Resizing a LVM swap volume

Another post mainly for myself, just so I know where to find the information quickly the next time I need it. If you have swap on a LVM volume, these commands can be used to resize it (in this case, increase by 100MB):

swapoff /dev/vg_foo/lv_swap
lvextend -L+100M /dev/vg_foo/lv_swap
mkswap /dev/vg_foo/lv_swap
swapon /dev/vg_foo/lv_swap

That is: disable swapping on the volume, extend it, re-create the swap area and enable swapping again.