perf callchains: Use zalloc to allocate objects

Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/callchain.c

@@ -167,7 +167,7 @@ create_child(struct callchain_node *parent, bool inherit_children)
 {
 	struct callchain_node *new;
 
-	new = malloc(sizeof(*new));
+	new = zalloc(sizeof(*new));
 	if (!new) {
 		perror("not enough memory to create child for code path tree");
 		return NULL;
@@ -213,7 +213,7 @@ fill_node(struct callchain_node *node, struct resolved_chain *chain, int start)
 	for (i = start; i < chain->nr; i++) {
 		struct callchain_list *call;
 
-		call = malloc(sizeof(*call));
+		call = zalloc(sizeof(*call));
 		if (!call) {
 			perror("not enough memory for the code path tree");
 			return;
@@ -386,7 +386,7 @@ int append_chain(struct callchain_node *root, struct ip_callchain *chain,
 	if (!chain->nr)
 		return 0;
 
-	filtered = malloc(sizeof(*filtered) +
+	filtered = zalloc(sizeof(*filtered) +
 			  chain->nr * sizeof(struct resolved_ip));
 	if (!filtered)
 		return -ENOMEM;