[patch V5 09/72] sched/wake_q: Provide WAKE_Q_HEAD_INITIALIZER

From: Thomas Gleixner
Date: Sun Aug 15 2021 - 17:29:03 EST


From: Thomas Gleixner <tglx@xxxxxxxxxxxxx>

The RT specific spin/rwlock implementation requires special handling of the
to be woken waiters. Provide a WAKE_Q_HEAD_INITIALIZER which can be used by
the rtmutex code to implement a RT aware wake_q derivative.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
---
include/linux/sched/wake_q.h | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
---
--- a/include/linux/sched/wake_q.h
+++ b/include/linux/sched/wake_q.h
@@ -42,8 +42,11 @@ struct wake_q_head {

#define WAKE_Q_TAIL ((struct wake_q_node *) 0x01)

-#define DEFINE_WAKE_Q(name) \
- struct wake_q_head name = { WAKE_Q_TAIL, &name.first }
+#define WAKE_Q_HEAD_INITIALIZER(name) \
+ { WAKE_Q_TAIL, &name.first }
+
+#define DEFINE_WAKE_Q(name) \
+ struct wake_q_head name = WAKE_Q_HEAD_INITIALIZER(name)

static inline void wake_q_init(struct wake_q_head *head)
{