rcuwait: Let rcuwait_wake_up() return whether or not a task was awoken
Propagating the return value of wake_up_process() back to the caller
can come in handy for future users, such as for statistics or
accounting purposes.
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Message-Id: <20200424054837.5138-3-dave@stgolabs.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/include/linux/rcuwait.h b/include/linux/rcuwait.h
index 2ffe1ee..6ebb232 100644
--- a/include/linux/rcuwait.h
+++ b/include/linux/rcuwait.h
@@ -25,7 +25,7 @@ static inline void rcuwait_init(struct rcuwait *w)
w->task = NULL;
}
-extern void rcuwait_wake_up(struct rcuwait *w);
+extern int rcuwait_wake_up(struct rcuwait *w);
/*
* The caller is responsible for locking around rcuwait_wait_event(),
diff --git a/kernel/exit.c b/kernel/exit.c
index 9f9015f..f3beb63 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -227,8 +227,9 @@ void release_task(struct task_struct *p)
goto repeat;
}
-void rcuwait_wake_up(struct rcuwait *w)
+int rcuwait_wake_up(struct rcuwait *w)
{
+ int ret = 0;
struct task_struct *task;
rcu_read_lock();
@@ -248,8 +249,10 @@ void rcuwait_wake_up(struct rcuwait *w)
task = rcu_dereference(w->task);
if (task)
- wake_up_process(task);
+ ret = wake_up_process(task);
rcu_read_unlock();
+
+ return ret;
}
EXPORT_SYMBOL_GPL(rcuwait_wake_up);