Re: [PATCH v2 2/4] perf config: Finally write changed configs on config file at a time

[Taeung Song]

On 05/09/2017 01:37 AM, Arnaldo Carvalho de Melo wrote:
> Em Mon, May 08, 2017 at 08:07:40PM +0900, Taeung Song escreveu:
> > Currently set_config() can be repeatedly called for each
> > input config on the below case:
> >
> >   $ perf config kmem.default=slab report.children=false ...
> >
> > But it's a waste, so finally write changed configs at a time.
> >
> > Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
> > Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
> > Signed-off-by: Taeung Song <treeze.taeung@xxxxxxxxx>
> > ---
> >  tools/perf/builtin-config.c | 15 ++++++++++-----
> >  1 file changed, 10 insertions(+), 5 deletions(-)
> >
> > diff --git a/tools/perf/builtin-config.c b/tools/perf/builtin-config.c
> > index 7545966..0d38599 100644
> > --- a/tools/perf/builtin-config.c
> > +++ b/tools/perf/builtin-config.c
> > @@ -33,8 +33,7 @@ static struct option config_options[] = {
> >  	OPT_END()
> >  };
> >
> > -static int set_config(struct perf_config_set *set, const char *file_name,
> > -		      const char *var, const char *value)
> > +static int set_config(struct perf_config_set *set, const char *file_name)
> >  {
> >  	struct perf_config_section *section = NULL;
> >  	struct perf_config_item *item = NULL;
> > @@ -48,7 +47,6 @@ static int set_config(struct perf_config_set *set, const char *file_name,
> >  	if (!fp)
> >  		return -1;
> >
> > -	perf_config_set__collect(set, file_name, var, value);
> >  	fprintf(fp, "%s\n", first_line);
> >
> >  	/* overwrite configvariables */
> > @@ -160,6 +158,7 @@ int cmd_config(int argc, const char **argv)
> >  	struct perf_config_set *set;
> >  	char *user_config = mkpath("%s/.perfconfig", getenv("HOME"));
> >  	const char *config_filename;
> > +	bool changed = false;
> >
> >  	argc = parse_options(argc, argv, config_options, config_usage,
> >  			     PARSE_OPT_STOP_AT_NON_OPTION);
> > @@ -227,10 +226,16 @@ int cmd_config(int argc, const char **argv)
> >
> >  			if (value == NULL)
> >  				ret = show_spec_config(set, var);
> > -			else
> > -				ret = set_config(set, config_filename, var, value);
> > +			else {
> > +				perf_config_set__collect(set, config_filename,
> > +							 var, value);
> > +				changed = true;
> > +			}
> >  			free(arg);
> >  		}
> > +
> > +		if (changed)
> > +			ret = set_config(set, config_filename);
>
> Ok, this improves the situation, even fixing what seems like a bug, i.e.
> that ret variable set in the if (value == NULL) case is not being
> checked, the look just goes on to completion and whatever is the last
> value left in 'ret' is what will be returned by cmd_config()...
>
> I think we should fix that bug first, making it exit the loop and
> perhaps show some error message, then do this 'call set_config()' only
> at the end', no?

I understood !
will fix the bug you mentioned first,
before this patch.

> I applied the first patch, the one just renesting things.
>
> - Arnaldo

Thank you !,
Taeung

> >  	}
> >
> >  	perf_config_set__delete(set);
> > --
> > 2.7.4