| /* 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" | |
| #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"; |