perf_counter tools: Add more warnings and fix/annotate them

Enable -Wextra. This found a few real bugs plus a number
of signed/unsigned type mismatches/uncleanlinesses. It
also required a few annotations

All things considered it was still worth it so lets try with
this enabled for now.

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/tools/perf/util/color.c b/tools/perf/util/color.c
index 9a8c20c..26f8231 100644
--- a/tools/perf/util/color.c
+++ b/tools/perf/util/color.c
@@ -11,7 +11,8 @@
 	};
 	char *end;
 	int i;
-	for (i = 0; i < ARRAY_SIZE(color_names); i++) {
+
+	for (i = 0; i < (int)ARRAY_SIZE(color_names); i++) {
 		const char *str = color_names[i];
 		if (!strncasecmp(name, str, len) && !str[len])
 			return i - 1;
@@ -28,7 +29,8 @@
 	static const char * const attr_names[] = {
 		"bold", "dim", "ul", "blink", "reverse"
 	};
-	int i;
+	unsigned int i;
+
 	for (i = 0; i < ARRAY_SIZE(attr_names); i++) {
 		const char *str = attr_names[i];
 		if (!strncasecmp(name, str, len) && !str[len])
@@ -222,10 +224,12 @@
 {
 	if (!*color)
 		return fwrite(buf, count, 1, fp) != 1;
+
 	while (count) {
 		char *p = memchr(buf, '\n', count);
+
 		if (p != buf && (fputs(color, fp) < 0 ||
-				fwrite(buf, p ? p - buf : count, 1, fp) != 1 ||
+				fwrite(buf, p ? (size_t)(p - buf) : count, 1, fp) != 1 ||
 				fputs(PERF_COLOR_RESET, fp) < 0))
 			return -1;
 		if (!p)