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-rw-r--r--block/cfq-iosched.c34
1 files changed, 20 insertions, 14 deletions
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index b0b754a6882..a55a9bd75bd 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -154,6 +154,8 @@ struct cfq_queue {
unsigned long rb_key;
/* prio tree member */
struct rb_node p_node;
+ /* prio tree root we belong to, if any */
+ struct rb_root *p_root;
/* sorted list of pending requests */
struct rb_root sort_list;
/* if fifo isn't expired, next request to serve */
@@ -558,10 +560,10 @@ static void cfq_service_tree_add(struct cfq_data *cfqd, struct cfq_queue *cfqq,
}
static struct cfq_queue *
-cfq_prio_tree_lookup(struct cfq_data *cfqd, int ioprio, sector_t sector,
- struct rb_node **ret_parent, struct rb_node ***rb_link)
+cfq_prio_tree_lookup(struct cfq_data *cfqd, struct rb_root *root,
+ sector_t sector, struct rb_node **ret_parent,
+ struct rb_node ***rb_link)
{
- struct rb_root *root = &cfqd->prio_trees[ioprio];
struct rb_node **p, *parent;
struct cfq_queue *cfqq = NULL;
@@ -595,24 +597,27 @@ cfq_prio_tree_lookup(struct cfq_data *cfqd, int ioprio, sector_t sector,
static void cfq_prio_tree_add(struct cfq_data *cfqd, struct cfq_queue *cfqq)
{
- struct rb_root *root = &cfqd->prio_trees[cfqq->ioprio];
struct rb_node **p, *parent;
struct cfq_queue *__cfqq;
- if (!RB_EMPTY_NODE(&cfqq->p_node))
- rb_erase_init(&cfqq->p_node, root);
+ if (cfqq->p_root) {
+ rb_erase(&cfqq->p_node, cfqq->p_root);
+ cfqq->p_root = NULL;
+ }
if (cfq_class_idle(cfqq))
return;
if (!cfqq->next_rq)
return;
- __cfqq = cfq_prio_tree_lookup(cfqd, cfqq->ioprio, cfqq->next_rq->sector,
+ cfqq->p_root = &cfqd->prio_trees[cfqq->org_ioprio];
+ __cfqq = cfq_prio_tree_lookup(cfqd, cfqq->p_root, cfqq->next_rq->sector,
&parent, &p);
if (!__cfqq) {
rb_link_node(&cfqq->p_node, parent, p);
- rb_insert_color(&cfqq->p_node, root);
- }
+ rb_insert_color(&cfqq->p_node, cfqq->p_root);
+ } else
+ cfqq->p_root = NULL;
}
/*
@@ -657,8 +662,10 @@ static void cfq_del_cfqq_rr(struct cfq_data *cfqd, struct cfq_queue *cfqq)
if (!RB_EMPTY_NODE(&cfqq->rb_node))
cfq_rb_erase(&cfqq->rb_node, &cfqd->service_tree);
- if (!RB_EMPTY_NODE(&cfqq->p_node))
- rb_erase_init(&cfqq->p_node, &cfqd->prio_trees[cfqq->ioprio]);
+ if (cfqq->p_root) {
+ rb_erase(&cfqq->p_node, cfqq->p_root);
+ cfqq->p_root = NULL;
+ }
BUG_ON(!cfqd->busy_queues);
cfqd->busy_queues--;
@@ -965,7 +972,7 @@ static inline int cfq_rq_close(struct cfq_data *cfqd, struct request *rq)
static struct cfq_queue *cfqq_close(struct cfq_data *cfqd,
struct cfq_queue *cur_cfqq)
{
- struct rb_root *root = &cfqd->prio_trees[cur_cfqq->ioprio];
+ struct rb_root *root = &cfqd->prio_trees[cur_cfqq->org_ioprio];
struct rb_node *parent, *node;
struct cfq_queue *__cfqq;
sector_t sector = cfqd->last_position;
@@ -977,8 +984,7 @@ static struct cfq_queue *cfqq_close(struct cfq_data *cfqd,
* First, if we find a request starting at the end of the last
* request, choose it.
*/
- __cfqq = cfq_prio_tree_lookup(cfqd, cur_cfqq->ioprio,
- sector, &parent, NULL);
+ __cfqq = cfq_prio_tree_lookup(cfqd, root, sector, &parent, NULL);
if (__cfqq)
return __cfqq;