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1/* Copyright 2016 Netflix, Inc.2 *3 * This program is free software; you can redistribute it and/or4 * modify it under the terms of version 2 of the GNU General Public5 * License as published by the Free Software Foundation.6 */7#include <linux/ptrace.h>8#include <uapi/linux/bpf.h>9#include <uapi/linux/bpf_perf_event.h>10#include <bpf/bpf_helpers.h>11#include <bpf/bpf_tracing.h>12 13#define MAX_IPS 819214 15struct {16 __uint(type, BPF_MAP_TYPE_HASH);17 __type(key, u64);18 __type(value, u32);19 __uint(max_entries, MAX_IPS);20} ip_map SEC(".maps");21 22SEC("perf_event")23int do_sample(struct bpf_perf_event_data *ctx)24{25 u64 ip;26 u32 *value, init_val = 1;27 28 ip = PT_REGS_IP(&ctx->regs);29 value = bpf_map_lookup_elem(&ip_map, &ip);30 if (value)31 *value += 1;32 else33 /* E2BIG not tested for this example only */34 bpf_map_update_elem(&ip_map, &ip, &init_val, BPF_NOEXIST);35 36 return 0;37}38char _license[] SEC("license") = "GPL";39