162306a36Sopenharmony_ci// SPDX-License-Identifier: GPL-2.0
262306a36Sopenharmony_ci/* Copyright (C) 2022. Huawei Technologies Co., Ltd */
362306a36Sopenharmony_ci#include <linux/bpf.h>
462306a36Sopenharmony_ci#include <bpf/bpf_helpers.h>
562306a36Sopenharmony_ci#include <bpf/bpf_tracing.h>
662306a36Sopenharmony_ci
762306a36Sopenharmony_cichar _license[] SEC("license") = "GPL";
862306a36Sopenharmony_ci
962306a36Sopenharmony_cistruct {
1062306a36Sopenharmony_ci	__uint(type, BPF_MAP_TYPE_HASH);
1162306a36Sopenharmony_ci	__uint(max_entries, 1);
1262306a36Sopenharmony_ci	__uint(key_size, sizeof(__u32));
1362306a36Sopenharmony_ci	__uint(value_size, sizeof(__u32));
1462306a36Sopenharmony_ci} htab SEC(".maps");
1562306a36Sopenharmony_ci
1662306a36Sopenharmony_ciint pid = 0;
1762306a36Sopenharmony_ciint update_err = 0;
1862306a36Sopenharmony_ci
1962306a36Sopenharmony_ciSEC("?fentry/lookup_elem_raw")
2062306a36Sopenharmony_ciint lookup_elem_raw(void *ctx)
2162306a36Sopenharmony_ci{
2262306a36Sopenharmony_ci	__u32 key = 0, value = 1;
2362306a36Sopenharmony_ci
2462306a36Sopenharmony_ci	if ((bpf_get_current_pid_tgid() >> 32) != pid)
2562306a36Sopenharmony_ci		return 0;
2662306a36Sopenharmony_ci
2762306a36Sopenharmony_ci	update_err = bpf_map_update_elem(&htab, &key, &value, 0);
2862306a36Sopenharmony_ci	return 0;
2962306a36Sopenharmony_ci}
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