Re: [kvm-unit-tests PATCH 2/3] migration: Fix test harness hang if source does not reach migration point

["Nicholas Piggin" <npiggin@gmail.com>]

On Fri Jul 28, 2023 at 5:34 PM AEST, Nico Boehr wrote:
> Quoting Nicholas Piggin (2023-07-25 05:39:36)
> > After starting the test, the harness waits polling for "migrate" in the
> > output. If the test does not print for some reason, the harness hangs.
> > 
> > Test that the pid is still alive while polling to fix this hang.
> > 
> > While here, wait for the full string "Now migrate the VM", which I think
> > makes it more obvious to read and could avoid an unfortunate collision
> > with some debugging output in a test case.
> > 
> > Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
>
> Thanks for attempting to fix this!
>
> > ---
> >  scripts/arch-run.bash | 10 +++++++++-
> >  1 file changed, 9 insertions(+), 1 deletion(-)
> > 
> > diff --git a/scripts/arch-run.bash b/scripts/arch-run.bash
> > index 518607f4..30e535c7 100644
> > --- a/scripts/arch-run.bash
> > +++ b/scripts/arch-run.bash
> > @@ -142,6 +142,7 @@ run_migration ()
> >  
> >         eval "$@" -chardev socket,id=mon1,path=${qmp1},server=on,wait=off \
> >                 -mon chardev=mon1,mode=control | tee ${migout1} &
> > +       live_pid=`jobs -l %+ | grep "eval" | awk '{print$2}'`
>
> Pardon my ignorance, but why would $! not work here?

My mastery of bash is poor, I copied the incoming_pid line. It seems
to work, but if you think $! is better I can try it.

Thanks,
Nick