[PATCH bpf-next v4 06/22] samples: bpf: Add BPF support for xdp_exception tracepoint
From: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Date: 2021-08-21 00:20:41
Also in:
netdev
Subsystem:
bpf [general] (safe dynamic programs and tools), the rest, xdp (express data path) · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, Linus Torvalds, David S. Miller, Jakub Kicinski, Jesper Dangaard Brouer, John Fastabend
This would allow us to store stats for each XDP action, including their per-CPU counts. Consolidating this here allows all redirect samples to detect xdp_exception events. Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> --- samples/bpf/xdp_sample.bpf.c | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+)
diff --git a/samples/bpf/xdp_sample.bpf.c b/samples/bpf/xdp_sample.bpf.c
index e22f2a97a988..53ab5a972405 100644
--- a/samples/bpf/xdp_sample.bpf.c
+++ b/samples/bpf/xdp_sample.bpf.c@@ -8,6 +8,7 @@ array_map rx_cnt SEC(".maps"); array_map redir_err_cnt SEC(".maps"); +array_map exception_cnt SEC(".maps"); const volatile int nr_cpus = 0;
@@ -110,3 +111,29 @@ int BPF_PROG(tp_xdp_redirect_map, const struct net_device *dev, { return xdp_redirect_collect_stat(dev->ifindex, err); } + +SEC("tp_btf/xdp_exception") +int BPF_PROG(tp_xdp_exception, const struct net_device *dev, + const struct bpf_prog *xdp, u32 act) +{ + u32 cpu = bpf_get_smp_processor_id(); + struct datarec *rec; + u32 key = act, idx; + + if (!IN_SET(from_match, dev->ifindex)) + return 0; + if (!IN_SET(to_match, dev->ifindex)) + return 0; + + if (key > XDP_REDIRECT) + key = XDP_REDIRECT + 1; + + idx = key * nr_cpus + cpu; + rec = bpf_map_lookup_elem(&exception_cnt, &idx); + if (!rec) + return 0; + NO_TEAR_INC(rec->dropped); + + return 0; +} +
--
2.33.0