Re: [PATCH] net/mlx5: fix calculating TSO inline size
From: Nélio Laranjeiro <hidden>
Date: 2017-09-04 14:01:51
Hi Yongseok, Please see some comments below, On Thu, Aug 31, 2017 at 09:27:06AM -0700, Yongseok Koh wrote:
quoted hunk ↗ jump to hunk
Tx descriptor for TSO embeds packet header to be replicated. If Tx inline is enabled, there could be additional packet data inlined with 4B inline header ahead. And between the header and additional inlined packet data, there may be padding to make the inline part aligned to MLX5_WQE_DWORD_SIZE. In calculating the total size of inlined data, the size of inline header and padding is missing. Fixes: 3f13f8c23a7c ("net/mlx5: support hardware TSO") Cc: stable@dpdk.org Signed-off-by: Shahaf Shuler <redacted> Signed-off-by: Yongseok Koh <redacted> --- drivers/net/mlx5/mlx5_rxtx.c | 25 +++++++++---------------- 1 file changed, 9 insertions(+), 16 deletions(-)diff --git a/drivers/net/mlx5/mlx5_rxtx.c b/drivers/net/mlx5/mlx5_rxtx.c index fe9e7eac0..f89fa40b5 100644 --- a/drivers/net/mlx5/mlx5_rxtx.c +++ b/drivers/net/mlx5/mlx5_rxtx.c@@ -524,19 +521,20 @@ mlx5_tx_burst(void *dpdk_txq, struct rte_mbuf **pkts, uint16_t pkts_n) } /* Inline if enough room. */ if (inline_en || tso) { + uint32_t inl; uintptr_t end = (uintptr_t) (((uintptr_t)txq->wqes) + (1 << txq->wqe_n) * MLX5_WQE_SIZE); unsigned int inline_room = max_inline * RTE_CACHE_LINE_SIZE - - (pkt_inline_sz - 2); + (pkt_inline_sz - 2) - + !!tso * sizeof(inl);
Is not it dangerous to assume inl will always be 4 bytes long? Why not writing the real value instead?
uintptr_t addr_end = (addr + inline_room) &
~(RTE_CACHE_LINE_SIZE - 1);
unsigned int copy_b = (addr_end > addr) ?
RTE_MIN((addr_end - addr), length) :
0;
- raw += MLX5_WQE_DWORD_SIZE;
if (copy_b && ((end - (uintptr_t)raw) > copy_b)) {
/*
* One Dseg remains in the current WQE. ToThanks, -- Nélio Laranjeiro 6WIND