[PATCH] x86_64: fix sync before RDTSC on Intel cpus
authorSiddha, Suresh B <suresh.b.siddha@intel.com>
Tue, 11 Apr 2006 10:54:42 +0000 (12:54 +0200)
committerLinus Torvalds <torvalds@g5.osdl.org>
Tue, 11 Apr 2006 13:38:57 +0000 (06:38 -0700)
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>
include/asm-x86_64/timex.h

index f18443fcdf04c9a0570727e82b2f6d2d221d07f2..b9e5320b76252f06d86fac9f1ac36eeaaa41233b 100644 (file)
@@ -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;