers/net/mlx5/mlx5_defs.h')
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/net/mlx5/mlx5_defs.h b/drivers/net/mlx5/mlx5_defs.h
index 439cc15..f2a1679 100644
--- a/drivers/net/mlx5/mlx5_defs.h
+++ b/drivers/net/mlx5/mlx5_defs.h
@@ -126,7 +126,7 @@
#define MLX5_MPRQ_MIN_RXQS 12
/* Cache size of mempool for Multi-Packet RQ. */
-#define MLX5_MPRQ_MP_CACHE_SZ 32
+#define MLX5_MPRQ_MP_CACHE_SZ 32U
/* Definition of static_assert found in /usr/include/assert.h */