Re: perf tip: fails to convert comm

[Frederic Weisbecker <fweisbec@gmail.com>]

On Tue, Nov 12, 2013 at 09:58:29PM -0700, David Ahern wrote:
> Hi Namhyung and Frederic:
> 
> If you recall I mentioned noting a problem with the callchain series
> showing comm's. Well, it fails on acme's perf/core. git bisect
> points to:
> 
> $ git bisect bad
> 4dfced359fbc719a35527416f1b4b3999647f68b is the first bad commit
> commit 4dfced359fbc719a35527416f1b4b3999647f68b
> Author: Namhyung Kim <namhyung.kim@lge.com>
> Date:   Fri Sep 13 16:28:57 2013 +0900
> 
>     perf tools: Get current comm instead of last one
> 
>     At insert time, a hist entry should reference comm at the time
> otherwise
>     it'll get the last comm anyway.
> 
> 
> How to re-create:
> 
> Start point is tools/perf directory for 3.12 (Linus tree):
>   $ perf sched record -o /tmp/perf.data -g -- make -j 16
>   $ perf script -i /tmp/perf.data > /tmp/1
> 
> cd to Arnaldo's tree, make perf and use it to create /tmp/2:
>   $ perf script -i /tmp/perf.data > /tmp/1
>   $ diff -U3 /tmp/1 /tmp/2 | less
> 
> You'll see a number of comm's showing as :<pid> instead of make, etc.

I see. I can reproduce, I'll check and see what happens. It would be nice if
we could have an option to dump internal perf events like comm events as well
in the perf script stream.