X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=block%2Fcfq-iosched.c;h=d3d76136f53adea6293244f7cd9a9aa07f24b4d0;hb=b2cfcd75df77b80d9cc3fa84190a350dfa79eb93;hp=8e9d84825e1c519500288da6602b208fcec33995;hpb=48e49ead3e92d53196a78c42cf24c0eed6ca98dd;p=pandora-kernel.git diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index 8e9d84825e1c..d3d76136f53a 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -4,9 +4,8 @@ * Based on ideas from a previously unfinished io * scheduler (round robin per-process disk scheduling) and Andrea Arcangeli. * - * Copyright (C) 2003 Jens Axboe + * Copyright (C) 2003 Jens Axboe */ -#include #include #include #include @@ -18,7 +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 */ @@ -26,15 +24,13 @@ static const int cfq_back_penalty = 2; /* penalty of a backwards seek */ static const int cfq_slice_sync = HZ / 10; static int cfq_slice_async = HZ / 25; static const int cfq_slice_async_rq = 2; -static int cfq_slice_idle = HZ / 70; +static int cfq_slice_idle = HZ / 125; #define CFQ_IDLE_GRACE (HZ / 10) #define CFQ_SLICE_SCALE (5) #define CFQ_KEY_ASYNC (0) -static DEFINE_SPINLOCK(cfq_exit_lock); - /* * for the hash of cfqq inside the cfqd */ @@ -42,47 +38,19 @@ 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_NONE (2) -#define RB_EMPTY(node) ((node)->rb_node == NULL) -#define RB_CLEAR_COLOR(node) (node)->rb_color = RB_NONE -#define RB_CLEAR(node) do { \ - (node)->rb_parent = NULL; \ - RB_CLEAR_COLOR((node)); \ - (node)->rb_right = NULL; \ - (node)->rb_left = NULL; \ -} while (0) -#define RB_CLEAR_ROOT(root) ((root)->rb_node = NULL) -#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; -static atomic_t ioc_count = ATOMIC_INIT(0); +static DEFINE_PER_CPU(unsigned long, ioc_count); 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) @@ -113,31 +81,14 @@ struct cfq_data { struct list_head idle_rr; unsigned int busy_queues; - /* - * non-ordered list of empty cfqq's - */ - struct list_head empty_list; - /* * cfqq lookup hash */ struct hlist_head *cfq_hash; - /* - * global crq hash for all queues - */ - struct hlist_head *crq_hash; - - unsigned int max_queued; - - mempool_t *crq_pool; - int rq_in_driver; int hw_tag; - /* - * schedule slice state info - */ /* * idle window management */ @@ -154,13 +105,10 @@ 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; @@ -183,23 +131,24 @@ struct cfq_queue { struct hlist_node cfq_hash; /* hash key */ unsigned int key; - /* on either rr or empty list of cfqd */ + /* member of the rr/busy/cur/idle cfqd list */ struct list_head cfq_list; /* 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 */ int allocated[2]; + /* pending metadata requests */ + int meta_pending; /* fifo list of requests in sort_list */ struct list_head fifo; unsigned long slice_start; unsigned long slice_end; unsigned long slice_left; - unsigned long service_last; /* number of requests that are on the dispatch list */ int on_dispatch[2]; @@ -212,18 +161,6 @@ 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, @@ -233,6 +170,7 @@ enum cfqq_state_flags { CFQ_CFQQ_FLAG_fifo_expire, CFQ_CFQQ_FLAG_idle_window, CFQ_CFQQ_FLAG_prio_changed, + CFQ_CFQQ_FLAG_queue_new, }; #define CFQ_CFQQ_FNS(name) \ @@ -257,71 +195,13 @@ CFQ_CFQQ_FNS(must_dispatch); CFQ_CFQQ_FNS(fifo_expire); CFQ_CFQQ_FNS(idle_window); CFQ_CFQQ_FNS(prio_changed); +CFQ_CFQQ_FNS(queue_new); #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); -#define process_sync(tsk) ((tsk)->flags & PF_SYNCWRITE) - -/* - * 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 @@ -341,19 +221,19 @@ static int cfq_queue_empty(request_queue_t *q) static inline pid_t cfq_queue_pid(struct task_struct *task, int rw) { - if (rw == READ || process_sync(task)) + if (rw == READ || rw == WRITE_SYNC) return task->pid; return CFQ_KEY_ASYNC; } /* - * 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; @@ -361,18 +241,22 @@ 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; + if (rq_is_meta(rq1) && !rq_is_meta(rq2)) + return rq1; + else if (rq_is_meta(rq2) && !rq_is_meta(rq1)) + return rq2; - s1 = crq1->request->sector; - s2 = crq2->request->sector; + s1 = rq1->sector; + s2 = rq2->sector; last = cfqd->last_sector; @@ -407,23 +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, @@ -432,50 +316,43 @@ 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; + struct rb_node *rbnext = rb_next(&last->rb_node); + struct rb_node *rbprev = rb_prev(&last->rb_node); + struct request *next = NULL, *prev = NULL; - if (!(rbnext = rb_next(&last->rb_node))) { - rbnext = rb_first(&cfqq->sort_list); - if (rbnext == &last->rb_node) - rbnext = 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) { struct cfq_data *cfqd = cfqq->cfqd; - struct list_head *list, *entry; + struct list_head *list; BUG_ON(!cfq_cfqq_on_rr(cfqq)); @@ -500,31 +377,26 @@ static void cfq_resort_rr_list(struct cfq_queue *cfqq, int preempted) } /* - * if queue was preempted, just add to front to be fair. busy_rr - * isn't sorted, but insert at the back for fairness. + * If this queue was preempted or is new (never been serviced), let + * it be added first for fairness but beind other new queues. + * Otherwise, just add to the back of the list. */ - if (preempted || list == &cfqd->busy_rr) { - if (preempted) - list = list->prev; + if (preempted || cfq_cfqq_queue_new(cfqq)) { + struct list_head *n = list; + struct cfq_queue *__cfqq; - list_add_tail(&cfqq->cfq_list, list); - return; - } + while (n->next != list) { + __cfqq = list_entry_cfqq(n->next); + if (!cfq_cfqq_queue_new(__cfqq)) + break; - /* - * sort by when queue was last serviced - */ - entry = list; - while ((entry = entry->prev) != list) { - struct cfq_queue *__cfqq = list_entry_cfqq(entry); + n = n->next; + } - if (!__cfqq->service_last) - break; - if (time_before(__cfqq->service_last, cfqq->service_last)) - break; + list = n; } - list_add(&cfqq->cfq_list, entry); + list_add_tail(&cfqq->cfq_list, list); } /* @@ -546,7 +418,7 @@ cfq_del_cfqq_rr(struct cfq_data *cfqd, struct cfq_queue *cfqq) { BUG_ON(!cfq_cfqq_on_rr(cfqq)); cfq_clear_cfqq_on_rr(cfqq); - list_move(&cfqq->cfq_list, &cfqd->empty_list); + list_del_init(&cfqq->cfq_list); BUG_ON(!cfqd->busy_queues); cfqd->busy_queues--; @@ -555,82 +427,43 @@ 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); - RB_CLEAR_COLOR(&crq->rb_node); + elv_rb_del(&cfqq->sort_list, rq); - if (cfq_cfqq_on_rr(cfqq) && RB_EMPTY(&cfqq->sort_list)) + 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) -{ - 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) +static void cfq_add_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; - 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 * @@ -639,27 +472,14 @@ 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; } @@ -689,11 +509,18 @@ 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); + + if (rq_is_meta(rq)) { + WARN_ON(!cfqq->meta_pending); + cfqq->meta_pending--; + } } static int @@ -701,39 +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); } } @@ -741,8 +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 */ @@ -784,13 +593,12 @@ __cfq_slice_expired(struct cfq_data *cfqd, struct cfq_queue *cfqq, if (cfq_cfqq_wait_request(cfqq)) del_timer(&cfqd->idle_slice_timer); - if (!preempted && !cfq_cfqq_dispatched(cfqq)) { - cfqq->service_last = now; + if (!preempted && !cfq_cfqq_dispatched(cfqq)) cfq_schedule_dispatch(cfqd); - } cfq_clear_cfqq_must_dispatch(cfqq); cfq_clear_cfqq_wait_request(cfqq); + cfq_clear_cfqq_queue_new(cfqq); /* * store what was left of this slice, if the queue idled out @@ -884,26 +692,25 @@ 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)) @@ -916,13 +723,15 @@ static struct cfq_queue *cfq_set_active_queue(struct cfq_data *cfqd) return cfqq; } +#define CIC_SEEKY(cic) ((cic)->seek_mean > (128 * 1024)) + static int cfq_arm_slice_timer(struct cfq_data *cfqd, struct cfq_queue *cfqq) { struct cfq_io_context *cic; unsigned long sl; - WARN_ON(!RB_EMPTY(&cfqq->sort_list)); + WARN_ON(!RB_EMPTY_ROOT(&cfqq->sort_list)); WARN_ON(cfqq != cfqd->active_queue); /* @@ -949,45 +758,46 @@ static int cfq_arm_slice_timer(struct cfq_data *cfqd, struct cfq_queue *cfqq) * fair distribution of slice time for a process doing back-to-back * seeks. so allow a little bit of time for him to submit a new rq */ - if (sample_valid(cic->seek_samples) && cic->seek_mean > 131072) - sl = 2; + if (sample_valid(cic->seek_samples) && CIC_SEEKY(cic)) + sl = min(sl, msecs_to_jiffies(2)); mod_timer(&cfqd->idle_slice_timer, jiffies + sl); 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 cfq_queue *cfqq = RQ_CFQQ(rq); + + cfq_remove_request(rq); + cfqq->on_dispatch[rq_is_sync(rq)]++; + elv_dispatch_sort(q, 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); + rq = list_entry(q->queue_head.prev, struct request, queuelist); + cfqd->last_sector = rq->sector + rq->nr_sectors; } /* * 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; @@ -1046,10 +856,12 @@ static struct cfq_queue *cfq_select_queue(struct cfq_data *cfqd) * if queue has requests, dispatch one. if not, check if * enough slice is left to wait for one */ - if (!RB_EMPTY(&cfqq->sort_list)) + if (!RB_EMPTY_ROOT(&cfqq->sort_list)) + goto keep_queue; + else if (cfq_cfqq_dispatched(cfqq)) { + cfqq = NULL; goto keep_queue; - else if (cfq_cfqq_class_sync(cfqq) && - time_before(now, cfqq->slice_end)) { + } else if (cfq_cfqq_class_sync(cfqq)) { if (cfq_arm_slice_timer(cfqd, cfqq)) return NULL; } @@ -1068,38 +880,37 @@ __cfq_dispatch_requests(struct cfq_data *cfqd, struct cfq_queue *cfqq, { int dispatched = 0; - BUG_ON(RB_EMPTY(&cfqq->sort_list)); + 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(&cfqq->sort_list)) + if (RB_EMPTY_ROOT(&cfqq->sort_list)) break; } while (dispatched < max_dispatch); /* - * if slice end isn't set yet, set it. if at least one request was - * sync, use the sync time slice value + * if slice end isn't set yet, set it. */ if (!cfqq->slice_end) cfq_set_prio_slice(cfqd, cfqq); @@ -1110,7 +921,8 @@ __cfq_dispatch_requests(struct cfq_data *cfqd, struct cfq_queue *cfqq, */ if ((!cfq_cfqq_sync(cfqq) && cfqd->dispatch_slice >= cfq_prio_to_maxrq(cfqd, cfqq)) || - cfq_class_idle(cfqq)) + cfq_class_idle(cfqq) || + !cfq_cfqq_idle_window(cfqq)) cfq_slice_expired(cfqd, 0); return dispatched; @@ -1119,17 +931,18 @@ __cfq_dispatch_requests(struct cfq_data *cfqd, struct cfq_queue *cfqq, static int cfq_forced_dispatch_cfqqs(struct list_head *list) { - int dispatched = 0; 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)); } + return dispatched; } @@ -1156,7 +969,8 @@ static int cfq_dispatch_requests(request_queue_t *q, int force) { struct cfq_data *cfqd = q->elevator->elevator_data; - struct cfq_queue *cfqq; + struct cfq_queue *cfqq, *prev_cfqq; + int dispatched; if (!cfqd->busy_queues) return 0; @@ -1164,10 +978,17 @@ cfq_dispatch_requests(request_queue_t *q, int force) if (unlikely(force)) return cfq_forced_dispatch(cfqd); - cfqq = cfq_select_queue(cfqd); - if (cfqq) { + dispatched = 0; + prev_cfqq = NULL; + while ((cfqq = cfq_select_queue(cfqd)) != NULL) { int max_dispatch; + /* + * Don't repeat dispatch from the previous queue. + */ + if (prev_cfqq == cfqq) + break; + cfq_clear_cfqq_must_dispatch(cfqq); cfq_clear_cfqq_wait_request(cfqq); del_timer(&cfqd->idle_slice_timer); @@ -1176,15 +997,24 @@ cfq_dispatch_requests(request_queue_t *q, int force) if (cfq_class_idle(cfqq)) max_dispatch = 1; - return __cfq_dispatch_requests(cfqd, cfqq, max_dispatch); + dispatched += __cfq_dispatch_requests(cfqd, cfqq, max_dispatch); + + /* + * If the dispatch cfqq has idling enabled and is still + * the active queue, break out. + */ + if (cfq_cfqq_idle_window(cfqq) && cfqd->active_queue) + break; + + prev_cfqq = cfqq; } - return 0; + return dispatched; } /* - * 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. */ @@ -1212,7 +1042,7 @@ static void cfq_put_queue(struct cfq_queue *cfqq) kmem_cache_free(cfq_pool, cfqq); } -static inline struct cfq_queue * +static struct cfq_queue * __cfq_find_cfq_hash(struct cfq_data *cfqd, unsigned int key, unsigned int prio, const int hashval) { @@ -1249,62 +1079,63 @@ static void cfq_free_io_context(struct io_context *ioc) freed++; } - if (atomic_sub_and_test(freed, &ioc_count) && ioc_gone) + elv_ioc_count_mod(ioc_count, -freed); + + if (ioc_gone && !elv_ioc_count_read(ioc_count)) complete(ioc_gone); } -static void cfq_trim(struct io_context *ioc) +static void cfq_exit_cfqq(struct cfq_data *cfqd, struct cfq_queue *cfqq) { - ioc->set_ioprio = NULL; - cfq_free_io_context(ioc); + if (unlikely(cfqq == cfqd->active_queue)) + __cfq_slice_expired(cfqd, cfqq, 0); + + cfq_put_queue(cfqq); } -/* - * Called with interrupts disabled - */ -static void cfq_exit_single_io_context(struct cfq_io_context *cic) +static void __cfq_exit_single_io_context(struct cfq_data *cfqd, + struct cfq_io_context *cic) { - struct cfq_data *cfqd = cic->key; - request_queue_t *q; - - if (!cfqd) - return; - - q = cfqd->queue; - - WARN_ON(!irqs_disabled()); - - spin_lock(q->queue_lock); + list_del_init(&cic->queue_list); + smp_wmb(); + cic->key = NULL; 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; + + if (cfqd) { + request_queue_t *q = cfqd->queue; + + spin_lock_irq(q->queue_lock); + __cfq_exit_single_io_context(cfqd, cic); + spin_unlock_irq(q->queue_lock); + } } static void cfq_exit_io_context(struct io_context *ioc) { struct cfq_io_context *__cic; - unsigned long flags; struct rb_node *n; /* * put the reference this task is holding to the various queues */ - spin_lock_irqsave(&cfq_exit_lock, flags); n = rb_first(&ioc->cic_root); while (n != NULL) { @@ -1313,28 +1144,21 @@ static void cfq_exit_io_context(struct io_context *ioc) cfq_exit_single_io_context(__cic); n = rb_next(n); } - - spin_unlock_irqrestore(&cfq_exit_lock, flags); } static struct cfq_io_context * cfq_alloc_io_context(struct cfq_data *cfqd, gfp_t gfp_mask) { - struct cfq_io_context *cic = kmem_cache_alloc(cfq_ioc_pool, gfp_mask); + struct cfq_io_context *cic; + cic = kmem_cache_alloc_node(cfq_ioc_pool, gfp_mask, cfqd->queue->node); if (cic) { - RB_CLEAR(&cic->rb_node); - cic->key = NULL; - cic->cfqq[ASYNC] = NULL; - cic->cfqq[SYNC] = NULL; + memset(cic, 0, sizeof(*cic)); cic->last_end_request = jiffies; - cic->ttime_total = 0; - cic->ttime_samples = 0; - cic->ttime_mean = 0; + INIT_LIST_HEAD(&cic->queue_list); cic->dtor = cfq_free_io_context; cic->exit = cfq_exit_io_context; - INIT_LIST_HEAD(&cic->queue_list); - atomic_inc(&ioc_count); + elv_ioc_count_inc(ioc_count); } return cic; @@ -1391,36 +1215,36 @@ static inline void changed_ioprio(struct cfq_io_context *cic) { struct cfq_data *cfqd = cic->key; struct cfq_queue *cfqq; - if (cfqd) { - spin_lock(cfqd->queue->queue_lock); - cfqq = cic->cfqq[ASYNC]; - if (cfqq) { - struct cfq_queue *new_cfqq; - new_cfqq = cfq_get_queue(cfqd, CFQ_KEY_ASYNC, - cic->ioc->task, GFP_ATOMIC); - if (new_cfqq) { - cic->cfqq[ASYNC] = new_cfqq; - cfq_put_queue(cfqq); - } - } - cfqq = cic->cfqq[SYNC]; - if (cfqq) { - cfq_mark_cfqq_prio_changed(cfqq); - cfq_init_prio_data(cfqq); + + if (unlikely(!cfqd)) + return; + + spin_lock(cfqd->queue->queue_lock); + + cfqq = cic->cfqq[ASYNC]; + if (cfqq) { + struct cfq_queue *new_cfqq; + new_cfqq = cfq_get_queue(cfqd, CFQ_KEY_ASYNC, cic->ioc->task, + GFP_ATOMIC); + if (new_cfqq) { + cic->cfqq[ASYNC] = new_cfqq; + cfq_put_queue(cfqq); } - spin_unlock(cfqd->queue->queue_lock); } + + cfqq = cic->cfqq[SYNC]; + if (cfqq) + cfq_mark_cfqq_prio_changed(cfqq); + + spin_unlock(cfqd->queue->queue_lock); } -/* - * callback from sys_ioprio_set, irqs are disabled - */ -static int cfq_ioc_set_ioprio(struct io_context *ioc, unsigned int ioprio) +static void cfq_ioc_set_ioprio(struct io_context *ioc) { struct cfq_io_context *cic; struct rb_node *n; - spin_lock(&cfq_exit_lock); + ioc->ioprio_changed = 0; n = rb_first(&ioc->cic_root); while (n != NULL) { @@ -1429,10 +1253,6 @@ static int cfq_ioc_set_ioprio(struct io_context *ioc, unsigned int ioprio) changed_ioprio(cic); n = rb_next(n); } - - spin_unlock(&cfq_exit_lock); - - return 0; } static struct cfq_queue * @@ -1452,12 +1272,18 @@ 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_node(cfq_pool, gfp_mask|__GFP_NOFAIL, cfqd->queue->node); spin_lock_irq(cfqd->queue->queue_lock); goto retry; } else { - cfqq = kmem_cache_alloc(cfq_pool, gfp_mask); + cfqq = kmem_cache_alloc_node(cfq_pool, gfp_mask, cfqd->queue->node); if (!cfqq) goto out; } @@ -1466,21 +1292,19 @@ retry: INIT_HLIST_NODE(&cfqq->cfq_hash); INIT_LIST_HEAD(&cfqq->cfq_list); - RB_CLEAR_ROOT(&cfqq->sort_list); INIT_LIST_HEAD(&cfqq->fifo); cfqq->key = key; hlist_add_head(&cfqq->cfq_hash, &cfqd->cfq_hash[hashval]); atomic_set(&cfqq->ref, 0); cfqq->cfqd = cfqd; - cfqq->service_last = 0; /* * set ->slice_left to allow preemption for a new process */ cfqq->slice_left = 2 * cfqd->cfq_slice_idle; - if (!cfqd->hw_tag) - cfq_mark_cfqq_idle_window(cfqq); + cfq_mark_cfqq_idle_window(cfqq); cfq_mark_cfqq_prio_changed(cfqq); + cfq_mark_cfqq_queue_new(cfqq); cfq_init_prio_data(cfqq); } @@ -1496,12 +1320,10 @@ out: static void cfq_drop_dead_cic(struct io_context *ioc, struct cfq_io_context *cic) { - spin_lock(&cfq_exit_lock); + WARN_ON(!list_empty(&cic->queue_list)); rb_erase(&cic->rb_node, &ioc->cic_root); - list_del_init(&cic->queue_list); - spin_unlock(&cfq_exit_lock); kmem_cache_free(cfq_ioc_pool, cic); - atomic_dec(&ioc_count); + elv_ioc_count_dec(ioc_count); } static struct cfq_io_context * @@ -1545,7 +1367,6 @@ cfq_cic_link(struct cfq_data *cfqd, struct io_context *ioc, cic->ioc = ioc; cic->key = cfqd; - ioc->set_ioprio = cfq_ioc_set_ioprio; restart: parent = NULL; p = &ioc->cic_root.rb_node; @@ -1555,7 +1376,7 @@ restart: /* ->key must be copied to avoid race with cfq_exit_queue() */ k = __cic->key; if (unlikely(!k)) { - cfq_drop_dead_cic(ioc, cic); + cfq_drop_dead_cic(ioc, __cic); goto restart; } @@ -1567,11 +1388,12 @@ restart: BUG(); } - spin_lock(&cfq_exit_lock); rb_link_node(&cic->rb_node, parent, p); rb_insert_color(&cic->rb_node, &ioc->cic_root); + + spin_lock_irq(cfqd->queue->queue_lock); list_add(&cic->queue_list, &cfqd->cic_list); - spin_unlock(&cfq_exit_lock); + spin_unlock_irq(cfqd->queue->queue_lock); } /* @@ -1587,7 +1409,7 @@ cfq_get_io_context(struct cfq_data *cfqd, gfp_t gfp_mask) might_sleep_if(gfp_mask & __GFP_WAIT); - ioc = get_io_context(gfp_mask); + ioc = get_io_context(gfp_mask, cfqd->queue->node); if (!ioc) return NULL; @@ -1601,6 +1423,10 @@ cfq_get_io_context(struct cfq_data *cfqd, gfp_t gfp_mask) cfq_cic_link(cfqd, ioc, cic); out: + smp_read_barrier_depends(); + if (unlikely(ioc->ioprio_changed)) + cfq_ioc_set_ioprio(ioc); + return cic; err: put_io_context(ioc); @@ -1634,15 +1460,15 @@ 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 @@ -1670,7 +1496,8 @@ cfq_update_idle_window(struct cfq_data *cfqd, struct cfq_queue *cfqq, { int enable_idle = cfq_cfqq_idle_window(cfqq); - if (!cic->ioc->task || !cfqd->cfq_slice_idle || cfqd->hw_tag) + if (!cic->ioc->task || !cfqd->cfq_slice_idle || + (cfqd->hw_tag && CIC_SEEKY(cic))) enable_idle = 0; else if (sample_valid(cic->ttime_samples)) { if (cic->ttime_mean > cfqd->cfq_slice_idle) @@ -1692,7 +1519,7 @@ 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; @@ -1700,7 +1527,7 @@ cfq_should_preempt(struct cfq_data *cfqd, struct cfq_queue *new_cfqq, return 0; if (!cfqq) - return 1; + return 0; if (cfq_class_idle(cfqq)) return 1; @@ -1711,7 +1538,17 @@ 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 the new request is sync, but the currently running queue is + * not, let the sync request have priority. + */ + if (rq_is_sync(rq) && !cfq_cfqq_sync(cfqq)) + return 1; + /* + * So both queues are sync. Let the new request get disk time if + * it's a metadata request and the current queue is doing regular IO. + */ + if (rq_is_meta(rq) && !cfqq->meta_pending) return 1; return 0; @@ -1723,51 +1560,45 @@ cfq_should_preempt(struct cfq_data *cfqd, struct cfq_queue *new_cfqq, */ static void cfq_preempt_queue(struct cfq_data *cfqd, struct cfq_queue *cfqq) { - struct cfq_queue *__cfqq, *next; - - list_for_each_entry_safe(__cfqq, next, &cfqd->cur_rr, cfq_list) - cfq_resort_rr_list(__cfqq, 1); + cfq_slice_expired(cfqd, 1); if (!cfqq->slice_left) cfqq->slice_left = cfq_prio_to_slice(cfqd, cfqq) / 2; - cfqq->slice_end = cfqq->slice_left + jiffies; - __cfq_slice_expired(cfqd, cfqq, 1); - __cfq_set_active_queue(cfqd, cfqq); -} - -/* - * should really be a ll_rw_blk.c helper - */ -static void cfq_start_queueing(struct cfq_data *cfqd, struct cfq_queue *cfqq) -{ - request_queue_t *q = cfqd->queue; + /* + * Put the new queue at the front of the of the current list, + * so we know that it will be selected next. + */ + BUG_ON(!cfq_cfqq_on_rr(cfqq)); + list_move(&cfqq->cfq_list, &cfqd->cur_rr); - if (!blk_queue_plugged(q)) - q->request_fn(q); - else - __generic_unplug_device(q); + cfqq->slice_end = cfqq->slice_left + jiffies; } /* - * 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; + struct cfq_io_context *cic = RQ_CIC(rq); - cfqq->next_crq = cfq_choose_req(cfqd, cfqq->next_crq, crq); + if (rq_is_meta(rq)) + cfqq->meta_pending++; - cic = crq->io_context; + /* + * 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. @@ -1775,17 +1606,17 @@ cfq_crq_enqueued(struct cfq_data *cfqd, struct cfq_queue *cfqq, if (cic == cfqd->active_cic && del_timer(&cfqd->idle_slice_timer)) { cfq_slice_expired(cfqd, 0); - cfq_start_queueing(cfqd, cfqq); + blk_start_queueing(cfqd->queue); } return; } 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) { /* @@ -1796,9 +1627,9 @@ cfq_crq_enqueued(struct cfq_data *cfqd, struct cfq_queue *cfqq, if (cfq_cfqq_wait_request(cfqq)) { cfq_mark_cfqq_must_dispatch(cfqq); del_timer(&cfqd->idle_slice_timer); - cfq_start_queueing(cfqd, cfqq); + blk_start_queueing(cfqd->queue); } - } 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 @@ -1806,34 +1637,32 @@ cfq_crq_enqueued(struct cfq_data *cfqd, struct cfq_queue *cfqq, */ cfq_preempt_queue(cfqd, cfqq); cfq_mark_cfqq_must_dispatch(cfqq); - cfq_start_queueing(cfqd, cfqq); + blk_start_queueing(cfqd->queue); } } 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; @@ -1846,40 +1675,24 @@ static void cfq_completed_request(request_queue_t *q, struct request *rq) if (!cfq_class_idle(cfqq)) cfqd->last_end_request = now; - if (!cfq_cfqq_dispatched(cfqq)) { - if (cfq_cfqq_on_rr(cfqq)) { - cfqq->service_last = now; - cfq_resort_rr_list(cfqq, 0); - } - cfq_schedule_dispatch(cfqd); - } - - if (cfq_crq_is_sync(crq)) - crq->io_context->last_end_request = now; -} - -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 (!cfq_cfqq_dispatched(cfqq) && cfq_cfqq_on_rr(cfqq)) + cfq_resort_rr_list(cfqq, 0); - if (rbnext) - return rb_entry_crq(rbnext)->request; + if (sync) + RQ_CIC(rq)->last_end_request = now; - return NULL; + /* + * If this is the active queue, check if it needs to be expired, + * or if we want to idle in case it has no pending requests. + */ + if (cfqd->active_queue == cfqq) { + if (time_after(now, cfqq->slice_end)) + cfq_slice_expired(cfqd, 0); + else if (sync && RB_EMPTY_ROOT(&cfqq->sort_list)) { + if (!cfq_arm_slice_timer(cfqd, cfqq)) + cfq_schedule_dispatch(cfqd); + } + } } /* @@ -1918,11 +1731,8 @@ 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 1 if ((cfq_cfqq_wait_request(cfqq) || cfq_cfqq_must_alloc(cfqq)) && !cfq_cfqq_must_alloc_slice(cfqq)) { cfq_mark_cfqq_must_alloc_slice(cfqq); @@ -1930,42 +1740,9 @@ __cfq_may_queue(struct cfq_data *cfqd, struct cfq_queue *cfqq, } return ELV_MQUEUE_MAY; -#else - if (!cfqq || task->flags & PF_MEMALLOC) - return ELV_MQUEUE_MAY; - if (!cfqq->allocated[rw] || cfq_cfqq_must_alloc(cfqq)) { - if (cfq_cfqq_wait_request(cfqq)) - return ELV_MQUEUE_MUST; - - /* - * only allow 1 ELV_MQUEUE_MUST per slice, otherwise we - * can quickly flood the queue with writes from a single task - */ - if (rw == READ || !cfq_cfqq_must_alloc_slice(cfqq)) { - cfq_mark_cfqq_must_alloc_slice(cfqq); - return ELV_MQUEUE_MUST; - } - - return ELV_MQUEUE_MAY; - } - if (cfq_class_idle(cfqq)) - return ELV_MQUEUE_NO; - if (cfqq->allocated[rw] >= cfqd->max_queued) { - struct io_context *ioc = get_io_context(GFP_ATOMIC); - int ret = ELV_MQUEUE_NO; - - if (ioc && ioc->nr_batch_requests) - ret = ELV_MQUEUE_MAY; - - put_io_context(ioc); - return ret; - } - - return ELV_MQUEUE_MAY; -#endif } -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; @@ -1982,51 +1759,30 @@ 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; - struct request_list *rl = &q->rq; - - if (cfqq->allocated[READ] <= cfqd->max_queued || cfqd->rq_starved) { - smp_mb(); - if (waitqueue_active(&rl->wait[READ])) - wake_up(&rl->wait[READ]); - } - - if (cfqq->allocated[WRITE] <= cfqd->max_queued || cfqd->rq_starved) { - smp_mb(); - 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); } } @@ -2035,8 +1791,7 @@ 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; @@ -2044,7 +1799,6 @@ 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; @@ -2068,42 +1822,18 @@ 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(&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; @@ -2112,27 +1842,10 @@ 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); + blk_start_queueing(q); spin_unlock_irqrestore(q->queue_lock, flags); } @@ -2160,16 +1873,13 @@ static void cfq_idle_slice_timer(unsigned long data) * only expire and reinvoke request handler, if there are * other queues with pending requests */ - if (!cfqd->busy_queues) { - cfqd->idle_slice_timer.expires = min(now + cfqd->cfq_slice_idle, cfqq->slice_end); - add_timer(&cfqd->idle_slice_timer); + if (!cfqd->busy_queues) goto out_cont; - } /* * not expired and it has a request pending, let it dispatch */ - if (!RB_EMPTY(&cfqq->sort_list)) { + if (!RB_EMPTY_ROOT(&cfqq->sort_list)) { cfq_mark_cfqq_must_dispatch(cfqq); goto out_kick; } @@ -2218,7 +1928,6 @@ static void cfq_exit_queue(elevator_t *e) cfq_shutdown_timer_wq(cfqd); - spin_lock(&cfq_exit_lock); spin_lock_irq(q->queue_lock); if (cfqd->active_queue) @@ -2228,37 +1937,26 @@ 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); - spin_unlock(&cfq_exit_lock); cfq_shutdown_timer_wq(cfqd); - mempool_destroy(cfqd->crq_pool); - kfree(cfqd->crq_hash); kfree(cfqd->cfq_hash); kfree(cfqd); } -static int cfq_init_queue(request_queue_t *q, elevator_t *e) +static void *cfq_init_queue(request_queue_t *q, elevator_t *e) { struct cfq_data *cfqd; int i; - cfqd = kmalloc(sizeof(*cfqd), GFP_KERNEL); + cfqd = kmalloc_node(sizeof(*cfqd), GFP_KERNEL, q->node); if (!cfqd) - return -ENOMEM; + return NULL; memset(cfqd, 0, sizeof(*cfqd)); @@ -2268,33 +1966,17 @@ static int cfq_init_queue(request_queue_t *q, elevator_t *e) INIT_LIST_HEAD(&cfqd->busy_rr); INIT_LIST_HEAD(&cfqd->cur_rr); INIT_LIST_HEAD(&cfqd->idle_rr); - 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); + cfqd->cfq_hash = kmalloc_node(sizeof(struct hlist_head) * CFQ_QHASH_ENTRIES, GFP_KERNEL, q->node); if (!cfqd->cfq_hash) - goto out_cfqhash; + goto out_free; - cfqd->crq_pool = mempool_create_slab_pool(BLKDEV_MIN_RQ, crq_pool); - if (!cfqd->crq_pool) - goto out_crqpool; - - 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]); - e->elevator_data = cfqd; - cfqd->queue = q; - cfqd->max_queued = q->nr_requests / 4; - q->nr_batching = cfq_queued; - init_timer(&cfqd->idle_slice_timer); cfqd->idle_slice_timer.function = cfq_idle_slice_timer; cfqd->idle_slice_timer.data = (unsigned long) cfqd; @@ -2305,7 +1987,6 @@ static int 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]; @@ -2316,20 +1997,14 @@ static int cfq_init_queue(request_queue_t *q, elevator_t *e) cfqd->cfq_slice_async_rq = cfq_slice_async_rq; cfqd->cfq_slice_idle = cfq_slice_idle; - return 0; -out_crqpool: - kfree(cfqd->cfq_hash); -out_cfqhash: - kfree(cfqd->crq_hash); -out_crqhash: + return cfqd; +out_free: kfree(cfqd); - return -ENOMEM; + 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) @@ -2338,11 +2013,6 @@ 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) @@ -2388,7 +2058,6 @@ 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); @@ -2416,7 +2085,6 @@ 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); @@ -2432,7 +2100,6 @@ 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), @@ -2455,14 +2122,14 @@ 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, .elevator_init_fn = cfq_init_queue, .elevator_exit_fn = cfq_exit_queue, - .trim = cfq_trim, + .trim = cfq_free_io_context, }, .elevator_attrs = cfq_attrs, .elevator_name = "cfq", @@ -2493,12 +2160,12 @@ static int __init cfq_init(void) static void __exit cfq_exit(void) { - DECLARE_COMPLETION(all_gone); + DECLARE_COMPLETION_ONSTACK(all_gone); elv_unregister(&iosched_cfq); ioc_gone = &all_gone; /* ioc_gone's update must be visible before reading ioc_count */ smp_wmb(); - if (atomic_read(&ioc_count)) + if (elv_ioc_count_read(ioc_count)) wait_for_completion(ioc_gone); synchronize_rcu(); cfq_slab_kill();