Trying to use XDP hardware offloading via XDP_FLAGS_HW_MODE and setting the ifindex in prog_load_attr.ifindex before loading the BPF code via bpf_prog_load_xattr().
This unfortunately does not seem to work... - Am I doing something wrong? Notice, I also disable the map BPF_MAP_TYPE_PERCPU_ARRAY to make sure it was not related to the map (not supporting offloading). Failed with: # ./xdp1 -O $(</sys/class/net/enp130s0np1/ifindex) libbpf: load bpf program failed: Invalid argument libbpf: failed to load program 'xdp1' libbpf: failed to load object './xdp1_kern.o' Tested on kernel 4.18.0-2.el8.x86_64 with driver nfp Ethernet controller: Netronome Systems, Inc. Device 4000 --- samples/bpf/xdp1_kern.c | 8 +++++--- samples/bpf/xdp1_user.c | 12 ++++++++++-- 2 files changed, 15 insertions(+), 5 deletions(-) diff --git a/samples/bpf/xdp1_kern.c b/samples/bpf/xdp1_kern.c index 219742106bfd..1b577b7dba1e 100644 --- a/samples/bpf/xdp1_kern.c +++ b/samples/bpf/xdp1_kern.c @@ -14,12 +14,14 @@ #include <linux/ipv6.h> #include "bpf_helpers.h" +/* struct bpf_map_def SEC("maps") rxcnt = { .type = BPF_MAP_TYPE_PERCPU_ARRAY, .key_size = sizeof(u32), .value_size = sizeof(long), .max_entries = 256, }; +*/ static int parse_ipv4(void *data, u64 nh_off, void *data_end) { @@ -83,9 +85,9 @@ int xdp_prog1(struct xdp_md *ctx) else ipproto = 0; - value = bpf_map_lookup_elem(&rxcnt, &ipproto); - if (value) - *value += 1; +// value = bpf_map_lookup_elem(&rxcnt, &ipproto); +// if (value) +// *value += 1; return rc; } diff --git a/samples/bpf/xdp1_user.c b/samples/bpf/xdp1_user.c index b02c531510ed..a362b5adfcf0 100644 --- a/samples/bpf/xdp1_user.c +++ b/samples/bpf/xdp1_user.c @@ -64,7 +64,8 @@ static void usage(const char *prog) "usage: %s [OPTS] IFINDEX\n\n" "OPTS:\n" " -S use skb-mode\n" - " -N enforce native mode\n", + " -N enforce native mode\n" + " -O offload mode\n", prog); } @@ -74,7 +75,7 @@ int main(int argc, char **argv) struct bpf_prog_load_attr prog_load_attr = { .prog_type = BPF_PROG_TYPE_XDP, }; - const char *optstr = "SN"; + const char *optstr = "SNO"; int prog_fd, map_fd, opt; struct bpf_object *obj; struct bpf_map *map; @@ -88,6 +89,9 @@ int main(int argc, char **argv) case 'N': xdp_flags |= XDP_FLAGS_DRV_MODE; break; + case 'O': + xdp_flags |= XDP_FLAGS_HW_MODE; + break; default: usage(basename(argv[0])); return 1; @@ -109,6 +113,10 @@ int main(int argc, char **argv) snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]); prog_load_attr.file = filename; + /* For HW offload provide ifindex when loading BPF code */ + if (xdp_flags & XDP_FLAGS_HW_MODE) { + prog_load_attr.ifindex = ifindex; + } if (bpf_prog_load_xattr(&prog_load_attr, &obj, &prog_fd)) return 1;