[LTP] [PATCH] memcg/functional: check several times if the process is killed

[Cyril Hrubis <chrubis@suse.cz>]

Hi!
> > > > We should better change this for something more robust. Given that the
> > > > memgc_progcess does while (!flag_exit) sleep(1); in the main loop we may
> > > > as well wait till the process gets into the sleep state.
> > > >
> > > 
> > > I don't understand why it's more robust. For example, a process can get
> > > into the sleep state (interruptible sleep) due to a call to a syscall, no?
> > 
> > Generally yes, but in this case it's unlikely that opening /dev/zero or
> > calling sigaction() would block.
> 
> There's also some ld setup going on before that. Opening/mapping/reading
> various config and .so files.

Ah right, I tend to forgot that part.

> > > So maybe keep this sleep() as is?
> > 
> > I'm Ok with that one as well. But we should rethink and fix it later.
> 
> My immediate idea was to let memcg_process open "/tmp/memcg_process_ready"
> and shell script would monitor /proc/$pid/fd/ until sees that or hits timeout.

Or we can reuse the checkpoint library, given that the memory is now
backed by tmpfs and path to the file si passed in environment it should
be relatively easy to write a helper binary so that we can use it from
the shell as well.

-- 
Cyril Hrubis
chrubis@suse.cz