1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright (c) 2016 John Fastabend <john.r.fastabend@intel.com>
5 #include <linux/if_link.h>
15 #include <sys/resource.h>
19 #include "bpf/libbpf.h"
21 static int ifindex_in;
22 static int ifindex_out;
23 static bool ifindex_out_xdp_dummy_attached = true;
25 static __u32 dummy_prog_id;
27 static __u32 xdp_flags = XDP_FLAGS_UPDATE_IF_NOEXIST;
28 static int rxcnt_map_fd;
30 static void int_exit(int sig)
32 __u32 curr_prog_id = 0;
34 if (bpf_get_link_xdp_id(ifindex_in, &curr_prog_id, xdp_flags)) {
35 printf("bpf_get_link_xdp_id failed\n");
38 if (prog_id == curr_prog_id)
39 bpf_set_link_xdp_fd(ifindex_in, -1, xdp_flags);
40 else if (!curr_prog_id)
41 printf("couldn't find a prog id on iface IN\n");
43 printf("program on iface IN changed, not removing\n");
45 if (ifindex_out_xdp_dummy_attached) {
47 if (bpf_get_link_xdp_id(ifindex_out, &curr_prog_id,
49 printf("bpf_get_link_xdp_id failed\n");
52 if (dummy_prog_id == curr_prog_id)
53 bpf_set_link_xdp_fd(ifindex_out, -1, xdp_flags);
54 else if (!curr_prog_id)
55 printf("couldn't find a prog id on iface OUT\n");
57 printf("program on iface OUT changed, not removing\n");
62 static void poll_stats(int interval, int ifindex)
64 unsigned int nr_cpus = bpf_num_possible_cpus();
65 __u64 values[nr_cpus], prev[nr_cpus];
67 memset(prev, 0, sizeof(prev));
75 assert(bpf_map_lookup_elem(rxcnt_map_fd, &key, values) == 0);
76 for (i = 0; i < nr_cpus; i++)
77 sum += (values[i] - prev[i]);
79 printf("ifindex %i: %10llu pkt/s\n",
80 ifindex, sum / interval);
81 memcpy(prev, values, sizeof(values));
85 static void usage(const char *prog)
88 "usage: %s [OPTS] IFINDEX_IN IFINDEX_OUT\n\n"
91 " -N enforce native mode\n"
92 " -F force loading prog\n",
97 int main(int argc, char **argv)
99 struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
100 struct bpf_prog_load_attr prog_load_attr = {
101 .prog_type = BPF_PROG_TYPE_XDP,
103 struct bpf_program *prog, *dummy_prog;
104 int prog_fd, tx_port_map_fd, opt;
105 struct bpf_prog_info info = {};
106 __u32 info_len = sizeof(info);
107 const char *optstr = "FSN";
108 struct bpf_object *obj;
113 while ((opt = getopt(argc, argv, optstr)) != -1) {
116 xdp_flags |= XDP_FLAGS_SKB_MODE;
119 xdp_flags |= XDP_FLAGS_DRV_MODE;
122 xdp_flags &= ~XDP_FLAGS_UPDATE_IF_NOEXIST;
125 usage(basename(argv[0]));
130 if (optind == argc) {
131 printf("usage: %s IFINDEX_IN IFINDEX_OUT\n", argv[0]);
135 if (setrlimit(RLIMIT_MEMLOCK, &r)) {
136 perror("setrlimit(RLIMIT_MEMLOCK)");
140 ifindex_in = strtoul(argv[optind], NULL, 0);
141 ifindex_out = strtoul(argv[optind + 1], NULL, 0);
142 printf("input: %d output: %d\n", ifindex_in, ifindex_out);
144 snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
145 prog_load_attr.file = filename;
147 if (bpf_prog_load_xattr(&prog_load_attr, &obj, &prog_fd))
150 prog = bpf_program__next(NULL, obj);
151 dummy_prog = bpf_program__next(prog, obj);
152 if (!prog || !dummy_prog) {
153 printf("finding a prog in obj file failed\n");
156 /* bpf_prog_load_xattr gives us the pointer to first prog's fd,
157 * so we're missing only the fd for dummy prog
159 dummy_prog_fd = bpf_program__fd(dummy_prog);
160 if (prog_fd < 0 || dummy_prog_fd < 0) {
161 printf("bpf_prog_load_xattr: %s\n", strerror(errno));
165 tx_port_map_fd = bpf_object__find_map_fd_by_name(obj, "tx_port");
166 rxcnt_map_fd = bpf_object__find_map_fd_by_name(obj, "rxcnt");
167 if (tx_port_map_fd < 0 || rxcnt_map_fd < 0) {
168 printf("bpf_object__find_map_fd_by_name failed\n");
172 if (bpf_set_link_xdp_fd(ifindex_in, prog_fd, xdp_flags) < 0) {
173 printf("ERROR: link set xdp fd failed on %d\n", ifindex_in);
177 ret = bpf_obj_get_info_by_fd(prog_fd, &info, &info_len);
179 printf("can't get prog info - %s\n", strerror(errno));
184 /* Loading dummy XDP prog on out-device */
185 if (bpf_set_link_xdp_fd(ifindex_out, dummy_prog_fd,
186 (xdp_flags | XDP_FLAGS_UPDATE_IF_NOEXIST)) < 0) {
187 printf("WARN: link set xdp fd failed on %d\n", ifindex_out);
188 ifindex_out_xdp_dummy_attached = false;
191 memset(&info, 0, sizeof(info));
192 ret = bpf_obj_get_info_by_fd(prog_fd, &info, &info_len);
194 printf("can't get prog info - %s\n", strerror(errno));
197 dummy_prog_id = info.id;
199 signal(SIGINT, int_exit);
200 signal(SIGTERM, int_exit);
202 /* bpf redirect port */
203 ret = bpf_map_update_elem(tx_port_map_fd, &key, &ifindex_out, 0);
205 perror("bpf_update_elem");
209 poll_stats(2, ifindex_out);