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authorJens Axboe <axboe@suse.de>2005-10-20 10:37:00 -0400
committerJens Axboe <axboe@nelson.home.kernel.dk>2005-10-28 02:44:37 -0400
commit1b47f531e244e339b648dfff071c086f936e49e1 (patch)
tree4ecbec3d9ade19e01a47c562772db550daadcef2 /drivers/block/elevator.c
parent8922e16cf6269e668123acb1ae1fdc62b7a3a4fc (diff)
[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>
Diffstat (limited to 'drivers/block/elevator.c')
-rw-r--r--drivers/block/elevator.c33
1 files changed, 12 insertions, 21 deletions
diff --git a/drivers/block/elevator.c b/drivers/block/elevator.c
index a27555908d35..237e43d760c8 100644
--- a/drivers/block/elevator.c
+++ b/drivers/block/elevator.c
@@ -40,11 +40,6 @@
40static DEFINE_SPINLOCK(elv_list_lock); 40static DEFINE_SPINLOCK(elv_list_lock);
41static LIST_HEAD(elv_list); 41static LIST_HEAD(elv_list);
42 42
43static inline sector_t rq_last_sector(struct request *rq)
44{
45 return rq->sector + rq->nr_sectors;
46}
47
48/* 43/*
49 * can we safely merge with this request? 44 * can we safely merge with this request?
50 */ 45 */
@@ -148,7 +143,7 @@ static int elevator_attach(request_queue_t *q, struct elevator_type *e,
148 INIT_LIST_HEAD(&q->queue_head); 143 INIT_LIST_HEAD(&q->queue_head);
149 q->last_merge = NULL; 144 q->last_merge = NULL;
150 q->elevator = eq; 145 q->elevator = eq;
151 q->last_sector = 0; 146 q->end_sector = 0;
152 q->boundary_rq = NULL; 147 q->boundary_rq = NULL;
153 q->max_back_kb = 0; 148 q->max_back_kb = 0;
154 149
@@ -233,29 +228,25 @@ void elevator_exit(elevator_t *e)
233 kfree(e); 228 kfree(e);
234} 229}
235 230
231void elv_dispatch_insert_tail(request_queue_t *q, struct request *rq)
232{
233}
234
236/* 235/*
237 * Insert rq into dispatch queue of q. Queue lock must be held on 236 * Insert rq into dispatch queue of q. Queue lock must be held on
238 * entry. If sort != 0, rq is sort-inserted; otherwise, rq will be 237 * entry. If sort != 0, rq is sort-inserted; otherwise, rq will be
239 * appended to the dispatch queue. To be used by specific elevators. 238 * appended to the dispatch queue. To be used by specific elevators.
240 */ 239 */
241void elv_dispatch_insert(request_queue_t *q, struct request *rq, int sort) 240void elv_dispatch_sort(request_queue_t *q, struct request *rq)
242{ 241{
243 sector_t boundary; 242 sector_t boundary;
244 unsigned max_back; 243 unsigned max_back;
245 struct list_head *entry; 244 struct list_head *entry;
246 245
247 if (!sort) { 246 boundary = q->end_sector;
248 /* Specific elevator is performing sort. Step away. */
249 q->last_sector = rq_last_sector(rq);
250 q->boundary_rq = rq;
251 list_add_tail(&rq->queuelist, &q->queue_head);
252 return;
253 }
254
255 boundary = q->last_sector;
256 max_back = q->max_back_kb * 2; 247 max_back = q->max_back_kb * 2;
257 boundary = boundary > max_back ? boundary - max_back : 0; 248 boundary = boundary > max_back ? boundary - max_back : 0;
258 249
259 list_for_each_prev(entry, &q->queue_head) { 250 list_for_each_prev(entry, &q->queue_head) {
260 struct request *pos = list_entry_rq(entry); 251 struct request *pos = list_entry_rq(entry);
261 252
@@ -343,10 +334,10 @@ void __elv_add_request(request_queue_t *q, struct request *rq, int where,
343 where = ELEVATOR_INSERT_BACK; 334 where = ELEVATOR_INSERT_BACK;
344 335
345 /* 336 /*
346 * this request is scheduling boundary, update last_sector 337 * this request is scheduling boundary, update end_sector
347 */ 338 */
348 if (blk_fs_request(rq)) { 339 if (blk_fs_request(rq)) {
349 q->last_sector = rq_last_sector(rq); 340 q->end_sector = rq_end_sector(rq);
350 q->boundary_rq = rq; 341 q->boundary_rq = rq;
351 } 342 }
352 } 343 }
@@ -479,7 +470,7 @@ struct request *elv_next_request(request_queue_t *q)
479 q->last_merge = NULL; 470 q->last_merge = NULL;
480 471
481 if (!q->boundary_rq || q->boundary_rq == rq) { 472 if (!q->boundary_rq || q->boundary_rq == rq) {
482 q->last_sector = rq_last_sector(rq); 473 q->end_sector = rq_end_sector(rq);
483 q->boundary_rq = NULL; 474 q->boundary_rq = NULL;
484 } 475 }
485 476
@@ -802,7 +793,7 @@ ssize_t elv_iosched_show(request_queue_t *q, char *name)
802 return len; 793 return len;
803} 794}
804 795
805EXPORT_SYMBOL(elv_dispatch_insert); 796EXPORT_SYMBOL(elv_dispatch_sort);
806EXPORT_SYMBOL(elv_add_request); 797EXPORT_SYMBOL(elv_add_request);
807EXPORT_SYMBOL(__elv_add_request); 798EXPORT_SYMBOL(__elv_add_request);
808EXPORT_SYMBOL(elv_requeue_request); 799EXPORT_SYMBOL(elv_requeue_request);