Re: [PATCH v3 1/3] perf evlist: Create a new function perf_evlist_forced_leader

[Arnaldo Carvalho de Melo]

Em Sat, May 19, 2018 at 12:00:32AM +0800, Jin Yao escreveu:
> For non-explicit group, perf report supports a option '--group'
> which can enable group output. We also need to support perf annotate
> with the same '--group'.
> 
> Create a new function perf_evlist_forced_leader which contains
> common code to force setting the group leader.
> 
> Signed-off-by: Jin Yao <yao.jin@xxxxxxxxxxxxxxx>
> ---
>  tools/perf/util/evlist.c | 15 +++++++++++++++
>  tools/perf/util/evlist.h |  3 +++
>  2 files changed, 18 insertions(+)
> 
> diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
> index a59281d..6983f6a 100644
> --- a/tools/perf/util/evlist.c
> +++ b/tools/perf/util/evlist.c
> @@ -1795,3 +1795,18 @@ bool perf_evlist__exclude_kernel(struct perf_evlist *evlist)
>  
>  	return true;
>  }
> +
> +/*
> + * Events in data file are not collect in groups, but we still want
> + * the group display. Set the artificial group and set the leader's
> + * forced_leader flag to notify the display code.
> + */
> +void perf_evlist_forced_leader(struct perf_evlist *evlist)

This should've been:

void perf_evlist__forced_leader(struct perf_evlist *evlist)

But then, by the verb conjugation, I thought that this would be a query,
i.e. "is this a forced leader?", but then, it returning void didn't
match that expectation, which leads me having to actually _read_ that
code to understand what is that this function does, which I would, but
just to check that it matches what it seems to be, now I'm trying to do
it to figure it out what is it that this thing does :-\


I see, its a 'd' to many, this should be:

void perf_evlist__force_leader(struct perf_evlist *evlist)

Please confirm that this is what you intend by posting a v4, so far,
just for this specific patch and any other in the series that uses this
function, ok?

- Arnaldo

> +{
> +	if (!evlist->nr_groups) {
> +		struct perf_evsel *leader = perf_evlist__first(evlist);
> +
> +		perf_evlist__set_leader(evlist);
> +		leader->forced_leader = true;
> +	}
> +}
> diff --git a/tools/perf/util/evlist.h b/tools/perf/util/evlist.h
> index 6c41b2f..d77d514 100644
> --- a/tools/perf/util/evlist.h
> +++ b/tools/perf/util/evlist.h
> @@ -309,4 +309,7 @@ struct perf_evsel *perf_evlist__event2evsel(struct perf_evlist *evlist,
>  					    union perf_event *event);
>  
>  bool perf_evlist__exclude_kernel(struct perf_evlist *evlist);
> +
> +void perf_evlist_forced_leader(struct perf_evlist *evlist);
> +
>  #endif /* __PERF_EVLIST_H */
> -- 
> 2.7.4