Hi,

Now I've really attached the lockless receive patch. The previous patch 
[that I forgot to attach] was buggy, attached is an updated and tested 
patch:

Description:
- General cleanup of sys_msgrcv and sys_msgsnd: the function were too 
convoluted.
- Enable lockless receive, update comments.
- Use ipc_getref for sys_msgsnd(), it's better than rechecking that the 
msqid is still valid.

Signed-Off-By: Manfred Spraul <manfred@colorfullife.com>