X-Git-Url: http://pilppa.org/gitweb/?a=blobdiff_plain;f=block%2Fcfq-iosched.c;h=ec24284e9d397048f4c4e5ee162363adca45d8b6;hb=89850f7ee905410c89f9295e89dc4c33502a34ac;hp=3a3aee08ec5f4850f0a1877b3bdf86d9b03d9625;hpb=115b384cf87249d76adb0b21aca11ee22128927d;p=linux-2.6-omap-h63xx.git diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index 3a3aee08ec5..ec24284e9d3 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -17,7 +17,6 @@ * tunables */ static const int cfq_quantum = 4; /* max queue in one round of service */ -static const int cfq_queued = 8; /* minimum rq allocate limit per-queue*/ static const int cfq_fifo_expire[2] = { HZ / 4, HZ / 8 }; static const int cfq_back_max = 16 * 1024; /* maximum backwards seek, in KiB */ static const int cfq_back_penalty = 2; /* penalty of a backwards seek */ @@ -41,28 +40,11 @@ static DEFINE_SPINLOCK(cfq_exit_lock); #define CFQ_QHASH_ENTRIES (1 << CFQ_QHASH_SHIFT) #define list_entry_qhash(entry) hlist_entry((entry), struct cfq_queue, cfq_hash) -/* - * for the hash of crq inside the cfqq - */ -#define CFQ_MHASH_SHIFT 6 -#define CFQ_MHASH_BLOCK(sec) ((sec) >> 3) -#define CFQ_MHASH_ENTRIES (1 << CFQ_MHASH_SHIFT) -#define CFQ_MHASH_FN(sec) hash_long(CFQ_MHASH_BLOCK(sec), CFQ_MHASH_SHIFT) -#define rq_hash_key(rq) ((rq)->sector + (rq)->nr_sectors) -#define list_entry_hash(ptr) hlist_entry((ptr), struct cfq_rq, hash) - #define list_entry_cfqq(ptr) list_entry((ptr), struct cfq_queue, cfq_list) -#define list_entry_fifo(ptr) list_entry((ptr), struct request, queuelist) -#define RQ_DATA(rq) (rq)->elevator_private +#define RQ_CIC(rq) ((struct cfq_io_context*)(rq)->elevator_private) +#define RQ_CFQQ(rq) ((rq)->elevator_private2) -/* - * rb-tree defines - */ -#define rb_entry_crq(node) rb_entry((node), struct cfq_rq, rb_node) -#define rq_rb_key(rq) (rq)->sector - -static kmem_cache_t *crq_pool; static kmem_cache_t *cfq_pool; static kmem_cache_t *cfq_ioc_pool; @@ -71,7 +53,6 @@ static struct completion *ioc_gone; #define CFQ_PRIO_LISTS IOPRIO_BE_NR #define cfq_class_idle(cfqq) ((cfqq)->ioprio_class == IOPRIO_CLASS_IDLE) -#define cfq_class_be(cfqq) ((cfqq)->ioprio_class == IOPRIO_CLASS_BE) #define cfq_class_rt(cfqq) ((cfqq)->ioprio_class == IOPRIO_CLASS_RT) #define ASYNC (0) @@ -112,19 +93,9 @@ struct cfq_data { */ struct hlist_head *cfq_hash; - /* - * global crq hash for all queues - */ - struct hlist_head *crq_hash; - - mempool_t *crq_pool; - int rq_in_driver; int hw_tag; - /* - * schedule slice state info - */ /* * idle window management */ @@ -141,13 +112,10 @@ struct cfq_data { sector_t last_sector; unsigned long last_end_request; - unsigned int rq_starved; - /* * tunables, see top of file */ unsigned int cfq_quantum; - unsigned int cfq_queued; unsigned int cfq_fifo_expire[2]; unsigned int cfq_back_penalty; unsigned int cfq_back_max; @@ -175,7 +143,7 @@ struct cfq_queue { /* sorted list of pending requests */ struct rb_root sort_list; /* if fifo isn't expired, next request to serve */ - struct cfq_rq *next_crq; + struct request *next_rq; /* requests queued in sort_list */ int queued[2]; /* currently allocated requests */ @@ -199,18 +167,6 @@ struct cfq_queue { unsigned int flags; }; -struct cfq_rq { - struct rb_node rb_node; - sector_t rb_key; - struct request *request; - struct hlist_node hash; - - struct cfq_queue *cfq_queue; - struct cfq_io_context *io_context; - - unsigned int crq_flags; -}; - enum cfqq_state_flags { CFQ_CFQQ_FLAG_on_rr = 0, CFQ_CFQQ_FLAG_wait_request, @@ -246,67 +202,10 @@ CFQ_CFQQ_FNS(idle_window); CFQ_CFQQ_FNS(prio_changed); #undef CFQ_CFQQ_FNS -enum cfq_rq_state_flags { - CFQ_CRQ_FLAG_is_sync = 0, -}; - -#define CFQ_CRQ_FNS(name) \ -static inline void cfq_mark_crq_##name(struct cfq_rq *crq) \ -{ \ - crq->crq_flags |= (1 << CFQ_CRQ_FLAG_##name); \ -} \ -static inline void cfq_clear_crq_##name(struct cfq_rq *crq) \ -{ \ - crq->crq_flags &= ~(1 << CFQ_CRQ_FLAG_##name); \ -} \ -static inline int cfq_crq_##name(const struct cfq_rq *crq) \ -{ \ - return (crq->crq_flags & (1 << CFQ_CRQ_FLAG_##name)) != 0; \ -} - -CFQ_CRQ_FNS(is_sync); -#undef CFQ_CRQ_FNS - static struct cfq_queue *cfq_find_cfq_hash(struct cfq_data *, unsigned int, unsigned short); -static void cfq_dispatch_insert(request_queue_t *, struct cfq_rq *); +static void cfq_dispatch_insert(request_queue_t *, struct request *); static struct cfq_queue *cfq_get_queue(struct cfq_data *cfqd, unsigned int key, struct task_struct *tsk, gfp_t gfp_mask); -/* - * lots of deadline iosched dupes, can be abstracted later... - */ -static inline void cfq_del_crq_hash(struct cfq_rq *crq) -{ - hlist_del_init(&crq->hash); -} - -static inline void cfq_add_crq_hash(struct cfq_data *cfqd, struct cfq_rq *crq) -{ - const int hash_idx = CFQ_MHASH_FN(rq_hash_key(crq->request)); - - hlist_add_head(&crq->hash, &cfqd->crq_hash[hash_idx]); -} - -static struct request *cfq_find_rq_hash(struct cfq_data *cfqd, sector_t offset) -{ - struct hlist_head *hash_list = &cfqd->crq_hash[CFQ_MHASH_FN(offset)]; - struct hlist_node *entry, *next; - - hlist_for_each_safe(entry, next, hash_list) { - struct cfq_rq *crq = list_entry_hash(entry); - struct request *__rq = crq->request; - - if (!rq_mergeable(__rq)) { - cfq_del_crq_hash(crq); - continue; - } - - if (rq_hash_key(__rq) == offset) - return __rq; - } - - return NULL; -} - /* * scheduler run of queue, if there are requests pending and no one in the * driver that will restart queueing @@ -333,12 +232,12 @@ static inline pid_t cfq_queue_pid(struct task_struct *task, int rw) } /* - * Lifted from AS - choose which of crq1 and crq2 that is best served now. + * Lifted from AS - choose which of rq1 and rq2 that is best served now. * We choose the request that is closest to the head right now. Distance * behind the head is penalized and only allowed to a certain extent. */ -static struct cfq_rq * -cfq_choose_req(struct cfq_data *cfqd, struct cfq_rq *crq1, struct cfq_rq *crq2) +static struct request * +cfq_choose_req(struct cfq_data *cfqd, struct request *rq1, struct request *rq2) { sector_t last, s1, s2, d1 = 0, d2 = 0; unsigned long back_max; @@ -346,18 +245,18 @@ cfq_choose_req(struct cfq_data *cfqd, struct cfq_rq *crq1, struct cfq_rq *crq2) #define CFQ_RQ2_WRAP 0x02 /* request 2 wraps */ unsigned wrap = 0; /* bit mask: requests behind the disk head? */ - if (crq1 == NULL || crq1 == crq2) - return crq2; - if (crq2 == NULL) - return crq1; + if (rq1 == NULL || rq1 == rq2) + return rq2; + if (rq2 == NULL) + return rq1; - if (cfq_crq_is_sync(crq1) && !cfq_crq_is_sync(crq2)) - return crq1; - else if (cfq_crq_is_sync(crq2) && !cfq_crq_is_sync(crq1)) - return crq2; + if (rq_is_sync(rq1) && !rq_is_sync(rq2)) + return rq1; + else if (rq_is_sync(rq2) && !rq_is_sync(rq1)) + return rq2; - s1 = crq1->request->sector; - s2 = crq2->request->sector; + s1 = rq1->sector; + s2 = rq2->sector; last = cfqd->last_sector; @@ -392,23 +291,23 @@ cfq_choose_req(struct cfq_data *cfqd, struct cfq_rq *crq1, struct cfq_rq *crq2) * check two variables for all permutations: --> faster! */ switch (wrap) { - case 0: /* common case for CFQ: crq1 and crq2 not wrapped */ + case 0: /* common case for CFQ: rq1 and rq2 not wrapped */ if (d1 < d2) - return crq1; + return rq1; else if (d2 < d1) - return crq2; + return rq2; else { if (s1 >= s2) - return crq1; + return rq1; else - return crq2; + return rq2; } case CFQ_RQ2_WRAP: - return crq1; + return rq1; case CFQ_RQ1_WRAP: - return crq2; - case (CFQ_RQ1_WRAP|CFQ_RQ2_WRAP): /* both crqs wrapped */ + return rq2; + case (CFQ_RQ1_WRAP|CFQ_RQ2_WRAP): /* both rqs wrapped */ default: /* * Since both rqs are wrapped, @@ -417,44 +316,37 @@ cfq_choose_req(struct cfq_data *cfqd, struct cfq_rq *crq1, struct cfq_rq *crq2) * since back seek takes more time than forward. */ if (s1 <= s2) - return crq1; + return rq1; else - return crq2; + return rq2; } } /* * would be nice to take fifo expire time into account as well */ -static struct cfq_rq * -cfq_find_next_crq(struct cfq_data *cfqd, struct cfq_queue *cfqq, - struct cfq_rq *last) +static struct request * +cfq_find_next_rq(struct cfq_data *cfqd, struct cfq_queue *cfqq, + struct request *last) { - struct cfq_rq *crq_next = NULL, *crq_prev = NULL; - struct rb_node *rbnext, *rbprev; - - if (!(rbnext = rb_next(&last->rb_node))) { - rbnext = rb_first(&cfqq->sort_list); - if (rbnext == &last->rb_node) - rbnext = NULL; - } + struct rb_node *rbnext = rb_next(&last->rb_node); + struct rb_node *rbprev = rb_prev(&last->rb_node); + struct request *next = NULL, *prev = NULL; - rbprev = rb_prev(&last->rb_node); + BUG_ON(RB_EMPTY_NODE(&last->rb_node)); if (rbprev) - crq_prev = rb_entry_crq(rbprev); - if (rbnext) - crq_next = rb_entry_crq(rbnext); - - return cfq_choose_req(cfqd, crq_next, crq_prev); -} + prev = rb_entry_rq(rbprev); -static void cfq_update_next_crq(struct cfq_rq *crq) -{ - struct cfq_queue *cfqq = crq->cfq_queue; + if (rbnext) + next = rb_entry_rq(rbnext); + else { + rbnext = rb_first(&cfqq->sort_list); + if (rbnext && rbnext != &last->rb_node) + next = rb_entry_rq(rbnext); + } - if (cfqq->next_crq == crq) - cfqq->next_crq = cfq_find_next_crq(cfqq->cfqd, cfqq, crq); + return cfq_choose_req(cfqd, next, prev); } static void cfq_resort_rr_list(struct cfq_queue *cfqq, int preempted) @@ -540,81 +432,43 @@ cfq_del_cfqq_rr(struct cfq_data *cfqd, struct cfq_queue *cfqq) /* * rb tree support functions */ -static inline void cfq_del_crq_rb(struct cfq_rq *crq) +static inline void cfq_del_rq_rb(struct request *rq) { - struct cfq_queue *cfqq = crq->cfq_queue; + struct cfq_queue *cfqq = RQ_CFQQ(rq); struct cfq_data *cfqd = cfqq->cfqd; - const int sync = cfq_crq_is_sync(crq); + const int sync = rq_is_sync(rq); BUG_ON(!cfqq->queued[sync]); cfqq->queued[sync]--; - cfq_update_next_crq(crq); - - rb_erase(&crq->rb_node, &cfqq->sort_list); + elv_rb_del(&cfqq->sort_list, rq); if (cfq_cfqq_on_rr(cfqq) && RB_EMPTY_ROOT(&cfqq->sort_list)) cfq_del_cfqq_rr(cfqd, cfqq); } -static struct cfq_rq * -__cfq_add_crq_rb(struct cfq_rq *crq) +static void cfq_add_rq_rb(struct request *rq) { - struct rb_node **p = &crq->cfq_queue->sort_list.rb_node; - struct rb_node *parent = NULL; - struct cfq_rq *__crq; - - while (*p) { - parent = *p; - __crq = rb_entry_crq(parent); - - if (crq->rb_key < __crq->rb_key) - p = &(*p)->rb_left; - else if (crq->rb_key > __crq->rb_key) - p = &(*p)->rb_right; - else - return __crq; - } - - rb_link_node(&crq->rb_node, parent, p); - return NULL; -} - -static void cfq_add_crq_rb(struct cfq_rq *crq) -{ - struct cfq_queue *cfqq = crq->cfq_queue; + struct cfq_queue *cfqq = RQ_CFQQ(rq); struct cfq_data *cfqd = cfqq->cfqd; - struct request *rq = crq->request; - struct cfq_rq *__alias; + struct request *__alias; - crq->rb_key = rq_rb_key(rq); - cfqq->queued[cfq_crq_is_sync(crq)]++; + cfqq->queued[rq_is_sync(rq)]++; /* * looks a little odd, but the first insert might return an alias. * if that happens, put the alias on the dispatch list */ - while ((__alias = __cfq_add_crq_rb(crq)) != NULL) + while ((__alias = elv_rb_add(&cfqq->sort_list, rq)) != NULL) cfq_dispatch_insert(cfqd->queue, __alias); - - rb_insert_color(&crq->rb_node, &cfqq->sort_list); - - if (!cfq_cfqq_on_rr(cfqq)) - cfq_add_cfqq_rr(cfqd, cfqq); - - /* - * check if this request is a better next-serve candidate - */ - cfqq->next_crq = cfq_choose_req(cfqd, cfqq->next_crq, crq); } static inline void -cfq_reposition_crq_rb(struct cfq_queue *cfqq, struct cfq_rq *crq) +cfq_reposition_rq_rb(struct cfq_queue *cfqq, struct request *rq) { - rb_erase(&crq->rb_node, &cfqq->sort_list); - cfqq->queued[cfq_crq_is_sync(crq)]--; - - cfq_add_crq_rb(crq); + elv_rb_del(&cfqq->sort_list, rq); + cfqq->queued[rq_is_sync(rq)]--; + cfq_add_rq_rb(rq); } static struct request * @@ -623,27 +477,14 @@ cfq_find_rq_fmerge(struct cfq_data *cfqd, struct bio *bio) struct task_struct *tsk = current; pid_t key = cfq_queue_pid(tsk, bio_data_dir(bio)); struct cfq_queue *cfqq; - struct rb_node *n; - sector_t sector; cfqq = cfq_find_cfq_hash(cfqd, key, tsk->ioprio); - if (!cfqq) - goto out; - - sector = bio->bi_sector + bio_sectors(bio); - n = cfqq->sort_list.rb_node; - while (n) { - struct cfq_rq *crq = rb_entry_crq(n); + if (cfqq) { + sector_t sector = bio->bi_sector + bio_sectors(bio); - if (sector < crq->rb_key) - n = n->rb_left; - else if (sector > crq->rb_key) - n = n->rb_right; - else - return crq->request; + return elv_rb_find(&cfqq->sort_list, sector); } -out: return NULL; } @@ -673,11 +514,13 @@ static void cfq_deactivate_request(request_queue_t *q, struct request *rq) static void cfq_remove_request(struct request *rq) { - struct cfq_rq *crq = RQ_DATA(rq); + struct cfq_queue *cfqq = RQ_CFQQ(rq); + + if (cfqq->next_rq == rq) + cfqq->next_rq = cfq_find_next_rq(cfqq->cfqd, cfqq, rq); list_del_init(&rq->queuelist); - cfq_del_crq_rb(crq); - cfq_del_crq_hash(crq); + cfq_del_rq_rb(rq); } static int @@ -685,39 +528,23 @@ cfq_merge(request_queue_t *q, struct request **req, struct bio *bio) { struct cfq_data *cfqd = q->elevator->elevator_data; struct request *__rq; - int ret; - - __rq = cfq_find_rq_hash(cfqd, bio->bi_sector); - if (__rq && elv_rq_merge_ok(__rq, bio)) { - ret = ELEVATOR_BACK_MERGE; - goto out; - } __rq = cfq_find_rq_fmerge(cfqd, bio); if (__rq && elv_rq_merge_ok(__rq, bio)) { - ret = ELEVATOR_FRONT_MERGE; - goto out; + *req = __rq; + return ELEVATOR_FRONT_MERGE; } return ELEVATOR_NO_MERGE; -out: - *req = __rq; - return ret; } -static void cfq_merged_request(request_queue_t *q, struct request *req) +static void cfq_merged_request(request_queue_t *q, struct request *req, + int type) { - struct cfq_data *cfqd = q->elevator->elevator_data; - struct cfq_rq *crq = RQ_DATA(req); - - cfq_del_crq_hash(crq); - cfq_add_crq_hash(cfqd, crq); - - if (rq_rb_key(req) != crq->rb_key) { - struct cfq_queue *cfqq = crq->cfq_queue; + if (type == ELEVATOR_FRONT_MERGE) { + struct cfq_queue *cfqq = RQ_CFQQ(req); - cfq_update_next_crq(crq); - cfq_reposition_crq_rb(cfqq, crq); + cfq_reposition_rq_rb(cfqq, req); } } @@ -725,8 +552,6 @@ static void cfq_merged_requests(request_queue_t *q, struct request *rq, struct request *next) { - cfq_merged_request(q, rq); - /* * reposition in fifo if next is older than rq */ @@ -868,26 +693,25 @@ static struct cfq_queue *cfq_set_active_queue(struct cfq_data *cfqd) { struct cfq_queue *cfqq = NULL; - /* - * if current list is non-empty, grab first entry. if it is empty, - * get next prio level and grab first entry then if any are spliced - */ - if (!list_empty(&cfqd->cur_rr) || cfq_get_next_prio_level(cfqd) != -1) + if (!list_empty(&cfqd->cur_rr) || cfq_get_next_prio_level(cfqd) != -1) { + /* + * if current list is non-empty, grab first entry. if it is + * empty, get next prio level and grab first entry then if any + * are spliced + */ cfqq = list_entry_cfqq(cfqd->cur_rr.next); - - /* - * If no new queues are available, check if the busy list has some - * before falling back to idle io. - */ - if (!cfqq && !list_empty(&cfqd->busy_rr)) + } else if (!list_empty(&cfqd->busy_rr)) { + /* + * If no new queues are available, check if the busy list has + * some before falling back to idle io. + */ cfqq = list_entry_cfqq(cfqd->busy_rr.next); - - /* - * if we have idle queues and no rt or be queues had pending - * requests, either allow immediate service if the grace period - * has passed or arm the idle grace timer - */ - if (!cfqq && !list_empty(&cfqd->idle_rr)) { + } else if (!list_empty(&cfqd->idle_rr)) { + /* + * if we have idle queues and no rt or be queues had pending + * requests, either allow immediate service if the grace period + * has passed or arm the idle grace timer + */ unsigned long end = cfqd->last_end_request + CFQ_IDLE_GRACE; if (time_after_eq(jiffies, end)) @@ -942,16 +766,14 @@ static int cfq_arm_slice_timer(struct cfq_data *cfqd, struct cfq_queue *cfqq) return 1; } -static void cfq_dispatch_insert(request_queue_t *q, struct cfq_rq *crq) +static void cfq_dispatch_insert(request_queue_t *q, struct request *rq) { struct cfq_data *cfqd = q->elevator->elevator_data; - struct cfq_queue *cfqq = crq->cfq_queue; - struct request *rq; + struct cfq_queue *cfqq = RQ_CFQQ(rq); - cfqq->next_crq = cfq_find_next_crq(cfqd, cfqq, crq); - cfq_remove_request(crq->request); - cfqq->on_dispatch[cfq_crq_is_sync(crq)]++; - elv_dispatch_sort(q, crq->request); + cfq_remove_request(rq); + cfqq->on_dispatch[rq_is_sync(rq)]++; + elv_dispatch_sort(q, rq); rq = list_entry(q->queue_head.prev, struct request, queuelist); cfqd->last_sector = rq->sector + rq->nr_sectors; @@ -960,24 +782,23 @@ static void cfq_dispatch_insert(request_queue_t *q, struct cfq_rq *crq) /* * return expired entry, or NULL to just start from scratch in rbtree */ -static inline struct cfq_rq *cfq_check_fifo(struct cfq_queue *cfqq) +static inline struct request *cfq_check_fifo(struct cfq_queue *cfqq) { struct cfq_data *cfqd = cfqq->cfqd; struct request *rq; - struct cfq_rq *crq; + int fifo; if (cfq_cfqq_fifo_expire(cfqq)) return NULL; + if (list_empty(&cfqq->fifo)) + return NULL; - if (!list_empty(&cfqq->fifo)) { - int fifo = cfq_cfqq_class_sync(cfqq); + fifo = cfq_cfqq_class_sync(cfqq); + rq = rq_entry_fifo(cfqq->fifo.next); - crq = RQ_DATA(list_entry_fifo(cfqq->fifo.next)); - rq = crq->request; - if (time_after(jiffies, rq->start_time + cfqd->cfq_fifo_expire[fifo])) { - cfq_mark_cfqq_fifo_expire(cfqq); - return crq; - } + if (time_after(jiffies, rq->start_time + cfqd->cfq_fifo_expire[fifo])) { + cfq_mark_cfqq_fifo_expire(cfqq); + return rq; } return NULL; @@ -1063,25 +884,25 @@ __cfq_dispatch_requests(struct cfq_data *cfqd, struct cfq_queue *cfqq, BUG_ON(RB_EMPTY_ROOT(&cfqq->sort_list)); do { - struct cfq_rq *crq; + struct request *rq; /* * follow expired path, else get first next available */ - if ((crq = cfq_check_fifo(cfqq)) == NULL) - crq = cfqq->next_crq; + if ((rq = cfq_check_fifo(cfqq)) == NULL) + rq = cfqq->next_rq; /* * finally, insert request into driver dispatch list */ - cfq_dispatch_insert(cfqd->queue, crq); + cfq_dispatch_insert(cfqd->queue, rq); cfqd->dispatch_slice++; dispatched++; if (!cfqd->active_cic) { - atomic_inc(&crq->io_context->ioc->refcount); - cfqd->active_cic = crq->io_context; + atomic_inc(&RQ_CIC(rq)->ioc->refcount); + cfqd->active_cic = RQ_CIC(rq); } if (RB_EMPTY_ROOT(&cfqq->sort_list)) @@ -1112,13 +933,12 @@ static int cfq_forced_dispatch_cfqqs(struct list_head *list) { struct cfq_queue *cfqq, *next; - struct cfq_rq *crq; int dispatched; dispatched = 0; list_for_each_entry_safe(cfqq, next, list, cfq_list) { - while ((crq = cfqq->next_crq)) { - cfq_dispatch_insert(cfqq->cfqd->queue, crq); + while (cfqq->next_rq) { + cfq_dispatch_insert(cfqq->cfqd->queue, cfqq->next_rq); dispatched++; } BUG_ON(!list_empty(&cfqq->fifo)); @@ -1194,8 +1014,8 @@ cfq_dispatch_requests(request_queue_t *q, int force) } /* - * task holds one reference to the queue, dropped when task exits. each crq - * in-flight on this queue also holds a reference, dropped when crq is freed. + * task holds one reference to the queue, dropped when task exits. each rq + * in-flight on this queue also holds a reference, dropped when rq is freed. * * queue lock must be held here. */ @@ -1270,40 +1090,48 @@ static void cfq_trim(struct io_context *ioc) cfq_free_io_context(ioc); } -/* - * Called with interrupts disabled - */ -static void cfq_exit_single_io_context(struct cfq_io_context *cic) +static void cfq_exit_cfqq(struct cfq_data *cfqd, struct cfq_queue *cfqq) { - struct cfq_data *cfqd = cic->key; - request_queue_t *q; - - if (!cfqd) - return; - - q = cfqd->queue; - - WARN_ON(!irqs_disabled()); + if (unlikely(cfqq == cfqd->active_queue)) + __cfq_slice_expired(cfqd, cfqq, 0); - spin_lock(q->queue_lock); + cfq_put_queue(cfqq); +} +static void __cfq_exit_single_io_context(struct cfq_data *cfqd, + struct cfq_io_context *cic) +{ if (cic->cfqq[ASYNC]) { - if (unlikely(cic->cfqq[ASYNC] == cfqd->active_queue)) - __cfq_slice_expired(cfqd, cic->cfqq[ASYNC], 0); - cfq_put_queue(cic->cfqq[ASYNC]); + cfq_exit_cfqq(cfqd, cic->cfqq[ASYNC]); cic->cfqq[ASYNC] = NULL; } if (cic->cfqq[SYNC]) { - if (unlikely(cic->cfqq[SYNC] == cfqd->active_queue)) - __cfq_slice_expired(cfqd, cic->cfqq[SYNC], 0); - cfq_put_queue(cic->cfqq[SYNC]); + cfq_exit_cfqq(cfqd, cic->cfqq[SYNC]); cic->cfqq[SYNC] = NULL; } cic->key = NULL; list_del_init(&cic->queue_list); - spin_unlock(q->queue_lock); +} + + +/* + * Called with interrupts disabled + */ +static void cfq_exit_single_io_context(struct cfq_io_context *cic) +{ + struct cfq_data *cfqd = cic->key; + + WARN_ON(!irqs_disabled()); + + if (cfqd) { + request_queue_t *q = cfqd->queue; + + spin_lock(q->queue_lock); + __cfq_exit_single_io_context(cfqd, cic); + spin_unlock(q->queue_lock); + } } static void cfq_exit_io_context(struct io_context *ioc) @@ -1460,8 +1288,14 @@ retry: cfqq = new_cfqq; new_cfqq = NULL; } else if (gfp_mask & __GFP_WAIT) { + /* + * Inform the allocator of the fact that we will + * just repeat this allocation if it fails, to allow + * the allocator to do whatever it needs to attempt to + * free memory. + */ spin_unlock_irq(cfqd->queue->queue_lock); - new_cfqq = kmem_cache_alloc(cfq_pool, gfp_mask); + new_cfqq = kmem_cache_alloc(cfq_pool, gfp_mask|__GFP_NOFAIL); spin_lock_irq(cfqd->queue->queue_lock); goto retry; } else { @@ -1640,15 +1474,15 @@ cfq_update_io_thinktime(struct cfq_data *cfqd, struct cfq_io_context *cic) static void cfq_update_io_seektime(struct cfq_data *cfqd, struct cfq_io_context *cic, - struct cfq_rq *crq) + struct request *rq) { sector_t sdist; u64 total; - if (cic->last_request_pos < crq->request->sector) - sdist = crq->request->sector - cic->last_request_pos; + if (cic->last_request_pos < rq->sector) + sdist = rq->sector - cic->last_request_pos; else - sdist = cic->last_request_pos - crq->request->sector; + sdist = cic->last_request_pos - rq->sector; /* * Don't allow the seek distance to get too large from the @@ -1699,7 +1533,7 @@ cfq_update_idle_window(struct cfq_data *cfqd, struct cfq_queue *cfqq, */ static int cfq_should_preempt(struct cfq_data *cfqd, struct cfq_queue *new_cfqq, - struct cfq_rq *crq) + struct request *rq) { struct cfq_queue *cfqq = cfqd->active_queue; @@ -1718,7 +1552,7 @@ cfq_should_preempt(struct cfq_data *cfqd, struct cfq_queue *new_cfqq, */ if (new_cfqq->slice_left < cfqd->cfq_slice_idle) return 0; - if (cfq_crq_is_sync(crq) && !cfq_cfqq_sync(cfqq)) + if (rq_is_sync(rq) && !cfq_cfqq_sync(cfqq)) return 1; return 0; @@ -1757,20 +1591,26 @@ static void cfq_start_queueing(struct cfq_data *cfqd, struct cfq_queue *cfqq) } /* - * Called when a new fs request (crq) is added (to cfqq). Check if there's + * Called when a new fs request (rq) is added (to cfqq). Check if there's * something we should do about it */ static void -cfq_crq_enqueued(struct cfq_data *cfqd, struct cfq_queue *cfqq, - struct cfq_rq *crq) +cfq_rq_enqueued(struct cfq_data *cfqd, struct cfq_queue *cfqq, + struct request *rq) { - struct cfq_io_context *cic = crq->io_context; + struct cfq_io_context *cic = RQ_CIC(rq); + + /* + * check if this request is a better next-serve candidate)) { + */ + cfqq->next_rq = cfq_choose_req(cfqd, cfqq->next_rq, rq); + BUG_ON(!cfqq->next_rq); /* * we never wait for an async request and we don't allow preemption * of an async request. so just return early */ - if (!cfq_crq_is_sync(crq)) { + if (!rq_is_sync(rq)) { /* * sync process issued an async request, if it's waiting * then expire it and kick rq handling. @@ -1784,11 +1624,11 @@ cfq_crq_enqueued(struct cfq_data *cfqd, struct cfq_queue *cfqq, } cfq_update_io_thinktime(cfqd, cic); - cfq_update_io_seektime(cfqd, cic, crq); + cfq_update_io_seektime(cfqd, cic, rq); cfq_update_idle_window(cfqd, cfqq, cic); cic->last_queue = jiffies; - cic->last_request_pos = crq->request->sector + crq->request->nr_sectors; + cic->last_request_pos = rq->sector + rq->nr_sectors; if (cfqq == cfqd->active_queue) { /* @@ -1801,7 +1641,7 @@ cfq_crq_enqueued(struct cfq_data *cfqd, struct cfq_queue *cfqq, del_timer(&cfqd->idle_slice_timer); cfq_start_queueing(cfqd, cfqq); } - } else if (cfq_should_preempt(cfqd, cfqq, crq)) { + } else if (cfq_should_preempt(cfqd, cfqq, rq)) { /* * not the active queue - expire current slice if it is * idle and has expired it's mean thinktime or this new queue @@ -1816,27 +1656,25 @@ cfq_crq_enqueued(struct cfq_data *cfqd, struct cfq_queue *cfqq, static void cfq_insert_request(request_queue_t *q, struct request *rq) { struct cfq_data *cfqd = q->elevator->elevator_data; - struct cfq_rq *crq = RQ_DATA(rq); - struct cfq_queue *cfqq = crq->cfq_queue; + struct cfq_queue *cfqq = RQ_CFQQ(rq); cfq_init_prio_data(cfqq); - cfq_add_crq_rb(crq); + cfq_add_rq_rb(rq); - list_add_tail(&rq->queuelist, &cfqq->fifo); + if (!cfq_cfqq_on_rr(cfqq)) + cfq_add_cfqq_rr(cfqd, cfqq); - if (rq_mergeable(rq)) - cfq_add_crq_hash(cfqd, crq); + list_add_tail(&rq->queuelist, &cfqq->fifo); - cfq_crq_enqueued(cfqd, cfqq, crq); + cfq_rq_enqueued(cfqd, cfqq, rq); } static void cfq_completed_request(request_queue_t *q, struct request *rq) { - struct cfq_rq *crq = RQ_DATA(rq); - struct cfq_queue *cfqq = crq->cfq_queue; + struct cfq_queue *cfqq = RQ_CFQQ(rq); struct cfq_data *cfqd = cfqq->cfqd; - const int sync = cfq_crq_is_sync(crq); + const int sync = rq_is_sync(rq); unsigned long now; now = jiffies; @@ -1857,7 +1695,7 @@ static void cfq_completed_request(request_queue_t *q, struct request *rq) } if (sync) - crq->io_context->last_end_request = now; + RQ_CIC(rq)->last_end_request = now; /* * If this is the active queue, check if it needs to be expired, @@ -1873,30 +1711,6 @@ static void cfq_completed_request(request_queue_t *q, struct request *rq) } } -static struct request * -cfq_former_request(request_queue_t *q, struct request *rq) -{ - struct cfq_rq *crq = RQ_DATA(rq); - struct rb_node *rbprev = rb_prev(&crq->rb_node); - - if (rbprev) - return rb_entry_crq(rbprev)->request; - - return NULL; -} - -static struct request * -cfq_latter_request(request_queue_t *q, struct request *rq) -{ - struct cfq_rq *crq = RQ_DATA(rq); - struct rb_node *rbnext = rb_next(&crq->rb_node); - - if (rbnext) - return rb_entry_crq(rbnext)->request; - - return NULL; -} - /* * we temporarily boost lower priority queues if they are holding fs exclusive * resources. they are boosted to normal prio (CLASS_BE/4) @@ -1933,9 +1747,7 @@ static void cfq_prio_boost(struct cfq_queue *cfqq) cfq_resort_rr_list(cfqq, 0); } -static inline int -__cfq_may_queue(struct cfq_data *cfqd, struct cfq_queue *cfqq, - struct task_struct *task, int rw) +static inline int __cfq_may_queue(struct cfq_queue *cfqq) { if ((cfq_cfqq_wait_request(cfqq) || cfq_cfqq_must_alloc(cfqq)) && !cfq_cfqq_must_alloc_slice(cfqq)) { @@ -1946,7 +1758,7 @@ __cfq_may_queue(struct cfq_data *cfqd, struct cfq_queue *cfqq, return ELV_MQUEUE_MAY; } -static int cfq_may_queue(request_queue_t *q, int rw, struct bio *bio) +static int cfq_may_queue(request_queue_t *q, int rw) { struct cfq_data *cfqd = q->elevator->elevator_data; struct task_struct *tsk = current; @@ -1963,48 +1775,30 @@ static int cfq_may_queue(request_queue_t *q, int rw, struct bio *bio) cfq_init_prio_data(cfqq); cfq_prio_boost(cfqq); - return __cfq_may_queue(cfqd, cfqq, tsk, rw); + return __cfq_may_queue(cfqq); } return ELV_MQUEUE_MAY; } -static void cfq_check_waiters(request_queue_t *q, struct cfq_queue *cfqq) -{ - struct cfq_data *cfqd = q->elevator->elevator_data; - - if (unlikely(cfqd->rq_starved)) { - struct request_list *rl = &q->rq; - - smp_mb(); - if (waitqueue_active(&rl->wait[READ])) - wake_up(&rl->wait[READ]); - if (waitqueue_active(&rl->wait[WRITE])) - wake_up(&rl->wait[WRITE]); - } -} - /* * queue lock held here */ static void cfq_put_request(request_queue_t *q, struct request *rq) { - struct cfq_data *cfqd = q->elevator->elevator_data; - struct cfq_rq *crq = RQ_DATA(rq); + struct cfq_queue *cfqq = RQ_CFQQ(rq); - if (crq) { - struct cfq_queue *cfqq = crq->cfq_queue; + if (cfqq) { const int rw = rq_data_dir(rq); BUG_ON(!cfqq->allocated[rw]); cfqq->allocated[rw]--; - put_io_context(crq->io_context->ioc); + put_io_context(RQ_CIC(rq)->ioc); - mempool_free(crq, cfqd->crq_pool); rq->elevator_private = NULL; + rq->elevator_private2 = NULL; - cfq_check_waiters(q, cfqq); cfq_put_queue(cfqq); } } @@ -2013,8 +1807,7 @@ static void cfq_put_request(request_queue_t *q, struct request *rq) * Allocate cfq data structures associated with this request. */ static int -cfq_set_request(request_queue_t *q, struct request *rq, struct bio *bio, - gfp_t gfp_mask) +cfq_set_request(request_queue_t *q, struct request *rq, gfp_t gfp_mask) { struct cfq_data *cfqd = q->elevator->elevator_data; struct task_struct *tsk = current; @@ -2022,7 +1815,6 @@ cfq_set_request(request_queue_t *q, struct request *rq, struct bio *bio, const int rw = rq_data_dir(rq); pid_t key = cfq_queue_pid(tsk, rw); struct cfq_queue *cfqq; - struct cfq_rq *crq; unsigned long flags; int is_sync = key != CFQ_KEY_ASYNC; @@ -2046,42 +1838,18 @@ cfq_set_request(request_queue_t *q, struct request *rq, struct bio *bio, cfqq->allocated[rw]++; cfq_clear_cfqq_must_alloc(cfqq); - cfqd->rq_starved = 0; atomic_inc(&cfqq->ref); - spin_unlock_irqrestore(q->queue_lock, flags); - crq = mempool_alloc(cfqd->crq_pool, gfp_mask); - if (crq) { - RB_CLEAR_NODE(&crq->rb_node); - crq->rb_key = 0; - crq->request = rq; - INIT_HLIST_NODE(&crq->hash); - crq->cfq_queue = cfqq; - crq->io_context = cic; - - if (is_sync) - cfq_mark_crq_is_sync(crq); - else - cfq_clear_crq_is_sync(crq); + spin_unlock_irqrestore(q->queue_lock, flags); - rq->elevator_private = crq; - return 0; - } + rq->elevator_private = cic; + rq->elevator_private2 = cfqq; + return 0; - spin_lock_irqsave(q->queue_lock, flags); - cfqq->allocated[rw]--; - if (!(cfqq->allocated[0] + cfqq->allocated[1])) - cfq_mark_cfqq_must_alloc(cfqq); - cfq_put_queue(cfqq); queue_fail: if (cic) put_io_context(cic->ioc); - /* - * mark us rq allocation starved. we need to kickstart the process - * ourselves if there are no pending requests that can do it for us. - * that would be an extremely rare OOM situation - */ - cfqd->rq_starved = 1; + cfq_schedule_dispatch(cfqd); spin_unlock_irqrestore(q->queue_lock, flags); return 1; @@ -2090,25 +1858,9 @@ queue_fail: static void cfq_kick_queue(void *data) { request_queue_t *q = data; - struct cfq_data *cfqd = q->elevator->elevator_data; unsigned long flags; spin_lock_irqsave(q->queue_lock, flags); - - if (cfqd->rq_starved) { - struct request_list *rl = &q->rq; - - /* - * we aren't guaranteed to get a request after this, but we - * have to be opportunistic - */ - smp_mb(); - if (waitqueue_active(&rl->wait[READ])) - wake_up(&rl->wait[READ]); - if (waitqueue_active(&rl->wait[WRITE])) - wake_up(&rl->wait[WRITE]); - } - blk_remove_plug(q); q->request_fn(q); spin_unlock_irqrestore(q->queue_lock, flags); @@ -2203,16 +1955,8 @@ static void cfq_exit_queue(elevator_t *e) struct cfq_io_context *cic = list_entry(cfqd->cic_list.next, struct cfq_io_context, queue_list); - if (cic->cfqq[ASYNC]) { - cfq_put_queue(cic->cfqq[ASYNC]); - cic->cfqq[ASYNC] = NULL; - } - if (cic->cfqq[SYNC]) { - cfq_put_queue(cic->cfqq[SYNC]); - cic->cfqq[SYNC] = NULL; - } - cic->key = NULL; - list_del_init(&cic->queue_list); + + __cfq_exit_single_io_context(cfqd, cic); } spin_unlock_irq(q->queue_lock); @@ -2220,8 +1964,6 @@ static void cfq_exit_queue(elevator_t *e) cfq_shutdown_timer_wq(cfqd); - mempool_destroy(cfqd->crq_pool); - kfree(cfqd->crq_hash); kfree(cfqd->cfq_hash); kfree(cfqd); } @@ -2246,20 +1988,10 @@ static void *cfq_init_queue(request_queue_t *q, elevator_t *e) INIT_LIST_HEAD(&cfqd->empty_list); INIT_LIST_HEAD(&cfqd->cic_list); - cfqd->crq_hash = kmalloc(sizeof(struct hlist_head) * CFQ_MHASH_ENTRIES, GFP_KERNEL); - if (!cfqd->crq_hash) - goto out_crqhash; - cfqd->cfq_hash = kmalloc(sizeof(struct hlist_head) * CFQ_QHASH_ENTRIES, GFP_KERNEL); if (!cfqd->cfq_hash) - goto out_cfqhash; - - cfqd->crq_pool = mempool_create_slab_pool(BLKDEV_MIN_RQ, crq_pool); - if (!cfqd->crq_pool) - goto out_crqpool; + goto out_free; - for (i = 0; i < CFQ_MHASH_ENTRIES; i++) - INIT_HLIST_HEAD(&cfqd->crq_hash[i]); for (i = 0; i < CFQ_QHASH_ENTRIES; i++) INIT_HLIST_HEAD(&cfqd->cfq_hash[i]); @@ -2275,7 +2007,6 @@ static void *cfq_init_queue(request_queue_t *q, elevator_t *e) INIT_WORK(&cfqd->unplug_work, cfq_kick_queue, q); - cfqd->cfq_queued = cfq_queued; cfqd->cfq_quantum = cfq_quantum; cfqd->cfq_fifo_expire[0] = cfq_fifo_expire[0]; cfqd->cfq_fifo_expire[1] = cfq_fifo_expire[1]; @@ -2287,19 +2018,13 @@ static void *cfq_init_queue(request_queue_t *q, elevator_t *e) cfqd->cfq_slice_idle = cfq_slice_idle; return cfqd; -out_crqpool: - kfree(cfqd->cfq_hash); -out_cfqhash: - kfree(cfqd->crq_hash); -out_crqhash: +out_free: kfree(cfqd); return NULL; } static void cfq_slab_kill(void) { - if (crq_pool) - kmem_cache_destroy(crq_pool); if (cfq_pool) kmem_cache_destroy(cfq_pool); if (cfq_ioc_pool) @@ -2308,11 +2033,6 @@ static void cfq_slab_kill(void) static int __init cfq_slab_setup(void) { - crq_pool = kmem_cache_create("crq_pool", sizeof(struct cfq_rq), 0, 0, - NULL, NULL); - if (!crq_pool) - goto fail; - cfq_pool = kmem_cache_create("cfq_pool", sizeof(struct cfq_queue), 0, 0, NULL, NULL); if (!cfq_pool) @@ -2358,7 +2078,6 @@ static ssize_t __FUNC(elevator_t *e, char *page) \ return cfq_var_show(__data, (page)); \ } SHOW_FUNCTION(cfq_quantum_show, cfqd->cfq_quantum, 0); -SHOW_FUNCTION(cfq_queued_show, cfqd->cfq_queued, 0); SHOW_FUNCTION(cfq_fifo_expire_sync_show, cfqd->cfq_fifo_expire[1], 1); SHOW_FUNCTION(cfq_fifo_expire_async_show, cfqd->cfq_fifo_expire[0], 1); SHOW_FUNCTION(cfq_back_seek_max_show, cfqd->cfq_back_max, 0); @@ -2386,7 +2105,6 @@ static ssize_t __FUNC(elevator_t *e, const char *page, size_t count) \ return ret; \ } STORE_FUNCTION(cfq_quantum_store, &cfqd->cfq_quantum, 1, UINT_MAX, 0); -STORE_FUNCTION(cfq_queued_store, &cfqd->cfq_queued, 1, UINT_MAX, 0); STORE_FUNCTION(cfq_fifo_expire_sync_store, &cfqd->cfq_fifo_expire[1], 1, UINT_MAX, 1); STORE_FUNCTION(cfq_fifo_expire_async_store, &cfqd->cfq_fifo_expire[0], 1, UINT_MAX, 1); STORE_FUNCTION(cfq_back_seek_max_store, &cfqd->cfq_back_max, 0, UINT_MAX, 0); @@ -2402,7 +2120,6 @@ STORE_FUNCTION(cfq_slice_async_rq_store, &cfqd->cfq_slice_async_rq, 1, UINT_MAX, static struct elv_fs_entry cfq_attrs[] = { CFQ_ATTR(quantum), - CFQ_ATTR(queued), CFQ_ATTR(fifo_expire_sync), CFQ_ATTR(fifo_expire_async), CFQ_ATTR(back_seek_max), @@ -2425,8 +2142,8 @@ static struct elevator_type iosched_cfq = { .elevator_deactivate_req_fn = cfq_deactivate_request, .elevator_queue_empty_fn = cfq_queue_empty, .elevator_completed_req_fn = cfq_completed_request, - .elevator_former_req_fn = cfq_former_request, - .elevator_latter_req_fn = cfq_latter_request, + .elevator_former_req_fn = elv_rb_former_request, + .elevator_latter_req_fn = elv_rb_latter_request, .elevator_set_req_fn = cfq_set_request, .elevator_put_req_fn = cfq_put_request, .elevator_may_queue_fn = cfq_may_queue,