svn commit: r303563 - head/sys/kern

[Mateusz Guzik]

Author: mjg
Date: Sat Jul 30 22:23:31 2016
New Revision: 303563
URL: https://svnweb.freebsd.org/changeset/base/303563

Log:
  sx: increment spin_cnt before cpu_spinwait in xlock
  
  The change is a no-op only done for consistency with the rest of the file.

Modified:
  head/sys/kern/kern_sx.c

Modified: head/sys/kern/kern_sx.c
==============================================================================
--- head/sys/kern/kern_sx.c	Sat Jul 30 22:21:48 2016	(r303562)
+++ head/sys/kern/kern_sx.c	Sat Jul 30 22:23:31 2016	(r303563)
@@ -889,10 +889,10 @@ _sx_slock_hard(struct sx *sx, int opts, 
 				GIANT_SAVE();
 				while (SX_OWNER(sx->sx_lock) == x &&
 				    TD_IS_RUNNING(owner)) {
+					cpu_spinwait();
 #ifdef KDTRACE_HOOKS
 					spin_cnt++;
 #endif
-					cpu_spinwait();
 				}
 				KTR_STATE0(KTR_SCHED, "thread",
 				    sched_tdname(curthread), "running");