[PATCH v5 17/21] llist: Add nonatomic __llist_add() and __llist_dell_all()

[Masami Hiramatsu <mhiramat@xxxxxxxxxx>]

From: Peter Zijlstra <peterz@xxxxxxxxxxxxx>

Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
---
 drivers/gpu/drm/i915/i915_request.c |    6 ------
 include/linux/llist.h               |   23 +++++++++++++++++++++++
 2 files changed, 23 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c
index 0b2fe55e6194..0e851b925c8c 100644
--- a/drivers/gpu/drm/i915/i915_request.c
+++ b/drivers/gpu/drm/i915/i915_request.c
@@ -357,12 +357,6 @@ void i915_request_retire_upto(struct i915_request *rq)
 	} while (i915_request_retire(tmp) && tmp != rq);
 }
 
-static void __llist_add(struct llist_node *node, struct llist_head *head)
-{
-	node->next = head->first;
-	head->first = node;
-}
-
 static struct i915_request * const *
 __engine_active(struct intel_engine_cs *engine)
 {
diff --git a/include/linux/llist.h b/include/linux/llist.h
index 2e9c7215882b..24f207b0190b 100644
--- a/include/linux/llist.h
+++ b/include/linux/llist.h
@@ -197,6 +197,16 @@ static inline struct llist_node *llist_next(struct llist_node *node)
 extern bool llist_add_batch(struct llist_node *new_first,
 			    struct llist_node *new_last,
 			    struct llist_head *head);
+
+static inline bool __llist_add_batch(struct llist_node *new_first,
+				     struct llist_node *new_last,
+				     struct llist_head *head)
+{
+	new_last->next = head->first;
+	head->first = new_first;
+	return new_last->next == NULL;
+}
+
 /**
  * llist_add - add a new entry
  * @new:	new entry to be added
@@ -209,6 +219,11 @@ static inline bool llist_add(struct llist_node *new, struct llist_head *head)
 	return llist_add_batch(new, new, head);
 }
 
+static inline bool __llist_add(struct llist_node *new, struct llist_head *head)
+{
+	return __llist_add_batch(new, new, head);
+}
+
 /**
  * llist_del_all - delete all entries from lock-less list
  * @head:	the head of lock-less list to delete all entries
@@ -222,6 +237,14 @@ static inline struct llist_node *llist_del_all(struct llist_head *head)
 	return xchg(&head->first, NULL);
 }
 
+static inline struct llist_node *__llist_del_all(struct llist_head *head)
+{
+	struct llist_node *first = head->first;
+
+	head->first = NULL;
+	return first;
+}
+
 extern struct llist_node *llist_del_first(struct llist_head *head);
 
 struct llist_node *llist_reverse_order(struct llist_node *head);