freebsd-nq/sys/cddl
Mark Johnston efe8b26b82 Modify lockstat_nsecs() to just return unless lockstat probes are actually
enabled. The cost of a timecounter read can be quite significant, and the
problem became more apparent after r284297, since that change resulted in
a call to lockstat_nsecs() for each acquisition of an rwlock read lock.

PR:		201642
Reviewed by:	avg
Tested by:	Jason Unovitch
MFC after:	3 days
Differential Revision:	https://reviews.freebsd.org/D3073
2015-07-18 00:22:00 +00:00
..
boot/zfs MFV r274273: 2014-11-10 08:20:21 +00:00
compat/opensolaris Create a dedicated function for ensuring that cdir and rdir are populated. 2015-07-11 16:22:48 +00:00
contrib/opensolaris vfs: implement v_holdcnt/v_usecount manipulation using atomic ops 2015-07-16 13:57:05 +00:00
dev Modify lockstat_nsecs() to just return unless lockstat probes are actually 2015-07-18 00:22:00 +00:00