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

[Taeung Song <taeung.dev@gmail.com>]

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@kernel.org>
>> Cc: Namhyung Kim <namhyung@kernel.org>
>> Signed-off-by: Taeung Song <treeze.taeung@gmail.com>
>> ---
>>  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