Re: [Intel-wired-lan] [PATCH v2 iwl-net 3/8] ice: replace synchronize_rcu with synchronize_net

[Nelson, Shannon]

On 5/29/2024 4:23 AM, Maciej Fijalkowski wrote:

Given that ice_qp_dis() is called under rtnl_lock, synchronize_net() can
be called instead of synchronize_rcu() so that XDP rings can finish its
job in a faster way. Also let us do this as earlier in XSK queue disable
flow.

Additionally, turn off regular Tx queue before disabling irqs and NAPI.

Fixes: 2d4238f55697 ("ice: Add support for AF_XDP")
Signed-off-by: Maciej Fijalkowski <maciej.fijalkow...@intel.com>
---
  drivers/net/ethernet/intel/ice/ice_xsk.c | 6 +++---
  1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/intel/ice/ice_xsk.c 
b/drivers/net/ethernet/intel/ice/ice_xsk.c
index 4f606a1055b0..e93cb0ca4106 100644
--- a/drivers/net/ethernet/intel/ice/ice_xsk.c
+++ b/drivers/net/ethernet/intel/ice/ice_xsk.c
@@ -53,7 +53,6 @@ static void ice_qp_clean_rings(struct ice_vsi *vsi, u16 q_idx)
  {
         ice_clean_tx_ring(vsi->tx_rings[q_idx]);
         if (ice_is_xdp_ena_vsi(vsi)) {
-               synchronize_rcu();
                 ice_clean_tx_ring(vsi->xdp_rings[q_idx]);
         }

With only one statement left in the block you'll probably want to remove 
the {}'s

sln


         ice_clean_rx_ring(vsi->rx_rings[q_idx]);
@@ -180,11 +179,12 @@ static int ice_qp_dis(struct ice_vsi *vsi, u16 q_idx)
                 usleep_range(1000, 2000);
         }

+       synchronize_net();
+       netif_tx_stop_queue(netdev_get_tx_queue(vsi->netdev, q_idx));
+
         ice_qvec_dis_irq(vsi, rx_ring, q_vector);
         ice_qvec_toggle_napi(vsi, q_vector, false);

-       netif_tx_stop_queue(netdev_get_tx_queue(vsi->netdev, q_idx));
-
         ice_fill_txq_meta(vsi, tx_ring, &txq_meta);
         err = ice_vsi_stop_tx_ring(vsi, ICE_NO_RESET, 0, tx_ring, &txq_meta);
         if (err)
--
2.34.1