[gentoo-embedded] glibc fails in upgrade

I just ran emerge -avuND @world my RPI3 and my build crashed when it tried
to merge glibc with this error "structure needs cleaning".I found some
instructions on how to fix it *here
<https://www.reddit.com/r/linuxquestions/comments/4b47r2/has_anyone_ever_gotten_structure_needs_cleaning/>*.
However, when I got to the part where I needed to fsck I received an error
that the filesystem is mounted. Do I need to turn off the pi and place the
SD card on my laptop to fix?

Thanks
Herminio