Discussion on: How to add system call (syscall) that prints elapsed time of a process with given PID to the kernel and test it?

[Stalim Rivero]

I got this error:

arch/x86/entry/syscall_64.o:(.rodata+0x1120): undefined reference to `__64_sys_sys_petime'
Makefile:1080: recipe for target 'vmlinux' failed

[Nguyen Quang Duc]

change this in include/linux/syscalls.h
asmlinkage long sys_petime(int);
to:
asmlinkage long __64_sys_sys_petime(int);