Re: [RFC][v6][PATCH 8/9]: Define clone_with_pids() syscall

[Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>]

Arnd Bergmann [arnd@arndb.de] wrote:
| 
| I wonder if we can avoid spreading copies of this function across
| all architectures.
| 
| Would it be possible to define it like this?

Since this is a variant of clone() and clone is listed as a PTREGSCALL(),
I pass in the pt_regs.

arch/x86/kernel/entry_32.S lists clone() under this comment:

/*
 * System calls that need a pt_regs pointer.
 */

Is there a guideline on what system calls use/need pt_regs ?

Thanks,

Suakdev

| 
| asmlinkage long
| clone_with_pids(int flags, unsigned long child_stack_base, int __user *parent_tid_ptr,
|                        int __user *child_tid_ptr, struct pid_set __user *pid_setp)
| {
| 	if (!child_stack_base) {
| 		struct pt_regs *regs;
| 
| 		regs = task_pt_regs(current);
| 		child_stack_base = user_stack_pointer(regs);
| 	}
| 
| 	return do_fork_with_pids(clone_flags, child_stack_base, 0,
| 		parent_tid_ptr, child_tid_ptr, pid_setp);
| }