x86, tsc: Fix a preemption leak in restore_sched_clock_state()

Doh, a real life genuine preemption leak..

This caused a suspend failure.

Reported-bisected-and-tested-by-the-invaluable: Jeff Chua <jeff.chua.linux@gmail.com>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Nico Schottelius <nico-linux-20100709@schottelius.org>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Florian Pritz <flo@xssn.at>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Len Brown <lenb@kernel.org>
Cc: <stable@kernel.org> # Greg, please apply after: cd7240c ("x86, tsc, sched: Recompute cyc2ns_offset's during resume from")
sleep states
LKML-Reference: <1284150773.402.122.camel@laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
index d632934cb6386947352650f262745eb3c93c68ce..26a863a9c2a815ec797b6211cd3de5e0b9cbed8e 100644 (file)
--- a/arch/x86/kernel/tsc.c
+++ b/arch/x86/kernel/tsc.c
@@ -655,7 +655,7 @@ void restore_sched_clock_state(void)
 
        local_irq_save(flags);
 
-       get_cpu_var(cyc2ns_offset) = 0;
+       __get_cpu_var(cyc2ns_offset) = 0;
        offset = cyc2ns_suspend - sched_clock();
 
        for_each_possible_cpu(cpu)