[PATCH v2 4/5] net/mlx5: drop unnecessary STRICT_ALIGN

[Stephen Hemminger <stephen@networkplumber.org>]

The transmit inline copy splits the 8 byte case into two 32 bit
moves when RTE_ARCH_STRICT_ALIGN is set. Only armv8 aarch32 ever
set that flag, and ARMv8 does unaligned access in hardware, so the
split gains nothing. Use a single 64 bit move.

The destination is inline_data, at offset 4 of a 16 byte aligned
dseg, so the 8 byte store is always misaligned. Write it through
the unaligned type; a plain uint64_t store there is undefined
behaviour and is reported by UBSAN.

The debug assertion on the inline data offset goes away with the
strict alignment path since the wider move has no such requirement.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
---
 drivers/net/mlx5/mlx5_tx.h | 12 +-----------
 1 file changed, 1 insertion(+), 11 deletions(-)

diff --git a/drivers/net/mlx5/mlx5_tx.h b/drivers/net/mlx5/mlx5_tx.h
index 682dc07718..69a18f8a49 100644
--- a/drivers/net/mlx5/mlx5_tx.h
+++ b/drivers/net/mlx5/mlx5_tx.h
@@ -1437,19 +1437,9 @@ mlx5_tx_dseg_iptr(struct mlx5_txq_data *__rte_restrict txq,
 	dst = (uintptr_t)&dseg->inline_data[0];
 	src = (uintptr_t)buf;
 	if (len & 0x08) {
-#ifdef RTE_ARCH_STRICT_ALIGN
-		MLX5_ASSERT(dst == RTE_PTR_ALIGN(dst, sizeof(uint32_t)));
-		*(uint32_t *)dst = *(unaligned_uint32_t *)src;
-		dst += sizeof(uint32_t);
-		src += sizeof(uint32_t);
-		*(uint32_t *)dst = *(unaligned_uint32_t *)src;
-		dst += sizeof(uint32_t);
-		src += sizeof(uint32_t);
-#else
-		*(uint64_t *)dst = *(unaligned_uint64_t *)src;
+		*(unaligned_uint64_t *)dst = *(unaligned_uint64_t *)src;
 		dst += sizeof(uint64_t);
 		src += sizeof(uint64_t);
-#endif
 	}
 	if (len & 0x04) {
 		*(uint32_t *)dst = *(unaligned_uint32_t *)src;
-- 
2.53.0