[PATCH] generic dispatch fixes
- Split elv_dispatch_insert() into two functions
- Rename rq_last_sector() to rq_end_sector()
Signed-off-by: Jens Axboe <axboe@suse.de>
diff --git a/drivers/block/elevator.c b/drivers/block/elevator.c
index a275559..237e43d 100644
--- a/drivers/block/elevator.c
+++ b/drivers/block/elevator.c
@@ -40,11 +40,6 @@
static DEFINE_SPINLOCK(elv_list_lock);
static LIST_HEAD(elv_list);
-static inline sector_t rq_last_sector(struct request *rq)
-{
- return rq->sector + rq->nr_sectors;
-}
-
/*
* can we safely merge with this request?
*/
@@ -148,7 +143,7 @@
INIT_LIST_HEAD(&q->queue_head);
q->last_merge = NULL;
q->elevator = eq;
- q->last_sector = 0;
+ q->end_sector = 0;
q->boundary_rq = NULL;
q->max_back_kb = 0;
@@ -233,29 +228,25 @@
kfree(e);
}
+void elv_dispatch_insert_tail(request_queue_t *q, struct request *rq)
+{
+}
+
/*
* Insert rq into dispatch queue of q. Queue lock must be held on
* entry. If sort != 0, rq is sort-inserted; otherwise, rq will be
* appended to the dispatch queue. To be used by specific elevators.
*/
-void elv_dispatch_insert(request_queue_t *q, struct request *rq, int sort)
+void elv_dispatch_sort(request_queue_t *q, struct request *rq)
{
sector_t boundary;
unsigned max_back;
struct list_head *entry;
- if (!sort) {
- /* Specific elevator is performing sort. Step away. */
- q->last_sector = rq_last_sector(rq);
- q->boundary_rq = rq;
- list_add_tail(&rq->queuelist, &q->queue_head);
- return;
- }
-
- boundary = q->last_sector;
+ boundary = q->end_sector;
max_back = q->max_back_kb * 2;
boundary = boundary > max_back ? boundary - max_back : 0;
-
+
list_for_each_prev(entry, &q->queue_head) {
struct request *pos = list_entry_rq(entry);
@@ -343,10 +334,10 @@
where = ELEVATOR_INSERT_BACK;
/*
- * this request is scheduling boundary, update last_sector
+ * this request is scheduling boundary, update end_sector
*/
if (blk_fs_request(rq)) {
- q->last_sector = rq_last_sector(rq);
+ q->end_sector = rq_end_sector(rq);
q->boundary_rq = rq;
}
}
@@ -479,7 +470,7 @@
q->last_merge = NULL;
if (!q->boundary_rq || q->boundary_rq == rq) {
- q->last_sector = rq_last_sector(rq);
+ q->end_sector = rq_end_sector(rq);
q->boundary_rq = NULL;
}
@@ -802,7 +793,7 @@
return len;
}
-EXPORT_SYMBOL(elv_dispatch_insert);
+EXPORT_SYMBOL(elv_dispatch_sort);
EXPORT_SYMBOL(elv_add_request);
EXPORT_SYMBOL(__elv_add_request);
EXPORT_SYMBOL(elv_requeue_request);
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 2c7b915..a2e496f 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -337,7 +337,7 @@
/*
* Dispatch queue sorting
*/
- sector_t last_sector;
+ sector_t end_sector;
struct request *boundary_rq;
unsigned int max_back_kb;
@@ -625,6 +625,17 @@
}
/*
+ * This should be in elevator.h, but that requires pulling in rq and q
+ */
+static inline void elv_dispatch_add_tail(struct request_queue *q,
+ struct request *rq)
+{
+ q->end_sector = rq_end_sector(rq);
+ q->boundary_rq = rq;
+ list_add_tail(&rq->queuelist, &q->queue_head);
+}
+
+/*
* Access functions for manipulating queue properties
*/
extern request_queue_t *blk_init_queue_node(request_fn_proc *rfn,
diff --git a/include/linux/elevator.h b/include/linux/elevator.h
index 76f4f69..f9b5ec3 100644
--- a/include/linux/elevator.h
+++ b/include/linux/elevator.h
@@ -79,7 +79,7 @@
/*
* block elevator interface
*/
-extern void elv_dispatch_insert(request_queue_t *, struct request *, int);
+extern void elv_dispatch_sort(request_queue_t *, struct request *);
extern void elv_add_request(request_queue_t *, struct request *, int, int);
extern void __elv_add_request(request_queue_t *, struct request *, int, int);
extern int elv_merge(request_queue_t *, struct request **, struct bio *);
@@ -140,4 +140,6 @@
ELV_MQUEUE_MUST,
};
+#define rq_end_sector(rq) ((rq)->sector + (rq)->nr_sectors)
+
#endif