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-rw-r--r--block/deadline-iosched.c128
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;
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.