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1// SPDX-License-Identifier: GPL-2.02#include <linux/bpf.h>3#include <bpf/bpf_helpers.h>4#include <bpf/bpf_tracing.h>5 6int val = 0;7 8SEC("fentry/test_1")9int BPF_PROG(fentry_test_1, __u64 *st_ops_ctx)10{11 __u64 state;12 13 /* Read the traced st_ops arg1 which is a pointer */14 bpf_probe_read_kernel(&state, sizeof(__u64), (void *)st_ops_ctx);15 /* Read state->val */16 bpf_probe_read_kernel(&val, sizeof(__u32), (void *)state);17 18 return 0;19}20 21char _license[] SEC("license") = "GPL";22