1 files changed, 2 insertions, 126 deletions

diff --git a/block/deadline-iosched.c b/block/deadline-iosched.c
index c7ca9f0b6498..b66e820f544d 100644
--- a/block/deadline-iosched.c
+++ b/block/deadline-iosched.c
@@ -12,7 +12,6 @@
 #include <linux/slab.h>
 #include <linux/init.h>
 #include <linux/compiler.h>
-#include <linux/hash.h>
 #include <linux/rbtree.h>
 
 /*
@@ -24,13 +23,6 @@ static const int writes_starved = 2;    /* max times reads can starve a write */
 static const int fifo_batch = 16;       /* # of sequential requests treated as one
                                      by the above parameters. For throughput. */
 
-static const int deadline_hash_shift = 5;
-#define DL_HASH_BLOCK(sec)      ((sec) >> 3)
-#define DL_HASH_FN(sec)         (hash_long(DL_HASH_BLOCK((sec)), deadline_hash_shift))
-#define DL_HASH_ENTRIES         (1 << deadline_hash_shift)
-#define rq_hash_key(rq)         ((rq)->sector + (rq)->nr_sectors)
-#define ON_HASH(drq)            (!hlist_unhashed(&(drq)->hash))
-
 struct deadline_data {
         /*
          * run time data
@@ -46,7 +38,6 @@ struct deadline_data {
          * next in sort order. read, write or both are NULL
          */
         struct deadline_rq *next_drq[2];
-        struct hlist_head *hash;        /* request hash */
         unsigned int batching;          /* number of sequential requests made */
         sector_t last_sector;           /* head position */
         unsigned int starved;           /* times reads have starved writes */
@@ -75,11 +66,6 @@ struct deadline_rq {
         struct request *request;
 
         /*
-         * request hash, key is the ending offset (for back merge lookup)
-         */
-        struct hlist_node hash;
-
-        /*
          * expire fifo
          */
         struct list_head fifo;
@@ -93,69 +79,6 @@ static kmem_cache_t *drq_pool;
 #define RQ_DATA(rq)     ((struct deadline_rq *) (rq)->elevator_private)
 
 /*
- * the back merge hash support functions
- */
-static inline void __deadline_del_drq_hash(struct deadline_rq *drq)
-{
-        hlist_del_init(&drq->hash);
-}
-
-static inline void deadline_del_drq_hash(struct deadline_rq *drq)
-{
-        if (ON_HASH(drq))
-                __deadline_del_drq_hash(drq);
-}
-
-static inline void
-deadline_add_drq_hash(struct deadline_data *dd, struct deadline_rq *drq)
-{
-        struct request *rq = drq->request;
-
-        BUG_ON(ON_HASH(drq));
-
-        hlist_add_head(&drq->hash, &dd->hash[DL_HASH_FN(rq_hash_key(rq))]);
-}
-
-/*
- * move hot entry to front of chain
- */
-static inline void
-deadline_hot_drq_hash(struct deadline_data *dd, struct deadline_rq *drq)
-{
-        struct request *rq = drq->request;
-        struct hlist_head *head = &dd->hash[DL_HASH_FN(rq_hash_key(rq))];
-
-        if (ON_HASH(drq) && &drq->hash != head->first) {
-                hlist_del(&drq->hash);
-                hlist_add_head(&drq->hash, head);
-        }
-}
-
-static struct request *
-deadline_find_drq_hash(struct deadline_data *dd, sector_t offset)
-{
-        struct hlist_head *hash_list = &dd->hash[DL_HASH_FN(offset)];
-        struct hlist_node *entry, *next;
-        struct deadline_rq *drq;
-
-        hlist_for_each_entry_safe(drq, entry, next, hash_list, hash) {
-                struct request *__rq = drq->request;
-
-                BUG_ON(!ON_HASH(drq));
-
-                if (!rq_mergeable(__rq)) {
-                        __deadline_del_drq_hash(drq);
-                        continue;
-                }
-
-                if (rq_hash_key(__rq) == offset)
-                        return __rq;
-        }
-
-        return NULL;
-}
-
-/*
  * rb tree support functions
  */
 #define rb_entry_drq(node)      rb_entry((node), struct deadline_rq, rb_node)
@@ -267,22 +190,19 @@ deadline_add_request(struct request_queue *q, struct request *rq)
 {
         struct deadline_data *dd = q->elevator->elevator_data;
         struct deadline_rq *drq = RQ_DATA(rq);
-
         const int data_dir = rq_data_dir(drq->request);
 
         deadline_add_drq_rb(dd, drq);
+
         /*
          * set expire time (only used for reads) and add to fifo list
          */
         drq->expires = jiffies + dd->fifo_expire[data_dir];
         list_add_tail(&drq->fifo, &dd->fifo_list[data_dir]);
-
-        if (rq_mergeable(rq))
-                deadline_add_drq_hash(dd, drq);
 }
 
 /*
- * remove rq from rbtree, fifo, and hash
+ * remove rq from rbtree and fifo.
  */
 static void deadline_remove_request(request_queue_t *q, struct request *rq)
 {
@@ -291,7 +211,6 @@ static void deadline_remove_request(request_queue_t *q, struct request *rq)
 
         list_del_init(&drq->fifo);
         deadline_del_drq_rb(dd, drq);
-        deadline_del_drq_hash(drq);
 }
 
 static int
@@ -302,19 +221,6 @@ deadline_merge(request_queue_t *q, struct request **req, struct bio *bio)
         int ret;
 
         /*
-         * see if the merge hash can satisfy a back merge
-         */
-        __rq = deadline_find_drq_hash(dd, bio->bi_sector);
-        if (__rq) {
-                BUG_ON(__rq->sector + __rq->nr_sectors != bio->bi_sector);
-
-                if (elv_rq_merge_ok(__rq, bio)) {
-                        ret = ELEVATOR_BACK_MERGE;
-                        goto out;
-                }
-        }
-
-        /*
          * check for front merge
          */
         if (dd->front_merges) {
@@ -333,8 +239,6 @@ deadline_merge(request_queue_t *q, struct request **req, struct bio *bio)
 
         return ELEVATOR_NO_MERGE;
 out:
-        if (ret)
-                deadline_hot_drq_hash(dd, RQ_DATA(__rq));
         *req = __rq;
         return ret;
 }
@@ -345,12 +249,6 @@ static void deadline_merged_request(request_queue_t *q, struct request *req)
         struct deadline_rq *drq = RQ_DATA(req);
 
         /*
-         * hash always needs to be repositioned, key is end sector
-         */
-        deadline_del_drq_hash(drq);
-        deadline_add_drq_hash(dd, drq);
-
-        /*
          * if the merge was a front merge, we need to reposition request
          */
         if (rq_rb_key(req) != drq->rb_key) {
@@ -370,13 +268,6 @@ deadline_merged_requests(request_queue_t *q, struct request *req,
         BUG_ON(!drq);
         BUG_ON(!dnext);
 
-        /*
-         * reposition drq (this is the merged request) in hash, and in rbtree
-         * in case of a front merge
-         */
-        deadline_del_drq_hash(drq);
-        deadline_add_drq_hash(dd, drq);
-
         if (rq_rb_key(req) != drq->rb_key) {
                 deadline_del_drq_rb(dd, drq);
                 deadline_add_drq_rb(dd, drq);
@@ -594,7 +485,6 @@ static void deadline_exit_queue(elevator_t *e)
         BUG_ON(!list_empty(&dd->fifo_list[WRITE]));
 
         mempool_destroy(dd->drq_pool);
-        kfree(dd->hash);
         kfree(dd);
 }
 
@@ -605,7 +495,6 @@ static void deadline_exit_queue(elevator_t *e)
 static void *deadline_init_queue(request_queue_t *q, elevator_t *e)
 {
         struct deadline_data *dd;
-        int i;
 
         if (!drq_pool)
                 return NULL;
@@ -615,24 +504,13 @@ static void *deadline_init_queue(request_queue_t *q, elevator_t *e)
                 return NULL;
         memset(dd, 0, sizeof(*dd));
 
-        dd->hash = kmalloc_node(sizeof(struct hlist_head)*DL_HASH_ENTRIES,
-                                GFP_KERNEL, q->node);
-        if (!dd->hash) {
-                kfree(dd);
-                return NULL;
-        }
-
         dd->drq_pool = mempool_create_node(BLKDEV_MIN_RQ, mempool_alloc_slab,
                                         mempool_free_slab, drq_pool, q->node);
         if (!dd->drq_pool) {
-                kfree(dd->hash);
                 kfree(dd);
                 return NULL;
         }
 
-        for (i = 0; i < DL_HASH_ENTRIES; i++)
-                INIT_HLIST_HEAD(&dd->hash[i]);
-
         INIT_LIST_HEAD(&dd->fifo_list[READ]);
         INIT_LIST_HEAD(&dd->fifo_list[WRITE]);
         dd->sort_list[READ] = RB_ROOT;
@@ -667,8 +545,6 @@ deadline_set_request(request_queue_t *q, struct request *rq, struct bio *bio,
                 RB_CLEAR_NODE(&drq->rb_node);
                 drq->request = rq;
 
-                INIT_HLIST_NODE(&drq->hash);
-
                 INIT_LIST_HEAD(&drq->fifo);
 
                 rq->elevator_private = drq;