Re: [RFC][v6][PATCH 0/9] clone_with_pids() syscall

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

| Also, if you're passing a struct, why not put nr_pids in there, and
| replace clone_pid_struct with a simple array? That would give us
| 
| struct clone_struct {
|         u64 flags;
|         u64 child_stack;
|         u32 child_tid;
|         u32 parent_tid;
| 	u32 nr_pids;
| 	u32 reserved1;
| 	u64 reserved2;
| };
| 
| int clone2(struct clone_struct *cs, pid_t *pids);

My only concern with this approach was the extra copy_from_user() in the
common case (i.e when not using the extended features).  I assume the
overhead of copy_from_user() is small enough to be ignored ?

Thanks,

Sukadev