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arch/x86/entry/syscall_64.c

System call table for x86-64
This file includes arch/x86/include/generated/asm/syscalls_64.h twice, with different definitions for __SYSCALL: 
#define __SYSCALL(nr, sym) extern long __x64_##sym(const struct pt_regs *);
#include <asm/syscalls_64.h>
#undef __SYSCALL

#define __SYSCALL(nr, sym) __x64_##sym,
asmlinkage const sys_call_ptr_t sys_call_table[] = {
#include <asm/syscalls_64.h>
}

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