perf tools: Add overhead/overhead_children keys defaults via string

We currently set 'overhead' and 'overhead_children' as default sort keys
within perf_hpp__init function by directly adding into the sort list.

This patch adds 'overhead' and 'overhead_children' in text form into
sort_keys and let them be added by standard sort dimension interface.

We need to eliminate dirrect sort_list additions to be able to add
support for hists specific sort keys.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Noel Grandin <noelgrandin@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1452158050-28061-12-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/ui/hist.c

@@ -443,7 +443,6 @@ LIST_HEAD(perf_hpp__sort_list);
 
 void perf_hpp__init(void)
 {
-	struct list_head *list;
 	int i;
 
 	for (i = 0; i < PERF_HPP__MAX_INDEX; i++) {
@@ -484,17 +483,6 @@ void perf_hpp__init(void)
 
 	if (symbol_conf.show_total_period)
 		hpp_dimension__add_output(PERF_HPP__PERIOD);
-
-	/* prepend overhead field for backward compatiblity.  */
-	list = &perf_hpp__format[PERF_HPP__OVERHEAD].sort_list;
-	if (list_empty(list))
-		list_add(list, &perf_hpp__sort_list);
-
-	if (symbol_conf.cumulate_callchain) {
-		list = &perf_hpp__format[PERF_HPP__OVERHEAD_ACC].sort_list;
-		if (list_empty(list))
-			list_add(list, &perf_hpp__sort_list);
-	}
 }
 
 void perf_hpp__column_register(struct perf_hpp_fmt *format)

tools/perf/util/sort.c

@@ -2252,6 +2252,34 @@ static int setup_sort_order(struct perf_evlist *evlist)
 	return 0;
 }
 
+/*
+ * Adds 'pre,' prefix into 'str' is 'pre' is
+ * not already part of 'str'.
+ */
+static char *prefix_if_not_in(const char *pre, char *str)
+{
+	char *n;
+
+	if (!str || strstr(str, pre))
+		return str;
+
+	if (asprintf(&n, "%s,%s", pre, str) < 0)
+		return NULL;
+
+	free(str);
+	return n;
+}
+
+static char *setup_overhead(char *keys)
+{
+	keys = prefix_if_not_in("overhead", keys);
+
+	if (symbol_conf.cumulate_callchain)
+		keys = prefix_if_not_in("overhead_children", keys);
+
+	return keys;
+}
+
 static int __setup_sorting(struct perf_evlist *evlist)
 {
 	char *tmp, *tok, *str;
@@ -2281,6 +2309,17 @@ static int __setup_sorting(struct perf_evlist *evlist)
 		return -ENOMEM;
 	}
 
+	/*
+	 * Prepend overhead fields for backward compatibility.
+	 */
+	if (!is_strict_order(field_order)) {
+		str = setup_overhead(str);
+		if (str == NULL) {
+			error("Not enough memory to setup overhead keys");
+			return -ENOMEM;
+		}
+	}
+
 	for (tok = strtok_r(str, ", ", &tmp);
 			tok; tok = strtok_r(NULL, ", ", &tmp)) {
 		ret = sort_dimension__add(tok, evlist);