sx_sleep not waking up when timo expires

[Ian Lepore]

On Sat, 2018-07-28 at 18:01 -0700, John-Mark Gurney wrote:
> I recently upgraded my router to an Pine A64-LTS board, and have hit
> the same issue as PR 222126[1].  The solution at the end does not work
> for me, as I do not have that line in my loader.conf:
> kern.timecounter.smp_tsc_adjust=1
> 
> I have verified that the wake up does not happen, as I used a dtrace
> script to verify that pf_purge_expired_states is called or not called..
> When I change the timeout, pf will kick the thread and get things
> running again, but it has stopped a couple times later...
> 
> I'm running a recent SNAPSHOT:
> FreeBSD gate2.funkthat.com 12.0-CURRENT FreeBSD 12.0-CURRENT #0 r336134: Mon Jul  9 19:20:11 UTC 2018     root at releng3.nyi.freebsd.org:/usr/obj/usr/src/arm64.aarch64/sys/GENERIC  arm64
> 
> This is likely reproducable by just starting pf, even in a pass all
> mode, and watching for when the function stops getting called...  I'll
> see if I can't get an extermely minimal config to reproduce it.
> 
> Any suggestions?
> 
> [1] https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=222126
> 

Sounds like

 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=229644 

which has some patches attached which reduce but don't quite eliminate
the occurrances, so nothing has been committed yet. I just ordered a
SOPINE board so I can do some hands-on debugging.

-- Ian