Required to figure out whether the entry is the only one in the hlist. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Chris Mason <clm@fb.com> Cc: Eric Dumazet <edumazet@google.com> Cc: rt@linutronix.de Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Arjan van de Ven <arjan@infradead.org> --- include/linux/list.h | 10 ++++++++++ 1 file changed, 10 insertions(+) --- a/include/linux/list.h +++ b/include/linux/list.h @@ -679,6 +679,16 @@ static inline bool hlist_fake(struct hli } /* + * Check whether the node is the only node of the head without + * accessing head. + */ +static inline bool hlist_is_singular_node(struct hlist_node *n, + struct hlist_head *h) +{ + return !n->next && n->pprev == &h->first; +} + +/* * Move a list from one list head to another. Fixup the pprev * reference of the first entry if it exists. */