svn commit: r336095 - head/sys/sys

[Matt Macy]

Author: mmacy
Date: Sun Jul  8 19:35:29 2018
New Revision: 336095
URL: https://svnweb.freebsd.org/changeset/base/336095

Log:
  critical_{enter, exit}: add missing compiler barrier
  
  Reported by:	markj

Modified:
  head/sys/sys/systm.h

Modified: head/sys/sys/systm.h
==============================================================================
--- head/sys/sys/systm.h	Sun Jul  8 18:44:42 2018	(r336094)
+++ head/sys/sys/systm.h	Sun Jul  8 19:35:29 2018	(r336095)
@@ -238,6 +238,7 @@ critical_enter(void)
 
 	td = (struct thread_lite *)curthread;
 	td->td_critnest++;
+	__compiler_membar();
 }
 
 static __inline void
@@ -248,6 +249,7 @@ critical_exit(void)
 	td = (struct thread_lite *)curthread;
 	KASSERT(td->td_critnest != 0,
 	    ("critical_exit: td_critnest == 0"));
+	__compiler_membar();
 	td->td_critnest--;
 	__compiler_membar();
 	if (__predict_false(td->td_owepreempt))