tracing: Remove lookups from tracing_map hitcount

Lookups inflate the hitcount, making it essentially useless.  Only
inserts and updates should really affect the hitcount anyway, so
explicitly filter lookups out.

Link: http://lkml.kernel.org/r/c8d9dc39d269a8abf88bf4102d0dfc65deb0fc7f.1506105045.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

kernel/trace/tracing_map.c

@@ -428,7 +428,8 @@ __tracing_map_insert(struct tracing_map *map, void *key, bool lookup_only)
 
 		if (test_key && test_key == key_hash && entry->val &&
 		    keys_match(key, entry->val->key, map->key_size)) {
-			atomic64_inc(&map->hits);
+			if (!lookup_only)
+				atomic64_inc(&map->hits);
 			return entry->val;
 		}