From: Dragos Tatulea dtatulea@nvidia.com
[ Upstream commit 34a79876d9f77e971115236bcf7b5d14a8ecf542 ]
Before this fix, running high rate traffic through XDP_REDIRECT with multibuf could overrun the fifo used to release the xdp frames after tx completion. This resulted in corrupted data being consumed on the free side.
The culplirt was a miscalculation of the fifo size: the maximum ratio between fifo entries / data segments was incorrect. This ratio serves to calculate the max fifo size for a full sq where each packet uses the worst case number of entries in the fifo.
This patch fixes the formula and names the constant. It also makes sure that future values will use a power of 2 number of entries for the fifo mask to work.
Signed-off-by: Dragos Tatulea dtatulea@nvidia.com Fixes: 3f734b8c594b ("net/mlx5e: XDP, Use multiple single-entry objects in xdpi_fifo") Reviewed-by: Tariq Toukan tariqt@nvidia.com Signed-off-by: Saeed Mahameed saeedm@nvidia.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/mellanox/mlx5/core/en/xdp.h | 2 ++ drivers/net/ethernet/mellanox/mlx5/core/en_main.c | 8 +++++--- 2 files changed, 7 insertions(+), 3 deletions(-)
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.h b/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.h index 9e8e6184f9e43..ecfe93a479da8 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.h +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.h @@ -84,6 +84,8 @@ enum mlx5e_xdp_xmit_mode { * MLX5E_XDP_XMIT_MODE_XSK: * none. */ +#define MLX5E_XDP_FIFO_ENTRIES2DS_MAX_RATIO 4 + union mlx5e_xdp_info { enum mlx5e_xdp_xmit_mode mode; union { diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c index 7e6d0489854e3..975c82df345cd 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c @@ -1298,11 +1298,13 @@ static int mlx5e_alloc_xdpsq_fifo(struct mlx5e_xdpsq *sq, int numa) { struct mlx5e_xdp_info_fifo *xdpi_fifo = &sq->db.xdpi_fifo; int wq_sz = mlx5_wq_cyc_get_size(&sq->wq); - int entries = wq_sz * MLX5_SEND_WQEBB_NUM_DS * 2; /* upper bound for maximum num of - * entries of all xmit_modes. - */ + int entries; size_t size;
+ /* upper bound for maximum num of entries of all xmit_modes. */ + entries = roundup_pow_of_two(wq_sz * MLX5_SEND_WQEBB_NUM_DS * + MLX5E_XDP_FIFO_ENTRIES2DS_MAX_RATIO); + size = array_size(sizeof(*xdpi_fifo->xi), entries); xdpi_fifo->xi = kvzalloc_node(size, GFP_KERNEL, numa); if (!xdpi_fifo->xi)