On Wed, Jan 27, 2021 at 03:59:27PM +0100, Guoqing Jiang wrote:

+config BLK_ADDITIONAL_DISKSTAT
+	bool "Block layer additional diskstat"
+	default n

n is the default default.  But more importantly I don't think having
this as a compile time option makes much sense sense.  No one is going
to recompile their kernel to get a few stats or to avoid the overhead
of these stats.