The hrtimer code is interested whether the added timer is the first one to expire and whether the removed timer was the last one in the tree. The add/del routines have that information already. So we can return it right away instead of reevaluating it at the call site. Signed-off-by: Thomas Gleixner Cc: John Stultz --- include/linux/timerqueue.h | 8 ++++---- lib/timerqueue.c | 10 +++++++--- 2 files changed, 11 insertions(+), 7 deletions(-) Index: linux/include/linux/timerqueue.h =================================================================== --- linux.orig/include/linux/timerqueue.h +++ linux/include/linux/timerqueue.h @@ -16,10 +16,10 @@ struct timerqueue_head { }; -extern void timerqueue_add(struct timerqueue_head *head, - struct timerqueue_node *node); -extern void timerqueue_del(struct timerqueue_head *head, - struct timerqueue_node *node); +extern bool timerqueue_add(struct timerqueue_head *head, + struct timerqueue_node *node); +extern bool timerqueue_del(struct timerqueue_head *head, + struct timerqueue_node *node); extern struct timerqueue_node *timerqueue_iterate_next( struct timerqueue_node *node); Index: linux/lib/timerqueue.c =================================================================== --- linux.orig/lib/timerqueue.c +++ linux/lib/timerqueue.c @@ -36,7 +36,7 @@ * Adds the timer node to the timerqueue, sorted by the * node's expires value. */ -void timerqueue_add(struct timerqueue_head *head, struct timerqueue_node *node) +bool timerqueue_add(struct timerqueue_head *head, struct timerqueue_node *node) { struct rb_node **p = &head->head.rb_node; struct rb_node *parent = NULL; @@ -56,8 +56,11 @@ void timerqueue_add(struct timerqueue_he rb_link_node(&node->node, parent, p); rb_insert_color(&node->node, &head->head); - if (!head->next || node->expires.tv64 < head->next->expires.tv64) + if (!head->next || node->expires.tv64 < head->next->expires.tv64) { head->next = node; + return true; + } + return false; } EXPORT_SYMBOL_GPL(timerqueue_add); @@ -69,7 +72,7 @@ EXPORT_SYMBOL_GPL(timerqueue_add); * * Removes the timer node from the timerqueue. */ -void timerqueue_del(struct timerqueue_head *head, struct timerqueue_node *node) +bool timerqueue_del(struct timerqueue_head *head, struct timerqueue_node *node) { WARN_ON_ONCE(RB_EMPTY_NODE(&node->node)); @@ -82,6 +85,7 @@ void timerqueue_del(struct timerqueue_he } rb_erase(&node->node, &head->head); RB_CLEAR_NODE(&node->node); + return head->next != NULL; } EXPORT_SYMBOL_GPL(timerqueue_del);