From: Siddha, Suresh B <suresh.b.siddha@intel.com>
Date: Tue, 11 Apr 2006 10:54:42 +0000 (+0200)
Subject: [PATCH] x86_64: fix sync before RDTSC on Intel cpus
X-Git-Tag: v2.6.17-rc2~104
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e4cff6ac78e9c3bbb90c0e01b20418eeae0c6b52;p=linux-2.6

[PATCH] x86_64: fix sync before RDTSC on Intel cpus

Commit c818a18146997d1356a4840b0c01f1168c16c8a4 didn't do the expected
thing.  This fix will remove the additional sync(cpuid) before RDTSC on
Intel platforms..

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
---

diff --git a/include/asm-x86_64/timex.h b/include/asm-x86_64/timex.h
index f18443fcdf..b9e5320b76 100644
--- a/include/asm-x86_64/timex.h
+++ b/include/asm-x86_64/timex.h
@@ -33,7 +33,7 @@ static __always_inline cycles_t get_cycles_sync(void)
 	unsigned eax;
 	/* Don't do an additional sync on CPUs where we know
 	   RDTSC is already synchronous. */
-	alternative_io(ASM_NOP2, "cpuid", X86_FEATURE_SYNC_RDTSC,
+	alternative_io("cpuid", ASM_NOP2, X86_FEATURE_SYNC_RDTSC,
 			  "=a" (eax), "0" (1) : "ebx","ecx","edx","memory");
 	rdtscll(ret);
 	return ret;