Re: [PATCH v7 00/16] tracing: Hist trigger snapshot and onchange additions

Masami Hiramatsu
2018-11-29T13:52:32Z

On Mon, 26 Nov 2018 15:21:28 -0600
Tom Zanussi <zanussi@kernel.org> wrote:

> Hi Masami,
>
> On Mon, 2018-11-26 at 23:09 +0900, Masami Hiramatsu wrote:
> > Hi Tom,
> >
> > On Wed, 14 Nov 2018 14:17:57 -0600
> > Tom Zanussi <zanussi@kernel.org> wrote:
> >
> > > From: Tom Zanussi <tom.zanussi@linux.intel.com>
> > >
> > > Hi,
> > >
> > > This is v7 of the hist trigger snapshot and onchange additions
> > > patchset. It does a bit of refactoring to address the suggestions
> > > made by Masami in v6.
> >
> > Thank you for fixing it.
> >
> > >
> > > It also adds an additional patch to update the trigger/inter-event
> > > testcases with SPDX license blurbs.
> > >
> > > BTW, I noticed that with the recent kselftest changes, I now get
> > > mangled output when running the selftests, though I can still see
> > > well
> > > enough that the tests passed as expected. This happens with any of
> > > the ftrace selftests and not just the trigger selftests. In my
> > > case,
> > > this is using the stock Terminal in Ubuntu 17.10, in case that
> > > helps.
> >
> > Hmm, it should be fixed by
> > 8096fbcf55c0 ("selftests/ftrace: Use colored output when available")
> >
> > Could you check your kernel has this commit?
> >
>
> Yes, it does have this commit.
>
> > BTW, what terminal and environment (especially echo command)
> > did you run your tests on? (It seems echo command didn't accept -e
> > option)
> >
>
> For that system, I'm using Gnome terminal 3.24.2 and GNU bash, version
> 4.4.12(1)-release (x86_64-pc-linux-gnu) (Ubuntu 17.10).
>
> If I change 'echo' to '/bin/echo' in e.g. prlog() it works fine, so it
> must be the inbuilt bash echo that's not doing the right thing. I
> thought it might be the xpg_echo option, but 'shopt -s xpg_echo'
> doesn't have any effect.
>
> I also tried on a Fedora 28 system (GNOME terminal 3.28.2, GNU bash,
> version 4.4.23(1)-release (x86_64-redhat-linux-gnu), and it worked
> fine.
>
> Also, tried a Ubuntu 18.04.1 system (GNOME Terminal 3.28.1, GNU bash,
> version 4.4.19(1)-release (x86_64-pc-linux-gnu) and in that case the
> colors worked fine, but still got the '-e -n' and newlines in the
> output:
>
> -e -n [28] (instance) event trigger - test histogram modifiers
> -e [PASS]
> -e -n [29] (instance) event trigger - test histogram trigger
> -e [PASS]
>
> Again, substituting '/bin/echo' in prlog() fixed things in this case
> too. I guess the builtin bash 'echo' can't be relied on..

OK, then we should use /bin/echo for avoiding this issue.

Thank you!

--
Masami Hiramatsu <mhiramat@kernel.org>