bin/165207: rctl(8) cannot identify jails via modified name

[Brent]

>Number:         165207
>Category:       bin
>Synopsis:       rctl(8) cannot identify jails via modified name
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Thu Feb 16 17:20:09 UTC 2012
>Closed-Date:
>Last-Modified:
>Originator:     Brent
>Release:        9.0-RELEASE
>Organization:
>Environment:
FreeBSD freebsd 9.0-RELEASE FreeBSD 9.0-RELEASE #0: Tue Feb 14 11:01:47 EST 2012     root at freebsd:/usr/obj/usr/src/sys/RCTL  amd64
>Description:
rctl(8) man page examples state:

           rctl -hu jail:www

     Display resource usage information for jail named "www".

If a jail is started with -n "name", rctl can correctly identify it. If a running jail's name is modified with `jail -m name="name"`, rctl cannot identify it, and continues to use the previous jail name. If no jail name was set upon jail creation, rctl can only identify it via its JID.
>How-To-Repeat:
JID 5 was started with -n "test1":

freebsd# jls
   JID  IP Address      Hostname                      Path
     5  10.1.1.1        test1                         /usr/jails/test1

Accessible via name:
freebsd# jexec test1 tcsh
test1#

Show stats for jail named "test1":
freebsd# rctl -hu jail:test1|head
cputime=1681
datasize=16M
stacksize=0
coredumpsize=0
memoryuse=57M
memorylocked=0
maxproc=10
openfiles=0
vmemoryuse=937M
pseudoterminals=0

Modify jail name to "test2":
freebsd# jail -m name=test2 jid=5

Accessible via modified name "test2":
freebsd# jexec test2 tcsh
test1#

`rctl` has no knowledge of "test2":
freebsd# rctl -hu jail:test2|head
cputime=0
datasize=0
stacksize=0
coredumpsize=0
memoryuse=0
memorylocked=0
maxproc=0
openfiles=0
vmemoryuse=0
pseudoterminals=0

`rctl` still believes it's "test1":
freebsd# rctl -hu jail:test1|head
cputime=1900
datasize=16M
stacksize=0
coredumpsize=0
memoryuse=57M
memorylocked=0
maxproc=10
openfiles=0
vmemoryuse=937M
pseudoterminals=0
>Fix:


>Release-Note:
>Audit-Trail:
>Unformatted: