X-Git-Url: http://ftp.safe.ca/?p=safe%2Fjmp%2Flinux-2.6;a=blobdiff_plain;f=block%2Fdeadline-iosched.c;h=b547cbca7b23a55dd9d1f0b444bed07d297fc646;hp=06962d8402a3c55ed4532bd13af4d7142e54de91;hb=dc7a08166f3a5f23e79e839a8a88849bd3397c32;hpb=3db3a445308b3cee9bbbd8baa6d05081c9532da0 diff --git a/block/deadline-iosched.c b/block/deadline-iosched.c index 06962d8..b547cbc 100644 --- a/block/deadline-iosched.c +++ b/block/deadline-iosched.c @@ -1,19 +1,17 @@ /* * Deadline i/o scheduler. * - * Copyright (C) 2002 Jens Axboe + * Copyright (C) 2002 Jens Axboe */ #include #include #include #include #include -#include #include #include #include #include -#include #include /* @@ -25,14 +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 list_entry_hash(ptr) list_entry((ptr), struct deadline_rq, hash) -#define ON_HASH(drq) (drq)->on_hash - struct deadline_data { /* * run time data @@ -43,12 +33,11 @@ struct deadline_data { */ struct rb_root sort_list[2]; struct list_head fifo_list[2]; - + /* * next in sort order. read, write or both are NULL */ - struct deadline_rq *next_drq[2]; - struct list_head *hash; /* request hash */ + struct request *next_rq[2]; unsigned int batching; /* number of sequential requests made */ sector_t last_sector; /* head position */ unsigned int starved; /* times reads have starved writes */ @@ -60,279 +49,96 @@ struct deadline_data { int fifo_batch; int writes_starved; int front_merges; - - mempool_t *drq_pool; }; -/* - * 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; - - /* - * request hash, key is the ending offset (for back merge lookup) - */ - struct list_head hash; - char on_hash; - - /* - * expire fifo - */ - struct list_head fifo; - unsigned long expires; -}; - -static void deadline_move_request(struct deadline_data *dd, struct deadline_rq *drq); - -static kmem_cache_t *drq_pool; +static void deadline_move_request(struct deadline_data *, struct request *); -#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) +static inline struct rb_root * +deadline_rb_root(struct deadline_data *dd, struct request *rq) { - drq->on_hash = 0; - list_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)); - - drq->on_hash = 1; - list_add(&drq->hash, &dd->hash[DL_HASH_FN(rq_hash_key(rq))]); + return &dd->sort_list[rq_data_dir(rq)]; } /* - * move hot entry to front of chain + * get the request after `rq' in sector-sorted order */ -static inline void -deadline_hot_drq_hash(struct deadline_data *dd, struct deadline_rq *drq) +static inline struct request * +deadline_latter_request(struct request *rq) { - struct request *rq = drq->request; - struct list_head *head = &dd->hash[DL_HASH_FN(rq_hash_key(rq))]; + struct rb_node *node = rb_next(&rq->rb_node); - if (ON_HASH(drq) && drq->hash.prev != head) { - list_del(&drq->hash); - list_add(&drq->hash, head); - } -} - -static struct request * -deadline_find_drq_hash(struct deadline_data *dd, sector_t offset) -{ - struct list_head *hash_list = &dd->hash[DL_HASH_FN(offset)]; - struct list_head *entry, *next = hash_list->next; - - while ((entry = next) != hash_list) { - struct deadline_rq *drq = list_entry_hash(entry); - struct request *__rq = drq->request; - - next = entry->next; - - BUG_ON(!ON_HASH(drq)); - - if (!rq_mergeable(__rq)) { - __deadline_del_drq_hash(drq); - continue; - } - - if (rq_hash_key(__rq) == offset) - return __rq; - } + if (node) + return rb_entry_rq(node); return NULL; } -/* - * rb tree support functions - */ -#define RB_EMPTY(root) ((root)->rb_node == NULL) -#define ON_RB(node) (rb_parent(node) != node) -#define RB_CLEAR(node) (rb_set_parent(node, node)) -#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; -} - static void -deadline_add_drq_rb(struct deadline_data *dd, struct deadline_rq *drq) +deadline_add_rq_rb(struct deadline_data *dd, struct request *rq) { - struct deadline_rq *__alias; - - drq->rb_key = rq_rb_key(drq->request); - -retry: - __alias = __deadline_add_drq_rb(dd, drq); - if (!__alias) { - rb_insert_color(&drq->rb_node, DRQ_RB_ROOT(dd, drq)); - return; - } + struct rb_root *root = deadline_rb_root(dd, rq); + struct request *__alias; - deadline_move_request(dd, __alias); - goto retry; + while (unlikely(__alias = elv_rb_add(root, rq))) + deadline_move_request(dd, __alias); } static inline void -deadline_del_drq_rb(struct deadline_data *dd, struct deadline_rq *drq) +deadline_del_rq_rb(struct deadline_data *dd, struct request *rq) { - const int data_dir = rq_data_dir(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); + if (dd->next_rq[data_dir] == rq) + dd->next_rq[data_dir] = deadline_latter_request(rq); - dd->next_drq[data_dir] = NULL; - if (rbnext) - dd->next_drq[data_dir] = rb_entry_drq(rbnext); - } - - BUG_ON(!ON_RB(&drq->rb_node)); - rb_erase(&drq->rb_node, DRQ_RB_ROOT(dd, drq)); - RB_CLEAR(&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; + elv_rb_del(deadline_rb_root(dd, rq), rq); } /* - * 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; - } -} - -/* - * add drq to rbtree and fifo + * add rq to rbtree and fifo */ static void 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(rq); - const int data_dir = rq_data_dir(drq->request); + deadline_add_rq_rb(dd, rq); - deadline_add_drq_rb(dd, drq); /* - * set expire time (only used for reads) and add to fifo list + * set expire time 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); + rq_set_fifo_time(rq, jiffies + dd->fifo_expire[data_dir]); + list_add_tail(&rq->queuelist, &dd->fifo_list[data_dir]); } /* - * 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) +static void deadline_remove_request(struct request_queue *q, struct request *rq) { - struct deadline_rq *drq = RQ_DATA(rq); struct deadline_data *dd = q->elevator->elevator_data; - list_del_init(&drq->fifo); - deadline_del_drq_rb(dd, drq); - deadline_del_drq_hash(drq); + rq_fifo_clear(rq); + deadline_del_rq_rb(dd, rq); } static int -deadline_merge(request_queue_t *q, struct request **req, struct bio *bio) +deadline_merge(struct request_queue *q, struct request **req, struct bio *bio) { struct deadline_data *dd = q->elevator->elevator_data; struct request *__rq; 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) { - 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 != blk_rq_pos(__rq)); if (elv_rq_merge_ok(__rq, bio)) { ret = ELEVATOR_FRONT_MERGE; @@ -343,63 +149,36 @@ 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; } -static void deadline_merged_request(request_queue_t *q, struct request *req) +static void deadline_merged_request(struct request_queue *q, + struct request *req, int type) { struct deadline_data *dd = q->elevator->elevator_data; - 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) { - deadline_del_drq_rb(dd, drq); - deadline_add_drq_rb(dd, drq); + if (type == ELEVATOR_FRONT_MERGE) { + elv_rb_del(deadline_rb_root(dd, req), req); + deadline_add_rq_rb(dd, req); } } static void -deadline_merged_requests(request_queue_t *q, struct request *req, +deadline_merged_requests(struct request_queue *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); - - /* - * 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); - } - /* - * if dnext expires before drq, assign its expire time to drq - * and move into dnext position (dnext will be deleted) in fifo + * if next expires before rq, assign its expire time to rq + * and move into next position (next will be deleted) in fifo */ - if (!list_empty(&drq->fifo) && !list_empty(&dnext->fifo)) { - if (time_before(dnext->expires, drq->expires)) { - list_move(&drq->fifo, &dnext->fifo); - drq->expires = dnext->expires; + if (!list_empty(&req->queuelist) && !list_empty(&next->queuelist)) { + if (time_before(rq_fifo_time(next), rq_fifo_time(req))) { + list_move(&req->queuelist, &next->queuelist); + rq_set_fifo_time(req, rq_fifo_time(next)); } } @@ -413,52 +192,47 @@ deadline_merged_requests(request_queue_t *q, struct request *req, * move request from sort list to dispatch queue. */ static inline void -deadline_move_to_dispatch(struct deadline_data *dd, struct deadline_rq *drq) +deadline_move_to_dispatch(struct deadline_data *dd, struct request *rq) { - request_queue_t *q = drq->request->q; + struct request_queue *q = rq->q; - deadline_remove_request(q, drq->request); - elv_dispatch_add_tail(q, drq->request); + deadline_remove_request(q, rq); + elv_dispatch_add_tail(q, rq); } /* * move an entry to dispatch queue */ static void -deadline_move_request(struct deadline_data *dd, struct deadline_rq *drq) +deadline_move_request(struct deadline_data *dd, struct request *rq) { - const int data_dir = rq_data_dir(drq->request); - struct rb_node *rbnext = rb_next(&drq->rb_node); + const int data_dir = rq_data_dir(rq); - dd->next_drq[READ] = NULL; - dd->next_drq[WRITE] = NULL; + dd->next_rq[READ] = NULL; + dd->next_rq[WRITE] = NULL; + dd->next_rq[data_dir] = deadline_latter_request(rq); - if (rbnext) - dd->next_drq[data_dir] = rb_entry_drq(rbnext); - - dd->last_sector = drq->request->sector + drq->request->nr_sectors; + dd->last_sector = rq_end_sector(rq); /* * take it off the sort and fifo list, move * to dispatch queue */ - deadline_move_to_dispatch(dd, drq); + deadline_move_to_dispatch(dd, rq); } -#define list_entry_fifo(ptr) list_entry((ptr), struct deadline_rq, fifo) - /* - * deadline_check_fifo returns 0 if there are no expired reads on the fifo, + * deadline_check_fifo returns 0 if there are no expired requests on the fifo, * 1 otherwise. Requires !list_empty(&dd->fifo_list[data_dir]) */ static inline int deadline_check_fifo(struct deadline_data *dd, int ddir) { - struct deadline_rq *drq = list_entry_fifo(dd->fifo_list[ddir].next); + struct request *rq = rq_entry_fifo(dd->fifo_list[ddir].next); /* - * drq is expired! + * rq is expired! */ - if (time_after(jiffies, drq->expires)) + if (time_after(jiffies, rq_fifo_time(rq))) return 1; return 0; @@ -468,33 +242,25 @@ static inline int deadline_check_fifo(struct deadline_data *dd, int ddir) * deadline_dispatch_requests selects the best request according to * read/write expire, fifo_batch, etc */ -static int deadline_dispatch_requests(request_queue_t *q, int force) +static int deadline_dispatch_requests(struct request_queue *q, int force) { struct deadline_data *dd = q->elevator->elevator_data; const int reads = !list_empty(&dd->fifo_list[READ]); const int writes = !list_empty(&dd->fifo_list[WRITE]); - struct deadline_rq *drq; + struct request *rq; int data_dir; /* * batches are currently reads XOR writes */ - if (dd->next_drq[WRITE]) - drq = dd->next_drq[WRITE]; + if (dd->next_rq[WRITE]) + rq = dd->next_rq[WRITE]; else - drq = dd->next_drq[READ]; - - if (drq) { - /* we have a "next request" */ - - if (dd->last_sector != drq->request->sector) - /* end the batch on a non sequential request */ - dd->batching += dd->fifo_batch; - - if (dd->batching < dd->fifo_batch) - /* we are still entitled to batch */ - goto dispatch_request; - } + rq = dd->next_rq[READ]; + + if (rq && dd->batching < dd->fifo_batch) + /* we have a next request are still entitled to batch */ + goto dispatch_request; /* * at this point we are not running a batch. select the appropriate @@ -502,7 +268,7 @@ static int deadline_dispatch_requests(request_queue_t *q, int force) */ if (reads) { - BUG_ON(RB_EMPTY(&dd->sort_list[READ])); + BUG_ON(RB_EMPTY_ROOT(&dd->sort_list[READ])); if (writes && (dd->starved++ >= dd->writes_starved)) goto dispatch_writes; @@ -518,7 +284,7 @@ static int deadline_dispatch_requests(request_queue_t *q, int force) if (writes) { dispatch_writes: - BUG_ON(RB_EMPTY(&dd->sort_list[WRITE])); + BUG_ON(RB_EMPTY_ROOT(&dd->sort_list[WRITE])); dd->starved = 0; @@ -533,38 +299,34 @@ dispatch_find_request: /* * we are not running a batch, find best request for selected data_dir */ - if (deadline_check_fifo(dd, data_dir)) { - /* An expired request exists - satisfy it */ - dd->batching = 0; - drq = list_entry_fifo(dd->fifo_list[data_dir].next); - - } else if (dd->next_drq[data_dir]) { + if (deadline_check_fifo(dd, data_dir) || !dd->next_rq[data_dir]) { /* - * The last req was the same dir and we have a next request in - * sort order. No expired requests so continue on from here. + * A deadline has expired, the last request was in the other + * direction, or we have run out of higher-sectored requests. + * Start again from the request with the earliest expiry time. */ - drq = dd->next_drq[data_dir]; + rq = rq_entry_fifo(dd->fifo_list[data_dir].next); } else { /* - * 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. + * The last req was the same dir and we have a next request in + * sort order. No expired requests so continue on from here. */ - dd->batching = 0; - drq = deadline_find_first_drq(dd, data_dir); + rq = dd->next_rq[data_dir]; } + dd->batching = 0; + dispatch_request: /* - * drq is the selected appropriate request. + * rq is the selected appropriate request. */ dd->batching++; - deadline_move_request(dd, drq); + deadline_move_request(dd, rq); return 1; } -static int deadline_queue_empty(request_queue_t *q) +static int deadline_queue_empty(struct request_queue *q) { struct deadline_data *dd = q->elevator->elevator_data; @@ -572,76 +334,26 @@ static int deadline_queue_empty(request_queue_t *q) && 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) +static void deadline_exit_queue(struct elevator_queue *e) { struct deadline_data *dd = e->elevator_data; BUG_ON(!list_empty(&dd->fifo_list[READ])); BUG_ON(!list_empty(&dd->fifo_list[WRITE])); - mempool_destroy(dd->drq_pool); - kfree(dd->hash); kfree(dd); } /* - * initialize elevator private data (deadline_data), and alloc a drq for - * each request on the free lists + * initialize elevator private data (deadline_data). */ -static int deadline_init_queue(request_queue_t *q, elevator_t *e) +static void *deadline_init_queue(struct request_queue *q) { struct deadline_data *dd; - int i; - - if (!drq_pool) - return -ENOMEM; - dd = kmalloc_node(sizeof(*dd), GFP_KERNEL, q->node); + dd = kmalloc_node(sizeof(*dd), GFP_KERNEL | __GFP_ZERO, q->node); if (!dd) - return -ENOMEM; - memset(dd, 0, sizeof(*dd)); - - dd->hash = kmalloc_node(sizeof(struct list_head)*DL_HASH_ENTRIES, - GFP_KERNEL, q->node); - if (!dd->hash) { - kfree(dd); - return -ENOMEM; - } - - 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 -ENOMEM; - } - - for (i = 0; i < DL_HASH_ENTRIES; i++) - INIT_LIST_HEAD(&dd->hash[i]); + return NULL; INIT_LIST_HEAD(&dd->fifo_list[READ]); INIT_LIST_HEAD(&dd->fifo_list[WRITE]); @@ -652,42 +364,7 @@ static int deadline_init_queue(request_queue_t *q, elevator_t *e) dd->writes_starved = writes_starved; dd->front_merges = 1; dd->fifo_batch = fifo_batch; - e->elevator_data = dd; - return 0; -} - -static void deadline_put_request(request_queue_t *q, struct request *rq) -{ - struct deadline_data *dd = q->elevator->elevator_data; - struct deadline_rq *drq = RQ_DATA(rq); - - mempool_free(drq, dd->drq_pool); - rq->elevator_private = NULL; -} - -static int -deadline_set_request(request_queue_t *q, struct request *rq, struct bio *bio, - gfp_t gfp_mask) -{ - struct deadline_data *dd = q->elevator->elevator_data; - struct deadline_rq *drq; - - drq = mempool_alloc(dd->drq_pool, gfp_mask); - if (drq) { - memset(drq, 0, sizeof(*drq)); - RB_CLEAR(&drq->rb_node); - drq->request = rq; - - INIT_LIST_HEAD(&drq->hash); - drq->on_hash = 0; - - INIT_LIST_HEAD(&drq->fifo); - - rq->elevator_private = drq; - return 0; - } - - return 1; + return dd; } /* @@ -710,7 +387,7 @@ deadline_var_store(int *var, const char *page, size_t count) } #define SHOW_FUNCTION(__FUNC, __VAR, __CONV) \ -static ssize_t __FUNC(elevator_t *e, char *page) \ +static ssize_t __FUNC(struct elevator_queue *e, char *page) \ { \ struct deadline_data *dd = e->elevator_data; \ int __data = __VAR; \ @@ -726,7 +403,7 @@ SHOW_FUNCTION(deadline_fifo_batch_show, dd->fifo_batch, 0); #undef SHOW_FUNCTION #define STORE_FUNCTION(__FUNC, __PTR, MIN, MAX, __CONV) \ -static ssize_t __FUNC(elevator_t *e, const char *page, size_t count) \ +static ssize_t __FUNC(struct elevator_queue *e, const char *page, size_t count) \ { \ struct deadline_data *dd = e->elevator_data; \ int __data; \ @@ -769,10 +446,8 @@ static struct elevator_type iosched_deadline = { .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_set_req_fn = deadline_set_request, - .elevator_put_req_fn = deadline_put_request, + .elevator_former_req_fn = elv_rb_former_request, + .elevator_latter_req_fn = elv_rb_latter_request, .elevator_init_fn = deadline_init_queue, .elevator_exit_fn = deadline_exit_queue, }, @@ -784,24 +459,13 @@ static struct elevator_type iosched_deadline = { static int __init deadline_init(void) { - int ret; - - drq_pool = kmem_cache_create("deadline_drq", sizeof(struct deadline_rq), - 0, 0, NULL, NULL); + elv_register(&iosched_deadline); - if (!drq_pool) - return -ENOMEM; - - ret = elv_register(&iosched_deadline); - if (ret) - kmem_cache_destroy(drq_pool); - - return ret; + return 0; } static void __exit deadline_exit(void) { - kmem_cache_destroy(drq_pool); elv_unregister(&iosched_deadline); }