> > > > - you seem to misuse uvmexp values in diff #2.
> > 
> > usually, swpgavail == swpages.
> 
> Oh, so it does! I looked too quickly at ddb "show uvmexp" it
> seems. Thanks. I guess this is relevant when swap is being detached?
> 
> The right number is then swpgavail - swpginuse.

no.  swpgavail - swpgonly.

> As long as that's non-zero,

As long as that's larger than TMPFS_PAGES_RESERVED,

YAMAMOTO Takashi