40 lines
942 B
C
40 lines
942 B
C
/* Copyright 2016 Netflix, Inc.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of version 2 of the GNU General Public
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* License as published by the Free Software Foundation.
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*/
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#include <linux/version.h>
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#include <linux/ptrace.h>
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#include <uapi/linux/bpf.h>
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#include <uapi/linux/bpf_perf_event.h>
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#include <bpf/bpf_helpers.h>
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#include <bpf/bpf_tracing.h>
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#define MAX_IPS 8192
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struct {
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__uint(type, BPF_MAP_TYPE_HASH);
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__type(key, u64);
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__type(value, u32);
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__uint(max_entries, MAX_IPS);
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} ip_map SEC(".maps");
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SEC("perf_event")
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int do_sample(struct bpf_perf_event_data *ctx)
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{
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u64 ip;
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u32 *value, init_val = 1;
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ip = PT_REGS_IP(&ctx->regs);
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value = bpf_map_lookup_elem(&ip_map, &ip);
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if (value)
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*value += 1;
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else
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/* E2BIG not tested for this example only */
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bpf_map_update_elem(&ip_map, &ip, &init_val, BPF_NOEXIST);
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return 0;
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}
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char _license[] SEC("license") = "GPL";
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