[RFC PATCH 1/4] stop_machine: Move cpu_stop_done into stop_machine.h

[Yafang Shao]

Move struct cpu_stop_done into the stop_machine.h, then it can be resued
by the functions outside of stop_maichine.c.

Signed-off-by: Yafang Shao <laoar.shao@xxxxxxxxx>
Cc: Valentin Schneider <valentin.schneider@xxxxxxx>
Cc: Vincent Guittot <vincent.guittot@xxxxxxxxxx>
Cc: Dietmar Eggemann <dietmar.eggemann@xxxxxxx>
---
 include/linux/stop_machine.h | 12 ++++++++++++
 kernel/stop_machine.c        | 14 ++------------
 2 files changed, 14 insertions(+), 12 deletions(-)

diff --git a/include/linux/stop_machine.h b/include/linux/stop_machine.h
index 46fb3ebdd16e..b1234cb6ab70 100644
--- a/include/linux/stop_machine.h
+++ b/include/linux/stop_machine.h
@@ -20,6 +20,15 @@
 typedef int (*cpu_stop_fn_t)(void *arg);
 
 #ifdef CONFIG_SMP
+/*
+ * Structure to determine completion condition and record errors.  May
+ * be shared by works on different cpus.
+ */
+struct cpu_stop_done {
+	atomic_t		nr_todo;	/* nr left to execute */
+	int			ret;		/* collected return value */
+	struct completion	completion;	/* fired if nr_todo reaches 0 */
+};
 
 struct cpu_stop_work {
 	struct list_head	list;		/* cpu_stopper->works */
@@ -29,6 +38,9 @@ struct cpu_stop_work {
 	struct cpu_stop_done	*done;
 };
 
+void cpu_stop_init_done(struct cpu_stop_done *done, unsigned int nr_todo);
+void cpu_stop_signal_done(struct cpu_stop_done *done);
+
 int stop_one_cpu(unsigned int cpu, cpu_stop_fn_t fn, void *arg);
 int stop_two_cpus(unsigned int cpu1, unsigned int cpu2, cpu_stop_fn_t fn, void *arg);
 bool stop_one_cpu_nowait(unsigned int cpu, cpu_stop_fn_t fn, void *arg,
diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c
index cbc30271ea4d..cc94eb7d2c5c 100644
--- a/kernel/stop_machine.c
+++ b/kernel/stop_machine.c
@@ -23,16 +23,6 @@
 #include <linux/nmi.h>
 #include <linux/sched/wake_q.h>
 
-/*
- * Structure to determine completion condition and record errors.  May
- * be shared by works on different cpus.
- */
-struct cpu_stop_done {
-	atomic_t		nr_todo;	/* nr left to execute */
-	int			ret;		/* collected return value */
-	struct completion	completion;	/* fired if nr_todo reaches 0 */
-};
-
 /* the actual stopper, one per every possible cpu, enabled on online cpus */
 struct cpu_stopper {
 	struct task_struct	*thread;
@@ -67,7 +57,7 @@ void print_stop_info(const char *log_lvl, struct task_struct *task)
 static DEFINE_MUTEX(stop_cpus_mutex);
 static bool stop_cpus_in_progress;
 
-static void cpu_stop_init_done(struct cpu_stop_done *done, unsigned int nr_todo)
+void cpu_stop_init_done(struct cpu_stop_done *done, unsigned int nr_todo)
 {
 	memset(done, 0, sizeof(*done));
 	atomic_set(&done->nr_todo, nr_todo);
@@ -75,7 +65,7 @@ static void cpu_stop_init_done(struct cpu_stop_done *done, unsigned int nr_todo)
 }
 
 /* signal completion unless @done is NULL */
-static void cpu_stop_signal_done(struct cpu_stop_done *done)
+void cpu_stop_signal_done(struct cpu_stop_done *done)
 {
 	if (atomic_dec_and_test(&done->nr_todo))
 		complete(&done->completion);
-- 
2.17.1