diff options
Diffstat (limited to 'samples/bpf/xdp_sample_pkts_user.c')
| -rw-r--r-- | samples/bpf/xdp_sample_pkts_user.c | 34 |
1 files changed, 29 insertions, 5 deletions
diff --git a/samples/bpf/xdp_sample_pkts_user.c b/samples/bpf/xdp_sample_pkts_user.c index 62f34827c775..dc66345a929a 100644 --- a/samples/bpf/xdp_sample_pkts_user.c +++ b/samples/bpf/xdp_sample_pkts_user.c @@ -24,25 +24,49 @@ static int pmu_fds[MAX_CPUS], if_idx; static struct perf_event_mmap_page *headers[MAX_CPUS]; static char *if_name; static __u32 xdp_flags = XDP_FLAGS_UPDATE_IF_NOEXIST; +static __u32 prog_id; static int do_attach(int idx, int fd, const char *name) { + struct bpf_prog_info info = {}; + __u32 info_len = sizeof(info); int err; err = bpf_set_link_xdp_fd(idx, fd, xdp_flags); - if (err < 0) + if (err < 0) { printf("ERROR: failed to attach program to %s\n", name); + return err; + } + + err = bpf_obj_get_info_by_fd(fd, &info, &info_len); + if (err) { + printf("can't get prog info - %s\n", strerror(errno)); + return err; + } + prog_id = info.id; return err; } static int do_detach(int idx, const char *name) { - int err; + __u32 curr_prog_id = 0; + int err = 0; - err = bpf_set_link_xdp_fd(idx, -1, 0); - if (err < 0) - printf("ERROR: failed to detach program from %s\n", name); + err = bpf_get_link_xdp_id(idx, &curr_prog_id, 0); + if (err) { + printf("bpf_get_link_xdp_id failed\n"); + return err; + } + if (prog_id == curr_prog_id) { + err = bpf_set_link_xdp_fd(idx, -1, 0); + if (err < 0) + printf("ERROR: failed to detach prog from %s\n", name); + } else if (!curr_prog_id) { + printf("couldn't find a prog id on a %s\n", name); + } else { + printf("program on interface changed, not removing\n"); + } return err; } |