staging: lustre: disable preempt while sampling processor id.

staging: lustre: disable preempt while sampling processor id.

Calling smp_processor_id() without disabling preemption
triggers a warning (if CONFIG_DEBUG_PREEMPT).
I think the result of cfs_cpt_current() is only used as a hint for
load balancing, rather than as a precise and stable indicator of
the current CPU.  So it doesn't need to be called with
preemption disabled.

So disable preemption inside cfs_cpt_current() to silence the warning.

Signed-off-by: NeilBrown <[email protected]>
Reviewed-by: Andreas Dilger <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>