powerpc: Fix SMP time initialization problem

We were getting the last_jiffy per-cpu variable set ahead of the current
timebase in smp_space_timers on SMP machines.  This caused the loop in
timer_interrupt to loop virtually forever, since tb_ticks_since assumes
that it will never be called with the timebase behind the last_jiffy
value.

Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 2 insertions, 0 deletions

diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c
index 386006b3d616..260b6ecd26a9 100644
--- a/arch/powerpc/kernel/time.c
+++ b/arch/powerpc/kernel/time.c
@@ -484,6 +484,8 @@ void __init smp_space_timers(unsigned int max_cpus)
         unsigned long offset = tb_ticks_per_jiffy / max_cpus;
         unsigned long previous_tb = per_cpu(last_jiffy, boot_cpuid);
 
+        /* make sure tb > per_cpu(last_jiffy, cpu) for all cpus always */
+        previous_tb -= tb_ticks_per_jiffy;
         for_each_cpu(i) {
                 if (i != boot_cpuid) {
                         previous_tb += offset;