The mlx5 driver have a special drop-RQ queue (one per interface) that
simply drops all incoming traffic. It helps driver keep other HW
objects (flow steering) alive upon down/up operations. It is
temporarily pointed by flow steering objects during the interface
setup, and when interface is down. It lacks many fields that are set
in a regular RQ (for example its state is never switched to
MLX5_RQC_STATE_RDY). (Thanks to Tariq Toukan for explanation).
The XDP RX-queue info for this drop-RQ marked as unused, which
allow us to use the same takedown/free code path as other RX-queues.
Driver hook points for xdp_rxq_info:
* reg : mlx5e_alloc_rq()
* unused: mlx5e_alloc_drop_rq()
* unreg : mlx5e_free_rq()
Tested on actual hardware with samples/bpf program
Cc: Saeed Mahameed <sae...@mellanox.com>
Cc: Matan Barak <mat...@mellanox.com>
Cc: Tariq Toukan <tar...@mellanox.com>
Signed-off-by: Jesper Dangaard Brouer <bro...@redhat.com>
---
drivers/net/ethernet/mellanox/mlx5/core/en.h | 4 ++++
drivers/net/ethernet/mellanox/mlx5/core/en_main.c | 9 +++++++++
drivers/net/ethernet/mellanox/mlx5/core/en_rx.c | 1 +
3 files changed, 14 insertions(+)
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en.h
b/drivers/net/ethernet/mellanox/mlx5/core/en.h
index 543060c305a0..5299310f2481 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en.h
@@ -46,6 +46,7 @@
#include <linux/mlx5/transobj.h>
#include <linux/rhashtable.h>
#include <net/switchdev.h>
+#include <net/xdp.h>
#include "wq.h"
#include "mlx5_core.h"
#include "en_stats.h"
@@ -571,6 +572,9 @@ struct mlx5e_rq {
u32 rqn;
struct mlx5_core_dev *mdev;
struct mlx5_core_mkey umr_mkey;
+
+ /* XDP read-mostly */
+ struct xdp_rxq_info xdp_rxq;
} ____cacheline_aligned_in_smp;
struct mlx5e_channel {
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
index 3aa1c90e7c86..539bd1d24396 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
@@ -582,6 +582,9 @@ static int mlx5e_alloc_rq(struct mlx5e_channel *c,
goto err_rq_wq_destroy;
}
+ if (xdp_rxq_info_reg(&rq->xdp_rxq, rq->netdev, rq->ix) < 0)
+ goto err_rq_wq_destroy;
+
rq->buff.map_dir = rq->xdp_prog ? DMA_BIDIRECTIONAL : DMA_FROM_DEVICE;
rq->buff.headroom = params->rq_headroom;
@@ -687,6 +690,7 @@ static int mlx5e_alloc_rq(struct mlx5e_channel *c,
err_rq_wq_destroy:
if (rq->xdp_prog)
bpf_prog_put(rq->xdp_prog);
+ xdp_rxq_info_unreg(&rq->xdp_rxq);
mlx5_wq_destroy(&rq->wq_ctrl);
return err;
@@ -699,6 +703,8 @@ static void mlx5e_free_rq(struct mlx5e_rq *rq)
if (rq->xdp_prog)
bpf_prog_put(rq->xdp_prog);
+ xdp_rxq_info_unreg(&rq->xdp_rxq);
+
switch (rq->wq_type) {
case MLX5_WQ_TYPE_LINKED_LIST_STRIDING_RQ:
mlx5e_rq_free_mpwqe_info(rq);
@@ -2766,6 +2772,9 @@ static int mlx5e_alloc_drop_rq(struct mlx5_core_dev *mdev,
if (err)
return err;
+ /* Mark as unused given "Drop-RQ" packets never reach XDP */
+ xdp_rxq_info_unused(&rq->xdp_rxq);
+
rq->mdev = mdev;
return 0;
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
index 5b499c7a698f..7b38480811d4 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
@@ -812,6 +812,7 @@ static inline int mlx5e_xdp_handle(struct mlx5e_rq *rq,
xdp_set_data_meta_invalid(&xdp);
xdp.data_end = xdp.data + *len;
xdp.data_hard_start = va;
+ xdp.rxq = &rq->xdp_rxq;
act = bpf_prog_run_xdp(prog, &xdp);
switch (act) {
