redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

net/mlx5e: Don't trigger IRQ multiple times on XSK wakeup to avoid WQ overruns 

commit e7e0004abd upstream.

XSK wakeup function triggers NAPI by posting a NOP WQE to a special XSK
ICOSQ. When the application floods the driver with wakeup requests by
calling sendto() in a certain pattern that ends up in mlx5e_trigger_irq,
the XSK ICOSQ may overflow.

Multiple NOPs are not required and won't accelerate the process, so
avoid posting a second NOP if there is one already on the way. This way
we also avoid increasing the queue size (which might not help anyway).

Fixes: db05815b36 ("net/mlx5e: Add XSK zero-copy support")
Signed-off-by: Maxim Mikityanskiy <maximmi@mellanox.com>
Reviewed-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5.4-rM2-2.2.x-imx-squashed
Maxim Mikityanskiy 2020-02-11 16:02:35 +02:00 committed by Greg Kroah-Hartman
parent b4284efb1e
commit 2292e40490
4 changed files with 15 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
drivers/net/ethernet/mellanox/mlx5/core/en.h
View File

@ -367,6 +367,7 @@ enum {
MLX5E_SQ_STATE_AM,
MLX5E_SQ_STATE_TLS,
MLX5E_SQ_STATE_VLAN_NEED_L2_INLINE,
MLX5E_SQ_STATE_PENDING_XSK_TX,
};
struct mlx5e_sq_wqe_info {
@ -948,7 +949,7 @@ void mlx5e_page_release_dynamic(struct mlx5e_rq *rq,
void mlx5e_handle_rx_cqe(struct mlx5e_rq *rq, struct mlx5_cqe64 *cqe);
void mlx5e_handle_rx_cqe_mpwrq(struct mlx5e_rq *rq, struct mlx5_cqe64 *cqe);
bool mlx5e_post_rx_wqes(struct mlx5e_rq *rq);
void mlx5e_poll_ico_cq(struct mlx5e_cq *cq);
int mlx5e_poll_ico_cq(struct mlx5e_cq *cq);
bool mlx5e_post_rx_mpwqes(struct mlx5e_rq *rq);
void mlx5e_dealloc_rx_wqe(struct mlx5e_rq *rq, u16 ix);
void mlx5e_dealloc_rx_mpwqe(struct mlx5e_rq *rq, u16 ix);

3
drivers/net/ethernet/mellanox/mlx5/core/en/xsk/tx.c
View File

@ -33,6 +33,9 @@ int mlx5e_xsk_wakeup(struct net_device *dev, u32 qid, u32 flags)
if (unlikely(!test_bit(MLX5E_SQ_STATE_ENABLED, &c->xskicosq.state)))
return 0;
if (test_and_set_bit(MLX5E_SQ_STATE_PENDING_XSK_TX, &c->xskicosq.state))
return 0;
spin_lock(&c->xskicosq_lock);
mlx5e_trigger_irq(&c->xskicosq);
spin_unlock(&c->xskicosq_lock);

8
drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
View File

@ -587,7 +587,7 @@ bool mlx5e_post_rx_wqes(struct mlx5e_rq *rq)
return !!err;
}
void mlx5e_poll_ico_cq(struct mlx5e_cq *cq)
int mlx5e_poll_ico_cq(struct mlx5e_cq *cq)
{
struct mlx5e_icosq *sq = container_of(cq, struct mlx5e_icosq, cq);
struct mlx5_cqe64 *cqe;
@ -595,11 +595,11 @@ void mlx5e_poll_ico_cq(struct mlx5e_cq *cq)
int i;
if (unlikely(!test_bit(MLX5E_SQ_STATE_ENABLED, &sq->state)))
return;
return 0;
cqe = mlx5_cqwq_get_cqe(&cq->wq);
if (likely(!cqe))
return;
return 0;
/* sq->cc must be updated only after mlx5_cqwq_update_db_record(),
* otherwise a cq overrun may occur
@ -646,6 +646,8 @@ void mlx5e_poll_ico_cq(struct mlx5e_cq *cq)
sq->cc = sqcc;
mlx5_cqwq_update_db_record(&cq->wq);
return i;
}
bool mlx5e_post_rx_mpwqes(struct mlx5e_rq *rq)

6
drivers/net/ethernet/mellanox/mlx5/core/en_txrx.c
View File

@ -145,7 +145,11 @@ int mlx5e_napi_poll(struct napi_struct *napi, int budget)
busy |= rq->post_wqes(rq);
if (xsk_open) {
mlx5e_poll_ico_cq(&c->xskicosq.cq);
if (mlx5e_poll_ico_cq(&c->xskicosq.cq))
/* Don't clear the flag if nothing was polled to prevent
* queueing more WQEs and overflowing XSKICOSQ.
*/
clear_bit(MLX5E_SQ_STATE_PENDING_XSK_TX, &c->xskicosq.state);
busy |= mlx5e_poll_xdpsq_cq(&xsksq->cq);
busy_xsk |= mlx5e_napi_xsk_post(xsksq, xskrq);
}