net/mlx5e: xsk: Use umr_mode to calculate striding RQ parameters

Instead of passing the unaligned flag, pass an enum that indicates the
UMR mode. The next commit will add the third mode (KLM for certain
configurations of XSK), which will be added to this enum instead of
adding another bool flag everywhere.

Signed-off-by: Maxim Mikityanskiy <maximmi@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 88 insertions, 38 deletions

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/params.c b/drivers/net/ethernet/mellanox/mlx5/core/en/params.c
index ac4d70bb21e8..b57855bf7629 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en/params.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en/params.c
@@ -27,9 +27,48 @@ u8 mlx5e_mpwrq_page_shift(struct mlx5_core_dev *mdev, struct mlx5e_xsk_param *xs
 	return max(req_page_shift, min_page_shift);
 }
 
-u8 mlx5e_mpwrq_log_wqe_sz(struct mlx5_core_dev *mdev, u8 page_shift, bool unaligned)
+enum mlx5e_mpwrq_umr_mode
+mlx5e_mpwrq_umr_mode(struct mlx5_core_dev *mdev, struct mlx5e_xsk_param *xsk)
+{
+	/* Different memory management schemes use different mechanisms to map
+	 * user-mode memory. The stricter guarantees we have, the faster
+	 * mechanisms we use:
+	 * 1. MTT - direct mapping in page granularity.
+	 * 2. KSM - indirect mapping to another MKey to arbitrary addresses, but
+	 *    all mappings have the same size.
+	 */
+	bool unaligned = xsk ? xsk->unaligned : false;
+
+	/* XSK frames can start at arbitrary unaligned locations, but they all
+	 * have the same size which is a power of two. It allows to optimize to
+	 * one KSM per frame.
+	 */
+	if (unaligned)
+		return MLX5E_MPWRQ_UMR_MODE_UNALIGNED;
+
+	/* XSK: frames are naturally aligned, MTT can be used.
+	 * Non-XSK: Allocations happen in units of CPU pages, therefore, the
+	 * mappings are naturally aligned.
+	 */
+	return MLX5E_MPWRQ_UMR_MODE_ALIGNED;
+}
+
+u8 mlx5e_mpwrq_umr_entry_size(enum mlx5e_mpwrq_umr_mode mode)
 {
-	u8 umr_entry_size = unaligned ? sizeof(struct mlx5_ksm) : sizeof(struct mlx5_mtt);
+	switch (mode) {
+	case MLX5E_MPWRQ_UMR_MODE_ALIGNED:
+		return sizeof(struct mlx5_mtt);
+	case MLX5E_MPWRQ_UMR_MODE_UNALIGNED:
+		return sizeof(struct mlx5_ksm);
+	}
+	WARN_ONCE(1, "MPWRQ UMR mode %d is not known\n", mode);
+	return 0;
+}
+
+u8 mlx5e_mpwrq_log_wqe_sz(struct mlx5_core_dev *mdev, u8 page_shift,
+			  enum mlx5e_mpwrq_umr_mode umr_mode)
+{
+	u8 umr_entry_size = mlx5e_mpwrq_umr_entry_size(umr_mode);
 	u8 max_pages_per_wqe, max_log_mpwqe_size;
 	u16 max_wqe_size;
 
@@ -44,9 +83,10 @@ u8 mlx5e_mpwrq_log_wqe_sz(struct mlx5_core_dev *mdev, u8 page_shift, bool unalig
 	return min_t(u8, max_log_mpwqe_size, MLX5_MPWRQ_MAX_LOG_WQE_SZ);
 }
 
-u8 mlx5e_mpwrq_pages_per_wqe(struct mlx5_core_dev *mdev, u8 page_shift, bool unaligned)
+u8 mlx5e_mpwrq_pages_per_wqe(struct mlx5_core_dev *mdev, u8 page_shift,
+			     enum mlx5e_mpwrq_umr_mode umr_mode)
 {
-	u8 log_wqe_sz = mlx5e_mpwrq_log_wqe_sz(mdev, page_shift, unaligned);
+	u8 log_wqe_sz = mlx5e_mpwrq_log_wqe_sz(mdev, page_shift, umr_mode);
 	u8 pages_per_wqe;
 
 	pages_per_wqe = log_wqe_sz > page_shift ? (1 << (log_wqe_sz - page_shift)) : 1;
@@ -59,10 +99,11 @@ u8 mlx5e_mpwrq_pages_per_wqe(struct mlx5_core_dev *mdev, u8 page_shift, bool una
 	return pages_per_wqe;
 }
 
-u16 mlx5e_mpwrq_umr_wqe_sz(struct mlx5_core_dev *mdev, u8 page_shift, bool unaligned)
+u16 mlx5e_mpwrq_umr_wqe_sz(struct mlx5_core_dev *mdev, u8 page_shift,
+			   enum mlx5e_mpwrq_umr_mode umr_mode)
 {
-	u8 umr_entry_size = unaligned ? sizeof(struct mlx5_ksm) : sizeof(struct mlx5_mtt);
-	u8 pages_per_wqe = mlx5e_mpwrq_pages_per_wqe(mdev, page_shift, unaligned);
+	u8 pages_per_wqe = mlx5e_mpwrq_pages_per_wqe(mdev, page_shift, umr_mode);
+	u8 umr_entry_size = mlx5e_mpwrq_umr_entry_size(umr_mode);
 	u16 umr_wqe_sz;
 
 	umr_wqe_sz = sizeof(struct mlx5e_umr_wqe) +
@@ -73,25 +114,30 @@ u16 mlx5e_mpwrq_umr_wqe_sz(struct mlx5_core_dev *mdev, u8 page_shift, bool unali
 	return umr_wqe_sz;
 }
 
-u8 mlx5e_mpwrq_umr_wqebbs(struct mlx5_core_dev *mdev, u8 page_shift, bool unaligned)
+u8 mlx5e_mpwrq_umr_wqebbs(struct mlx5_core_dev *mdev, u8 page_shift,
+			  enum mlx5e_mpwrq_umr_mode umr_mode)
 {
-	return DIV_ROUND_UP(mlx5e_mpwrq_umr_wqe_sz(mdev, page_shift, unaligned),
+	return DIV_ROUND_UP(mlx5e_mpwrq_umr_wqe_sz(mdev, page_shift, umr_mode),
 			    MLX5_SEND_WQE_BB);
 }
 
-u8 mlx5e_mpwrq_mtts_per_wqe(struct mlx5_core_dev *mdev, u8 page_shift, bool unaligned)
+u8 mlx5e_mpwrq_mtts_per_wqe(struct mlx5_core_dev *mdev, u8 page_shift,
+			    enum mlx5e_mpwrq_umr_mode umr_mode)
 {
+	u8 pages_per_wqe = mlx5e_mpwrq_pages_per_wqe(mdev, page_shift, umr_mode);
+
 	/* Add another page as a buffer between WQEs. This page will absorb
 	 * write overflow by the hardware, when receiving packets larger than
 	 * MTU. These oversize packets are dropped by the driver at a later
 	 * stage.
 	 */
-	return MLX5_ALIGN_MTTS(mlx5e_mpwrq_pages_per_wqe(mdev, page_shift, unaligned) + 1);
+	return MLX5_ALIGN_MTTS(pages_per_wqe + 1);
 }
 
-u32 mlx5e_mpwrq_max_num_entries(struct mlx5_core_dev *mdev, bool unaligned)
+u32 mlx5e_mpwrq_max_num_entries(struct mlx5_core_dev *mdev,
+				enum mlx5e_mpwrq_umr_mode umr_mode)
 {
-	if (unaligned)
+	if (umr_mode == MLX5E_MPWRQ_UMR_MODE_UNALIGNED)
 		return min(MLX5E_MAX_RQ_NUM_KSMS,
 			   1 << MLX5_CAP_GEN(mdev, log_max_klm_list_size));
 
@@ -99,18 +145,19 @@ u32 mlx5e_mpwrq_max_num_entries(struct mlx5_core_dev *mdev, bool unaligned)
 }
 
 static u8 mlx5e_mpwrq_max_log_rq_size(struct mlx5_core_dev *mdev, u8 page_shift,
-				      bool unaligned)
+				      enum mlx5e_mpwrq_umr_mode umr_mode)
 {
-	u8 mtts_per_wqe = mlx5e_mpwrq_mtts_per_wqe(mdev, page_shift, unaligned);
-	u32 max_entries = mlx5e_mpwrq_max_num_entries(mdev, unaligned);
+	u8 mtts_per_wqe = mlx5e_mpwrq_mtts_per_wqe(mdev, page_shift, umr_mode);
+	u32 max_entries = mlx5e_mpwrq_max_num_entries(mdev, umr_mode);
 
 	return ilog2(max_entries / mtts_per_wqe);
 }
 
-u8 mlx5e_mpwrq_max_log_rq_pkts(struct mlx5_core_dev *mdev, u8 page_shift, bool unaligned)
+u8 mlx5e_mpwrq_max_log_rq_pkts(struct mlx5_core_dev *mdev, u8 page_shift,
+			       enum mlx5e_mpwrq_umr_mode umr_mode)
 {
-	return mlx5e_mpwrq_max_log_rq_size(mdev, page_shift, unaligned) +
-		mlx5e_mpwrq_log_wqe_sz(mdev, page_shift, unaligned) -
+	return mlx5e_mpwrq_max_log_rq_size(mdev, page_shift, umr_mode) +
+		mlx5e_mpwrq_log_wqe_sz(mdev, page_shift, umr_mode) -
 		MLX5E_ORDER2_MAX_PACKET_MTU;
 }
 
@@ -171,10 +218,10 @@ static u8 mlx5e_mpwqe_log_pkts_per_wqe(struct mlx5_core_dev *mdev,
 				       struct mlx5e_xsk_param *xsk)
 {
 	u32 linear_stride_sz = mlx5e_rx_get_linear_stride_sz(mdev, params, xsk, true);
+	enum mlx5e_mpwrq_umr_mode umr_mode = mlx5e_mpwrq_umr_mode(mdev, xsk);
 	u8 page_shift = mlx5e_mpwrq_page_shift(mdev, xsk);
-	bool unaligned = xsk ? xsk->unaligned : false;
 
-	return mlx5e_mpwrq_log_wqe_sz(mdev, page_shift, unaligned) -
+	return mlx5e_mpwrq_log_wqe_sz(mdev, page_shift, umr_mode) -
 		order_base_2(linear_stride_sz);
 }
 
@@ -200,10 +247,11 @@ bool mlx5e_rx_is_linear_skb(struct mlx5_core_dev *mdev,
 
 static bool mlx5e_verify_rx_mpwqe_strides(struct mlx5_core_dev *mdev,
 					  u8 log_stride_sz, u8 log_num_strides,
-					  u8 page_shift, bool unaligned)
+					  u8 page_shift,
+					  enum mlx5e_mpwrq_umr_mode umr_mode)
 {
 	if (log_stride_sz + log_num_strides !=
-	    mlx5e_mpwrq_log_wqe_sz(mdev, page_shift, unaligned))
+	    mlx5e_mpwrq_log_wqe_sz(mdev, page_shift, umr_mode))
 		return false;
 
 	if (log_stride_sz < MLX5_MPWQE_LOG_STRIDE_SZ_BASE ||
@@ -223,8 +271,8 @@ bool mlx5e_rx_mpwqe_is_linear_skb(struct mlx5_core_dev *mdev,
 				  struct mlx5e_params *params,
 				  struct mlx5e_xsk_param *xsk)
 {
+	enum mlx5e_mpwrq_umr_mode umr_mode = mlx5e_mpwrq_umr_mode(mdev, xsk);
 	u8 page_shift = mlx5e_mpwrq_page_shift(mdev, xsk);
-	bool unaligned = xsk ? xsk->unaligned : false;
 	u8 log_num_strides;
 	u8 log_stride_sz;
 	u8 log_wqe_sz;
@@ -233,7 +281,7 @@ bool mlx5e_rx_mpwqe_is_linear_skb(struct mlx5_core_dev *mdev,
 		return false;
 
 	log_stride_sz = order_base_2(mlx5e_rx_get_linear_stride_sz(mdev, params, xsk, true));
-	log_wqe_sz = mlx5e_mpwrq_log_wqe_sz(mdev, page_shift, unaligned);
+	log_wqe_sz = mlx5e_mpwrq_log_wqe_sz(mdev, page_shift, umr_mode);
 
 	if (log_wqe_sz < log_stride_sz)
 		return false;
@@ -242,19 +290,19 @@ bool mlx5e_rx_mpwqe_is_linear_skb(struct mlx5_core_dev *mdev,
 
 	return mlx5e_verify_rx_mpwqe_strides(mdev, log_stride_sz,
 					     log_num_strides, page_shift,
-					     unaligned);
+					     umr_mode);
 }
 
 u8 mlx5e_mpwqe_get_log_rq_size(struct mlx5_core_dev *mdev,
 			       struct mlx5e_params *params,
 			       struct mlx5e_xsk_param *xsk)
 {
+	enum mlx5e_mpwrq_umr_mode umr_mode = mlx5e_mpwrq_umr_mode(mdev, xsk);
 	u8 log_pkts_per_wqe, page_shift, max_log_rq_size;
-	bool unaligned = xsk ? xsk->unaligned : false;
 
 	log_pkts_per_wqe = mlx5e_mpwqe_log_pkts_per_wqe(mdev, params, xsk);
 	page_shift = mlx5e_mpwrq_page_shift(mdev, xsk);
-	max_log_rq_size = mlx5e_mpwrq_max_log_rq_size(mdev, page_shift, unaligned);
+	max_log_rq_size = mlx5e_mpwrq_max_log_rq_size(mdev, page_shift, umr_mode);
 
 	/* Numbers are unsigned, don't subtract to avoid underflow. */
 	if (params->log_rq_mtu_frames <
@@ -308,10 +356,10 @@ u8 mlx5e_mpwqe_get_log_num_strides(struct mlx5_core_dev *mdev,
 				   struct mlx5e_params *params,
 				   struct mlx5e_xsk_param *xsk)
 {
+	enum mlx5e_mpwrq_umr_mode umr_mode = mlx5e_mpwrq_umr_mode(mdev, xsk);
 	u8 page_shift = mlx5e_mpwrq_page_shift(mdev, xsk);
-	bool unaligned = xsk ? xsk->unaligned : false;
 
-	return mlx5e_mpwrq_log_wqe_sz(mdev, page_shift, unaligned) -
+	return mlx5e_mpwrq_log_wqe_sz(mdev, page_shift, umr_mode) -
 		mlx5e_mpwqe_get_log_stride_size(mdev, params, xsk);
 }
 
@@ -460,9 +508,10 @@ bool slow_pci_heuristic(struct mlx5_core_dev *mdev)
 
 int mlx5e_mpwrq_validate_regular(struct mlx5_core_dev *mdev, struct mlx5e_params *params)
 {
+	enum mlx5e_mpwrq_umr_mode umr_mode = mlx5e_mpwrq_umr_mode(mdev, NULL);
 	u8 page_shift = mlx5e_mpwrq_page_shift(mdev, NULL);
 
-	if (!mlx5e_check_fragmented_striding_rq_cap(mdev, page_shift, false))
+	if (!mlx5e_check_fragmented_striding_rq_cap(mdev, page_shift, umr_mode))
 		return -EOPNOTSUPP;
 
 	if (params->xdp_prog && !mlx5e_rx_mpwqe_is_linear_skb(mdev, params, NULL))
@@ -474,11 +523,12 @@ int mlx5e_mpwrq_validate_regular(struct mlx5_core_dev *mdev, struct mlx5e_params
 int mlx5e_mpwrq_validate_xsk(struct mlx5_core_dev *mdev, struct mlx5e_params *params,
 			     struct mlx5e_xsk_param *xsk)
 {
+	enum mlx5e_mpwrq_umr_mode umr_mode = mlx5e_mpwrq_umr_mode(mdev, xsk);
 	u8 page_shift = mlx5e_mpwrq_page_shift(mdev, xsk);
 	bool unaligned = xsk ? xsk->unaligned : false;
 	u16 max_mtu_pkts;
 
-	if (!mlx5e_check_fragmented_striding_rq_cap(mdev, page_shift, xsk->unaligned))
+	if (!mlx5e_check_fragmented_striding_rq_cap(mdev, page_shift, umr_mode))
 		return -EOPNOTSUPP;
 
 	if (!mlx5e_rx_mpwqe_is_linear_skb(mdev, params, xsk))
@@ -781,16 +831,16 @@ int mlx5e_build_rq_param(struct mlx5_core_dev *mdev,
 	case MLX5_WQ_TYPE_LINKED_LIST_STRIDING_RQ: {
 		u8 log_wqe_num_of_strides = mlx5e_mpwqe_get_log_num_strides(mdev, params, xsk);
 		u8 log_wqe_stride_size = mlx5e_mpwqe_get_log_stride_size(mdev, params, xsk);
+		enum mlx5e_mpwrq_umr_mode umr_mode = mlx5e_mpwrq_umr_mode(mdev, xsk);
 		u8 page_shift = mlx5e_mpwrq_page_shift(mdev, xsk);
-		bool unaligned = xsk ? xsk->unaligned : false;
 
 		if (!mlx5e_verify_rx_mpwqe_strides(mdev, log_wqe_stride_size,
 						   log_wqe_num_of_strides,
-						   page_shift, unaligned)) {
+						   page_shift, umr_mode)) {
 			mlx5_core_err(mdev,
-				      "Bad RX MPWQE params: log_stride_size %u, log_num_strides %u, unaligned %d\n",
+				      "Bad RX MPWQE params: log_stride_size %u, log_num_strides %u, umr_mode %d\n",
 				      log_wqe_stride_size, log_wqe_num_of_strides,
-				      unaligned);
+				      umr_mode);
 			return -EINVAL;
 		}
 
@@ -974,11 +1024,11 @@ static u32 mlx5e_mpwrq_total_umr_wqebbs(struct mlx5_core_dev *mdev,
 					struct mlx5e_params *params,
 					struct mlx5e_xsk_param *xsk)
 {
+	enum mlx5e_mpwrq_umr_mode umr_mode = mlx5e_mpwrq_umr_mode(mdev, xsk);
 	u8 page_shift = mlx5e_mpwrq_page_shift(mdev, xsk);
-	bool unaligned = xsk ? xsk->unaligned : false;
 	u8 umr_wqebbs;
 
-	umr_wqebbs = mlx5e_mpwrq_umr_wqebbs(mdev, page_shift, unaligned);
+	umr_wqebbs = mlx5e_mpwrq_umr_wqebbs(mdev, page_shift, umr_mode);
 
 	return umr_wqebbs * (1 << mlx5e_mpwqe_get_log_rq_size(mdev, params, xsk));
 }