[PATCH] deadline-iosched: migrate to using the elevator rb functions
This removes the rbtree handling from deadline.
Signed-off-by: Jens Axboe <axboe@suse.de>
diff --git a/block/deadline-iosched.c b/block/deadline-iosched.c
index b66e820..8300ba1 100644
--- a/block/deadline-iosched.c
+++ b/block/deadline-iosched.c
@@ -57,12 +57,6 @@
* pre-request data.
*/
struct deadline_rq {
- /*
- * rbtree index, key is the starting offset
- */
- struct rb_node rb_node;
- sector_t rb_key;
-
struct request *request;
/*
@@ -78,108 +72,38 @@
#define RQ_DATA(rq) ((struct deadline_rq *) (rq)->elevator_private)
-/*
- * rb tree support functions
- */
-#define rb_entry_drq(node) rb_entry((node), struct deadline_rq, rb_node)
-#define DRQ_RB_ROOT(dd, drq) (&(dd)->sort_list[rq_data_dir((drq)->request)])
-#define rq_rb_key(rq) (rq)->sector
-
-static struct deadline_rq *
-__deadline_add_drq_rb(struct deadline_data *dd, struct deadline_rq *drq)
-{
- struct rb_node **p = &DRQ_RB_ROOT(dd, drq)->rb_node;
- struct rb_node *parent = NULL;
- struct deadline_rq *__drq;
-
- while (*p) {
- parent = *p;
- __drq = rb_entry_drq(parent);
-
- if (drq->rb_key < __drq->rb_key)
- p = &(*p)->rb_left;
- else if (drq->rb_key > __drq->rb_key)
- p = &(*p)->rb_right;
- else
- return __drq;
- }
-
- rb_link_node(&drq->rb_node, parent, p);
- return NULL;
-}
+#define RQ_RB_ROOT(dd, rq) (&(dd)->sort_list[rq_data_dir((rq))])
+#define DRQ_RB_ROOT(dd, drq) RQ_RB_ROOT((drq)->request)
static void
-deadline_add_drq_rb(struct deadline_data *dd, struct deadline_rq *drq)
+deadline_add_drq_rb(struct deadline_data *dd, struct request *rq)
{
- struct deadline_rq *__alias;
-
- drq->rb_key = rq_rb_key(drq->request);
+ struct rb_root *root = RQ_RB_ROOT(dd, rq);
+ struct request *__alias;
retry:
- __alias = __deadline_add_drq_rb(dd, drq);
- if (!__alias) {
- rb_insert_color(&drq->rb_node, DRQ_RB_ROOT(dd, drq));
- return;
+ __alias = elv_rb_add(root, rq);
+ if (unlikely(__alias)) {
+ deadline_move_request(dd, RQ_DATA(__alias));
+ goto retry;
}
-
- deadline_move_request(dd, __alias);
- goto retry;
}
static inline void
deadline_del_drq_rb(struct deadline_data *dd, struct deadline_rq *drq)
{
- const int data_dir = rq_data_dir(drq->request);
+ struct request *rq = drq->request;
+ const int data_dir = rq_data_dir(rq);
if (dd->next_drq[data_dir] == drq) {
- struct rb_node *rbnext = rb_next(&drq->rb_node);
+ struct rb_node *rbnext = rb_next(&rq->rb_node);
dd->next_drq[data_dir] = NULL;
if (rbnext)
- dd->next_drq[data_dir] = rb_entry_drq(rbnext);
+ dd->next_drq[data_dir] = RQ_DATA(rb_entry_rq(rbnext));
}
- BUG_ON(!RB_EMPTY_NODE(&drq->rb_node));
- rb_erase(&drq->rb_node, DRQ_RB_ROOT(dd, drq));
- RB_CLEAR_NODE(&drq->rb_node);
-}
-
-static struct request *
-deadline_find_drq_rb(struct deadline_data *dd, sector_t sector, int data_dir)
-{
- struct rb_node *n = dd->sort_list[data_dir].rb_node;
- struct deadline_rq *drq;
-
- while (n) {
- drq = rb_entry_drq(n);
-
- if (sector < drq->rb_key)
- n = n->rb_left;
- else if (sector > drq->rb_key)
- n = n->rb_right;
- else
- return drq->request;
- }
-
- return NULL;
-}
-
-/*
- * deadline_find_first_drq finds the first (lowest sector numbered) request
- * for the specified data_dir. Used to sweep back to the start of the disk
- * (1-way elevator) after we process the last (highest sector) request.
- */
-static struct deadline_rq *
-deadline_find_first_drq(struct deadline_data *dd, int data_dir)
-{
- struct rb_node *n = dd->sort_list[data_dir].rb_node;
-
- for (;;) {
- if (n->rb_left == NULL)
- return rb_entry_drq(n);
-
- n = n->rb_left;
- }
+ elv_rb_del(RQ_RB_ROOT(dd, rq), rq);
}
/*
@@ -192,7 +116,7 @@
struct deadline_rq *drq = RQ_DATA(rq);
const int data_dir = rq_data_dir(drq->request);
- deadline_add_drq_rb(dd, drq);
+ deadline_add_drq_rb(dd, rq);
/*
* set expire time (only used for reads) and add to fifo list
@@ -224,11 +148,11 @@
* check for front merge
*/
if (dd->front_merges) {
- sector_t rb_key = bio->bi_sector + bio_sectors(bio);
+ sector_t sector = bio->bi_sector + bio_sectors(bio);
- __rq = deadline_find_drq_rb(dd, rb_key, bio_data_dir(bio));
+ __rq = elv_rb_find(&dd->sort_list[bio_data_dir(bio)], sector);
if (__rq) {
- BUG_ON(rb_key != rq_rb_key(__rq));
+ BUG_ON(sector != __rq->sector);
if (elv_rq_merge_ok(__rq, bio)) {
ret = ELEVATOR_FRONT_MERGE;
@@ -243,17 +167,17 @@
return ret;
}
-static void deadline_merged_request(request_queue_t *q, struct request *req)
+static void deadline_merged_request(request_queue_t *q, struct request *req,
+ int type)
{
struct deadline_data *dd = q->elevator->elevator_data;
- struct deadline_rq *drq = RQ_DATA(req);
/*
* if the merge was a front merge, we need to reposition request
*/
- if (rq_rb_key(req) != drq->rb_key) {
- deadline_del_drq_rb(dd, drq);
- deadline_add_drq_rb(dd, drq);
+ if (type == ELEVATOR_FRONT_MERGE) {
+ elv_rb_del(RQ_RB_ROOT(dd, req), req);
+ deadline_add_drq_rb(dd, req);
}
}
@@ -261,18 +185,12 @@
deadline_merged_requests(request_queue_t *q, struct request *req,
struct request *next)
{
- struct deadline_data *dd = q->elevator->elevator_data;
struct deadline_rq *drq = RQ_DATA(req);
struct deadline_rq *dnext = RQ_DATA(next);
BUG_ON(!drq);
BUG_ON(!dnext);
- if (rq_rb_key(req) != drq->rb_key) {
- deadline_del_drq_rb(dd, drq);
- deadline_add_drq_rb(dd, drq);
- }
-
/*
* if dnext expires before drq, assign its expire time to drq
* and move into dnext position (dnext will be deleted) in fifo
@@ -308,14 +226,15 @@
static void
deadline_move_request(struct deadline_data *dd, struct deadline_rq *drq)
{
- const int data_dir = rq_data_dir(drq->request);
- struct rb_node *rbnext = rb_next(&drq->rb_node);
+ struct request *rq = drq->request;
+ const int data_dir = rq_data_dir(rq);
+ struct rb_node *rbnext = rb_next(&rq->rb_node);
dd->next_drq[READ] = NULL;
dd->next_drq[WRITE] = NULL;
if (rbnext)
- dd->next_drq[data_dir] = rb_entry_drq(rbnext);
+ dd->next_drq[data_dir] = RQ_DATA(rb_entry_rq(rbnext));
dd->last_sector = drq->request->sector + drq->request->nr_sectors;
@@ -426,13 +345,17 @@
*/
drq = dd->next_drq[data_dir];
} else {
+ struct rb_node *n;
+
/*
* The last req was the other direction or we have run out of
* higher-sectored requests. Go back to the lowest sectored
* request (1 way elevator) and start a new batch.
*/
dd->batching = 0;
- drq = deadline_find_first_drq(dd, data_dir);
+ n = rb_first(&dd->sort_list[data_dir]);
+ if (n)
+ drq = RQ_DATA(rb_entry_rq(n));
}
dispatch_request:
@@ -453,30 +376,6 @@
&& list_empty(&dd->fifo_list[READ]);
}
-static struct request *
-deadline_former_request(request_queue_t *q, struct request *rq)
-{
- struct deadline_rq *drq = RQ_DATA(rq);
- struct rb_node *rbprev = rb_prev(&drq->rb_node);
-
- if (rbprev)
- return rb_entry_drq(rbprev)->request;
-
- return NULL;
-}
-
-static struct request *
-deadline_latter_request(request_queue_t *q, struct request *rq)
-{
- struct deadline_rq *drq = RQ_DATA(rq);
- struct rb_node *rbnext = rb_next(&drq->rb_node);
-
- if (rbnext)
- return rb_entry_drq(rbnext)->request;
-
- return NULL;
-}
-
static void deadline_exit_queue(elevator_t *e)
{
struct deadline_data *dd = e->elevator_data;
@@ -542,7 +441,6 @@
drq = mempool_alloc(dd->drq_pool, gfp_mask);
if (drq) {
memset(drq, 0, sizeof(*drq));
- RB_CLEAR_NODE(&drq->rb_node);
drq->request = rq;
INIT_LIST_HEAD(&drq->fifo);
@@ -633,8 +531,8 @@
.elevator_dispatch_fn = deadline_dispatch_requests,
.elevator_add_req_fn = deadline_add_request,
.elevator_queue_empty_fn = deadline_queue_empty,
- .elevator_former_req_fn = deadline_former_request,
- .elevator_latter_req_fn = deadline_latter_request,
+ .elevator_former_req_fn = elv_rb_former_request,
+ .elevator_latter_req_fn = elv_rb_latter_request,
.elevator_set_req_fn = deadline_set_request,
.elevator_put_req_fn = deadline_put_request,
.elevator_init_fn = deadline_init_queue,