[PATCH intel-net] ice: xsk: use Rx ring when picking NAPI context

[PATCH intel-net] ice: xsk: use Rx ring when picking NAPI context

[Maciej Fijalkowski]

Ice driver allocates per cpu XDP queues so that redirect path can safely
use smp_processor_id() as an index to the array. At the same time
though, XDP rings are used to pick NAPI context to call napi_schedule()
or set NAPIF_STATE_MISSED. When user reduces queue count, say to 8, and
num_possible_cpus() of underlying platform is 44, then this means queue
vectors with correlated NAPI contexts will carry several XDP queues.

This in turn can result in a broken behavior where NAPI context of
interest will never be scheduled and AF_XDP socket will not process any
traffic.

To fix this issue, use Rx ring to pull out the NAPI context.

Fixes: 2d4238f55697 ("ice: Add support for AF_XDP")
Fixes: 22bf877e528f ("ice: introduce XDP_TX fallback path")
Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
---
 drivers/net/ethernet/intel/ice/ice_xsk.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/intel/ice/ice_xsk.c b/drivers/net/ethernet/intel/ice/ice_xsk.c
index 49ba8bfdbf04..34d851d3e767 100644
--- a/drivers/net/ethernet/intel/ice/ice_xsk.c
+++ b/drivers/net/ethernet/intel/ice/ice_xsk.c
@@ -353,7 +353,7 @@ int ice_xsk_pool_setup(struct ice_vsi *vsi, struct xsk_buff_pool *pool, u16 qid)
 	if (if_running) {
 		ret = ice_qp_ena(vsi, qid);
 		if (!ret && pool_present)
-			napi_schedule(&vsi->xdp_rings[qid]->q_vector->napi);
+			napi_schedule(&vsi->rx_rings[qid]->q_vector->napi);
 		else if (ret)
 			netdev_err(vsi->netdev, "ice_qp_ena error = %d\n", ret);
 	}
@@ -936,7 +936,7 @@ ice_xsk_wakeup(struct net_device *netdev, u32 queue_id,
 	struct ice_netdev_priv *np = netdev_priv(netdev);
 	struct ice_q_vector *q_vector;
 	struct ice_vsi *vsi = np->vsi;
-	struct ice_tx_ring *ring;
+	struct ice_rx_ring *ring;
 
 	if (test_bit(ICE_VSI_DOWN, vsi->state))
 		return -ENETDOWN;
@@ -944,13 +944,13 @@ ice_xsk_wakeup(struct net_device *netdev, u32 queue_id,
 	if (!ice_is_xdp_ena_vsi(vsi))
 		return -EINVAL;
 
-	if (queue_id >= vsi->num_txq)
+	if (queue_id >= vsi->num_txq || queue_id >= vsi->num_rxq)
 		return -EINVAL;
 
 	if (!vsi->xdp_rings[queue_id]->xsk_pool)
 		return -EINVAL;
 
-	ring = vsi->xdp_rings[queue_id];
+	ring = vsi->rx_rings[queue_id];
 
 	/* The idea here is that if NAPI is running, mark a miss, so
 	 * it will run again. If not, trigger an interrupt and
-- 
2.27.0