Commit 0bb4f9ec authored by Maciej Fijalkowski's avatar Maciej Fijalkowski Committed by Tony Nguyen
Browse files

ice: unify xdp_rings accesses 



There has been a long lasting issue of improper xdp_rings indexing for
XDP_TX and XDP_REDIRECT actions. Given that currently rx_ring->q_index
is mixed with smp_processor_id(), there could be a situation where Tx
descriptors are produced onto XDP Tx ring, but tail is never bumped -
for example pin a particular queue id to non-matching IRQ line.

Address this problem by ignoring the user ring count setting and always
initialize the xdp_rings array to be of num_possible_cpus() size. Then,
always use the smp_processor_id() as an index to xdp_rings array. This
provides serialization as at given time only a single softirq can run on
a particular CPU.

Signed-off-by: default avatarMaciej Fijalkowski <maciej.fijalkowski@intel.com>
Tested-by: default avatarGeorge Kuruvinakunnel <george.kuruvinakunnel@intel.com>
Signed-off-by: default avatarTony Nguyen <anthony.l.nguyen@intel.com>
parent e72bba21

drivers/net/ethernet/intel/ice/ice_lib.c

+1 −1
Original line number Diff line number Diff line
@@ -3215,7 +3215,7 @@ int ice_vsi_rebuild(struct ice_vsi *vsi, bool init_vsi) 


		ice_vsi_map_rings_to_vectors(vsi);

		if (ice_is_xdp_ena_vsi(vsi)) {

			vsi->num_xdp_txq = vsi->alloc_rxq;

			vsi->num_xdp_txq = num_possible_cpus();

			ret = ice_prepare_xdp_rings(vsi, vsi->xdp_prog);

			if (ret)

				goto err_vectors;

drivers/net/ethernet/intel/ice/ice_main.c

+1 −1
Original line number Diff line number Diff line
@@ -2638,7 +2638,7 @@ ice_xdp_setup_prog(struct ice_vsi *vsi, struct bpf_prog *prog, 
	}



	if (!ice_is_xdp_ena_vsi(vsi) && prog) {

		vsi->num_xdp_txq = vsi->alloc_rxq;

		vsi->num_xdp_txq = num_possible_cpus();

		xdp_ring_err = ice_prepare_xdp_rings(vsi, prog);

		if (xdp_ring_err)

			NL_SET_ERR_MSG_MOD(extack, "Setting up XDP Tx resources failed");

drivers/net/ethernet/intel/ice/ice_txrx_lib.c

+1 −1
Original line number Diff line number Diff line
@@ -297,7 +297,7 @@ void ice_finalize_xdp_rx(struct ice_rx_ring *rx_ring, unsigned int xdp_res) 


	if (xdp_res & ICE_XDP_TX) {

		struct ice_tx_ring *xdp_ring =

			rx_ring->vsi->xdp_rings[rx_ring->q_index];

			rx_ring->vsi->xdp_rings[smp_processor_id()];



		ice_xdp_ring_update_tail(xdp_ring);

	}