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1// SPDX-License-Identifier: GPL-2.02/* Copyright (c) 2021 Facebook */3 4#include "vmlinux.h"5#include <bpf/bpf_helpers.h>6#include <bpf/bpf_tracing.h>7 8extern int LINUX_KERNEL_VERSION __kconfig;9/* this weak extern will be strict due to the other file's strong extern */10extern bool CONFIG_BPF_SYSCALL __kconfig __weak;11extern const void bpf_link_fops __ksym __weak;12 13int input_bss1;14int input_data1 = 1;15const volatile int input_rodata1 = 11;16 17int input_bss_weak __weak;18/* these two definitions should win */19int input_data_weak __weak = 10;20const volatile int input_rodata_weak __weak = 100;21 22extern int input_bss2;23extern int input_data2;24extern const int input_rodata2;25 26int output_bss1;27int output_data1;28int output_rodata1;29 30long output_sink1;31 32static __noinline int get_bss_res(void)33{34 /* just make sure all the relocations work against .text as well */35 return input_bss1 + input_bss2 + input_bss_weak;36}37 38SEC("raw_tp/sys_enter")39int BPF_PROG(handler1)40{41 output_bss1 = get_bss_res();42 output_data1 = input_data1 + input_data2 + input_data_weak;43 output_rodata1 = input_rodata1 + input_rodata2 + input_rodata_weak;44 45 /* make sure we actually use above special externs, otherwise compiler46 * will optimize them out47 */48 output_sink1 = LINUX_KERNEL_VERSION49 + CONFIG_BPF_SYSCALL50 + (long)&bpf_link_fops;51 return 0;52}53 54char LICENSE[] SEC("license") = "GPL";55