perf hist: Add perf_hpp_fmt->init() callback

In __hists__insert_output_entry(), it calls fmt->sort() for dynamic
entries with NULL to update column width for tracepoint fields.
But it's a hacky abuse of the sort callback, better to have a proper
callback for that. I'll add more use cases later.

Signed-off-by: Namhyung Kim <[e-mail]>
Acked-by: Ian Rogers <[e-mail]>
Cc: Adrian Hunter <[e-mail]>
Cc: Andi Kleen <[e-mail]>
Cc: Ingo Molnar <[e-mail]>
Cc: Jiri Olsa <[e-mail]>
Cc: Leo Yan <[e-mail]>
Cc: Milian Wolff <[e-mail]>
Cc: Peter Zijlstra <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Arnaldo Carvalho de Melo <[e-mail]>

tools/perf/util/hist.c

···
 
 	/* update column width of dynamic entry */
 	perf_hpp_list__for_each_sort_list(he->hpp_list, fmt) {
-		if (perf_hpp__is_dynamic_entry(fmt))
-			fmt->sort(fmt, he, NULL);
+		if (fmt->init)
+			fmt->init(fmt, he);
 	}
 }
 
···
 	rb_link_node(&he->rb_node, parent, p);
 	rb_insert_color_cached(&he->rb_node, entries, leftmost);
 
+	/* update column width of dynamic entries */
 	perf_hpp_list__for_each_sort_list(&perf_hpp_list, fmt) {
-		if (perf_hpp__is_dynamic_entry(fmt) &&
-		    perf_hpp__defined_dynamic_entry(fmt, he->hists))
-			fmt->sort(fmt, he, NULL);  /* update column width */
+		if (fmt->init)
+			fmt->init(fmt, he);
 	}
 }
 

tools/perf/util/hist.h

···
 		      struct hists *hists, int line, int *span);
 	int (*width)(struct perf_hpp_fmt *fmt, struct perf_hpp *hpp,
 		     struct hists *hists);
+	void (*init)(struct perf_hpp_fmt *fmt, struct hist_entry *he);
 	int (*color)(struct perf_hpp_fmt *fmt, struct perf_hpp *hpp,
 		     struct hist_entry *he);
 	int (*entry)(struct perf_hpp_fmt *fmt, struct perf_hpp *hpp,

tools/perf/util/sort.c

···
 	free(hse);
 }
 
+static void hse_init(struct perf_hpp_fmt *fmt, struct hist_entry *he)
+{
+	struct hpp_sort_entry *hse;
+
+	if (!perf_hpp__is_sort_entry(fmt))
+		return;
+
+	hse = container_of(fmt, struct hpp_sort_entry, hpp);
+
+	if (hse->se->se_init)
+		hse->se->se_init(he);
+}
+
 static struct hpp_sort_entry *
 __sort_dimension__alloc_hpp(struct sort_dimension *sd, int level)
 {
···
 	hse->hpp.sort = __sort__hpp_sort;
 	hse->hpp.equal = __sort__hpp_equal;
 	hse->hpp.free = hse_free;
+	hse->hpp.init = hse_init;
 
 	INIT_LIST_HEAD(&hse->hpp.list);
 	INIT_LIST_HEAD(&hse->hpp.sort_list);
···
 
 	hde = container_of(fmt, struct hpp_dynamic_entry, hpp);
 
-	if (b == NULL) {
-		update_dynamic_len(hde, a);
-		return 0;
-	}
-
 	field = hde->field;
 	if (field->flags & TEP_FIELD_IS_DYNAMIC) {
 		unsigned long long dyn;
···
 	free(hde);
 }
 
+static void __sort__hde_init(struct perf_hpp_fmt *fmt, struct hist_entry *he)
+{
+	struct hpp_dynamic_entry *hde;
+
+	if (!perf_hpp__is_dynamic_entry(fmt))
+		return;
+
+	hde = container_of(fmt, struct hpp_dynamic_entry, hpp);
+	update_dynamic_len(hde, he);
+}
+
 static struct hpp_dynamic_entry *
 __alloc_dynamic_entry(struct evsel *evsel, struct tep_format_field *field,
 		      int level)
···
 	hde->hpp.entry  = __sort__hde_entry;
 	hde->hpp.color  = NULL;
 
+	hde->hpp.init = __sort__hde_init;
 	hde->hpp.cmp = __sort__hde_cmp;
 	hde->hpp.collapse = __sort__hde_cmp;
 	hde->hpp.sort = __sort__hde_cmp;

tools/perf/util/sort.h

···
 	int	(*se_snprintf)(struct hist_entry *he, char *bf, size_t size,
 			       unsigned int width);
 	int	(*se_filter)(struct hist_entry *he, int type, const void *arg);
+	void	(*se_init)(struct hist_entry *he);
 	u8	se_width_idx;
 };