Impact: remove cpumask_t from stack.
We should not try to save and restore cpus_allowed on current.
We can't use work_on_cpu() here, since it's in the hotplug cpu path
(if anyone else tries to get the hotplug lock from a workqueue we
could deadlock against them).
Fortunately, we can just use smp_call_function_single() since the
function can run from an interrupt.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
b2bb855491