[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20131011073448.GA11064@krava.redhat.com>
Date: Fri, 11 Oct 2013 09:34:48 +0200
From: Jiri Olsa <jolsa@...hat.com>
To: Ingo Molnar <mingo@...nel.org>
Cc: Namhyung Kim <namhyung@...nel.org>,
Arnaldo Carvalho de Melo <acme@...stprotocols.net>,
Peter Zijlstra <a.p.zijlstra@...llo.nl>,
Paul Mackerras <paulus@...ba.org>,
Namhyung Kim <namhyung.kim@....com>,
LKML <linux-kernel@...r.kernel.org>,
Linus Torvalds <torvalds@...ux-foundation.org>,
Frederic Weisbecker <fweisbec@...il.com>
Subject: Re: [PATCHSET 0/8] perf tools: Fix scalability problem on callchain
merging (v5)
On Fri, Oct 11, 2013 at 07:58:29AM +0200, Ingo Molnar wrote:
>
> * Namhyung Kim <namhyung@...nel.org> wrote:
>
> > Hello,
> >
> > This is a new version of callchain improvement patchset. Basically
> > it's almost same as v4 but rebased on current acme/perf/core and some
> > functions are renamed as Frederic requested.
> >
> > Now I'm hunting down a bug in 'perf report -s sym' which was found
> > during the test, but I think it's not related to this change as it can
> > be reproduced in earlier versions too.
> >
> > I put this series on 'perf/callchain-v5' branch in my tree
> >
> > git://git.kernel.org/pub/scm/linux/kernel/git/namhyung/linux-perf.git
> >
> > Any comments are welcome, thanks.
>
> One thing I noticed about call-graph profiling:
>
> comet:~/tip/tools/perf> ./perf record -g ~/hackbench 10
> callchain: Unknown -g option value: /home/mingo/hackbench
>
> I think a naked -g used to work just fine in the past. Even if such an
> error is displayed the output is very unhelpful, it does does a full
> perf-record options dump (unnecessary), the bit that is helpful is hidden
> amongst many other options:
>
> -g, --call-graph <mode[,dump_size]>
> do call-graph (stack chain/backtrace) recording: [fp] dwarf
>
> and it took me two reads to see that I should specify 'fp'. The '[fp]'
> indicates that fp is the default - but that does not appear to be working.
'-g' takes optional parameter, so having it in front of
non option string is causing the error, you could use:
./perf record -g -- ~/hackbench 10
maybe we could display just only help string of the option
we failed to process in this case
jirka
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists