From 1f5cdd5a99c34b8330c4f90085ceee0e08126267 Mon Sep 17 00:00:00 2001
From: Jung-uk Kim <jkim@FreeBSD.org>
Date: Tue, 15 Mar 2011 21:45:10 +0000
Subject: [PATCH] Partially revert r219672.  After r198295, kernel need to seed
 randomness as soon as possible for stack protector.  However, dummy
 timecounter does not have enough entropy and we don't need to sacrifice
 Pentium class and later.

Pointed out by:	Maxim Dounin (mdounin at mdounin dot ru)
---
 sys/i386/include/cpu.h | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/sys/i386/include/cpu.h b/sys/i386/include/cpu.h
index 684c254b660c..42424c899f9d 100644
--- a/sys/i386/include/cpu.h
+++ b/sys/i386/include/cpu.h
@@ -69,10 +69,14 @@ void	swi_vm(void *);
 static __inline uint64_t
 get_cyclecount(void)
 {
+#if defined(I486_CPU) || defined(KLD_MODULE)
 	struct bintime bt;
 
 	binuptime(&bt);
 	return ((uint64_t)bt.sec << 56 | bt.frac >> 8);
+#else
+	return (rdtsc());
+#endif
 }
 
 #endif