[PATCH] rbtree: support functions used by the io schedulers

They all duplicate macros to check for empty root and/or node, and
clearing a node. So put those in rbtree.h.

Signed-off-by: Jens Axboe <axboe@suse.de>

1 files changed, 7 insertions, 10 deletions

diff --git a/block/as-iosched.c b/block/as-iosched.c
index 56c99fa037df..1ec5df466708 100644
--- a/block/as-iosched.c
+++ b/block/as-iosched.c
@@ -347,9 +347,6 @@ static struct request *as_find_arq_hash(struct as_data *ad, sector_t offset)
 /*
  * rb tree support functions
  */
-#define RB_EMPTY(root)  ((root)->rb_node == NULL)
-#define ON_RB(node)     (rb_parent(node) != node)
-#define RB_CLEAR(node)  (rb_set_parent(node, node))
 #define rb_entry_arq(node)      rb_entry((node), struct as_rq, rb_node)
 #define ARQ_RB_ROOT(ad, arq)    (&(ad)->sort_list[(arq)->is_sync])
 #define rq_rb_key(rq)           (rq)->sector
@@ -418,13 +415,13 @@ static void as_add_arq_rb(struct as_data *ad, struct as_rq *arq)
 
 static inline void as_del_arq_rb(struct as_data *ad, struct as_rq *arq)
 {
-        if (!ON_RB(&arq->rb_node)) {
+        if (!RB_EMPTY_NODE(&arq->rb_node)) {
                 WARN_ON(1);
                 return;
         }
 
         rb_erase(&arq->rb_node, ARQ_RB_ROOT(ad, arq));
-        RB_CLEAR(&arq->rb_node);
+        RB_CLEAR_NODE(&arq->rb_node);
 }
 
 static struct request *
@@ -545,7 +542,7 @@ static struct as_rq *as_find_next_arq(struct as_data *ad, struct as_rq *last)
         struct rb_node *rbprev = rb_prev(&last->rb_node);
         struct as_rq *arq_next, *arq_prev;
 
-        BUG_ON(!ON_RB(&last->rb_node));
+        BUG_ON(!RB_EMPTY_NODE(&last->rb_node));
 
         if (rbprev)
                 arq_prev = rb_entry_arq(rbprev);
@@ -1122,7 +1119,7 @@ static void as_move_to_dispatch(struct as_data *ad, struct as_rq *arq)
         struct request *rq = arq->request;
         const int data_dir = arq->is_sync;
 
-        BUG_ON(!ON_RB(&arq->rb_node));
+        BUG_ON(!RB_EMPTY_NODE(&arq->rb_node));
 
         as_antic_stop(ad);
         ad->antic_status = ANTIC_OFF;
@@ -1247,7 +1244,7 @@ static int as_dispatch_request(request_queue_t *q, int force)
          */
 
         if (reads) {
-                BUG_ON(RB_EMPTY(&ad->sort_list[REQ_SYNC]));
+                BUG_ON(RB_EMPTY_ROOT(&ad->sort_list[REQ_SYNC]));
 
                 if (writes && ad->batch_data_dir == REQ_SYNC)
                         /*
@@ -1271,7 +1268,7 @@ static int as_dispatch_request(request_queue_t *q, int force)
 
         if (writes) {
 dispatch_writes:
-                BUG_ON(RB_EMPTY(&ad->sort_list[REQ_ASYNC]));
+                BUG_ON(RB_EMPTY_ROOT(&ad->sort_list[REQ_ASYNC]));
 
                 if (ad->batch_data_dir == REQ_SYNC) {
                         ad->changed_batch = 1;
@@ -1591,7 +1588,7 @@ static int as_set_request(request_queue_t *q, struct request *rq,
 
         if (arq) {
                 memset(arq, 0, sizeof(*arq));
-                RB_CLEAR(&arq->rb_node);
+                RB_CLEAR_NODE(&arq->rb_node);
                 arq->request = rq;
                 arq->state = AS_RQ_PRESCHED;
                 arq->io_context = NULL;