Re: [PATCH] selftests/tracing: Fix flakiness in trigger-hist-poll.tc by waiting for task exit

[Masami Hiramatsu (Google)]

On Thu, 29 Oct 2026 16:34:52 -0400, Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:
> On Tue, 21 Jul 2026 09:20:36 +0900
> 
> I'm finally getting around to looking at this!
> 
> "Masami Hiramatsu (Google)" <mhiramat@xxxxxxxxxx> wrote:
> 
> > diff --git a/tools/testing/selftests/ftrace/test.d/trigger/trigger-hist-poll.tc b/tools/testing/selftests/ftrace/test.d/trigger/trigger-hist-poll.tc
> > index 04eb8546fc07..d54d54f9ec77 100644
> > --- a/tools/testing/selftests/ftrace/test.d/trigger/trigger-hist-poll.tc
> > +++ b/tools/testing/selftests/ftrace/test.d/trigger/trigger-hist-poll.tc
> > @@ -38,11 +38,7 @@ BGPID=$!
> >  ${POLL} -I -t 4000 ${EVENT}/hist
> >  echo 0 > tracing_on
> >  
> > -if [ -d /proc/${BGPID} ]; then
> > -  echo "poll exits too soon"
> > -  kill -KILL ${BGPID} ||:
> > -  exit_fail
> > -fi
> > +wait ${BGPID} 2>/dev/null ||:
> >  
> >  if ! grep -qw "sleep" trace; then
> >    echo "poll exits before event happens"
> > @@ -60,11 +56,7 @@ BGPID=$!
> >  ${POLL} -P -t 4000 ${EVENT}/hist
> >  echo 0 > tracing_on
> >  
> > -if [ -d /proc/${BGPID} ]; then
> > -  echo "poll exits too soon"
> > -  kill -KILL ${BGPID} ||:
> > -  exit_fail
> > -fi
> > +wait ${BGPID} 2>/dev/null ||:
> >  
> >  if ! grep -qw "sleep" trace; then
> >    echo "poll exits before event happens"
> > @@ -72,3 +64,5 @@ if ! grep -qw "sleep" trace; then
> >  fi
> >  
> >  exit_pass
> > +
> > +
> 
> Hmm, any reason for the two added newlines here?

Oops, no reason. Maybe typo on the editor...

Thanks,

> 
> -- Steve
>

-- 
Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>