block: Do not collect I/O statistics

This adds a great deal of latency to block requests due to disabling
preemption temporarily during statistics collection.

Signed-off-by: Tyler Nijmeh <tylernij@gmail.com>
Signed-off-by: sohamxda7 <sensoham135@gmail.com>

Author: tytydraco

include/linux/blkdev.h

@@ -501,13 +501,11 @@ struct request_queue {
 #define QUEUE_FLAG_FAST        23	/* fast block device (e.g. ram based) */
 #define QUEUE_FLAG_INLINECRYPT 24	/* inline encryption support */
 
-#define QUEUE_FLAG_DEFAULT	((1 << QUEUE_FLAG_IO_STAT) |		\
-				 (1 << QUEUE_FLAG_STACKABLE)	|	\
+#define QUEUE_FLAG_DEFAULT	((1 << QUEUE_FLAG_STACKABLE)	|	\
 				 (1 << QUEUE_FLAG_SAME_COMP)	|	\
 				 (1 << QUEUE_FLAG_ADD_RANDOM))
 
-#define QUEUE_FLAG_MQ_DEFAULT	((1 << QUEUE_FLAG_IO_STAT) |		\
-				 (1 << QUEUE_FLAG_STACKABLE)	|	\
+#define QUEUE_FLAG_MQ_DEFAULT	((1 << QUEUE_FLAG_STACKABLE)	|	\
 				 (1 << QUEUE_FLAG_SAME_COMP))
 
 static inline void queue_lockdep_assert_held(struct request_queue *q)