From e1302542e37ebbc1de70982e93bd777397f90712 Mon Sep 17 00:00:00 2001 From: Jesper Dangaard Brouer Date: Mon, 3 Sep 2018 09:54:57 +0200 Subject: [PATCH] xdp: unlikely instrumentation for xdp map redirect Notice the compiler generated ASM code layout was suboptimal. It assumed map enqueue errors as the likely case, which is shouldn't. It assumed that xdp_do_flush_map() was a likely case, due to maps changing between packets, which should be very unlikely. Signed-off-by: Jesper Dangaard Brouer Signed-off-by: Alexei Starovoitov --- net/core/filter.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/net/core/filter.c b/net/core/filter.c index d301134bca3a..80200f719028 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -3187,7 +3187,7 @@ static int __bpf_tx_xdp_map(struct net_device *dev_rx, void *fwd, struct bpf_dtab_netdev *dst = fwd; err = dev_map_enqueue(dst, xdp, dev_rx); - if (err) + if (unlikely(err)) return err; __dev_map_insert_ctx(map, index); break; @@ -3196,7 +3196,7 @@ static int __bpf_tx_xdp_map(struct net_device *dev_rx, void *fwd, struct bpf_cpu_map_entry *rcpu = fwd; err = cpu_map_enqueue(rcpu, xdp, dev_rx); - if (err) + if (unlikely(err)) return err; __cpu_map_insert_ctx(map, index); break; @@ -3284,7 +3284,7 @@ static int xdp_do_redirect_map(struct net_device *dev, struct xdp_buff *xdp, err = -EINVAL; goto err; } - if (ri->map_to_flush && ri->map_to_flush != map) + if (ri->map_to_flush && unlikely(ri->map_to_flush != map)) xdp_do_flush_map(); err = __bpf_tx_xdp_map(dev, fwd, map, xdp, index); -- GitLab