| /* 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_helpers.h" |
| #include "bpf_tracing.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 = 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"; |
