Re: [PATCHv2 0/3] perf tools: Add support for user defined metric

[Jiri Olsa <jolsa@redhat.com>]

On Thu, Apr 30, 2020 at 04:54:41PM +0530, kajoljain wrote:
> 
> 
> On 4/21/20 11:43 PM, Jiri Olsa wrote:
> > hi,
> > Joe asked for possibility to add user defined metrics. Given that
> > we already have metrics support, I added --metrics-file option that
> > allows to specify custom metrics.
> > 
> >   $ cat metrics
> >   # IPC
> >   mine1 = instructions / cycles;
> >   /* DECODED_ICACHE_UOPS% */
> >   mine2 = 100 * (idq.dsb_uops / \ (idq.ms_uops + idq.mite_uops + idq.dsb_uops + lsd.uops));
> > 
> >   $ sudo perf stat --metrics-file ./metrics -M mine1,mine2 --metric-only -a -I 1000
> >   #           time       insn per cycle                mine1                mine2
> >        1.000536263                0.71                   0.7                 41.4
> >        2.002069025                0.31                   0.3                 14.1
> >        3.003427684                0.27                   0.3                 14.8
> >        4.004807132                0.25                   0.2                 12.1
> >   ...
> > 
> > v2 changes:
> >   - add new --metrics-file option
> >   - rebased on current perf/core expression bison/flex enhancements
> > 
> > Also available in:
> >   git://git.kernel.org/pub/scm/linux/kernel/git/jolsa/perf.git
> >   perf/metric
> > 
> > thanks,
> > jirka
> > 
> > 
> > ---
> > Jiri Olsa (3):
> >       perf expr: Add parsing support for multiple expressions
> >       perf expr: Allow comments in custom metric file
> >       perf stat: Add --metrics-file option
> 
> Hi Jiri,
>      I try to look into these patches. As far as I understand we are using
> syntax "Name: Expression" for user defined events. It will be great if we mention
> this format somewhere for users.

right, Andi also asked for that, I'll describe it in a man page

> 
> Otherwise it works fine for me. Try by testing it for different metric expressions.

thanks for testing

> But still curious about reason for adding this support. Isn't json file is there for same purpose?

we've been asked by Joe about the possibility to specify metric by user
through the command line..  with json you have all them compiled in and 
you can't change them or specify your own without recompiling perf

jirka

> 
> Thanks,
> Kajol Jain
> > 
> >  tools/perf/Documentation/perf-stat.txt |  3 +++
> >  tools/perf/builtin-stat.c              |  7 +++++--
> >  tools/perf/tests/expr.c                | 13 +++++++++++++
> >  tools/perf/util/expr.c                 |  6 ++++++
> >  tools/perf/util/expr.h                 | 19 +++++++++++++++++--
> >  tools/perf/util/expr.l                 | 24 ++++++++++++++++++++++++
> >  tools/perf/util/expr.y                 | 13 ++++++++++++-
> >  tools/perf/util/metricgroup.c          | 66 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-------
> >  tools/perf/util/metricgroup.h          |  3 ++-
> >  tools/perf/util/stat.h                 |  1 +
> >  10 files changed, 142 insertions(+), 13 deletions(-)
> > 
>