Re: [PATCH 3/3] selftests/ftrace: Use /bin/echo instead of built-in echo

[Masami Hiramatsu]

On Thu, 7 May 2020 09:12:07 -0400
Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:

> On Sat, 2 May 2020 12:08:42 +0900
> Masami Hiramatsu <mhiramat@xxxxxxxxxx> wrote:
> 
> > > > diff --git a/tools/testing/selftests/ftrace/test.d/trigger/trigger-trace-marker-hist.tc b/tools/testing/selftests/ftrace/test.d/trigger/trigger-trace-marker-hist.tc
> > > > index ab6bedb25736..b3f70f53ee69 100644
> > > > --- a/tools/testing/selftests/ftrace/test.d/trigger/trigger-trace-marker-hist.tc
> > > > +++ b/tools/testing/selftests/ftrace/test.d/trigger/trigger-trace-marker-hist.tc
> > > > @@ -30,7 +30,7 @@ fi
> > > >  
> > > >  echo "Test histogram trace_marker tigger"
> > > >  
> > > > -echo 'hist:keys=common_pid' > events/ftrace/print/trigger
> > > > +echo 'hist:keys=ip' > events/ftrace/print/trigger  
> > > 
> > > This is doing more than just changing the echo being used. It's changing
> > > the test being done.  
> > 
> > Yes, I need Tom's review for this change. As far as I can test, this
> > fixes the test failure. If this isn't acceptable, we can use "alias echo=echo"
> > for this test case.
> > 
> 
> I still don't see how changing "keys=common_pid" to "keys=ip" has anything
> to do with the echo patch. If that is a problem, it should be a different
> patch with explanation to why "keys=common_pid" is broken.

This test case uses a trace_marker event to make a histogram with
the common_pid key, and it expects the "echo" command is built-in command
so that the pid is same while writing several events to trace_marker.
I changed it to "ip" which is always same if trace_marker interface is
used.

Thank you,

> 
> -- Steve
> 


-- 
Masami Hiramatsu <mhiramat@xxxxxxxxxx>