| /* 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 <linux/version.h> |
| #include <linux/ptrace.h> |
| #include <uapi/linux/bpf.h> |
| #include <uapi/linux/bpf_perf_event.h> |
| #include <bpf/bpf_helpers.h> |
| #include <bpf/bpf_tracing.h> |
| |
| #define MAX_IPS 8192 |
| |
| struct { |
| __uint(type, BPF_MAP_TYPE_HASH); |
| __type(key, u64); |
| __type(value, u32); |
| __uint(max_entries, MAX_IPS); |
| } ip_map SEC(".maps"); |
| |
| SEC("perf_event") |
| int do_sample(struct bpf_perf_event_data *ctx) |
| { |
| u64 ip; |
| u32 *value, init_val = 1; |
| |
| ip = PT_REGS_IP(&ctx->regs); |
| 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"; |
