From 0bd5ab511e30a8c462c377d0fdda3374fc6200a4 Mon Sep 17 00:00:00 2001 From: Maciej Fijalkowski Date: Wed, 13 Apr 2022 17:30:04 +0200 Subject: [PATCH] ice, xsk: Decorate ICE_XDP_REDIR with likely() ice_run_xdp_zc() suggests to compiler that XDP_REDIRECT is the most probable action returned from BPF program that AF_XDP has in its pipeline. Let's also bring this suggestion up to the callsite of ice_run_xdp_zc() so that compiler will be able to generate more optimized code which in turn will make branch predictor happy. Suggested-by: Jesper Dangaard Brouer Signed-off-by: Maciej Fijalkowski Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20220413153015.453864-4-maciej.fijalkowski@intel.com --- drivers/net/ethernet/intel/ice/ice_xsk.c | 21 +++++++++++---------- 1 file changed, 11 insertions(+), 10 deletions(-) diff --git a/drivers/net/ethernet/intel/ice/ice_xsk.c b/drivers/net/ethernet/intel/ice/ice_xsk.c index 866ee4d..e9ff05d 100644 --- a/drivers/net/ethernet/intel/ice/ice_xsk.c +++ b/drivers/net/ethernet/intel/ice/ice_xsk.c @@ -629,18 +629,19 @@ int ice_clean_rx_irq_zc(struct ice_rx_ring *rx_ring, int budget) xsk_buff_dma_sync_for_cpu(xdp, rx_ring->xsk_pool); xdp_res = ice_run_xdp_zc(rx_ring, xdp, xdp_prog, xdp_ring); - if (xdp_res) { - if (xdp_res & (ICE_XDP_TX | ICE_XDP_REDIR)) - xdp_xmit |= xdp_res; - else - xsk_buff_free(xdp); + if (likely(xdp_res & (ICE_XDP_TX | ICE_XDP_REDIR))) + xdp_xmit |= xdp_res; + else if (xdp_res == ICE_XDP_CONSUMED) + xsk_buff_free(xdp); + else + goto construct_skb; - total_rx_bytes += size; - total_rx_packets++; + total_rx_bytes += size; + total_rx_packets++; + + ice_bump_ntc(rx_ring); + continue; - ice_bump_ntc(rx_ring); - continue; - } construct_skb: /* XDP_PASS path */ skb = ice_construct_skb_zc(rx_ring, xdp); -- 2.7.4