From 72874418e4b9e2673c26a810b0ae9f418b573ee3 Mon Sep 17 00:00:00 2001 From: Brendan Gregg Date: Thu, 1 Sep 2016 18:37:26 -0700 Subject: samples/bpf: add sampleip example sample instruction pointer and frequency count in a BPF map Signed-off-by: Brendan Gregg Signed-off-by: Alexei Starovoitov Signed-off-by: David S. Miller --- samples/bpf/sampleip_kern.c | 38 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 38 insertions(+) create mode 100644 samples/bpf/sampleip_kern.c (limited to 'samples/bpf/sampleip_kern.c') diff --git a/samples/bpf/sampleip_kern.c b/samples/bpf/sampleip_kern.c new file mode 100644 index 000000000000..774a681f374a --- /dev/null +++ b/samples/bpf/sampleip_kern.c @@ -0,0 +1,38 @@ +/* Copyright 2016 Netflix, Inc. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of version 2 of the GNU General Public + * License as published by the Free Software Foundation. + */ +#include +#include +#include +#include +#include "bpf_helpers.h" + +#define MAX_IPS 8192 + +struct bpf_map_def SEC("maps") ip_map = { + .type = BPF_MAP_TYPE_HASH, + .key_size = sizeof(u64), + .value_size = sizeof(u32), + .max_entries = MAX_IPS, +}; + +SEC("perf_event") +int do_sample(struct bpf_perf_event_data *ctx) +{ + u64 ip; + u32 *value, init_val = 1; + + ip = ctx->regs.ip; + value = bpf_map_lookup_elem(&ip_map, &ip); + if (value) + *value += 1; + else + /* E2BIG not tested for this example only */ + bpf_map_update_elem(&ip_map, &ip, &init_val, BPF_NOEXIST); + + return 0; +} +char _license[] SEC("license") = "GPL"; -- cgit