stop_machine(): stop_machine_run() changed to use cpu mask

Instead of a "cpu" arg with magic values NR_CPUS (any cpu) and ~0 (all
cpus), pass a cpumask_t.  Allow NULL for the common case (where we
don't care which CPU the function is run on): temporary cpumask_t's
are usually considered bad for stack space.

This deprecates stop_machine_run, to be removed soon when all the
callers are dead.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

1 files changed, 2 insertions, 1 deletions

diff --git a/kernel/cpu.c b/kernel/cpu.c
index 53cf508f975a..29510d68338a 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -248,8 +248,9 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen)
         cpus_setall(tmp);
         cpu_clear(cpu, tmp);
         set_cpus_allowed_ptr(current, &tmp);
+        tmp = cpumask_of_cpu(cpu);
 
-        err = __stop_machine_run(take_cpu_down, &tcd_param, cpu);
+        err = __stop_machine(take_cpu_down, &tcd_param, &tmp);
         if (err) {
                 /* CPU didn't die: tell everyone.  Can't complain. */
                 if (raw_notifier_call_chain(&cpu_chain, CPU_DOWN_FAILED | mod,