diff --git a/tools/perf/util/help.c b/tools/perf/util/help.c
index 17a00e0..fbb0097 100644
--- a/tools/perf/util/help.c
+++ b/tools/perf/util/help.c
@@ -26,7 +26,7 @@
 	return 80;
 }
 
-void add_cmdname(struct cmdnames *cmds, const char *name, int len)
+void add_cmdname(struct cmdnames *cmds, const char *name, size_t len)
 {
 	struct cmdname *ent = malloc(sizeof(*ent) + len + 1);
 
@@ -40,7 +40,8 @@
 
 static void clean_cmdnames(struct cmdnames *cmds)
 {
-	int i;
+	unsigned int i;
+
 	for (i = 0; i < cmds->cnt; ++i)
 		free(cmds->names[i]);
 	free(cmds->names);
@@ -57,7 +58,7 @@
 
 static void uniq(struct cmdnames *cmds)
 {
-	int i, j;
+	unsigned int i, j;
 
 	if (!cmds->cnt)
 		return;
@@ -71,7 +72,7 @@
 
 void exclude_cmds(struct cmdnames *cmds, struct cmdnames *excludes)
 {
-	int ci, cj, ei;
+	size_t ci, cj, ei;
 	int cmp;
 
 	ci = cj = ei = 0;
@@ -106,8 +107,9 @@
 		printf("  ");
 
 		for (j = 0; j < cols; j++) {
-			int n = j * rows + i;
-			int size = space;
+			unsigned int n = j * rows + i;
+			unsigned int size = space;
+
 			if (n >= cmds->cnt)
 				break;
 			if (j == cols-1 || n + rows >= cmds->cnt)
@@ -208,7 +210,7 @@
 void list_commands(const char *title, struct cmdnames *main_cmds,
 		   struct cmdnames *other_cmds)
 {
-	int i, longest = 0;
+	unsigned int i, longest = 0;
 
 	for (i = 0; i < main_cmds->cnt; i++)
 		if (longest < main_cmds->names[i]->len)
@@ -239,7 +241,8 @@
 
 int is_in_cmdlist(struct cmdnames *c, const char *s)
 {
-	int i;
+	unsigned int i;
+
 	for (i = 0; i < c->cnt; i++)
 		if (!strcmp(s, c->names[i]->name))
 			return 1;
@@ -271,7 +274,8 @@
 
 static void add_cmd_list(struct cmdnames *cmds, struct cmdnames *old)
 {
-	int i;
+	unsigned int i;
+
 	ALLOC_GROW(cmds->names, cmds->cnt + old->cnt, cmds->alloc);
 
 	for (i = 0; i < old->cnt; i++)
@@ -283,7 +287,7 @@
 
 const char *help_unknown_cmd(const char *cmd)
 {
-	int i, n = 0, best_similarity = 0;
+	unsigned int i, n = 0, best_similarity = 0;
 	struct cmdnames main_cmds, other_cmds;
 
 	memset(&main_cmds, 0, sizeof(main_cmds));
@@ -345,7 +349,7 @@
 	exit(1);
 }
 
-int cmd_version(int argc, const char **argv, const char *prefix)
+int cmd_version(int argc __used, const char **argv __used, const char *prefix __used)
 {
 	printf("perf version %s\n", perf_version_string);
 	return 0;