Re: [PATCH] perf config: Refine error message to eliminate confusion

[Arnaldo Carvalho de Melo]

Em Fri, Sep 24, 2021 at 08:08:07AM -0700, Ian Rogers escreveu:
> On Fri, Sep 24, 2021 at 4:58 AM Like Xu <like.xu.linux@xxxxxxxxx> wrote:
> >
> > From: Like Xu <likexu@xxxxxxxxxxx>
> >
> > If there is no configuration file at first, the user can
> > write any pair of "key.subkey=value" to the newly created
> > configuration file, while value validation against a valid
> > configurable key is *deferred* until the next execution or
> > the implied execution of "perf config ... ".
> >
> > For example:
> >
> >  $ rm ~/.perfconfig
> >  $ perf config call-graph.dump-size=65529
> >  $ cat ~/.perfconfig
> >  # this file is auto-generated.
> >  [call-graph]
> >         dump-size = 65529
> >  $ perf config call-graph.dump-size=2048
> >  callchain: Incorrect stack dump size (max 65528): 65529
> >  Error: wrong config key-value pair call-graph.dump-size=65529
> >
> > The user might expect that the second value 2048 is valid
> > and can be updated to the configuration file, but the error
> > message is very confusing because the first value 65529 is
> > not reported as an error during the last configuration.
> >
> > It is recommended not to change the current behavior of
> > delayed validation (as more effort is needed), but to refine
> > the original error message to *clearly indicate* that the
> > cause of the error is the configuration file.
> >
> > Signed-off-by: Like Xu <likexu@xxxxxxxxxxx>
> 
> Acked-by: Ian Rogers <irogers@xxxxxxxxxx>

Thanks, applied.

- Arnaldo

 
> Thanks,
> Ian
> 
> > ---
> >  tools/perf/util/config.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/tools/perf/util/config.c b/tools/perf/util/config.c
> > index 4fb5e90d7a57..60ce5908c664 100644
> > --- a/tools/perf/util/config.c
> > +++ b/tools/perf/util/config.c
> > @@ -801,7 +801,7 @@ int perf_config_set(struct perf_config_set *set,
> >                                   section->name, item->name);
> >                         ret = fn(key, value, data);
> >                         if (ret < 0) {
> > -                               pr_err("Error: wrong config key-value pair %s=%s\n",
> > +                               pr_err("Error in the given config file: wrong config key-value pair %s=%s\n",
> >                                        key, value);
> >                                 /*
> >                                  * Can't be just a 'break', as perf_config_set__for_each_entry()
> > --
> > 2.32.0
> >

-- 

- Arnaldo