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1// SPDX-License-Identifier: GPL-2.02// Copyright (c) 2019 Facebook3 4#include <linux/ptrace.h>5#include <linux/bpf.h>6#include <bpf/bpf_helpers.h>7#include <bpf/bpf_tracing.h>8 9struct {10 __uint(type, BPF_MAP_TYPE_ARRAY);11 __type(key, int);12 __type(value, int);13 __uint(max_entries, 1);14} my_pid_map SEC(".maps");15 16struct {17 __uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY);18 __type(key, int);19 __type(value, int);20} perf_buf_map SEC(".maps");21 22SEC("tp/raw_syscalls/sys_enter")23int handle_sys_enter(void *ctx)24{25 int zero = 0, *my_pid, cur_pid;26 int cpu = bpf_get_smp_processor_id();27 28 my_pid = bpf_map_lookup_elem(&my_pid_map, &zero);29 if (!my_pid)30 return 1;31 32 cur_pid = bpf_get_current_pid_tgid() >> 32;33 if (cur_pid != *my_pid)34 return 1;35 36 bpf_perf_event_output(ctx, &perf_buf_map, BPF_F_CURRENT_CPU,37 &cpu, sizeof(cpu));38 return 1;39}40 41char _license[] SEC("license") = "GPL";42