[PATCH] x86_64: Don't try to synchronize the TSC over CPUs on Intel CPUs at boot.
They already do this in hardware and the Linux algorithm
actually adds errors.
Cc: mingo@elte.hu
Cc: rohit.seth@intel.com
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/x86_64/kernel/time.c b/arch/x86_64/kernel/time.c
index 211bf0e..f8d4b69 100644
--- a/arch/x86_64/kernel/time.c
+++ b/arch/x86_64/kernel/time.c
@@ -953,7 +953,7 @@
* Make an educated guess if the TSC is trustworthy and synchronized
* over all CPUs.
*/
-static __init int unsynchronized_tsc(void)
+__init int unsynchronized_tsc(void)
{
#ifdef CONFIG_SMP
if (oem_force_hpet_timer())
@@ -964,7 +964,7 @@
return 0;
#endif
/* Assume multi socket systems are not synchronized */
- return num_online_cpus() > 1;
+ return num_present_cpus() > 1;
}
/*