[dpdk-dev] [PATCH v4 3/8] net/mlx5: update Tx datapath definitions

[Yongseok Koh]

> On Jul 21, 2019, at 7:24 AM, Viacheslav Ovsiienko <viacheslavo at mellanox.com> wrote:
> 
> This patch updates Tx datapath definitions, mostly hardware related.
> The Tx descriptor structures are redefined with required fields,
> size definitions are renamed to reflect the meanings in more
> appropriate way. This is a preparation step before introducing
> the new Tx datapath implementation.
> 
> Signed-off-by: Viacheslav Ovsiienko <viacheslavo at mellanox.com>
> ---

Acked-by: Yongseok Koh <yskoh at mellanox.com>

> drivers/net/mlx5/mlx5_defs.h |   2 +-
> drivers/net/mlx5/mlx5_prm.h  | 164 +++++++++++++++++++++++++++++++++++++++----
> 2 files changed, 152 insertions(+), 14 deletions(-)
> 
> diff --git a/drivers/net/mlx5/mlx5_defs.h b/drivers/net/mlx5/mlx5_defs.h
> index 6861304..873a595 100644
> --- a/drivers/net/mlx5/mlx5_defs.h
> +++ b/drivers/net/mlx5/mlx5_defs.h
> @@ -58,7 +58,7 @@
> #define MLX5_MAX_XSTATS 32
> 
> /* Maximum Packet headers size (L2+L3+L4) for TSO. */
> -#define MLX5_MAX_TSO_HEADER 192
> +#define MLX5_MAX_TSO_HEADER (128u + 34u)
> 
> /* Threshold of buffer replenishment for vectorized Rx. */
> #define MLX5_VPMD_RXQ_RPLNSH_THRESH(n) \
> diff --git a/drivers/net/mlx5/mlx5_prm.h b/drivers/net/mlx5/mlx5_prm.h
> index dfd9317..97abdb2 100644
> --- a/drivers/net/mlx5/mlx5_prm.h
> +++ b/drivers/net/mlx5/mlx5_prm.h
> @@ -39,14 +39,85 @@
> /* Invalidate a CQE. */
> #define MLX5_CQE_INVALIDATE (MLX5_CQE_INVALID << 4)
> 
> -/* WQE DWORD size */
> -#define MLX5_WQE_DWORD_SIZE 16
> -
> -/* WQE size */
> -#define MLX5_WQE_SIZE (4 * MLX5_WQE_DWORD_SIZE)
> +/* WQE Segment sizes in bytes. */
> +#define MLX5_WSEG_SIZE 16u
> +#define MLX5_WQE_CSEG_SIZE sizeof(struct mlx5_wqe_cseg)
> +#define MLX5_WQE_DSEG_SIZE sizeof(struct mlx5_wqe_dseg)
> +#define MLX5_WQE_ESEG_SIZE sizeof(struct mlx5_wqe_eseg)
> +
> +/* WQE/WQEBB size in bytes. */
> +#define MLX5_WQE_SIZE sizeof(struct mlx5_wqe)
> +
> +/*
> + * Max size of a WQE session.
> + * Absolute maximum size is 63 (MLX5_DSEG_MAX) segments,
> + * the WQE size field in Control Segment is 6 bits wide.
> + */
> +#define MLX5_WQE_SIZE_MAX (60 * MLX5_WSEG_SIZE)
> +
> +/*
> + * Default minimum number of Tx queues for inlining packets.
> + * If there are less queues as specified we assume we have
> + * no enough CPU resources (cycles) to perform inlining,
> + * the PCIe throughput is not supposed as bottleneck and
> + * inlining is disabled.
> + */
> +#define MLX5_INLINE_MAX_TXQS 8u
> +#define MLX5_INLINE_MAX_TXQS_BLUEFIELD 16u
> +
> +/*
> + * Default packet length threshold to be inlined with
> + * enhanced MPW. If packet length exceeds the threshold
> + * the data are not inlined. Should be aligned in WQEBB
> + * boundary with accounting the title Control and Ethernet
> + * segments.
> + */
> +#define MLX5_EMPW_DEF_INLINE_LEN (3U * MLX5_WQE_SIZE + \
> +				  MLX5_DSEG_MIN_INLINE_SIZE - \
> +				  MLX5_WQE_DSEG_SIZE)
> +/*
> + * Maximal inline data length sent with enhanced MPW.
> + * Is based on maximal WQE size.
> + */
> +#define MLX5_EMPW_MAX_INLINE_LEN (MLX5_WQE_SIZE_MAX - \
> +				  MLX5_WQE_CSEG_SIZE - \
> +				  MLX5_WQE_ESEG_SIZE - \
> +				  MLX5_WQE_DSEG_SIZE + \
> +				  MLX5_DSEG_MIN_INLINE_SIZE)
> +/*
> + * Minimal amount of packets to be sent with EMPW.
> + * This limits the minimal required size of sent EMPW.
> + * If there are no enough resources to built minimal
> + * EMPW the sending loop exits.
> + */
> +#define MLX5_EMPW_MIN_PACKETS (2 + 3 * 4)
> +#define MLX5_EMPW_MAX_PACKETS ((MLX5_WQE_SIZE_MAX - \
> +				MLX5_WQE_CSEG_SIZE - \
> +				MLX5_WQE_ESEG_SIZE) / \
> +				MLX5_WSEG_SIZE)
> +/*
> + * Default packet length threshold to be inlined with
> + * ordinary SEND. Inlining saves the MR key search
> + * and extra PCIe data fetch transaction, but eats the
> + * CPU cycles.
> + */
> +#define MLX5_SEND_DEF_INLINE_LEN (5U * MLX5_WQE_SIZE + \
> +				  MLX5_ESEG_MIN_INLINE_SIZE - \
> +				  MLX5_WQE_CSEG_SIZE - \
> +				  MLX5_WQE_ESEG_SIZE - \
> +				  MLX5_WQE_DSEG_SIZE)
> +/*
> + * Maximal inline data length sent with ordinary SEND.
> + * Is based on maximal WQE size.
> + */
> +#define MLX5_SEND_MAX_INLINE_LEN (MLX5_WQE_SIZE_MAX - \
> +				  MLX5_WQE_CSEG_SIZE - \
> +				  MLX5_WQE_ESEG_SIZE - \
> +				  MLX5_WQE_DSEG_SIZE + \
> +				  MLX5_ESEG_MIN_INLINE_SIZE)
> 
> -#define MLX5_OPC_MOD_ENHANCED_MPSW 0
> -#define MLX5_OPCODE_ENHANCED_MPSW 0x29
> +/* Missed in mlv5dv.h, should define here. */
> +#define MLX5_OPCODE_ENHANCED_MPSW 0x29u
> 
> /* CQE value to inform that VLAN is stripped. */
> #define MLX5_CQE_VLAN_STRIPPED (1u << 0)
> @@ -114,6 +185,12 @@
> /* Inner L3 type is IPV6. */
> #define MLX5_ETH_WQE_L3_INNER_IPV6 (1u << 0)
> 
> +/* VLAN insertion flag. */
> +#define MLX5_ETH_WQE_VLAN_INSERT (1u << 31)
> +
> +/* Data inline segment flag. */
> +#define MLX5_ETH_WQE_DATA_INLINE (1u << 31)
> +
> /* Is flow mark valid. */
> #if RTE_BYTE_ORDER == RTE_LITTLE_ENDIAN
> #define MLX5_FLOW_MARK_IS_VALID(val) ((val) & 0xffffff00)
> @@ -130,12 +207,21 @@
> /* Default mark value used when none is provided. */
> #define MLX5_FLOW_MARK_DEFAULT 0xffffff
> 
> -/* Maximum number of DS in WQE. */
> +/* Maximum number of DS in WQE. Limited by 6-bit field. */
> #define MLX5_DSEG_MAX 63
> 
> /* The completion mode offset in the WQE control segment line 2. */
> #define MLX5_COMP_MODE_OFFSET 2
> 
> +/* Amount of data bytes in minimal inline data segment. */
> +#define MLX5_DSEG_MIN_INLINE_SIZE 12u
> +
> +/* Amount of data bytes in minimal inline eth segment. */
> +#define MLX5_ESEG_MIN_INLINE_SIZE 18u
> +
> +/* Amount of data bytes after eth data segment. */
> +#define MLX5_ESEG_EXTRA_DATA_SIZE 32u
> +
> /* Completion mode. */
> enum mlx5_completion_mode {
> 	MLX5_COMP_ONLY_ERR = 0x0,
> @@ -144,11 +230,6 @@ enum mlx5_completion_mode {
> 	MLX5_COMP_CQE_AND_EQE = 0x3,
> };
> 
> -/* Small common part of the WQE. */
> -struct mlx5_wqe {
> -	uint32_t ctrl[4];
> -};
> -
> /* MPW mode. */
> enum mlx5_mpw_mode {
> 	MLX5_MPW_DISABLED,
> @@ -156,6 +237,63 @@ enum mlx5_mpw_mode {
> 	MLX5_MPW_ENHANCED, /* Enhanced Multi-Packet Send WQE, a.k.a MPWv2. */
> };
> 
> +/* WQE Control segment. */
> +struct mlx5_wqe_cseg {
> +	uint32_t opcode;
> +	uint32_t sq_ds;
> +	uint32_t flags;
> +	uint32_t misc;
> +} __rte_packed __rte_aligned(MLX5_WSEG_SIZE);
> +
> +/* Header of data segment. Minimal size Data Segment */
> +struct mlx5_wqe_dseg {
> +	uint32_t bcount;
> +	union {
> +		uint8_t inline_data[MLX5_DSEG_MIN_INLINE_SIZE];
> +		struct {
> +			uint32_t lkey;
> +			uint64_t pbuf;
> +		} __rte_packed;
> +	};
> +} __rte_packed;
> +
> +/* Subset of struct WQE Ethernet Segment. */
> +struct mlx5_wqe_eseg {
> +	union {
> +		struct {
> +			uint32_t swp_offs;
> +			uint8_t	cs_flags;
> +			uint8_t	swp_flags;
> +			uint16_t mss;
> +			uint32_t metadata;
> +			uint16_t inline_hdr_sz;
> +			union {
> +				uint16_t inline_data;
> +				uint16_t vlan_tag;
> +			};
> +		} __rte_packed;
> +		struct {
> +			uint32_t offsets;
> +			uint32_t flags;
> +			uint32_t flow_metadata;
> +			uint32_t inline_hdr;
> +		} __rte_packed;
> +	};
> +} __rte_packed;
> +
> +/* The title WQEBB, header of WQE. */
> +struct mlx5_wqe {
> +	union {
> +		struct mlx5_wqe_cseg cseg;
> +		uint32_t ctrl[4];
> +	};
> +	struct mlx5_wqe_eseg eseg;
> +	union {
> +		struct mlx5_wqe_dseg dseg[2];
> +		uint8_t data[MLX5_ESEG_EXTRA_DATA_SIZE];
> +	};
> +} __rte_packed;
> +
> /* WQE for Multi-Packet RQ. */
> struct mlx5_wqe_mprq {
> 	struct mlx5_wqe_srq_next_seg next_seg;
> -- 
> 1.8.3.1
>