Messages in this thread | | | Date | Mon, 26 Oct 2009 05:38:54 -0400 | Subject | Re: [RFC][v8][PATCH 0/10] Implement clone3() system call | From | Albert Cahalan <> |
| |
Sukadev Bhattiprolu writes:
> struct clone_struct { > u64 flags; > u64 child_stack; > u32 nr_pids; > u32 reserved1; > u64 parent_tid; > u64 child_tid; > u64 reserved2; > }; > > sys_clone3(struct clone_struct __user *cs, pid_t __user *pids)
We'll be needing a clone4() for ia64 if you don't include the stack_size parameter.
You have a prime opportunity to fix a portability problem that has been quite a pain for some time. There are currently 3 cases that userspace has to suffer with:
1. specify one end of the stack with clone 2. specify the other end of the stack with clone (HP PA-RISC) 3. specify the base and size with clone2 (IA-64)
Portable code ends up with an icky #ifdef mess.
BTW, the extra stack info is also useful for other purposes. It's information that could appear in /proc/*/maps data. With an extra flag, thread stacks could be freed on thread exit so that other threads don't have to babysit an exiting thread.
| |