| 1 | // SPDX-License-Identifier: GPL-2.0 |
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| 2 | /* Copyright (c) 2021 Facebook */ |
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| 3 | |
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| 4 | #include "vmlinux.h" |
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| 5 | #include <bpf/bpf_helpers.h> |
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| 6 | #include <bpf/bpf_tracing.h> |
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| 7 | |
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| 8 | extern int LINUX_KERNEL_VERSION __kconfig; |
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| 9 | /* this weak extern will be strict due to the other file's strong extern */ |
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| 10 | extern bool CONFIG_BPF_SYSCALL __kconfig __weak; |
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| 11 | extern const void bpf_link_fops __ksym __weak; |
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| 12 | |
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| 13 | int input_bss1; |
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| 14 | int input_data1 = 1; |
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| 15 | const volatile int input_rodata1 = 11; |
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| 16 | |
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| 17 | int input_bss_weak __weak; |
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| 18 | /* these two definitions should win */ |
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| 19 | int input_data_weak __weak = 10; |
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| 20 | const volatile int input_rodata_weak __weak = 100; |
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| 21 | |
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| 22 | extern int input_bss2; |
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| 23 | extern int input_data2; |
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| 24 | extern const int input_rodata2; |
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| 25 | |
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| 26 | int output_bss1; |
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| 27 | int output_data1; |
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| 28 | int output_rodata1; |
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| 29 | |
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| 30 | long output_sink1; |
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| 31 | |
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| 32 | static __noinline int get_bss_res(void) |
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| 33 | { |
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| 34 | /* just make sure all the relocations work against .text as well */ |
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| 35 | return input_bss1 + input_bss2 + input_bss_weak; |
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| 36 | } |
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| 37 | |
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| 38 | SEC("raw_tp/sys_enter" ) |
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| 39 | int BPF_PROG(handler1) |
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| 40 | { |
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| 41 | output_bss1 = get_bss_res(); |
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| 42 | output_data1 = input_data1 + input_data2 + input_data_weak; |
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| 43 | output_rodata1 = input_rodata1 + input_rodata2 + input_rodata_weak; |
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| 44 | |
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| 45 | /* make sure we actually use above special externs, otherwise compiler |
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| 46 | * will optimize them out |
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| 47 | */ |
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| 48 | output_sink1 = LINUX_KERNEL_VERSION |
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| 49 | + CONFIG_BPF_SYSCALL |
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| 50 | + (long)&bpf_link_fops; |
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| 51 | return 0; |
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| 52 | } |
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| 53 | |
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| 54 | char LICENSE[] SEC("license" ) = "GPL" ; |
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| 55 | |
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