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

Jin, Yao
2019-02-27T14:24:35Z

On 2/27/2019 9:10 PM, Jiri Olsa wrote:
> On Wed, Feb 27, 2019 at 08:51:44PM +0800, Jin, Yao wrote:
>>
>>
>> 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.
>
> why do we need to have time range set if there's no --time
> option set by user?
>
> jirka
>

Yes, that could be refined if no --time option set by user. I think I
can add a new patch to fix these for perf report/script.

Thanks
Jin Yao