[PATCH] x86: rewrite SMP TSC sync code

make the TSC synchronization code more robust, and unify it between x86_64 and
i386.

The biggest change is the removal of the 'fix up TSCs' code on x86_64 and
i386, in some rare cases it was /causing/ time-warps on SMP systems.

The new code only checks for TSC asynchronity - and if it can prove a
time-warp (if it can observe the TSC going backwards when going from one CPU
to another within a critical section), then the TSC clock-source is turned
off.

The TSC synchronization-checking code also got moved into a separate file.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/arch/x86_64/kernel/Makefile b/arch/x86_64/kernel/Makefile
index ae399458024b..6465eee6d920 100644
--- a/arch/x86_64/kernel/Makefile
+++ b/arch/x86_64/kernel/Makefile
@@ -19,7 +19,7 @@ obj-$(CONFIG_ACPI)		+= acpi/
 obj-$(CONFIG_X86_MSR)           += msr.o
 obj-$(CONFIG_MICROCODE)         += microcode.o
 obj-$(CONFIG_X86_CPUID)         += cpuid.o
-obj-$(CONFIG_SMP)               += smp.o smpboot.o trampoline.o
+obj-$(CONFIG_SMP)               += smp.o smpboot.o trampoline.o tsc_sync.o
 obj-y                           += apic.o  nmi.o
 obj-y                           += io_apic.o mpparse.o \
                 genapic.o genapic_cluster.o genapic_flat.o