Re: [PATCH 2/7] perf hist: Introduce hists__match_hierarchy()

[Arnaldo Carvalho de Melo <acme@kernel.org>]

Em Mon, Sep 12, 2016 at 03:19:53PM +0900, Namhyung Kim escreveu:
> The hists__match_hierarchy() is to find matching hist entries in a
> group.  It needs to search all matching children in the hierarchy.

Can you please enrich this changeset log? Define "matching", an example
of how the output of a hierarchy + group would help people trying to
understand the changes you're making, for instance.

- Arnaldo
 
> Signed-off-by: Namhyung Kim <namhyung@kernel.org>
> ---
>  tools/perf/util/hist.c | 51 ++++++++++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 51 insertions(+)
> 
> diff --git a/tools/perf/util/hist.c b/tools/perf/util/hist.c
> index de15dbcdcecf..be3f5ce31303 100644
> --- a/tools/perf/util/hist.c
> +++ b/tools/perf/util/hist.c
> @@ -2174,6 +2174,51 @@ static struct hist_entry *hists__find_entry(struct hists *hists,
>  	return NULL;
>  }
>  
> +static struct hist_entry *hists__find_hierarchy_entry(struct rb_root *root,
> +						      struct hist_entry *he)
> +{
> +	struct rb_node *n = root->rb_node;
> +
> +	while (n) {
> +		struct hist_entry *iter;
> +		struct perf_hpp_fmt *fmt;
> +		int64_t cmp = 0;
> +
> +		iter = rb_entry(n, struct hist_entry, rb_node_in);
> +		perf_hpp_list__for_each_sort_list(he->hpp_list, fmt) {
> +			cmp = fmt->collapse(fmt, iter, he);
> +			if (cmp)
> +				break;
> +		}
> +
> +		if (cmp < 0)
> +			n = n->rb_left;
> +		else if (cmp > 0)
> +			n = n->rb_right;
> +		else
> +			return iter;
> +	}
> +
> +	return NULL;
> +}
> +
> +static void hists__match_hierarchy(struct rb_root *leader_root,
> +				   struct rb_root *other_root)
> +{
> +	struct rb_node *nd;
> +	struct hist_entry *pos, *pair;
> +
> +	for (nd = rb_first(leader_root); nd; nd = rb_next(nd)) {
> +		pos  = rb_entry(nd, struct hist_entry, rb_node_in);
> +		pair = hists__find_hierarchy_entry(other_root, pos);
> +
> +		if (pair) {
> +			hist_entry__add_pair(pair, pos);
> +			hists__match_hierarchy(&pos->hroot_in, &pair->hroot_in);
> +		}
> +	}
> +}
> +
>  /*
>   * Look for pairs to link to the leader buckets (hist_entries):
>   */
> @@ -2183,6 +2228,12 @@ void hists__match(struct hists *leader, struct hists *other)
>  	struct rb_node *nd;
>  	struct hist_entry *pos, *pair;
>  
> +	if (symbol_conf.report_hierarchy) {
> +		/* hierarchy report always collapses entries */
> +		return hists__match_hierarchy(&leader->entries_collapsed,
> +					      &other->entries_collapsed);
> +	}
> +
>  	if (hists__has(leader, need_collapse))
>  		root = &leader->entries_collapsed;
>  	else
> -- 
> 2.9.3