perf hist: Calculate max_sym name len and nr_entries

Better done when we are adding entries, be it initially of when we're
re-sorting the histograms.

Cc: Frédéric Weisbecker <[e-mail]>
Cc: Mike Galbraith <[e-mail]>
Cc: Paul Mackerras <[e-mail]>
Cc: Peter Zijlstra <[e-mail]>
Cc: Tom Zanussi <[e-mail]>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <[e-mail]>

tools/perf/builtin-report.c

···
 	next = rb_first(&session->hists_tree);
 	while (next) {
 		struct hists *hists;
-		u64 nr_hists;
 
 		hists = rb_entry(next, struct hists, rb_node);
 		hists__collapse_resort(hists);
-		nr_hists = hists__output_resort(hists);
+		hists__output_resort(hists);
 		if (use_browser)
-			perf_session__browse_hists(&hists->entries, nr_hists,
+			perf_session__browse_hists(&hists->entries,
+						   hists->nr_entries,
 						   hists->stats.total, help,
 						   input_name);
 		else {

tools/perf/util/hist.c

···
 	return self;
 }
 
+static void hists__inc_nr_entries(struct hists *self, struct hist_entry *entry)
+{
+	if (entry->ms.sym && self->max_sym_namelen < entry->ms.sym->namelen)
+		self->max_sym_namelen = entry->ms.sym->namelen;
+	++self->nr_entries;
+}
+
 struct hist_entry *__hists__add_entry(struct hists *self,
 				      struct addr_location *al,
 				      struct symbol *sym_parent, u64 count)
···
 		return NULL;
 	rb_link_node(&he->rb_node, parent, p);
 	rb_insert_color(&he->rb_node, &self->entries);
+	hists__inc_nr_entries(self, he);
 out:
 	hist_entry__add_cpumode_count(he, al->cpumode, count);
 	return he;
···
  * collapse the histogram
  */
 
-static void collapse__insert_entry(struct rb_root *root, struct hist_entry *he)
+static bool collapse__insert_entry(struct rb_root *root, struct hist_entry *he)
 {
 	struct rb_node **p = &root->rb_node;
 	struct rb_node *parent = NULL;
···
 		if (!cmp) {
 			iter->count += he->count;
 			hist_entry__free(he);
-			return;
+			return false;
 		}
 
 		if (cmp < 0)
···
 
 	rb_link_node(&he->rb_node, parent, p);
 	rb_insert_color(&he->rb_node, root);
+	return true;
 }
 
 void hists__collapse_resort(struct hists *self)
···
 
 	tmp = RB_ROOT;
 	next = rb_first(&self->entries);
+	self->nr_entries = 0;
+	self->max_sym_namelen = 0;
 
 	while (next) {
 		n = rb_entry(next, struct hist_entry, rb_node);
 		next = rb_next(&n->rb_node);
 
 		rb_erase(&n->rb_node, &self->entries);
-		collapse__insert_entry(&tmp, n);
+		if (collapse__insert_entry(&tmp, n))
+			hists__inc_nr_entries(self, n);
 	}
 
 	self->entries = tmp;
···
 	rb_insert_color(&he->rb_node, entries);
 }
 
-u64 hists__output_resort(struct hists *self)
+void hists__output_resort(struct hists *self)
 {
 	struct rb_root tmp;
 	struct rb_node *next;
 	struct hist_entry *n;
 	u64 min_callchain_hits;
-	u64 nr_hists = 0;
 
 	min_callchain_hits = self->stats.total * (callchain_param.min_percent / 100);
 
 	tmp = RB_ROOT;
 	next = rb_first(&self->entries);
+
+	self->nr_entries = 0;
+	self->max_sym_namelen = 0;
 
 	while (next) {
 		n = rb_entry(next, struct hist_entry, rb_node);
···
 
 		rb_erase(&n->rb_node, &self->entries);
 		__hists__insert_output_entry(&tmp, n, min_callchain_hits);
-		++nr_hists;
+		hists__inc_nr_entries(self, n);
 	}
 
 	self->entries = tmp;
-	return nr_hists;
 }
 
 static size_t callchain__fprintf_left_margin(FILE *fp, int left_margin)

tools/perf/util/hist.h

···
 struct hists {
 	struct rb_node		rb_node;
 	struct rb_root		entries;
+	u64			nr_entries;
 	struct events_stats	stats;
 	u64			config;
 	u64			event_stream;
 	u32			type;
+	u32			max_sym_namelen;
 };
 
 struct hist_entry *__hists__add_entry(struct hists *self,
···
 			 long displacement, bool color, u64 total);
 void hist_entry__free(struct hist_entry *);
 
-u64 hists__output_resort(struct hists *self);
+void hists__output_resort(struct hists *self);
 void hists__collapse_resort(struct hists *self);
 size_t hists__fprintf(struct hists *self, struct hists *pair,
 		      bool show_displacement, FILE *fp);

tools/perf/util/symbol.c

···
 	if (symbol_conf.priv_size)
 		self = ((void *)self) + symbol_conf.priv_size;
 
-	self->start = start;
-	self->end   = len ? start + len - 1 : start;
+	self->start   = start;
+	self->end     = len ? start + len - 1 : start;
+	self->namelen = namelen - 1;
 
 	pr_debug4("%s: %s %#Lx-%#Lx\n", __func__, name, start, self->end);
 

tools/perf/util/symbol.h

···
 	struct rb_node	rb_node;
 	u64		start;
 	u64		end;
+	u16		namelen;
 	char		name[0];
 };