From: Maxim Mikityanskiy <maximmi@nvidia.com>
Date: Mon, 31 Jan 2022 17:41:31 +0200
Subject: net/mlx5e: Don't prefill WQEs in XDP SQ in the multi buffer mode
Patch-mainline: v5.18-rc1
Git-commit: 9ded70fa1d8186135090f09638db7d8126dca0db
References: jsc#PED-1549
When MPWQE is disabled, mlx5e_open_xdpsq() prefills the common fields of
WQEs in the XDP SQ to save time when sending packets.
mlx5e_xmit_xdp_frame() runs on the prefilled fields, however, sending
multi buffer XDP frames would require changing some of these fields on a
per-packet basis. Besides that, mlx5e_xmit_xdp_frame() will be used as a
fallback to send multi buffer XDP frames when MPWQE is enabled (MPWQE
can only handle linear packets).
In order to prepare for XDP multi buffer support, this commit introduces
a mode for mlx5e_xmit_xdp_frame() that fills all the fields itself.
Signed-off-by: Maxim Mikityanskiy <maximmi@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
drivers/net/ethernet/mellanox/mlx5/core/en.h | 1
drivers/net/ethernet/mellanox/mlx5/core/en/params.c | 4 +-
drivers/net/ethernet/mellanox/mlx5/core/en/params.h | 2 +
drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c | 32 +++++++++++++++--
drivers/net/ethernet/mellanox/mlx5/core/en/xsk/setup.c | 2 -
drivers/net/ethernet/mellanox/mlx5/core/en_main.c | 10 ++++-
6 files changed, 46 insertions(+), 5 deletions(-)
--- a/drivers/net/ethernet/mellanox/mlx5/core/en.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en.h
@@ -405,6 +405,7 @@ enum {
MLX5E_SQ_STATE_VLAN_NEED_L2_INLINE,
MLX5E_SQ_STATE_PENDING_XSK_TX,
MLX5E_SQ_STATE_PENDING_TLS_RX_RESYNC,
+ MLX5E_SQ_STATE_XDP_MULTIBUF,
};
struct mlx5e_tx_mpwqe {
--- a/drivers/net/ethernet/mellanox/mlx5/core/en/params.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en/params.c
@@ -843,6 +843,7 @@ static void mlx5e_build_async_icosq_para
void mlx5e_build_xdpsq_param(struct mlx5_core_dev *mdev,
struct mlx5e_params *params,
+ struct mlx5e_xsk_param *xsk,
struct mlx5e_sq_param *param)
{
void *sqc = param->sqc;
@@ -851,6 +852,7 @@ void mlx5e_build_xdpsq_param(struct mlx5
mlx5e_build_sq_param_common(mdev, param);
MLX5_SET(wq, wq, log_wq_sz, params->log_sq_size);
param->is_mpw = MLX5E_GET_PFLAG(params, MLX5E_PFLAG_XDP_TX_MPWQE);
+ param->is_xdp_mb = !mlx5e_rx_is_linear_skb(params, xsk);
mlx5e_build_tx_cq_param(mdev, params, ¶m->cqp);
}
@@ -870,7 +872,7 @@ int mlx5e_build_channel_param(struct mlx
async_icosq_log_wq_sz = mlx5e_build_async_icosq_log_wq_sz(mdev);
mlx5e_build_sq_param(mdev, params, &cparam->txq_sq);
- mlx5e_build_xdpsq_param(mdev, params, &cparam->xdp_sq);
+ mlx5e_build_xdpsq_param(mdev, params, NULL, &cparam->xdp_sq);
mlx5e_build_icosq_param(mdev, icosq_log_wq_sz, &cparam->icosq);
mlx5e_build_async_icosq_param(mdev, async_icosq_log_wq_sz, &cparam->async_icosq);
--- a/drivers/net/ethernet/mellanox/mlx5/core/en/params.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en/params.h
@@ -31,6 +31,7 @@ struct mlx5e_sq_param {
struct mlx5_wq_param wq;
bool is_mpw;
bool is_tls;
+ bool is_xdp_mb;
u16 stop_room;
};
@@ -155,6 +156,7 @@ void mlx5e_build_tx_cq_param(struct mlx5
struct mlx5e_cq_param *param);
void mlx5e_build_xdpsq_param(struct mlx5_core_dev *mdev,
struct mlx5e_params *params,
+ struct mlx5e_xsk_param *xsk,
struct mlx5e_sq_param *param);
int mlx5e_build_channel_param(struct mlx5_core_dev *mdev,
struct mlx5e_params *params,
--- a/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c
@@ -323,6 +323,7 @@ mlx5e_xmit_xdp_frame(struct mlx5e_xdpsq
dma_addr_t dma_addr = xdptxd->dma_addr;
u32 dma_len = xdptxd->len;
+ u16 ds_cnt, inline_hdr_sz;
struct mlx5e_xdpsq_stats *stats = sq->stats;
@@ -338,7 +339,8 @@ mlx5e_xmit_xdp_frame(struct mlx5e_xdpsq
if (unlikely(check_result < 0))
return false;
- cseg->fm_ce_se = 0;
+ ds_cnt = MLX5E_TX_WQE_EMPTY_DS_COUNT + 1;
+ inline_hdr_sz = 0;
/* copy the inline part if required */
if (sq->min_inline_mode != MLX5_INLINE_MODE_NONE) {
@@ -347,7 +349,9 @@ mlx5e_xmit_xdp_frame(struct mlx5e_xdpsq
MLX5E_XDP_MIN_INLINE - sizeof(eseg->inline_hdr.start));
dma_len -= MLX5E_XDP_MIN_INLINE;
dma_addr += MLX5E_XDP_MIN_INLINE;
+ inline_hdr_sz = MLX5E_XDP_MIN_INLINE;
dseg++;
+ ds_cnt++;
}
/* write the dma part */
@@ -356,7 +360,31 @@ mlx5e_xmit_xdp_frame(struct mlx5e_xdpsq
cseg->opmod_idx_opcode = cpu_to_be32((sq->pc << 8) | MLX5_OPCODE_SEND);
- sq->pc++;
+ if (unlikely(test_bit(MLX5E_SQ_STATE_XDP_MULTIBUF, &sq->state))) {
+ u8 num_pkts = 1;
+ u8 num_wqebbs;
+
+ memset(&cseg->signature, 0, sizeof(*cseg) -
+ sizeof(cseg->opmod_idx_opcode) - sizeof(cseg->qpn_ds));
+ memset(eseg, 0, sizeof(*eseg) - sizeof(eseg->trailer));
+
+ eseg->inline_hdr.sz = cpu_to_be16(inline_hdr_sz);
+ dseg->lkey = sq->mkey_be;
+
+ cseg->qpn_ds = cpu_to_be32((sq->sqn << 8) | ds_cnt);
+
+ num_wqebbs = DIV_ROUND_UP(ds_cnt, MLX5_SEND_WQEBB_NUM_DS);
+ sq->db.wqe_info[pi] = (struct mlx5e_xdp_wqe_info) {
+ .num_wqebbs = num_wqebbs,
+ .num_pkts = num_pkts,
+ };
+
+ sq->pc += num_wqebbs;
+ } else {
+ cseg->fm_ce_se = 0;
+
+ sq->pc++;
+ }
sq->doorbell_cseg = cseg;
--- a/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/setup.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/setup.c
@@ -43,7 +43,7 @@ static void mlx5e_build_xsk_cparam(struc
struct mlx5e_channel_param *cparam)
{
mlx5e_build_rq_param(mdev, params, xsk, q_counter, &cparam->rq);
- mlx5e_build_xdpsq_param(mdev, params, &cparam->xdp_sq);
+ mlx5e_build_xdpsq_param(mdev, params, xsk, &cparam->xdp_sq);
}
static int mlx5e_init_xsk_rq(struct mlx5e_channel *c,
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
@@ -1666,13 +1666,21 @@ int mlx5e_open_xdpsq(struct mlx5e_channe
csp.wq_ctrl = &sq->wq_ctrl;
csp.min_inline_mode = sq->min_inline_mode;
set_bit(MLX5E_SQ_STATE_ENABLED, &sq->state);
+
+ /* Don't enable multi buffer on XDP_REDIRECT SQ, as it's not yet
+ * supported by upstream, and there is no defined trigger to allow
+ * transmitting redirected multi-buffer frames.
+ */
+ if (param->is_xdp_mb && !is_redirect)
+ set_bit(MLX5E_SQ_STATE_XDP_MULTIBUF, &sq->state);
+
err = mlx5e_create_sq_rdy(c->mdev, param, &csp, 0, &sq->sqn);
if (err)
goto err_free_xdpsq;
mlx5e_set_xmit_fp(sq, param->is_mpw);
- if (!param->is_mpw) {
+ if (!param->is_mpw && !test_bit(MLX5E_SQ_STATE_XDP_MULTIBUF, &sq->state)) {
unsigned int ds_cnt = MLX5E_XDP_TX_DS_COUNT;
unsigned int inline_hdr_sz = 0;
int i;