X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=block%2Felevator.c;h=1975b619c86d4e7f4212116c7fd3dd11b2a090eb;hb=ff2c3de305e2d06ae556e1a382ed75c5dd8f9dda;hp=ff60177a3bab2d47a918b3027a3b9ba2020d7e78;hpb=58eea927d2de43dc6f03d1ba2c46e55854b31540;p=safe%2Fjmp%2Flinux-2.6 diff --git a/block/elevator.c b/block/elevator.c index ff60177..1975b61 100644 --- a/block/elevator.c +++ b/block/elevator.c @@ -33,17 +33,16 @@ #include #include #include -#include #include #include +#include + #include "blk.h" static DEFINE_SPINLOCK(elv_list_lock); static LIST_HEAD(elv_list); -DEFINE_TRACE(block_rq_abort); - /* * Merge hash stuff. */ @@ -52,11 +51,7 @@ static const int elv_hash_shift = 6; #define ELV_HASH_FN(sec) \ (hash_long(ELV_HASH_BLOCK((sec)), elv_hash_shift)) #define ELV_HASH_ENTRIES (1 << elv_hash_shift) -#define rq_hash_key(rq) ((rq)->sector + (rq)->nr_sectors) -#define ELV_ON_HASH(rq) (!hlist_unhashed(&(rq)->hash)) - -DEFINE_TRACE(block_rq_insert); -DEFINE_TRACE(block_rq_issue); +#define rq_hash_key(rq) (blk_rq_pos(rq) + blk_rq_sectors(rq)) /* * Query io scheduler to see if the current process issuing bio may be @@ -65,7 +60,7 @@ DEFINE_TRACE(block_rq_issue); static int elv_iosched_allow_merge(struct request *rq, struct bio *bio) { struct request_queue *q = rq->q; - elevator_t *e = q->elevator; + struct elevator_queue *e = q->elevator; if (e->ops->elevator_allow_merge_fn) return e->ops->elevator_allow_merge_fn(q, rq, bio); @@ -84,7 +79,8 @@ int elv_rq_merge_ok(struct request *rq, struct bio *bio) /* * Don't merge file system requests and discard requests */ - if (bio_discard(bio) != bio_discard(rq->bio)) + if (bio_rw_flagged(bio, BIO_RW_DISCARD) != + bio_rw_flagged(rq->bio, BIO_RW_DISCARD)) return 0; /* @@ -120,9 +116,9 @@ static inline int elv_try_merge(struct request *__rq, struct bio *bio) * we can merge and sequence is ok, check if it's possible */ if (elv_rq_merge_ok(__rq, bio)) { - if (__rq->sector + __rq->nr_sectors == bio->bi_sector) + if (blk_rq_pos(__rq) + blk_rq_sectors(__rq) == bio->bi_sector) ret = ELEVATOR_BACK_MERGE; - else if (__rq->sector - bio_sectors(bio) == bio->bi_sector) + else if (blk_rq_pos(__rq) - bio_sectors(bio) == bio->bi_sector) ret = ELEVATOR_FRONT_MERGE; } @@ -208,13 +204,13 @@ __setup("elevator=", elevator_setup); static struct kobj_type elv_ktype; -static elevator_t *elevator_alloc(struct request_queue *q, +static struct elevator_queue *elevator_alloc(struct request_queue *q, struct elevator_type *e) { - elevator_t *eq; + struct elevator_queue *eq; int i; - eq = kmalloc_node(sizeof(elevator_t), GFP_KERNEL | __GFP_ZERO, q->node); + eq = kmalloc_node(sizeof(*eq), GFP_KERNEL | __GFP_ZERO, q->node); if (unlikely(!eq)) goto err; @@ -240,8 +236,9 @@ err: static void elevator_release(struct kobject *kobj) { - elevator_t *e = container_of(kobj, elevator_t, kobj); + struct elevator_queue *e; + e = container_of(kobj, struct elevator_queue, kobj); elevator_put(e->elevator_type); kfree(e->hash); kfree(e); @@ -297,7 +294,7 @@ int elevator_init(struct request_queue *q, char *name) } EXPORT_SYMBOL(elevator_init); -void elevator_exit(elevator_t *e) +void elevator_exit(struct elevator_queue *e) { mutex_lock(&e->sysfs_lock); if (e->ops->elevator_exit_fn) @@ -309,22 +306,6 @@ void elevator_exit(elevator_t *e) } EXPORT_SYMBOL(elevator_exit); -static void elv_activate_rq(struct request_queue *q, struct request *rq) -{ - elevator_t *e = q->elevator; - - if (e->ops->elevator_activate_req_fn) - e->ops->elevator_activate_req_fn(q, rq); -} - -static void elv_deactivate_rq(struct request_queue *q, struct request *rq) -{ - elevator_t *e = q->elevator; - - if (e->ops->elevator_deactivate_req_fn) - e->ops->elevator_deactivate_req_fn(q, rq); -} - static inline void __elv_rqhash_del(struct request *rq) { hlist_del_init(&rq->hash); @@ -338,7 +319,7 @@ static void elv_rqhash_del(struct request_queue *q, struct request *rq) static void elv_rqhash_add(struct request_queue *q, struct request *rq) { - elevator_t *e = q->elevator; + struct elevator_queue *e = q->elevator; BUG_ON(ELV_ON_HASH(rq)); hlist_add_head(&rq->hash, &e->hash[ELV_HASH_FN(rq_hash_key(rq))]); @@ -352,7 +333,7 @@ static void elv_rqhash_reposition(struct request_queue *q, struct request *rq) static struct request *elv_rqhash_find(struct request_queue *q, sector_t offset) { - elevator_t *e = q->elevator; + struct elevator_queue *e = q->elevator; struct hlist_head *hash_list = &e->hash[ELV_HASH_FN(offset)]; struct hlist_node *entry, *next; struct request *rq; @@ -386,9 +367,9 @@ struct request *elv_rb_add(struct rb_root *root, struct request *rq) parent = *p; __rq = rb_entry(parent, struct request, rb_node); - if (rq->sector < __rq->sector) + if (blk_rq_pos(rq) < blk_rq_pos(__rq)) p = &(*p)->rb_left; - else if (rq->sector > __rq->sector) + else if (blk_rq_pos(rq) > blk_rq_pos(__rq)) p = &(*p)->rb_right; else return __rq; @@ -416,9 +397,9 @@ struct request *elv_rb_find(struct rb_root *root, sector_t sector) while (n) { rq = rb_entry(n, struct request, rb_node); - if (sector < rq->sector) + if (sector < blk_rq_pos(rq)) n = n->rb_left; - else if (sector > rq->sector) + else if (sector > blk_rq_pos(rq)) n = n->rb_right; else return rq; @@ -457,14 +438,14 @@ void elv_dispatch_sort(struct request_queue *q, struct request *rq) break; if (pos->cmd_flags & stop_flags) break; - if (rq->sector >= boundary) { - if (pos->sector < boundary) + if (blk_rq_pos(rq) >= boundary) { + if (blk_rq_pos(pos) < boundary) continue; } else { - if (pos->sector >= boundary) + if (blk_rq_pos(pos) >= boundary) break; } - if (rq->sector >= pos->sector) + if (blk_rq_pos(rq) >= blk_rq_pos(pos)) break; } @@ -494,7 +475,7 @@ EXPORT_SYMBOL(elv_dispatch_add_tail); int elv_merge(struct request_queue *q, struct request **req, struct bio *bio) { - elevator_t *e = q->elevator; + struct elevator_queue *e = q->elevator; struct request *__rq; int ret; @@ -529,7 +510,7 @@ int elv_merge(struct request_queue *q, struct request **req, struct bio *bio) void elv_merged_request(struct request_queue *q, struct request *rq, int type) { - elevator_t *e = q->elevator; + struct elevator_queue *e = q->elevator; if (e->ops->elevator_merged_fn) e->ops->elevator_merged_fn(q, rq, type); @@ -543,7 +524,7 @@ void elv_merged_request(struct request_queue *q, struct request *rq, int type) void elv_merge_requests(struct request_queue *q, struct request *rq, struct request *next) { - elevator_t *e = q->elevator; + struct elevator_queue *e = q->elevator; if (e->ops->elevator_merge_req_fn) e->ops->elevator_merge_req_fn(q, rq, next); @@ -562,7 +543,7 @@ void elv_requeue_request(struct request_queue *q, struct request *rq) * in_flight count again */ if (blk_account_rq(rq)) { - q->in_flight--; + q->in_flight[rq_is_sync(rq)]--; if (blk_sorted_rq(rq)) elv_deactivate_rq(q, rq); } @@ -572,7 +553,7 @@ void elv_requeue_request(struct request_queue *q, struct request *rq) elv_insert(q, rq, ELEVATOR_INSERT_REQUEUE); } -static void elv_drain_elevator(struct request_queue *q) +void elv_drain_elevator(struct request_queue *q) { static int printed; while (q->elevator->ops->elevator_dispatch_fn(q, 1)) @@ -586,6 +567,34 @@ static void elv_drain_elevator(struct request_queue *q) } } +/* + * Call with queue lock held, interrupts disabled + */ +void elv_quiesce_start(struct request_queue *q) +{ + if (!q->elevator) + return; + + queue_flag_set(QUEUE_FLAG_ELVSWITCH, q); + + /* + * make sure we don't have any requests in flight + */ + elv_drain_elevator(q); + while (q->rq.elvpriv) { + __blk_run_queue(q); + spin_unlock_irq(q->queue_lock); + msleep(10); + spin_lock_irq(q->queue_lock); + elv_drain_elevator(q); + } +} + +void elv_quiesce_end(struct request_queue *q) +{ + queue_flag_clear(QUEUE_FLAG_ELVSWITCH, q); +} + void elv_insert(struct request_queue *q, struct request *rq, int where) { struct list_head *pos; @@ -617,8 +626,7 @@ void elv_insert(struct request_queue *q, struct request *rq, int where) * with anything. There's no point in delaying queue * processing. */ - blk_remove_plug(q); - blk_start_queueing(q); + __blk_run_queue(q); break; case ELEVATOR_INSERT_SORT: @@ -676,8 +684,8 @@ void elv_insert(struct request_queue *q, struct request *rq, int where) } if (unplug_it && blk_queue_plugged(q)) { - int nrq = q->rq.count[READ] + q->rq.count[WRITE] - - q->in_flight; + int nrq = q->rq.count[BLK_RW_SYNC] + q->rq.count[BLK_RW_ASYNC] + - queue_in_flight(q); if (nrq >= q->unplug_thresh) __generic_unplug_device(q); @@ -733,120 +741,9 @@ void elv_add_request(struct request_queue *q, struct request *rq, int where, } EXPORT_SYMBOL(elv_add_request); -static inline struct request *__elv_next_request(struct request_queue *q) -{ - struct request *rq; - - while (1) { - while (!list_empty(&q->queue_head)) { - rq = list_entry_rq(q->queue_head.next); - if (blk_do_ordered(q, &rq)) - return rq; - } - - if (!q->elevator->ops->elevator_dispatch_fn(q, 0)) - return NULL; - } -} - -struct request *elv_next_request(struct request_queue *q) -{ - struct request *rq; - int ret; - - while ((rq = __elv_next_request(q)) != NULL) { - if (!(rq->cmd_flags & REQ_STARTED)) { - /* - * This is the first time the device driver - * sees this request (possibly after - * requeueing). Notify IO scheduler. - */ - if (blk_sorted_rq(rq)) - elv_activate_rq(q, rq); - - /* - * just mark as started even if we don't start - * it, a request that has been delayed should - * not be passed by new incoming requests - */ - rq->cmd_flags |= REQ_STARTED; - trace_block_rq_issue(q, rq); - } - - if (!q->boundary_rq || q->boundary_rq == rq) { - q->end_sector = rq_end_sector(rq); - q->boundary_rq = NULL; - } - - if (rq->cmd_flags & REQ_DONTPREP) - break; - - if (q->dma_drain_size && rq->data_len) { - /* - * make sure space for the drain appears we - * know we can do this because max_hw_segments - * has been adjusted to be one fewer than the - * device can handle - */ - rq->nr_phys_segments++; - } - - if (!q->prep_rq_fn) - break; - - ret = q->prep_rq_fn(q, rq); - if (ret == BLKPREP_OK) { - break; - } else if (ret == BLKPREP_DEFER) { - /* - * the request may have been (partially) prepped. - * we need to keep this request in the front to - * avoid resource deadlock. REQ_STARTED will - * prevent other fs requests from passing this one. - */ - if (q->dma_drain_size && rq->data_len && - !(rq->cmd_flags & REQ_DONTPREP)) { - /* - * remove the space for the drain we added - * so that we don't add it again - */ - --rq->nr_phys_segments; - } - - rq = NULL; - break; - } else if (ret == BLKPREP_KILL) { - rq->cmd_flags |= REQ_QUIET; - __blk_end_request(rq, -EIO, blk_rq_bytes(rq)); - } else { - printk(KERN_ERR "%s: bad return=%d\n", __func__, ret); - break; - } - } - - return rq; -} -EXPORT_SYMBOL(elv_next_request); - -void elv_dequeue_request(struct request_queue *q, struct request *rq) -{ - BUG_ON(list_empty(&rq->queuelist)); - BUG_ON(ELV_ON_HASH(rq)); - - list_del_init(&rq->queuelist); - - /* - * the time frame between a request being removed from the lists - * and to it is freed is accounted as io that is in progress at - * the driver side. - */ - if (blk_account_rq(rq)) - q->in_flight++; -} - int elv_queue_empty(struct request_queue *q) { - elevator_t *e = q->elevator; + struct elevator_queue *e = q->elevator; if (!list_empty(&q->queue_head)) return 0; @@ -860,7 +757,7 @@ EXPORT_SYMBOL(elv_queue_empty); struct request *elv_latter_request(struct request_queue *q, struct request *rq) { - elevator_t *e = q->elevator; + struct elevator_queue *e = q->elevator; if (e->ops->elevator_latter_req_fn) return e->ops->elevator_latter_req_fn(q, rq); @@ -869,7 +766,7 @@ struct request *elv_latter_request(struct request_queue *q, struct request *rq) struct request *elv_former_request(struct request_queue *q, struct request *rq) { - elevator_t *e = q->elevator; + struct elevator_queue *e = q->elevator; if (e->ops->elevator_former_req_fn) return e->ops->elevator_former_req_fn(q, rq); @@ -878,7 +775,7 @@ struct request *elv_former_request(struct request_queue *q, struct request *rq) int elv_set_request(struct request_queue *q, struct request *rq, gfp_t gfp_mask) { - elevator_t *e = q->elevator; + struct elevator_queue *e = q->elevator; if (e->ops->elevator_set_req_fn) return e->ops->elevator_set_req_fn(q, rq, gfp_mask); @@ -889,7 +786,7 @@ int elv_set_request(struct request_queue *q, struct request *rq, gfp_t gfp_mask) void elv_put_request(struct request_queue *q, struct request *rq) { - elevator_t *e = q->elevator; + struct elevator_queue *e = q->elevator; if (e->ops->elevator_put_req_fn) e->ops->elevator_put_req_fn(rq); @@ -897,7 +794,7 @@ void elv_put_request(struct request_queue *q, struct request *rq) int elv_may_queue(struct request_queue *q, int rw) { - elevator_t *e = q->elevator; + struct elevator_queue *e = q->elevator; if (e->ops->elevator_may_queue_fn) return e->ops->elevator_may_queue_fn(q, rw); @@ -913,20 +810,25 @@ void elv_abort_queue(struct request_queue *q) rq = list_entry_rq(q->queue_head.next); rq->cmd_flags |= REQ_QUIET; trace_block_rq_abort(q, rq); - __blk_end_request(rq, -EIO, blk_rq_bytes(rq)); + /* + * Mark this request as started so we don't trigger + * any debug logic in the end I/O path. + */ + blk_start_request(rq); + __blk_end_request_all(rq, -EIO); } } EXPORT_SYMBOL(elv_abort_queue); void elv_completed_request(struct request_queue *q, struct request *rq) { - elevator_t *e = q->elevator; + struct elevator_queue *e = q->elevator; /* * request is released from the driver, io must be done */ if (blk_account_rq(rq)) { - q->in_flight--; + q->in_flight[rq_is_sync(rq)]--; if (blk_sorted_rq(rq) && e->ops->elevator_completed_req_fn) e->ops->elevator_completed_req_fn(q, rq); } @@ -941,11 +843,11 @@ void elv_completed_request(struct request_queue *q, struct request *rq) if (!list_empty(&q->queue_head)) next = list_entry_rq(q->queue_head.next); - if (!q->in_flight && + if (!queue_in_flight(q) && blk_ordered_cur_seq(q) == QUEUE_ORDSEQ_DRAIN && (!next || blk_ordered_req_seq(next) > QUEUE_ORDSEQ_DRAIN)) { blk_ordered_complete_seq(q, QUEUE_ORDSEQ_DRAIN, 0); - blk_start_queueing(q); + __blk_run_queue(q); } } } @@ -955,13 +857,14 @@ void elv_completed_request(struct request_queue *q, struct request *rq) static ssize_t elv_attr_show(struct kobject *kobj, struct attribute *attr, char *page) { - elevator_t *e = container_of(kobj, elevator_t, kobj); struct elv_fs_entry *entry = to_elv(attr); + struct elevator_queue *e; ssize_t error; if (!entry->show) return -EIO; + e = container_of(kobj, struct elevator_queue, kobj); mutex_lock(&e->sysfs_lock); error = e->ops ? entry->show(e, page) : -ENOENT; mutex_unlock(&e->sysfs_lock); @@ -972,13 +875,14 @@ static ssize_t elv_attr_store(struct kobject *kobj, struct attribute *attr, const char *page, size_t length) { - elevator_t *e = container_of(kobj, elevator_t, kobj); struct elv_fs_entry *entry = to_elv(attr); + struct elevator_queue *e; ssize_t error; if (!entry->store) return -EIO; + e = container_of(kobj, struct elevator_queue, kobj); mutex_lock(&e->sysfs_lock); error = e->ops ? entry->store(e, page, length) : -ENOENT; mutex_unlock(&e->sysfs_lock); @@ -997,7 +901,7 @@ static struct kobj_type elv_ktype = { int elv_register_queue(struct request_queue *q) { - elevator_t *e = q->elevator; + struct elevator_queue *e = q->elevator; int error; error = kobject_add(&e->kobj, &q->kobj, "%s", "iosched"); @@ -1015,7 +919,7 @@ int elv_register_queue(struct request_queue *q) return error; } -static void __elv_unregister_queue(elevator_t *e) +static void __elv_unregister_queue(struct elevator_queue *e) { kobject_uevent(&e->kobj, KOBJ_REMOVE); kobject_del(&e->kobj); @@ -1078,7 +982,7 @@ EXPORT_SYMBOL_GPL(elv_unregister); */ static int elevator_switch(struct request_queue *q, struct elevator_type *new_e) { - elevator_t *old_elevator, *e; + struct elevator_queue *old_elevator, *e; void *data; /* @@ -1098,18 +1002,7 @@ static int elevator_switch(struct request_queue *q, struct elevator_type *new_e) * Turn on BYPASS and drain all requests w/ elevator private data */ spin_lock_irq(q->queue_lock); - - queue_flag_set(QUEUE_FLAG_ELVSWITCH, q); - - elv_drain_elevator(q); - - while (q->rq.elvpriv) { - blk_start_queueing(q); - spin_unlock_irq(q->queue_lock); - msleep(10); - spin_lock_irq(q->queue_lock); - elv_drain_elevator(q); - } + elv_quiesce_start(q); /* * Remember old elevator. @@ -1133,7 +1026,7 @@ static int elevator_switch(struct request_queue *q, struct elevator_type *new_e) */ elevator_exit(old_elevator); spin_lock_irq(q->queue_lock); - queue_flag_clear(QUEUE_FLAG_ELVSWITCH, q); + elv_quiesce_end(q); spin_unlock_irq(q->queue_lock); blk_add_trace_msg(q, "elv switch: %s", e->elevator_type->elevator_name); @@ -1162,6 +1055,9 @@ ssize_t elv_iosched_store(struct request_queue *q, const char *name, char elevator_name[ELV_NAME_MAX]; struct elevator_type *e; + if (!q->elevator) + return count; + strlcpy(elevator_name, name, sizeof(elevator_name)); strstrip(elevator_name); @@ -1184,11 +1080,16 @@ ssize_t elv_iosched_store(struct request_queue *q, const char *name, ssize_t elv_iosched_show(struct request_queue *q, char *name) { - elevator_t *e = q->elevator; - struct elevator_type *elv = e->elevator_type; + struct elevator_queue *e = q->elevator; + struct elevator_type *elv; struct elevator_type *__e; int len = 0; + if (!q->elevator) + return sprintf(name, "none\n"); + + elv = e->elevator_type; + spin_lock(&elv_list_lock); list_for_each_entry(__e, &elv_list, list) { if (!strcmp(elv->elevator_name, __e->elevator_name))