Re: [PATCH v2 1/3] perf diff: Support --time filter option

[Jin, Yao]

On 2/27/2019 5:28 PM, Jiri Olsa wrote:
> On Tue, Feb 26, 2019 at 08:11:07PM +0800, Jin Yao wrote:
>
> SNIP
>
> > +		.ordered_events = true,
> > +		.ordering_requires_timestamps = true,
> > +	},
> >   };
> >   
> >   static struct perf_evsel *evsel_match(struct perf_evsel *evsel,
> > @@ -771,19 +788,136 @@ static void data__free(struct data__file *d)
> >   	}
> >   }
> >   
> > +static int parse_time_range(struct data__file *d,
> > +			    struct perf_time_interval *ptime_range,
> > +			    const char *time_str)
> > +{
> > +	if (perf_time__parse_str(ptime_range,
> > +				 time_str) != 0) {
> > +		if (d->session->evlist->first_sample_time == 0 &&
> > +		    d->session->evlist->last_sample_time == 0) {
> > +			pr_err("HINT: no first/last sample time found in perf data.\n"
> > +			       "Please use latest perf binary to execute 'perf record'\n"
> > +			       "(if '--buildid-all' is enabled, please set '--timestamp-boundary').\n");
> > +			return -EINVAL;
> > +		}
> > +
> > +		pdiff.range_num = perf_time__percent_parse_str(
> > +				ptime_range, pdiff.range_size, time_str,
> > +				d->session->evlist->first_sample_time,
> > +				d->session->evlist->last_sample_time);
> > +
> > +		if (pdiff.range_num < 0) {
> > +			pr_err("Invalid time string\n");
> > +			return -EINVAL;
> > +		}
> > +	} else {
> > +		pdiff.range_num = 1;
>
> I dont understand why we set range_num to 1 if there's
> not time option set.. it should be 0 and we should take
> no action in diff__process_sample_event, right?
>
> then I checked the report code and we do the same,
> could we fix that? I'm assuming we don't need any
> time check if the time option is not set.. please
> correct me if I miss something
>
> jirka

We support multiple complicated time strings. :(

In parse_time_range(), perf_time__parse_str() returns 0 if the time 
string is a simple start/stop format. So next, we set the range_num to 
1. If the time string contains multiple time percent ranges (e.g. 
"10%/1,10%/2,..."), perf_time__parse_str() will return with error (<0), 
then we will continue checking with perf_time__percent_parse_str().

So when range_num is set to 1, it just means it's the simple time string.

Thanks
Jin Yao