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| author | Jesper Dangaard Brouer <brouer@redhat.com> | 2017-10-06 10:41:41 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-10-06 10:04:35 -0700 |
| commit | f4ce0a0116bc90803adac10865f14429313cb2b6 (patch) | |
| tree | 7cfb55bafa296fcadaf5c6a88582293ceb8c0c30 /samples/bpf | |
| parent | c6a157525be5b6cab48b4c86e7473712e3656c36 (diff) | |
| download | linux-f4ce0a0116bc90803adac10865f14429313cb2b6.tar.gz linux-f4ce0a0116bc90803adac10865f14429313cb2b6.tar.bz2 linux-f4ce0a0116bc90803adac10865f14429313cb2b6.zip | |
samples/bpf: xdp_monitor first 8 bytes are not accessible by bpf
The first 8 bytes of the tracepoint context struct are not accessible
by the bpf code. This is a choice that dates back to the original
inclusion of this code.
See explaination in:
commit 98b5c2c65c29 ("perf, bpf: allow bpf programs attach to tracepoints")
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'samples/bpf')
| -rw-r--r-- | samples/bpf/xdp_monitor_kern.c | 22 |
1 files changed, 9 insertions, 13 deletions
diff --git a/samples/bpf/xdp_monitor_kern.c b/samples/bpf/xdp_monitor_kern.c index 74f3fd8ed729..cc7e19d2ad76 100644 --- a/samples/bpf/xdp_monitor_kern.c +++ b/samples/bpf/xdp_monitor_kern.c @@ -17,19 +17,15 @@ struct bpf_map_def SEC("maps") redirect_err_cnt = { * Code in: kernel/include/trace/events/xdp.h */ struct xdp_redirect_ctx { - unsigned short common_type; // offset:0; size:2; signed:0; - unsigned char common_flags; // offset:2; size:1; signed:0; - unsigned char common_preempt_count;// offset:3; size:1; signed:0; - int common_pid; // offset:4; size:4; signed:1; - - int prog_id; // offset:8; size:4; signed:1; - u32 act; // offset:12 size:4; signed:0; - int ifindex; // offset:16 size:4; signed:1; - int err; // offset:20 size:4; signed:1; - int to_ifindex; // offset:24 size:4; signed:1; - u32 map_id; // offset:28 size:4; signed:0; - int map_index; // offset:32 size:4; signed:1; -}; // offset:36 + u64 __pad; // First 8 bytes are not accessible by bpf code + int prog_id; // offset:8; size:4; signed:1; + u32 act; // offset:12 size:4; signed:0; + int ifindex; // offset:16 size:4; signed:1; + int err; // offset:20 size:4; signed:1; + int to_ifindex; // offset:24 size:4; signed:1; + u32 map_id; // offset:28 size:4; signed:0; + int map_index; // offset:32 size:4; signed:1; +}; // offset:36 enum { XDP_REDIRECT_SUCCESS = 0, |