Solved Live extend gpt

Hi, I new to live resize a gpt+zfs partition.

But, the free size is invisible to GPT.

Camcontrol OK (original size is 20G) :

# camcontrol readcap da0 -h
Device Size: 40 G, Block Length: 512 bytes

But gpt :
# gpart show da0
=>      34  41942973  da0  GPT  (20G)
        34      1024    1  freebsd-boot  (512K)
      1058   4194304    2  freebsd-swap  (2.0G)
   4195362  37747645    3  freebsd-zfs  (18G)

What can I do without rebooting ?

Thanks you
First check that FreeBSD received resize event for the disk checking geom disk list da0. If yes, then use gpart resize -i 3 da0. After that read about ZFS autoexpand.