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block/cfq-iosched.c
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/* |
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* CFQ, or complete fairness queueing, disk scheduler. * * Based on ideas from a previously unfinished io * scheduler (round robin per-process disk scheduling) and Andrea Arcangeli. * * Copyright (C) 2003 Jens Axboe <axboe@suse.de> */ #include <linux/kernel.h> #include <linux/fs.h> #include <linux/blkdev.h> #include <linux/elevator.h> #include <linux/bio.h> #include <linux/config.h> #include <linux/module.h> #include <linux/slab.h> #include <linux/init.h> #include <linux/compiler.h> #include <linux/hash.h> #include <linux/rbtree.h> #include <linux/mempool.h> |
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#include <linux/ioprio.h> #include <linux/writeback.h> |
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/* * tunables */ static int cfq_quantum = 4; /* max queue in one round of service */ static int cfq_queued = 8; /* minimum rq allocate limit per-queue*/ |
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static int cfq_fifo_expire[2] = { HZ / 4, HZ / 8 }; |
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static int cfq_back_max = 16 * 1024; /* maximum backwards seek, in KiB */ static int cfq_back_penalty = 2; /* penalty of a backwards seek */ |
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static int cfq_slice_sync = HZ / 10; |
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static int cfq_slice_async = HZ / 25; |
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static int cfq_slice_async_rq = 2; |
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static int cfq_slice_idle = HZ / 100; |
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#define CFQ_IDLE_GRACE (HZ / 10) #define CFQ_SLICE_SCALE (5) #define CFQ_KEY_ASYNC (0) |
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#define CFQ_KEY_ANY (0xffff) |
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/* * disable queueing at the driver/hardware level */ |
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static int cfq_max_depth = 2; |
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/* * for the hash of cfqq inside the cfqd */ #define CFQ_QHASH_SHIFT 6 #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) |
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#define list_entry_fifo(ptr) list_entry((ptr), struct request, queuelist) |
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#define RQ_DATA(rq) (rq)->elevator_private /* * 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) |
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#define rb_entry_crq(node) rb_entry((node), struct cfq_rq, rb_node) #define rq_rb_key(rq) (rq)->sector |
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static kmem_cache_t *crq_pool; static kmem_cache_t *cfq_pool; static kmem_cache_t *cfq_ioc_pool; |
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#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) |
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#define ASYNC (0) #define SYNC (1) #define cfq_cfqq_dispatched(cfqq) \ ((cfqq)->on_dispatch[ASYNC] + (cfqq)->on_dispatch[SYNC]) #define cfq_cfqq_class_sync(cfqq) ((cfqq)->key != CFQ_KEY_ASYNC) #define cfq_cfqq_sync(cfqq) \ (cfq_cfqq_class_sync(cfqq) || (cfqq)->on_dispatch[SYNC]) |
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/* * Per block device queue structure */ |
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struct cfq_data { |
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atomic_t ref; request_queue_t *queue; /* * rr list of queues with requests and the count of them */ struct list_head rr_list[CFQ_PRIO_LISTS]; struct list_head busy_rr; struct list_head cur_rr; struct list_head idle_rr; unsigned int busy_queues; /* * non-ordered list of empty cfqq's */ |
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struct list_head empty_list; |
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/* * cfqq lookup hash */ |
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struct hlist_head *cfq_hash; |
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/* * global crq hash for all queues */ struct hlist_head *crq_hash; |
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unsigned int max_queued; |
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mempool_t *crq_pool; |
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int rq_in_driver; |
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/* * schedule slice state info */ /* * idle window management */ struct timer_list idle_slice_timer; struct work_struct unplug_work; |
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struct cfq_queue *active_queue; struct cfq_io_context *active_cic; int cur_prio, cur_end_prio; unsigned int dispatch_slice; struct timer_list idle_class_timer; |
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sector_t last_sector; |
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unsigned long last_end_request; |
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unsigned int rq_starved; |
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/* * tunables, see top of file */ unsigned int cfq_quantum; unsigned int cfq_queued; |
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unsigned int cfq_fifo_expire[2]; |
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unsigned int cfq_back_penalty; unsigned int cfq_back_max; |
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unsigned int cfq_slice[2]; unsigned int cfq_slice_async_rq; unsigned int cfq_slice_idle; unsigned int cfq_max_depth; |
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}; |
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/* * Per process-grouping structure */ |
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struct cfq_queue { /* reference count */ atomic_t ref; /* parent cfq_data */ struct cfq_data *cfqd; |
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/* cfqq lookup hash */ |
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struct hlist_node cfq_hash; /* hash key */ |
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unsigned int key; |
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/* on either rr or empty list of cfqd */ 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; /* requests queued in sort_list */ int queued[2]; /* currently allocated requests */ int allocated[2]; /* fifo list of requests in sort_list */ |
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struct list_head fifo; |
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unsigned long slice_start; unsigned long slice_end; unsigned long slice_left; unsigned long service_last; |
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/* number of requests that are on the dispatch list */ int on_dispatch[2]; |
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/* io prio of this group */ unsigned short ioprio, org_ioprio; unsigned short ioprio_class, org_ioprio_class; |
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/* various state flags, see below */ unsigned int flags; |
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}; 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; |
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unsigned int crq_flags; |
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}; |
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enum cfqq_state_flags { CFQ_CFQQ_FLAG_on_rr = 0, CFQ_CFQQ_FLAG_wait_request, CFQ_CFQQ_FLAG_must_alloc, CFQ_CFQQ_FLAG_must_alloc_slice, CFQ_CFQQ_FLAG_must_dispatch, CFQ_CFQQ_FLAG_fifo_expire, CFQ_CFQQ_FLAG_idle_window, CFQ_CFQQ_FLAG_prio_changed, CFQ_CFQQ_FLAG_expired, }; #define CFQ_CFQQ_FNS(name) \ static inline void cfq_mark_cfqq_##name(struct cfq_queue *cfqq) \ { \ cfqq->flags |= (1 << CFQ_CFQQ_FLAG_##name); \ } \ static inline void cfq_clear_cfqq_##name(struct cfq_queue *cfqq) \ { \ cfqq->flags &= ~(1 << CFQ_CFQQ_FLAG_##name); \ } \ static inline int cfq_cfqq_##name(const struct cfq_queue *cfqq) \ { \ return (cfqq->flags & (1 << CFQ_CFQQ_FLAG_##name)) != 0; \ } CFQ_CFQQ_FNS(on_rr); CFQ_CFQQ_FNS(wait_request); CFQ_CFQQ_FNS(must_alloc); CFQ_CFQQ_FNS(must_alloc_slice); CFQ_CFQQ_FNS(must_dispatch); CFQ_CFQQ_FNS(fifo_expire); CFQ_CFQQ_FNS(idle_window); CFQ_CFQQ_FNS(prio_changed); CFQ_CFQQ_FNS(expired); #undef CFQ_CFQQ_FNS enum cfq_rq_state_flags { |
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CFQ_CRQ_FLAG_is_sync = 0, |
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}; #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; \ } |
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CFQ_CRQ_FNS(is_sync); |
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#undef CFQ_CRQ_FNS static struct cfq_queue *cfq_find_cfq_hash(struct cfq_data *, unsigned int, unsigned short); |
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static void cfq_dispatch_insert(request_queue_t *, struct cfq_rq *); |
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static void cfq_put_cfqd(struct cfq_data *cfqd); |
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#define process_sync(tsk) ((tsk)->flags & PF_SYNCWRITE) |
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/* * 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); } |
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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)); |
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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; |
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if (!rq_mergeable(__rq)) { cfq_del_crq_hash(crq); continue; } if (rq_hash_key(__rq) == offset) return __rq; } return NULL; } |
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/* * scheduler run of queue, if there are requests pending and no one in the * driver that will restart queueing */ static inline void cfq_schedule_dispatch(struct cfq_data *cfqd) { |
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if (!cfqd->rq_in_driver && cfqd->busy_queues) |
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kblockd_schedule_work(&cfqd->unplug_work); } static int cfq_queue_empty(request_queue_t *q) { struct cfq_data *cfqd = q->elevator->elevator_data; |
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return !cfqd->busy_queues; |
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} |
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/* * Lifted from AS - choose which of crq1 and crq2 that is best served now. * We choose the request that is closest to the head right now. Distance * behind the head are 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) { sector_t last, s1, s2, d1 = 0, d2 = 0; int r1_wrap = 0, r2_wrap = 0; /* requests are behind the disk head */ unsigned long back_max; if (crq1 == NULL || crq1 == crq2) return crq2; if (crq2 == NULL) return crq1; |
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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)) |
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return crq2; |
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s1 = crq1->request->sector; s2 = crq2->request->sector; last = cfqd->last_sector; |
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/* * by definition, 1KiB is 2 sectors */ back_max = cfqd->cfq_back_max * 2; /* * Strict one way elevator _except_ in the case where we allow * short backward seeks which are biased as twice the cost of a * similar forward seek. */ if (s1 >= last) d1 = s1 - last; else if (s1 + back_max >= last) d1 = (last - s1) * cfqd->cfq_back_penalty; else r1_wrap = 1; if (s2 >= last) d2 = s2 - last; else if (s2 + back_max >= last) d2 = (last - s2) * cfqd->cfq_back_penalty; else r2_wrap = 1; /* Found required data */ if (!r1_wrap && r2_wrap) return crq1; else if (!r2_wrap && r1_wrap) return crq2; else if (r1_wrap && r2_wrap) { /* both behind the head */ if (s1 <= s2) return crq1; else return crq2; } /* Both requests in front of the head */ if (d1 < d2) return crq1; else if (d2 < d1) return crq2; else { if (s1 >= s2) return crq1; else return crq2; } } /* * 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) { struct cfq_rq *crq_next = NULL, *crq_prev = NULL; struct rb_node *rbnext, *rbprev; |
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if (!(rbnext = rb_next(&last->rb_node))) { |
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rbnext = rb_first(&cfqq->sort_list); |
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if (rbnext == &last->rb_node) rbnext = NULL; } |
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rbprev = rb_prev(&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); } static void cfq_update_next_crq(struct cfq_rq *crq) { struct cfq_queue *cfqq = crq->cfq_queue; if (cfqq->next_crq == crq) cfqq->next_crq = cfq_find_next_crq(cfqq->cfqd, cfqq, crq); } |
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static void cfq_resort_rr_list(struct cfq_queue *cfqq, int preempted) |
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{ |
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struct cfq_data *cfqd = cfqq->cfqd; struct list_head *list, *entry; |
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BUG_ON(!cfq_cfqq_on_rr(cfqq)); |
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list_del(&cfqq->cfq_list); |
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if (cfq_class_rt(cfqq)) list = &cfqd->cur_rr; else if (cfq_class_idle(cfqq)) list = &cfqd->idle_rr; else { /* * if cfqq has requests in flight, don't allow it to be * found in cfq_set_active_queue before it has finished them. * this is done to increase fairness between a process that * has lots of io pending vs one that only generates one * sporadically or synchronously */ |
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if (cfq_cfqq_dispatched(cfqq)) |
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list = &cfqd->busy_rr; else list = &cfqd->rr_list[cfqq->ioprio]; |
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} |
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/* * if queue was preempted, just add to front to be fair. busy_rr * isn't sorted. */ if (preempted || list == &cfqd->busy_rr) { list_add(&cfqq->cfq_list, list); |
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return; |
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} |
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/* |
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* sort by when queue was last serviced |
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*/ |
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entry = list; while ((entry = entry->prev) != list) { |
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struct cfq_queue *__cfqq = list_entry_cfqq(entry); |
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if (!__cfqq->service_last) break; if (time_before(__cfqq->service_last, cfqq->service_last)) |
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break; |
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} list_add(&cfqq->cfq_list, entry); } /* * add to busy list of queues for service, trying to be fair in ordering |
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* the pending list according to last request service |
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*/ static inline void |
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cfq_add_cfqq_rr(struct cfq_data *cfqd, struct cfq_queue *cfqq) |
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{ |
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BUG_ON(cfq_cfqq_on_rr(cfqq)); cfq_mark_cfqq_on_rr(cfqq); |
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cfqd->busy_queues++; |
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cfq_resort_rr_list(cfqq, 0); |
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} static inline void cfq_del_cfqq_rr(struct cfq_data *cfqd, struct cfq_queue *cfqq) { |
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BUG_ON(!cfq_cfqq_on_rr(cfqq)); cfq_clear_cfqq_on_rr(cfqq); |
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list_move(&cfqq->cfq_list, &cfqd->empty_list); |
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BUG_ON(!cfqd->busy_queues); cfqd->busy_queues--; } /* * rb tree support functions */ static inline void cfq_del_crq_rb(struct cfq_rq *crq) { struct cfq_queue *cfqq = crq->cfq_queue; |
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520 521 |
struct cfq_data *cfqd = cfqq->cfqd; const int sync = cfq_crq_is_sync(crq); |
1da177e4c Linux-2.6.12-rc2 |
522 |
|
b4878f245 [PATCH] 02/05: up... |
523 524 |
BUG_ON(!cfqq->queued[sync]); cfqq->queued[sync]--; |
1da177e4c Linux-2.6.12-rc2 |
525 |
|
b4878f245 [PATCH] 02/05: up... |
526 |
cfq_update_next_crq(crq); |
1da177e4c Linux-2.6.12-rc2 |
527 |
|
b4878f245 [PATCH] 02/05: up... |
528 529 |
rb_erase(&crq->rb_node, &cfqq->sort_list); RB_CLEAR_COLOR(&crq->rb_node); |
1da177e4c Linux-2.6.12-rc2 |
530 |
|
b4878f245 [PATCH] 02/05: up... |
531 532 |
if (cfq_cfqq_on_rr(cfqq) && RB_EMPTY(&cfqq->sort_list)) cfq_del_cfqq_rr(cfqd, cfqq); |
1da177e4c Linux-2.6.12-rc2 |
533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 |
} 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) { struct cfq_queue *cfqq = crq->cfq_queue; struct cfq_data *cfqd = cfqq->cfqd; struct request *rq = crq->request; struct cfq_rq *__alias; crq->rb_key = rq_rb_key(rq); |
3b18152c3 [PATCH] CFQ io sc... |
566 |
cfqq->queued[cfq_crq_is_sync(crq)]++; |
1da177e4c Linux-2.6.12-rc2 |
567 568 569 570 571 572 |
/* * 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) |
b4878f245 [PATCH] 02/05: up... |
573 |
cfq_dispatch_insert(cfqd->queue, __alias); |
1da177e4c Linux-2.6.12-rc2 |
574 575 |
rb_insert_color(&crq->rb_node, &cfqq->sort_list); |
3b18152c3 [PATCH] CFQ io sc... |
576 |
if (!cfq_cfqq_on_rr(cfqq)) |
b4878f245 [PATCH] 02/05: up... |
577 |
cfq_add_cfqq_rr(cfqd, cfqq); |
1da177e4c Linux-2.6.12-rc2 |
578 579 580 581 582 583 584 585 586 587 |
/* * 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) { |
b4878f245 [PATCH] 02/05: up... |
588 589 |
rb_erase(&crq->rb_node, &cfqq->sort_list); cfqq->queued[cfq_crq_is_sync(crq)]--; |
1da177e4c Linux-2.6.12-rc2 |
590 591 592 |
cfq_add_crq_rb(crq); } |
22e2c507c [PATCH] Update cf... |
593 |
static struct request *cfq_find_rq_rb(struct cfq_data *cfqd, sector_t sector) |
1da177e4c Linux-2.6.12-rc2 |
594 |
{ |
3b18152c3 [PATCH] CFQ io sc... |
595 |
struct cfq_queue *cfqq = cfq_find_cfq_hash(cfqd, current->pid, CFQ_KEY_ANY); |
1da177e4c Linux-2.6.12-rc2 |
596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 |
struct rb_node *n; if (!cfqq) goto out; n = cfqq->sort_list.rb_node; while (n) { struct cfq_rq *crq = rb_entry_crq(n); if (sector < crq->rb_key) n = n->rb_left; else if (sector > crq->rb_key) n = n->rb_right; else return crq->request; } out: return NULL; } |
b4878f245 [PATCH] 02/05: up... |
616 |
static void cfq_activate_request(request_queue_t *q, struct request *rq) |
1da177e4c Linux-2.6.12-rc2 |
617 |
{ |
22e2c507c [PATCH] Update cf... |
618 |
struct cfq_data *cfqd = q->elevator->elevator_data; |
3b18152c3 [PATCH] CFQ io sc... |
619 |
|
b4878f245 [PATCH] 02/05: up... |
620 |
cfqd->rq_in_driver++; |
1da177e4c Linux-2.6.12-rc2 |
621 |
} |
b4878f245 [PATCH] 02/05: up... |
622 |
static void cfq_deactivate_request(request_queue_t *q, struct request *rq) |
1da177e4c Linux-2.6.12-rc2 |
623 |
{ |
b4878f245 [PATCH] 02/05: up... |
624 625 626 627 |
struct cfq_data *cfqd = q->elevator->elevator_data; WARN_ON(!cfqd->rq_in_driver); cfqd->rq_in_driver--; |
1da177e4c Linux-2.6.12-rc2 |
628 |
} |
b4878f245 [PATCH] 02/05: up... |
629 |
static void cfq_remove_request(struct request *rq) |
1da177e4c Linux-2.6.12-rc2 |
630 631 |
{ struct cfq_rq *crq = RQ_DATA(rq); |
b4878f245 [PATCH] 02/05: up... |
632 633 |
list_del_init(&rq->queuelist); cfq_del_crq_rb(crq); |
98b11471d [PATCH] 04/05 rem... |
634 |
cfq_del_crq_hash(crq); |
1da177e4c Linux-2.6.12-rc2 |
635 636 637 638 639 640 641 642 |
} static int 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; |
1da177e4c Linux-2.6.12-rc2 |
643 |
__rq = cfq_find_rq_hash(cfqd, bio->bi_sector); |
22e2c507c [PATCH] Update cf... |
644 645 646 |
if (__rq && elv_rq_merge_ok(__rq, bio)) { ret = ELEVATOR_BACK_MERGE; goto out; |
1da177e4c Linux-2.6.12-rc2 |
647 648 649 |
} __rq = cfq_find_rq_rb(cfqd, bio->bi_sector + bio_sectors(bio)); |
22e2c507c [PATCH] Update cf... |
650 651 652 |
if (__rq && elv_rq_merge_ok(__rq, bio)) { ret = ELEVATOR_FRONT_MERGE; goto out; |
1da177e4c Linux-2.6.12-rc2 |
653 654 655 656 |
} return ELEVATOR_NO_MERGE; out: |
1da177e4c Linux-2.6.12-rc2 |
657 658 659 660 661 662 663 664 665 666 667 |
*req = __rq; return ret; } static void cfq_merged_request(request_queue_t *q, struct request *req) { 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); |
b4878f245 [PATCH] 02/05: up... |
668 |
if (rq_rb_key(req) != crq->rb_key) { |
1da177e4c Linux-2.6.12-rc2 |
669 670 671 672 673 |
struct cfq_queue *cfqq = crq->cfq_queue; cfq_update_next_crq(crq); cfq_reposition_crq_rb(cfqq, crq); } |
1da177e4c Linux-2.6.12-rc2 |
674 675 676 677 678 679 |
} static void cfq_merged_requests(request_queue_t *q, struct request *rq, struct request *next) { |
1da177e4c Linux-2.6.12-rc2 |
680 |
cfq_merged_request(q, rq); |
22e2c507c [PATCH] Update cf... |
681 682 683 684 685 686 |
/* * reposition in fifo if next is older than rq */ if (!list_empty(&rq->queuelist) && !list_empty(&next->queuelist) && time_before(next->start_time, rq->start_time)) list_move(&rq->queuelist, &next->queuelist); |
b4878f245 [PATCH] 02/05: up... |
687 |
cfq_remove_request(next); |
22e2c507c [PATCH] Update cf... |
688 689 690 691 692 693 694 695 696 697 698 699 700 701 |
} static inline void __cfq_set_active_queue(struct cfq_data *cfqd, struct cfq_queue *cfqq) { if (cfqq) { /* * stop potential idle class queues waiting service */ del_timer(&cfqd->idle_class_timer); cfqq->slice_start = jiffies; cfqq->slice_end = 0; cfqq->slice_left = 0; |
3b18152c3 [PATCH] CFQ io sc... |
702 703 704 |
cfq_clear_cfqq_must_alloc_slice(cfqq); cfq_clear_cfqq_fifo_expire(cfqq); cfq_clear_cfqq_expired(cfqq); |
22e2c507c [PATCH] Update cf... |
705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 |
} cfqd->active_queue = cfqq; } /* * 0 * 0,1 * 0,1,2 * 0,1,2,3 * 0,1,2,3,4 * 0,1,2,3,4,5 * 0,1,2,3,4,5,6 * 0,1,2,3,4,5,6,7 */ static int cfq_get_next_prio_level(struct cfq_data *cfqd) { int prio, wrap; prio = -1; wrap = 0; do { int p; for (p = cfqd->cur_prio; p <= cfqd->cur_end_prio; p++) { if (!list_empty(&cfqd->rr_list[p])) { prio = p; break; } } if (prio != -1) break; cfqd->cur_prio = 0; if (++cfqd->cur_end_prio == CFQ_PRIO_LISTS) { cfqd->cur_end_prio = 0; if (wrap) break; wrap = 1; |
1da177e4c Linux-2.6.12-rc2 |
744 |
} |
22e2c507c [PATCH] Update cf... |
745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 |
} while (1); if (unlikely(prio == -1)) return -1; BUG_ON(prio >= CFQ_PRIO_LISTS); list_splice_init(&cfqd->rr_list[prio], &cfqd->cur_rr); cfqd->cur_prio = prio + 1; if (cfqd->cur_prio > cfqd->cur_end_prio) { cfqd->cur_end_prio = cfqd->cur_prio; cfqd->cur_prio = 0; } if (cfqd->cur_end_prio == CFQ_PRIO_LISTS) { cfqd->cur_prio = 0; cfqd->cur_end_prio = 0; |
1da177e4c Linux-2.6.12-rc2 |
762 |
} |
22e2c507c [PATCH] Update cf... |
763 764 |
return prio; } |
3b18152c3 [PATCH] CFQ io sc... |
765 |
static struct cfq_queue *cfq_set_active_queue(struct cfq_data *cfqd) |
22e2c507c [PATCH] Update cf... |
766 |
{ |
3b18152c3 [PATCH] CFQ io sc... |
767 768 769 770 771 772 773 774 775 776 |
struct cfq_queue *cfqq; /* * if current queue is expired but not done with its requests yet, * wait for that to happen */ if ((cfqq = cfqd->active_queue) != NULL) { if (cfq_cfqq_expired(cfqq) && cfq_cfqq_dispatched(cfqq)) return NULL; } |
22e2c507c [PATCH] Update cf... |
777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 |
/* * 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) cfqq = list_entry_cfqq(cfqd->cur_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)) { unsigned long end = cfqd->last_end_request + CFQ_IDLE_GRACE; if (time_after_eq(jiffies, end)) cfqq = list_entry_cfqq(cfqd->idle_rr.next); else mod_timer(&cfqd->idle_class_timer, end); } __cfq_set_active_queue(cfqd, cfqq); |
3b18152c3 [PATCH] CFQ io sc... |
800 |
return cfqq; |
22e2c507c [PATCH] Update cf... |
801 802 803 804 805 |
} /* * current cfqq expired its slice (or was too idle), select new one */ |
3b18152c3 [PATCH] CFQ io sc... |
806 807 808 |
static void __cfq_slice_expired(struct cfq_data *cfqd, struct cfq_queue *cfqq, int preempted) |
22e2c507c [PATCH] Update cf... |
809 |
{ |
3b18152c3 [PATCH] CFQ io sc... |
810 |
unsigned long now = jiffies; |
22e2c507c [PATCH] Update cf... |
811 |
|
3b18152c3 [PATCH] CFQ io sc... |
812 813 |
if (cfq_cfqq_wait_request(cfqq)) del_timer(&cfqd->idle_slice_timer); |
22e2c507c [PATCH] Update cf... |
814 |
|
3b18152c3 [PATCH] CFQ io sc... |
815 816 |
if (!preempted && !cfq_cfqq_dispatched(cfqq)) cfqq->service_last = now; |
22e2c507c [PATCH] Update cf... |
817 |
|
3b18152c3 [PATCH] CFQ io sc... |
818 819 |
cfq_clear_cfqq_must_dispatch(cfqq); cfq_clear_cfqq_wait_request(cfqq); |
22e2c507c [PATCH] Update cf... |
820 |
|
3b18152c3 [PATCH] CFQ io sc... |
821 822 823 824 |
/* * store what was left of this slice, if the queue idled out * or was preempted */ |
b740d98f5 [BLOCK] cfq-iosch... |
825 826 |
if (time_after(cfqq->slice_end, now)) cfqq->slice_left = cfqq->slice_end - now; |
3b18152c3 [PATCH] CFQ io sc... |
827 828 |
else cfqq->slice_left = 0; |
22e2c507c [PATCH] Update cf... |
829 |
|
3b18152c3 [PATCH] CFQ io sc... |
830 831 |
if (cfq_cfqq_on_rr(cfqq)) cfq_resort_rr_list(cfqq, preempted); |
22e2c507c [PATCH] Update cf... |
832 |
|
3b18152c3 [PATCH] CFQ io sc... |
833 |
if (cfqq == cfqd->active_queue) |
22e2c507c [PATCH] Update cf... |
834 |
cfqd->active_queue = NULL; |
3b18152c3 [PATCH] CFQ io sc... |
835 836 837 |
if (cfqd->active_cic) { put_io_context(cfqd->active_cic->ioc); cfqd->active_cic = NULL; |
22e2c507c [PATCH] Update cf... |
838 839 840 841 |
} cfqd->dispatch_slice = 0; } |
3b18152c3 [PATCH] CFQ io sc... |
842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 |
static inline void cfq_slice_expired(struct cfq_data *cfqd, int preempted) { struct cfq_queue *cfqq = cfqd->active_queue; if (cfqq) { /* * use deferred expiry, if there are requests in progress as * not to disturb the slice of the next queue */ if (cfq_cfqq_dispatched(cfqq)) cfq_mark_cfqq_expired(cfqq); else __cfq_slice_expired(cfqd, cfqq, preempted); } } |
22e2c507c [PATCH] Update cf... |
857 858 859 860 861 862 863 864 865 866 867 |
static int cfq_arm_slice_timer(struct cfq_data *cfqd, struct cfq_queue *cfqq) { WARN_ON(!RB_EMPTY(&cfqq->sort_list)); WARN_ON(cfqq != cfqd->active_queue); /* * idle is disabled, either manually or by past process history */ if (!cfqd->cfq_slice_idle) return 0; |
3b18152c3 [PATCH] CFQ io sc... |
868 |
if (!cfq_cfqq_idle_window(cfqq)) |
22e2c507c [PATCH] Update cf... |
869 870 871 872 873 874 |
return 0; /* * task has exited, don't wait */ if (cfqd->active_cic && !cfqd->active_cic->ioc->task) return 0; |
3b18152c3 [PATCH] CFQ io sc... |
875 876 |
cfq_mark_cfqq_must_dispatch(cfqq); cfq_mark_cfqq_wait_request(cfqq); |
22e2c507c [PATCH] Update cf... |
877 878 |
if (!timer_pending(&cfqd->idle_slice_timer)) { |
3b18152c3 [PATCH] CFQ io sc... |
879 |
unsigned long slice_left = min(cfqq->slice_end - 1, (unsigned long) cfqd->cfq_slice_idle); |
22e2c507c [PATCH] Update cf... |
880 |
|
3b18152c3 [PATCH] CFQ io sc... |
881 |
cfqd->idle_slice_timer.expires = jiffies + slice_left; |
22e2c507c [PATCH] Update cf... |
882 883 884 885 |
add_timer(&cfqd->idle_slice_timer); } return 1; |
1da177e4c Linux-2.6.12-rc2 |
886 |
} |
b4878f245 [PATCH] 02/05: up... |
887 |
static void cfq_dispatch_insert(request_queue_t *q, struct cfq_rq *crq) |
1da177e4c Linux-2.6.12-rc2 |
888 889 890 |
{ struct cfq_data *cfqd = q->elevator->elevator_data; struct cfq_queue *cfqq = crq->cfq_queue; |
22e2c507c [PATCH] Update cf... |
891 892 |
cfqq->next_crq = cfq_find_next_crq(cfqd, cfqq, crq); |
b4878f245 [PATCH] 02/05: up... |
893 |
cfq_remove_request(crq->request); |
3b18152c3 [PATCH] CFQ io sc... |
894 |
cfqq->on_dispatch[cfq_crq_is_sync(crq)]++; |
b4878f245 [PATCH] 02/05: up... |
895 |
elv_dispatch_sort(q, crq->request); |
1da177e4c Linux-2.6.12-rc2 |
896 897 898 899 900 901 902 903 |
} /* * return expired entry, or NULL to just start from scratch in rbtree */ static inline struct cfq_rq *cfq_check_fifo(struct cfq_queue *cfqq) { struct cfq_data *cfqd = cfqq->cfqd; |
22e2c507c [PATCH] Update cf... |
904 |
struct request *rq; |
1da177e4c Linux-2.6.12-rc2 |
905 |
struct cfq_rq *crq; |
3b18152c3 [PATCH] CFQ io sc... |
906 |
if (cfq_cfqq_fifo_expire(cfqq)) |
1da177e4c Linux-2.6.12-rc2 |
907 |
return NULL; |
22e2c507c [PATCH] Update cf... |
908 |
if (!list_empty(&cfqq->fifo)) { |
3b18152c3 [PATCH] CFQ io sc... |
909 |
int fifo = cfq_cfqq_class_sync(cfqq); |
1da177e4c Linux-2.6.12-rc2 |
910 |
|
22e2c507c [PATCH] Update cf... |
911 912 913 |
crq = RQ_DATA(list_entry_fifo(cfqq->fifo.next)); rq = crq->request; if (time_after(jiffies, rq->start_time + cfqd->cfq_fifo_expire[fifo])) { |
3b18152c3 [PATCH] CFQ io sc... |
914 |
cfq_mark_cfqq_fifo_expire(cfqq); |
22e2c507c [PATCH] Update cf... |
915 916 |
return crq; } |
1da177e4c Linux-2.6.12-rc2 |
917 918 919 920 921 922 |
} return NULL; } /* |
3b18152c3 [PATCH] CFQ io sc... |
923 924 925 |
* Scale schedule slice based on io priority. Use the sync time slice only * if a queue is marked sync and has sync io queued. A sync queue with async * io only, should not get full sync slice length. |
1da177e4c Linux-2.6.12-rc2 |
926 |
*/ |
22e2c507c [PATCH] Update cf... |
927 928 929 930 931 932 933 934 935 |
static inline int cfq_prio_to_slice(struct cfq_data *cfqd, struct cfq_queue *cfqq) { const int base_slice = cfqd->cfq_slice[cfq_cfqq_sync(cfqq)]; WARN_ON(cfqq->ioprio >= IOPRIO_BE_NR); return base_slice + (base_slice/CFQ_SLICE_SCALE * (4 - cfqq->ioprio)); } |
1da177e4c Linux-2.6.12-rc2 |
936 |
static inline void |
22e2c507c [PATCH] Update cf... |
937 |
cfq_set_prio_slice(struct cfq_data *cfqd, struct cfq_queue *cfqq) |
1da177e4c Linux-2.6.12-rc2 |
938 |
{ |
22e2c507c [PATCH] Update cf... |
939 940 |
cfqq->slice_end = cfq_prio_to_slice(cfqd, cfqq) + jiffies; } |
1da177e4c Linux-2.6.12-rc2 |
941 |
|
22e2c507c [PATCH] Update cf... |
942 943 944 945 |
static inline int cfq_prio_to_maxrq(struct cfq_data *cfqd, struct cfq_queue *cfqq) { const int base_rq = cfqd->cfq_slice_async_rq; |
1da177e4c Linux-2.6.12-rc2 |
946 |
|
22e2c507c [PATCH] Update cf... |
947 |
WARN_ON(cfqq->ioprio >= IOPRIO_BE_NR); |
1da177e4c Linux-2.6.12-rc2 |
948 |
|
22e2c507c [PATCH] Update cf... |
949 |
return 2 * (base_rq + base_rq * (CFQ_PRIO_LISTS - 1 - cfqq->ioprio)); |
1da177e4c Linux-2.6.12-rc2 |
950 |
} |
22e2c507c [PATCH] Update cf... |
951 952 953 |
/* * get next queue for service */ |
1b5ed5e1f [BLOCK] cfq-iosch... |
954 |
static struct cfq_queue *cfq_select_queue(struct cfq_data *cfqd) |
1da177e4c Linux-2.6.12-rc2 |
955 |
{ |
22e2c507c [PATCH] Update cf... |
956 |
unsigned long now = jiffies; |
1da177e4c Linux-2.6.12-rc2 |
957 |
struct cfq_queue *cfqq; |
1da177e4c Linux-2.6.12-rc2 |
958 |
|
22e2c507c [PATCH] Update cf... |
959 960 961 |
cfqq = cfqd->active_queue; if (!cfqq) goto new_queue; |
1da177e4c Linux-2.6.12-rc2 |
962 |
|
3b18152c3 [PATCH] CFQ io sc... |
963 964 |
if (cfq_cfqq_expired(cfqq)) goto new_queue; |
22e2c507c [PATCH] Update cf... |
965 966 967 |
/* * slice has expired */ |
3b18152c3 [PATCH] CFQ io sc... |
968 969 |
if (!cfq_cfqq_must_dispatch(cfqq) && time_after(now, cfqq->slice_end)) goto expire; |
1da177e4c Linux-2.6.12-rc2 |
970 |
|
22e2c507c [PATCH] Update cf... |
971 972 973 974 975 976 |
/* * if queue has requests, dispatch one. if not, check if * enough slice is left to wait for one */ if (!RB_EMPTY(&cfqq->sort_list)) goto keep_queue; |
1b5ed5e1f [BLOCK] cfq-iosch... |
977 |
else if (cfq_cfqq_class_sync(cfqq) && |
22e2c507c [PATCH] Update cf... |
978 979 980 981 |
time_before(now, cfqq->slice_end)) { if (cfq_arm_slice_timer(cfqd, cfqq)) return NULL; } |
3b18152c3 [PATCH] CFQ io sc... |
982 |
expire: |
22e2c507c [PATCH] Update cf... |
983 |
cfq_slice_expired(cfqd, 0); |
3b18152c3 [PATCH] CFQ io sc... |
984 985 |
new_queue: cfqq = cfq_set_active_queue(cfqd); |
22e2c507c [PATCH] Update cf... |
986 |
keep_queue: |
3b18152c3 [PATCH] CFQ io sc... |
987 |
return cfqq; |
22e2c507c [PATCH] Update cf... |
988 989 990 991 992 993 994 995 996 997 998 999 |
} static int __cfq_dispatch_requests(struct cfq_data *cfqd, struct cfq_queue *cfqq, int max_dispatch) { int dispatched = 0; BUG_ON(RB_EMPTY(&cfqq->sort_list)); do { struct cfq_rq *crq; |
1da177e4c Linux-2.6.12-rc2 |
1000 1001 |
/* |
22e2c507c [PATCH] Update cf... |
1002 |
* follow expired path, else get first next available |
1da177e4c Linux-2.6.12-rc2 |
1003 |
*/ |
22e2c507c [PATCH] Update cf... |
1004 1005 1006 1007 1008 1009 |
if ((crq = cfq_check_fifo(cfqq)) == NULL) crq = cfqq->next_crq; /* * finally, insert request into driver dispatch list */ |
b4878f245 [PATCH] 02/05: up... |
1010 |
cfq_dispatch_insert(cfqd->queue, crq); |
1da177e4c Linux-2.6.12-rc2 |
1011 |
|
22e2c507c [PATCH] Update cf... |
1012 1013 |
cfqd->dispatch_slice++; dispatched++; |
1da177e4c Linux-2.6.12-rc2 |
1014 |
|
22e2c507c [PATCH] Update cf... |
1015 1016 1017 1018 |
if (!cfqd->active_cic) { atomic_inc(&crq->io_context->ioc->refcount); cfqd->active_cic = crq->io_context; } |
1da177e4c Linux-2.6.12-rc2 |
1019 |
|
22e2c507c [PATCH] Update cf... |
1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 |
if (RB_EMPTY(&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 (!cfqq->slice_end) cfq_set_prio_slice(cfqd, cfqq); /* * expire an async queue immediately if it has used up its slice. idle * queue always expire after 1 dispatch round. */ if ((!cfq_cfqq_sync(cfqq) && cfqd->dispatch_slice >= cfq_prio_to_maxrq(cfqd, cfqq)) || cfq_class_idle(cfqq)) cfq_slice_expired(cfqd, 0); return dispatched; } static int |
1b5ed5e1f [BLOCK] cfq-iosch... |
1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 |
cfq_forced_dispatch_cfqqs(struct list_head *list) { int dispatched = 0; struct cfq_queue *cfqq, *next; struct cfq_rq *crq; list_for_each_entry_safe(cfqq, next, list, cfq_list) { while ((crq = cfqq->next_crq)) { cfq_dispatch_insert(cfqq->cfqd->queue, crq); dispatched++; } BUG_ON(!list_empty(&cfqq->fifo)); } return dispatched; } static int cfq_forced_dispatch(struct cfq_data *cfqd) { int i, dispatched = 0; for (i = 0; i < CFQ_PRIO_LISTS; i++) dispatched += cfq_forced_dispatch_cfqqs(&cfqd->rr_list[i]); dispatched += cfq_forced_dispatch_cfqqs(&cfqd->busy_rr); dispatched += cfq_forced_dispatch_cfqqs(&cfqd->cur_rr); dispatched += cfq_forced_dispatch_cfqqs(&cfqd->idle_rr); cfq_slice_expired(cfqd, 0); BUG_ON(cfqd->busy_queues); return dispatched; } static int |
b4878f245 [PATCH] 02/05: up... |
1081 |
cfq_dispatch_requests(request_queue_t *q, int force) |
22e2c507c [PATCH] Update cf... |
1082 1083 1084 1085 1086 1087 |
{ struct cfq_data *cfqd = q->elevator->elevator_data; struct cfq_queue *cfqq; if (!cfqd->busy_queues) return 0; |
1b5ed5e1f [BLOCK] cfq-iosch... |
1088 1089 1090 1091 |
if (unlikely(force)) return cfq_forced_dispatch(cfqd); cfqq = cfq_select_queue(cfqd); |
22e2c507c [PATCH] Update cf... |
1092 |
if (cfqq) { |
b4878f245 [PATCH] 02/05: up... |
1093 1094 1095 1096 1097 1098 1099 1100 |
int max_dispatch; /* * if idle window is disabled, allow queue buildup */ if (!cfq_cfqq_idle_window(cfqq) && cfqd->rq_in_driver >= cfqd->cfq_max_depth) return 0; |
3b18152c3 [PATCH] CFQ io sc... |
1101 1102 |
cfq_clear_cfqq_must_dispatch(cfqq); cfq_clear_cfqq_wait_request(cfqq); |
22e2c507c [PATCH] Update cf... |
1103 |
del_timer(&cfqd->idle_slice_timer); |
1b5ed5e1f [BLOCK] cfq-iosch... |
1104 1105 1106 |
max_dispatch = cfqd->cfq_quantum; if (cfq_class_idle(cfqq)) max_dispatch = 1; |
1da177e4c Linux-2.6.12-rc2 |
1107 |
|
22e2c507c [PATCH] Update cf... |
1108 |
return __cfq_dispatch_requests(cfqd, cfqq, max_dispatch); |
1da177e4c Linux-2.6.12-rc2 |
1109 |
} |
22e2c507c [PATCH] Update cf... |
1110 |
return 0; |
1da177e4c Linux-2.6.12-rc2 |
1111 |
} |
1da177e4c Linux-2.6.12-rc2 |
1112 1113 1114 1115 1116 1117 1118 1119 |
/* * 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. * * queue lock must be held here. */ static void cfq_put_queue(struct cfq_queue *cfqq) { |
22e2c507c [PATCH] Update cf... |
1120 1121 1122 |
struct cfq_data *cfqd = cfqq->cfqd; BUG_ON(atomic_read(&cfqq->ref) <= 0); |
1da177e4c Linux-2.6.12-rc2 |
1123 1124 1125 1126 1127 |
if (!atomic_dec_and_test(&cfqq->ref)) return; BUG_ON(rb_first(&cfqq->sort_list)); |
22e2c507c [PATCH] Update cf... |
1128 |
BUG_ON(cfqq->allocated[READ] + cfqq->allocated[WRITE]); |
3b18152c3 [PATCH] CFQ io sc... |
1129 |
BUG_ON(cfq_cfqq_on_rr(cfqq)); |
1da177e4c Linux-2.6.12-rc2 |
1130 |
|
22e2c507c [PATCH] Update cf... |
1131 |
if (unlikely(cfqd->active_queue == cfqq)) { |
3b18152c3 [PATCH] CFQ io sc... |
1132 1133 |
__cfq_slice_expired(cfqd, cfqq, 0); cfq_schedule_dispatch(cfqd); |
22e2c507c [PATCH] Update cf... |
1134 |
} |
1da177e4c Linux-2.6.12-rc2 |
1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 |
cfq_put_cfqd(cfqq->cfqd); /* * it's on the empty list and still hashed */ list_del(&cfqq->cfq_list); hlist_del(&cfqq->cfq_hash); kmem_cache_free(cfq_pool, cfqq); } static inline struct cfq_queue * |
3b18152c3 [PATCH] CFQ io sc... |
1146 1147 |
__cfq_find_cfq_hash(struct cfq_data *cfqd, unsigned int key, unsigned int prio, const int hashval) |
1da177e4c Linux-2.6.12-rc2 |
1148 1149 1150 1151 1152 1153 |
{ struct hlist_head *hash_list = &cfqd->cfq_hash[hashval]; struct hlist_node *entry, *next; hlist_for_each_safe(entry, next, hash_list) { struct cfq_queue *__cfqq = list_entry_qhash(entry); |
3b18152c3 [PATCH] CFQ io sc... |
1154 |
const unsigned short __p = IOPRIO_PRIO_VALUE(__cfqq->ioprio_class, __cfqq->ioprio); |
1da177e4c Linux-2.6.12-rc2 |
1155 |
|
3b18152c3 [PATCH] CFQ io sc... |
1156 |
if (__cfqq->key == key && (__p == prio || prio == CFQ_KEY_ANY)) |
1da177e4c Linux-2.6.12-rc2 |
1157 1158 1159 1160 1161 1162 1163 |
return __cfqq; } return NULL; } static struct cfq_queue * |
3b18152c3 [PATCH] CFQ io sc... |
1164 |
cfq_find_cfq_hash(struct cfq_data *cfqd, unsigned int key, unsigned short prio) |
1da177e4c Linux-2.6.12-rc2 |
1165 |
{ |
3b18152c3 [PATCH] CFQ io sc... |
1166 |
return __cfq_find_cfq_hash(cfqd, key, prio, hash_long(key, CFQ_QHASH_SHIFT)); |
1da177e4c Linux-2.6.12-rc2 |
1167 |
} |
22e2c507c [PATCH] Update cf... |
1168 |
static void cfq_free_io_context(struct cfq_io_context *cic) |
1da177e4c Linux-2.6.12-rc2 |
1169 |
{ |
22e2c507c [PATCH] Update cf... |
1170 1171 |
struct cfq_io_context *__cic; struct list_head *entry, *next; |
1da177e4c Linux-2.6.12-rc2 |
1172 |
|
22e2c507c [PATCH] Update cf... |
1173 1174 1175 |
list_for_each_safe(entry, next, &cic->list) { __cic = list_entry(entry, struct cfq_io_context, list); kmem_cache_free(cfq_ioc_pool, __cic); |
1da177e4c Linux-2.6.12-rc2 |
1176 |
} |
22e2c507c [PATCH] Update cf... |
1177 |
kmem_cache_free(cfq_ioc_pool, cic); |
1da177e4c Linux-2.6.12-rc2 |
1178 |
} |
22e2c507c [PATCH] Update cf... |
1179 1180 1181 1182 |
/* * Called with interrupts disabled */ static void cfq_exit_single_io_context(struct cfq_io_context *cic) |
1da177e4c Linux-2.6.12-rc2 |
1183 |
{ |
22e2c507c [PATCH] Update cf... |
1184 1185 1186 1187 1188 1189 1190 1191 |
struct cfq_data *cfqd = cic->cfqq->cfqd; request_queue_t *q = cfqd->queue; WARN_ON(!irqs_disabled()); spin_lock(q->queue_lock); if (unlikely(cic->cfqq == cfqd->active_queue)) { |
3b18152c3 [PATCH] CFQ io sc... |
1192 1193 |
__cfq_slice_expired(cfqd, cic->cfqq, 0); cfq_schedule_dispatch(cfqd); |
22e2c507c [PATCH] Update cf... |
1194 1195 1196 1197 1198 |
} cfq_put_queue(cic->cfqq); cic->cfqq = NULL; spin_unlock(q->queue_lock); |
1da177e4c Linux-2.6.12-rc2 |
1199 1200 1201 |
} /* |
22e2c507c [PATCH] Update cf... |
1202 1203 |
* Another task may update the task cic list, if it is doing a queue lookup * on its behalf. cfq_cic_lock excludes such concurrent updates |
1da177e4c Linux-2.6.12-rc2 |
1204 1205 1206 |
*/ static void cfq_exit_io_context(struct cfq_io_context *cic) { |
22e2c507c [PATCH] Update cf... |
1207 1208 |
struct cfq_io_context *__cic; struct list_head *entry; |
1da177e4c Linux-2.6.12-rc2 |
1209 |
unsigned long flags; |
22e2c507c [PATCH] Update cf... |
1210 |
local_irq_save(flags); |
1da177e4c Linux-2.6.12-rc2 |
1211 1212 1213 |
/* * put the reference this task is holding to the various queues */ |
22e2c507c [PATCH] Update cf... |
1214 |
list_for_each(entry, &cic->list) { |
1da177e4c Linux-2.6.12-rc2 |
1215 |
__cic = list_entry(entry, struct cfq_io_context, list); |
22e2c507c [PATCH] Update cf... |
1216 |
cfq_exit_single_io_context(__cic); |
1da177e4c Linux-2.6.12-rc2 |
1217 |
} |
22e2c507c [PATCH] Update cf... |
1218 1219 |
cfq_exit_single_io_context(cic); local_irq_restore(flags); |
1da177e4c Linux-2.6.12-rc2 |
1220 |
} |
22e2c507c [PATCH] Update cf... |
1221 |
static struct cfq_io_context * |
8267e268e [PATCH] gfp_t: bl... |
1222 |
cfq_alloc_io_context(struct cfq_data *cfqd, gfp_t gfp_mask) |
1da177e4c Linux-2.6.12-rc2 |
1223 |
{ |
22e2c507c [PATCH] Update cf... |
1224 |
struct cfq_io_context *cic = kmem_cache_alloc(cfq_ioc_pool, gfp_mask); |
1da177e4c Linux-2.6.12-rc2 |
1225 1226 |
if (cic) { |
1da177e4c Linux-2.6.12-rc2 |
1227 1228 |
INIT_LIST_HEAD(&cic->list); cic->cfqq = NULL; |
22e2c507c [PATCH] Update cf... |
1229 1230 1231 1232 1233 1234 1235 |
cic->key = NULL; cic->last_end_request = jiffies; cic->ttime_total = 0; cic->ttime_samples = 0; cic->ttime_mean = 0; cic->dtor = cfq_free_io_context; cic->exit = cfq_exit_io_context; |
1da177e4c Linux-2.6.12-rc2 |
1236 1237 1238 1239 |
} return cic; } |
22e2c507c [PATCH] Update cf... |
1240 1241 1242 1243 |
static void cfq_init_prio_data(struct cfq_queue *cfqq) { struct task_struct *tsk = current; int ioprio_class; |
3b18152c3 [PATCH] CFQ io sc... |
1244 |
if (!cfq_cfqq_prio_changed(cfqq)) |
22e2c507c [PATCH] Update cf... |
1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 |
return; ioprio_class = IOPRIO_PRIO_CLASS(tsk->ioprio); switch (ioprio_class) { default: printk(KERN_ERR "cfq: bad prio %x ", ioprio_class); case IOPRIO_CLASS_NONE: /* * no prio set, place us in the middle of the BE classes */ cfqq->ioprio = task_nice_ioprio(tsk); cfqq->ioprio_class = IOPRIO_CLASS_BE; break; case IOPRIO_CLASS_RT: cfqq->ioprio = task_ioprio(tsk); cfqq->ioprio_class = IOPRIO_CLASS_RT; break; case IOPRIO_CLASS_BE: cfqq->ioprio = task_ioprio(tsk); cfqq->ioprio_class = IOPRIO_CLASS_BE; break; case IOPRIO_CLASS_IDLE: cfqq->ioprio_class = IOPRIO_CLASS_IDLE; cfqq->ioprio = 7; |
3b18152c3 [PATCH] CFQ io sc... |
1270 |
cfq_clear_cfqq_idle_window(cfqq); |
22e2c507c [PATCH] Update cf... |
1271 1272 1273 1274 1275 1276 1277 1278 1279 |
break; } /* * keep track of original prio settings in case we have to temporarily * elevate the priority of this queue */ cfqq->org_ioprio = cfqq->ioprio; cfqq->org_ioprio_class = cfqq->ioprio_class; |
3b18152c3 [PATCH] CFQ io sc... |
1280 |
if (cfq_cfqq_on_rr(cfqq)) |
22e2c507c [PATCH] Update cf... |
1281 |
cfq_resort_rr_list(cfqq, 0); |
3b18152c3 [PATCH] CFQ io sc... |
1282 |
cfq_clear_cfqq_prio_changed(cfqq); |
22e2c507c [PATCH] Update cf... |
1283 1284 1285 1286 1287 1288 1289 1290 |
} static inline void changed_ioprio(struct cfq_queue *cfqq) { if (cfqq) { struct cfq_data *cfqd = cfqq->cfqd; spin_lock(cfqd->queue->queue_lock); |
3b18152c3 [PATCH] CFQ io sc... |
1291 |
cfq_mark_cfqq_prio_changed(cfqq); |
22e2c507c [PATCH] Update cf... |
1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 |
cfq_init_prio_data(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) { struct cfq_io_context *cic = ioc->cic; changed_ioprio(cic->cfqq); list_for_each_entry(cic, &cic->list, list) changed_ioprio(cic->cfqq); return 0; } static struct cfq_queue * |
3b18152c3 [PATCH] CFQ io sc... |
1313 |
cfq_get_queue(struct cfq_data *cfqd, unsigned int key, unsigned short ioprio, |
8267e268e [PATCH] gfp_t: bl... |
1314 |
gfp_t gfp_mask) |
22e2c507c [PATCH] Update cf... |
1315 1316 1317 1318 1319 |
{ const int hashval = hash_long(key, CFQ_QHASH_SHIFT); struct cfq_queue *cfqq, *new_cfqq = NULL; retry: |
3b18152c3 [PATCH] CFQ io sc... |
1320 |
cfqq = __cfq_find_cfq_hash(cfqd, key, ioprio, hashval); |
22e2c507c [PATCH] Update cf... |
1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 |
if (!cfqq) { if (new_cfqq) { cfqq = new_cfqq; new_cfqq = NULL; } else if (gfp_mask & __GFP_WAIT) { spin_unlock_irq(cfqd->queue->queue_lock); new_cfqq = kmem_cache_alloc(cfq_pool, gfp_mask); spin_lock_irq(cfqd->queue->queue_lock); goto retry; } else { cfqq = kmem_cache_alloc(cfq_pool, gfp_mask); if (!cfqq) goto out; } memset(cfqq, 0, sizeof(*cfqq)); 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; atomic_inc(&cfqd->ref); cfqq->service_last = 0; /* * set ->slice_left to allow preemption for a new process */ cfqq->slice_left = 2 * cfqd->cfq_slice_idle; |
3b18152c3 [PATCH] CFQ io sc... |
1354 1355 1356 |
cfq_mark_cfqq_idle_window(cfqq); cfq_mark_cfqq_prio_changed(cfqq); cfq_init_prio_data(cfqq); |
22e2c507c [PATCH] Update cf... |
1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 |
} if (new_cfqq) kmem_cache_free(cfq_pool, new_cfqq); atomic_inc(&cfqq->ref); out: WARN_ON((gfp_mask & __GFP_WAIT) && !cfqq); return cfqq; } |
1da177e4c Linux-2.6.12-rc2 |
1367 1368 1369 1370 1371 1372 1373 |
/* * Setup general io context and cfq io context. There can be several cfq * io contexts per general io context, if this process is doing io to more * than one device managed by cfq. Note that caller is holding a reference to * cfqq, so we don't need to worry about it disappearing */ static struct cfq_io_context * |
8267e268e [PATCH] gfp_t: bl... |
1374 |
cfq_get_io_context(struct cfq_data *cfqd, pid_t pid, gfp_t gfp_mask) |
1da177e4c Linux-2.6.12-rc2 |
1375 |
{ |
22e2c507c [PATCH] Update cf... |
1376 |
struct io_context *ioc = NULL; |
1da177e4c Linux-2.6.12-rc2 |
1377 |
struct cfq_io_context *cic; |
1da177e4c Linux-2.6.12-rc2 |
1378 |
|
22e2c507c [PATCH] Update cf... |
1379 |
might_sleep_if(gfp_mask & __GFP_WAIT); |
1da177e4c Linux-2.6.12-rc2 |
1380 |
|
22e2c507c [PATCH] Update cf... |
1381 |
ioc = get_io_context(gfp_mask); |
1da177e4c Linux-2.6.12-rc2 |
1382 1383 1384 1385 |
if (!ioc) return NULL; if ((cic = ioc->cic) == NULL) { |
22e2c507c [PATCH] Update cf... |
1386 |
cic = cfq_alloc_io_context(cfqd, gfp_mask); |
1da177e4c Linux-2.6.12-rc2 |
1387 1388 1389 |
if (cic == NULL) goto err; |
22e2c507c [PATCH] Update cf... |
1390 1391 1392 1393 |
/* * manually increment generic io_context usage count, it * cannot go away since we are already holding one ref to it */ |
1da177e4c Linux-2.6.12-rc2 |
1394 |
ioc->cic = cic; |
22e2c507c [PATCH] Update cf... |
1395 |
ioc->set_ioprio = cfq_ioc_set_ioprio; |
1da177e4c Linux-2.6.12-rc2 |
1396 |
cic->ioc = ioc; |
22e2c507c [PATCH] Update cf... |
1397 1398 |
cic->key = cfqd; atomic_inc(&cfqd->ref); |
1da177e4c Linux-2.6.12-rc2 |
1399 1400 |
} else { struct cfq_io_context *__cic; |
1da177e4c Linux-2.6.12-rc2 |
1401 1402 |
/* |
22e2c507c [PATCH] Update cf... |
1403 |
* the first cic on the list is actually the head itself |
1da177e4c Linux-2.6.12-rc2 |
1404 |
*/ |
22e2c507c [PATCH] Update cf... |
1405 |
if (cic->key == cfqd) |
1da177e4c Linux-2.6.12-rc2 |
1406 1407 1408 1409 1410 1411 1412 |
goto out; /* * cic exists, check if we already are there. linear search * should be ok here, the list will usually not be more than * 1 or a few entries long */ |
1da177e4c Linux-2.6.12-rc2 |
1413 1414 1415 1416 1417 |
list_for_each_entry(__cic, &cic->list, list) { /* * this process is already holding a reference to * this queue, so no need to get one more */ |
22e2c507c [PATCH] Update cf... |
1418 |
if (__cic->key == cfqd) { |
1da177e4c Linux-2.6.12-rc2 |
1419 |
cic = __cic; |
1da177e4c Linux-2.6.12-rc2 |
1420 1421 1422 |
goto out; } } |
1da177e4c Linux-2.6.12-rc2 |
1423 1424 1425 1426 1427 |
/* * nope, process doesn't have a cic assoicated with this * cfqq yet. get a new one and add to list */ |
22e2c507c [PATCH] Update cf... |
1428 |
__cic = cfq_alloc_io_context(cfqd, gfp_mask); |
1da177e4c Linux-2.6.12-rc2 |
1429 1430 1431 1432 |
if (__cic == NULL) goto err; __cic->ioc = ioc; |
22e2c507c [PATCH] Update cf... |
1433 1434 |
__cic->key = cfqd; atomic_inc(&cfqd->ref); |
1da177e4c Linux-2.6.12-rc2 |
1435 |
list_add(&__cic->list, &cic->list); |
1da177e4c Linux-2.6.12-rc2 |
1436 |
cic = __cic; |
1da177e4c Linux-2.6.12-rc2 |
1437 1438 1439 |
} out: |
1da177e4c Linux-2.6.12-rc2 |
1440 1441 1442 1443 1444 |
return cic; err: put_io_context(ioc); return NULL; } |
22e2c507c [PATCH] Update cf... |
1445 1446 |
static void cfq_update_io_thinktime(struct cfq_data *cfqd, struct cfq_io_context *cic) |
1da177e4c Linux-2.6.12-rc2 |
1447 |
{ |
22e2c507c [PATCH] Update cf... |
1448 |
unsigned long elapsed, ttime; |
1da177e4c Linux-2.6.12-rc2 |
1449 |
|
22e2c507c [PATCH] Update cf... |
1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 |
/* * if this context already has stuff queued, thinktime is from * last queue not last end */ #if 0 if (time_after(cic->last_end_request, cic->last_queue)) elapsed = jiffies - cic->last_end_request; else elapsed = jiffies - cic->last_queue; #else elapsed = jiffies - cic->last_end_request; #endif |
1da177e4c Linux-2.6.12-rc2 |
1462 |
|
22e2c507c [PATCH] Update cf... |
1463 |
ttime = min(elapsed, 2UL * cfqd->cfq_slice_idle); |
db3b5848e When cfq I/O sche... |
1464 |
|
22e2c507c [PATCH] Update cf... |
1465 1466 1467 1468 |
cic->ttime_samples = (7*cic->ttime_samples + 256) / 8; cic->ttime_total = (7*cic->ttime_total + 256*ttime) / 8; cic->ttime_mean = (cic->ttime_total + 128) / cic->ttime_samples; } |
1da177e4c Linux-2.6.12-rc2 |
1469 |
|
22e2c507c [PATCH] Update cf... |
1470 |
#define sample_valid(samples) ((samples) > 80) |
1da177e4c Linux-2.6.12-rc2 |
1471 |
|
22e2c507c [PATCH] Update cf... |
1472 1473 1474 1475 1476 1477 1478 1479 |
/* * Disable idle window if the process thinks too long or seeks so much that * it doesn't matter */ static void cfq_update_idle_window(struct cfq_data *cfqd, struct cfq_queue *cfqq, struct cfq_io_context *cic) { |
3b18152c3 [PATCH] CFQ io sc... |
1480 |
int enable_idle = cfq_cfqq_idle_window(cfqq); |
1da177e4c Linux-2.6.12-rc2 |
1481 |
|
22e2c507c [PATCH] Update cf... |
1482 1483 1484 1485 1486 1487 1488 |
if (!cic->ioc->task || !cfqd->cfq_slice_idle) enable_idle = 0; else if (sample_valid(cic->ttime_samples)) { if (cic->ttime_mean > cfqd->cfq_slice_idle) enable_idle = 0; else enable_idle = 1; |
1da177e4c Linux-2.6.12-rc2 |
1489 |
} |
3b18152c3 [PATCH] CFQ io sc... |
1490 1491 1492 1493 |
if (enable_idle) cfq_mark_cfqq_idle_window(cfqq); else cfq_clear_cfqq_idle_window(cfqq); |
22e2c507c [PATCH] Update cf... |
1494 |
} |
1da177e4c Linux-2.6.12-rc2 |
1495 |
|
22e2c507c [PATCH] Update cf... |
1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 |
/* * Check if new_cfqq should preempt the currently active queue. Return 0 for * no or if we aren't sure, a 1 will cause a preempt. */ static int cfq_should_preempt(struct cfq_data *cfqd, struct cfq_queue *new_cfqq, struct cfq_rq *crq) { struct cfq_queue *cfqq = cfqd->active_queue; if (cfq_class_idle(new_cfqq)) return 0; if (!cfqq) return 1; if (cfq_class_idle(cfqq)) return 1; |
3b18152c3 [PATCH] CFQ io sc... |
1515 |
if (!cfq_cfqq_wait_request(new_cfqq)) |
22e2c507c [PATCH] Update cf... |
1516 1517 1518 1519 1520 1521 |
return 0; /* * if it doesn't have slice left, forget it */ if (new_cfqq->slice_left < cfqd->cfq_slice_idle) return 0; |
3b18152c3 [PATCH] CFQ io sc... |
1522 |
if (cfq_crq_is_sync(crq) && !cfq_cfqq_sync(cfqq)) |
22e2c507c [PATCH] Update cf... |
1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 |
return 1; return 0; } /* * cfqq preempts the active queue. if we allowed preempt with no slice left, * let it have half of its nominal slice. */ 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); if (!cfqq->slice_left) cfqq->slice_left = cfq_prio_to_slice(cfqd, cfqq) / 2; cfqq->slice_end = cfqq->slice_left + jiffies; |
3b18152c3 [PATCH] CFQ io sc... |
1543 |
__cfq_slice_expired(cfqd, cfqq, 1); |
22e2c507c [PATCH] Update cf... |
1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 |
__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; if (!blk_queue_plugged(q)) q->request_fn(q); else __generic_unplug_device(q); } /* * Called when a new fs request (crq) 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) { |
9c2c38a12 [PATCH] cfq-iosch... |
1568 |
struct cfq_io_context *cic; |
22e2c507c [PATCH] Update cf... |
1569 1570 |
cfqq->next_crq = cfq_choose_req(cfqd, cfqq->next_crq, crq); |
9c2c38a12 [PATCH] cfq-iosch... |
1571 1572 1573 1574 1575 1576 |
/* * 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)) return; |
22e2c507c [PATCH] Update cf... |
1577 |
|
9c2c38a12 [PATCH] cfq-iosch... |
1578 |
cic = crq->io_context; |
22e2c507c [PATCH] Update cf... |
1579 |
|
9c2c38a12 [PATCH] cfq-iosch... |
1580 1581 1582 1583 |
cfq_update_io_thinktime(cfqd, cic); cfq_update_idle_window(cfqd, cfqq, cic); cic->last_queue = jiffies; |
22e2c507c [PATCH] Update cf... |
1584 1585 1586 1587 1588 1589 1590 |
if (cfqq == cfqd->active_queue) { /* * if we are waiting for a request for this queue, let it rip * immediately and flag that we must not expire this queue * just now */ |
3b18152c3 [PATCH] CFQ io sc... |
1591 1592 |
if (cfq_cfqq_wait_request(cfqq)) { cfq_mark_cfqq_must_dispatch(cfqq); |
22e2c507c [PATCH] Update cf... |
1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 |
del_timer(&cfqd->idle_slice_timer); cfq_start_queueing(cfqd, cfqq); } } else if (cfq_should_preempt(cfqd, cfqq, crq)) { /* * not the active queue - expire current slice if it is * idle and has expired it's mean thinktime or this new queue * has some old slice time left and is of higher priority */ cfq_preempt_queue(cfqd, cfqq); |
3b18152c3 [PATCH] CFQ io sc... |
1603 |
cfq_mark_cfqq_must_dispatch(cfqq); |
22e2c507c [PATCH] Update cf... |
1604 1605 |
cfq_start_queueing(cfqd, cfqq); } |
1da177e4c Linux-2.6.12-rc2 |
1606 |
} |
b4878f245 [PATCH] 02/05: up... |
1607 |
static void cfq_insert_request(request_queue_t *q, struct request *rq) |
1da177e4c Linux-2.6.12-rc2 |
1608 |
{ |
b4878f245 [PATCH] 02/05: up... |
1609 |
struct cfq_data *cfqd = q->elevator->elevator_data; |
22e2c507c [PATCH] Update cf... |
1610 1611 1612 1613 |
struct cfq_rq *crq = RQ_DATA(rq); struct cfq_queue *cfqq = crq->cfq_queue; cfq_init_prio_data(cfqq); |
1da177e4c Linux-2.6.12-rc2 |
1614 1615 |
cfq_add_crq_rb(crq); |
1da177e4c Linux-2.6.12-rc2 |
1616 |
|
22e2c507c [PATCH] Update cf... |
1617 |
list_add_tail(&rq->queuelist, &cfqq->fifo); |
98b11471d [PATCH] 04/05 rem... |
1618 |
if (rq_mergeable(rq)) |
22e2c507c [PATCH] Update cf... |
1619 |
cfq_add_crq_hash(cfqd, crq); |
22e2c507c [PATCH] Update cf... |
1620 |
cfq_crq_enqueued(cfqd, cfqq, crq); |
1da177e4c Linux-2.6.12-rc2 |
1621 |
} |
1da177e4c Linux-2.6.12-rc2 |
1622 1623 1624 |
static void cfq_completed_request(request_queue_t *q, struct request *rq) { struct cfq_rq *crq = RQ_DATA(rq); |
b4878f245 [PATCH] 02/05: up... |
1625 1626 1627 1628 |
struct cfq_queue *cfqq = crq->cfq_queue; struct cfq_data *cfqd = cfqq->cfqd; const int sync = cfq_crq_is_sync(crq); unsigned long now; |
1da177e4c Linux-2.6.12-rc2 |
1629 |
|
b4878f245 [PATCH] 02/05: up... |
1630 |
now = jiffies; |
1da177e4c Linux-2.6.12-rc2 |
1631 |
|
b4878f245 [PATCH] 02/05: up... |
1632 1633 1634 1635 |
WARN_ON(!cfqd->rq_in_driver); WARN_ON(!cfqq->on_dispatch[sync]); cfqd->rq_in_driver--; cfqq->on_dispatch[sync]--; |
1da177e4c Linux-2.6.12-rc2 |
1636 |
|
b4878f245 [PATCH] 02/05: up... |
1637 1638 |
if (!cfq_class_idle(cfqq)) cfqd->last_end_request = now; |
3b18152c3 [PATCH] CFQ io sc... |
1639 |
|
b4878f245 [PATCH] 02/05: up... |
1640 1641 1642 1643 1644 1645 1646 1647 1648 |
if (!cfq_cfqq_dispatched(cfqq)) { if (cfq_cfqq_on_rr(cfqq)) { cfqq->service_last = now; cfq_resort_rr_list(cfqq, 0); } if (cfq_cfqq_expired(cfqq)) { __cfq_slice_expired(cfqd, cfqq, 0); cfq_schedule_dispatch(cfqd); } |
1da177e4c Linux-2.6.12-rc2 |
1649 |
} |
b4878f245 [PATCH] 02/05: up... |
1650 1651 |
if (cfq_crq_is_sync(crq)) crq->io_context->last_end_request = now; |
1da177e4c Linux-2.6.12-rc2 |
1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 |
} 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; } |
22e2c507c [PATCH] Update cf... |
1677 1678 1679 1680 1681 |
/* * we temporarily boost lower priority queues if they are holding fs exclusive * resources. they are boosted to normal prio (CLASS_BE/4) */ static void cfq_prio_boost(struct cfq_queue *cfqq) |
1da177e4c Linux-2.6.12-rc2 |
1682 |
{ |
22e2c507c [PATCH] Update cf... |
1683 1684 |
const int ioprio_class = cfqq->ioprio_class; const int ioprio = cfqq->ioprio; |
1da177e4c Linux-2.6.12-rc2 |
1685 |
|
22e2c507c [PATCH] Update cf... |
1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 |
if (has_fs_excl()) { /* * boost idle prio on transactions that would lock out other * users of the filesystem */ if (cfq_class_idle(cfqq)) cfqq->ioprio_class = IOPRIO_CLASS_BE; if (cfqq->ioprio > IOPRIO_NORM) cfqq->ioprio = IOPRIO_NORM; } else { /* * check if we need to unboost the queue */ if (cfqq->ioprio_class != cfqq->org_ioprio_class) cfqq->ioprio_class = cfqq->org_ioprio_class; if (cfqq->ioprio != cfqq->org_ioprio) cfqq->ioprio = cfqq->org_ioprio; } |
1da177e4c Linux-2.6.12-rc2 |
1704 |
|
22e2c507c [PATCH] Update cf... |
1705 1706 1707 1708 |
/* * refile between round-robin lists if we moved the priority class */ if ((ioprio_class != cfqq->ioprio_class || ioprio != cfqq->ioprio) && |
3b18152c3 [PATCH] CFQ io sc... |
1709 |
cfq_cfqq_on_rr(cfqq)) |
22e2c507c [PATCH] Update cf... |
1710 1711 |
cfq_resort_rr_list(cfqq, 0); } |
1da177e4c Linux-2.6.12-rc2 |
1712 |
|
22e2c507c [PATCH] Update cf... |
1713 1714 1715 1716 |
static inline pid_t cfq_queue_pid(struct task_struct *task, int rw) { if (rw == READ || process_sync(task)) return task->pid; |
1da177e4c Linux-2.6.12-rc2 |
1717 |
|
22e2c507c [PATCH] Update cf... |
1718 1719 |
return CFQ_KEY_ASYNC; } |
1da177e4c Linux-2.6.12-rc2 |
1720 |
|
22e2c507c [PATCH] Update cf... |
1721 1722 1723 1724 |
static inline int __cfq_may_queue(struct cfq_data *cfqd, struct cfq_queue *cfqq, struct task_struct *task, int rw) { |
3b18152c3 [PATCH] CFQ io sc... |
1725 1726 |
#if 1 if ((cfq_cfqq_wait_request(cfqq) || cfq_cfqq_must_alloc(cfqq)) && |
99f95e528 [PATCH] cfq build... |
1727 |
!cfq_cfqq_must_alloc_slice(cfqq)) { |
3b18152c3 [PATCH] CFQ io sc... |
1728 |
cfq_mark_cfqq_must_alloc_slice(cfqq); |
22e2c507c [PATCH] Update cf... |
1729 |
return ELV_MQUEUE_MUST; |
3b18152c3 [PATCH] CFQ io sc... |
1730 |
} |
1da177e4c Linux-2.6.12-rc2 |
1731 |
|
22e2c507c [PATCH] Update cf... |
1732 |
return ELV_MQUEUE_MAY; |
3b18152c3 [PATCH] CFQ io sc... |
1733 |
#else |
22e2c507c [PATCH] Update cf... |
1734 1735 |
if (!cfqq || task->flags & PF_MEMALLOC) return ELV_MQUEUE_MAY; |
3b18152c3 [PATCH] CFQ io sc... |
1736 1737 |
if (!cfqq->allocated[rw] || cfq_cfqq_must_alloc(cfqq)) { if (cfq_cfqq_wait_request(cfqq)) |
22e2c507c [PATCH] Update cf... |
1738 |
return ELV_MQUEUE_MUST; |
1da177e4c Linux-2.6.12-rc2 |
1739 |
|
22e2c507c [PATCH] Update cf... |
1740 1741 1742 1743 |
/* * only allow 1 ELV_MQUEUE_MUST per slice, otherwise we * can quickly flood the queue with writes from a single task */ |
99f95e528 [PATCH] cfq build... |
1744 |
if (rw == READ || !cfq_cfqq_must_alloc_slice(cfqq)) { |
3b18152c3 [PATCH] CFQ io sc... |
1745 |
cfq_mark_cfqq_must_alloc_slice(cfqq); |
22e2c507c [PATCH] Update cf... |
1746 |
return ELV_MQUEUE_MUST; |
1da177e4c Linux-2.6.12-rc2 |
1747 |
} |
22e2c507c [PATCH] Update cf... |
1748 1749 |
return ELV_MQUEUE_MAY; |
1da177e4c Linux-2.6.12-rc2 |
1750 |
} |
22e2c507c [PATCH] Update cf... |
1751 1752 1753 1754 1755 |
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; |
1da177e4c Linux-2.6.12-rc2 |
1756 |
|
22e2c507c [PATCH] Update cf... |
1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 |
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) { struct cfq_data *cfqd = q->elevator->elevator_data; struct task_struct *tsk = current; struct cfq_queue *cfqq; /* * don't force setup of a queue from here, as a call to may_queue * does not necessarily imply that a request actually will be queued. * so just lookup a possibly existing queue, or return 'may queue' * if that fails */ |
3b18152c3 [PATCH] CFQ io sc... |
1780 |
cfqq = cfq_find_cfq_hash(cfqd, cfq_queue_pid(tsk, rw), tsk->ioprio); |
22e2c507c [PATCH] Update cf... |
1781 1782 1783 1784 1785 1786 1787 1788 |
if (cfqq) { cfq_init_prio_data(cfqq); cfq_prio_boost(cfqq); return __cfq_may_queue(cfqd, cfqq, tsk, rw); } return ELV_MQUEUE_MAY; |
1da177e4c Linux-2.6.12-rc2 |
1789 1790 1791 1792 |
} static void cfq_check_waiters(request_queue_t *q, struct cfq_queue *cfqq) { |
22e2c507c [PATCH] Update cf... |
1793 |
struct cfq_data *cfqd = q->elevator->elevator_data; |
1da177e4c Linux-2.6.12-rc2 |
1794 |
struct request_list *rl = &q->rq; |
1da177e4c Linux-2.6.12-rc2 |
1795 |
|
22e2c507c [PATCH] Update cf... |
1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 |
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]); } |
1da177e4c Linux-2.6.12-rc2 |
1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 |
} /* * 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); if (crq) { struct cfq_queue *cfqq = crq->cfq_queue; |
22e2c507c [PATCH] Update cf... |
1819 |
const int rw = rq_data_dir(rq); |
1da177e4c Linux-2.6.12-rc2 |
1820 |
|
22e2c507c [PATCH] Update cf... |
1821 1822 |
BUG_ON(!cfqq->allocated[rw]); cfqq->allocated[rw]--; |
1da177e4c Linux-2.6.12-rc2 |
1823 |
|
22e2c507c [PATCH] Update cf... |
1824 |
put_io_context(crq->io_context->ioc); |
1da177e4c Linux-2.6.12-rc2 |
1825 1826 1827 |
mempool_free(crq, cfqd->crq_pool); rq->elevator_private = NULL; |
1da177e4c Linux-2.6.12-rc2 |
1828 1829 1830 1831 1832 1833 |
cfq_check_waiters(q, cfqq); cfq_put_queue(cfqq); } } /* |
22e2c507c [PATCH] Update cf... |
1834 |
* Allocate cfq data structures associated with this request. |
1da177e4c Linux-2.6.12-rc2 |
1835 |
*/ |
22e2c507c [PATCH] Update cf... |
1836 1837 |
static int cfq_set_request(request_queue_t *q, struct request *rq, struct bio *bio, |
8267e268e [PATCH] gfp_t: bl... |
1838 |
gfp_t gfp_mask) |
1da177e4c Linux-2.6.12-rc2 |
1839 1840 |
{ struct cfq_data *cfqd = q->elevator->elevator_data; |
3b18152c3 [PATCH] CFQ io sc... |
1841 |
struct task_struct *tsk = current; |
1da177e4c Linux-2.6.12-rc2 |
1842 1843 |
struct cfq_io_context *cic; const int rw = rq_data_dir(rq); |
3b18152c3 [PATCH] CFQ io sc... |
1844 |
pid_t key = cfq_queue_pid(tsk, rw); |
22e2c507c [PATCH] Update cf... |
1845 |
struct cfq_queue *cfqq; |
1da177e4c Linux-2.6.12-rc2 |
1846 1847 1848 1849 |
struct cfq_rq *crq; unsigned long flags; might_sleep_if(gfp_mask & __GFP_WAIT); |
3b18152c3 [PATCH] CFQ io sc... |
1850 |
cic = cfq_get_io_context(cfqd, key, gfp_mask); |
22e2c507c [PATCH] Update cf... |
1851 |
|
1da177e4c Linux-2.6.12-rc2 |
1852 |
spin_lock_irqsave(q->queue_lock, flags); |
22e2c507c [PATCH] Update cf... |
1853 1854 1855 1856 |
if (!cic) goto queue_fail; if (!cic->cfqq) { |
3b18152c3 [PATCH] CFQ io sc... |
1857 |
cfqq = cfq_get_queue(cfqd, key, tsk->ioprio, gfp_mask); |
22e2c507c [PATCH] Update cf... |
1858 1859 |
if (!cfqq) goto queue_fail; |
1da177e4c Linux-2.6.12-rc2 |
1860 |
|
22e2c507c [PATCH] Update cf... |
1861 1862 1863 |
cic->cfqq = cfqq; } else cfqq = cic->cfqq; |
1da177e4c Linux-2.6.12-rc2 |
1864 1865 |
cfqq->allocated[rw]++; |
3b18152c3 [PATCH] CFQ io sc... |
1866 |
cfq_clear_cfqq_must_alloc(cfqq); |
22e2c507c [PATCH] Update cf... |
1867 1868 |
cfqd->rq_starved = 0; atomic_inc(&cfqq->ref); |
1da177e4c Linux-2.6.12-rc2 |
1869 |
spin_unlock_irqrestore(q->queue_lock, flags); |
1da177e4c Linux-2.6.12-rc2 |
1870 1871 1872 1873 1874 1875 1876 1877 |
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; |
3b18152c3 [PATCH] CFQ io sc... |
1878 1879 1880 1881 1882 |
if (rw == READ || process_sync(tsk)) cfq_mark_crq_is_sync(crq); else cfq_clear_crq_is_sync(crq); |
1da177e4c Linux-2.6.12-rc2 |
1883 |
rq->elevator_private = crq; |
1da177e4c Linux-2.6.12-rc2 |
1884 1885 |
return 0; } |
1da177e4c Linux-2.6.12-rc2 |
1886 1887 |
spin_lock_irqsave(q->queue_lock, flags); cfqq->allocated[rw]--; |
22e2c507c [PATCH] Update cf... |
1888 |
if (!(cfqq->allocated[0] + cfqq->allocated[1])) |
3b18152c3 [PATCH] CFQ io sc... |
1889 |
cfq_mark_cfqq_must_alloc(cfqq); |
1da177e4c Linux-2.6.12-rc2 |
1890 |
cfq_put_queue(cfqq); |
22e2c507c [PATCH] Update cf... |
1891 1892 1893 1894 1895 1896 1897 1898 1899 |
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; |
3b18152c3 [PATCH] CFQ io sc... |
1900 |
cfq_schedule_dispatch(cfqd); |
1da177e4c Linux-2.6.12-rc2 |
1901 1902 1903 |
spin_unlock_irqrestore(q->queue_lock, flags); return 1; } |
22e2c507c [PATCH] Update cf... |
1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 |
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); } /* * Timer running if the active_queue is currently idling inside its time slice */ static void cfq_idle_slice_timer(unsigned long data) { struct cfq_data *cfqd = (struct cfq_data *) data; struct cfq_queue *cfqq; unsigned long flags; spin_lock_irqsave(cfqd->queue->queue_lock, flags); if ((cfqq = cfqd->active_queue) != NULL) { unsigned long now = jiffies; /* * expired */ if (time_after(now, cfqq->slice_end)) goto expire; /* * only expire and reinvoke request handler, if there are * other queues with pending requests */ |
b4878f245 [PATCH] 02/05: up... |
1955 |
if (!cfqd->busy_queues) { |
22e2c507c [PATCH] Update cf... |
1956 1957 1958 1959 1960 1961 1962 1963 1964 |
cfqd->idle_slice_timer.expires = min(now + cfqd->cfq_slice_idle, cfqq->slice_end); add_timer(&cfqd->idle_slice_timer); goto out_cont; } /* * not expired and it has a request pending, let it dispatch */ if (!RB_EMPTY(&cfqq->sort_list)) { |
3b18152c3 [PATCH] CFQ io sc... |
1965 |
cfq_mark_cfqq_must_dispatch(cfqq); |
22e2c507c [PATCH] Update cf... |
1966 1967 1968 1969 1970 1971 |
goto out_kick; } } expire: cfq_slice_expired(cfqd, 0); out_kick: |
3b18152c3 [PATCH] CFQ io sc... |
1972 |
cfq_schedule_dispatch(cfqd); |
22e2c507c [PATCH] Update cf... |
1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 |
out_cont: spin_unlock_irqrestore(cfqd->queue->queue_lock, flags); } /* * Timer running if an idle class queue is waiting for service */ static void cfq_idle_class_timer(unsigned long data) { struct cfq_data *cfqd = (struct cfq_data *) data; unsigned long flags, end; spin_lock_irqsave(cfqd->queue->queue_lock, flags); /* * race with a non-idle queue, reset timer */ end = cfqd->last_end_request + CFQ_IDLE_GRACE; if (!time_after_eq(jiffies, end)) { cfqd->idle_class_timer.expires = end; add_timer(&cfqd->idle_class_timer); } else |
3b18152c3 [PATCH] CFQ io sc... |
1995 |
cfq_schedule_dispatch(cfqd); |
22e2c507c [PATCH] Update cf... |
1996 1997 1998 |
spin_unlock_irqrestore(cfqd->queue->queue_lock, flags); } |
3b18152c3 [PATCH] CFQ io sc... |
1999 2000 2001 2002 2003 2004 |
static void cfq_shutdown_timer_wq(struct cfq_data *cfqd) { del_timer_sync(&cfqd->idle_slice_timer); del_timer_sync(&cfqd->idle_class_timer); blk_sync_queue(cfqd->queue); } |
22e2c507c [PATCH] Update cf... |
2005 |
|
1da177e4c Linux-2.6.12-rc2 |
2006 2007 2008 2009 2010 2011 |
static void cfq_put_cfqd(struct cfq_data *cfqd) { request_queue_t *q = cfqd->queue; if (!atomic_dec_and_test(&cfqd->ref)) return; |
96c51ce94 [PATCH] CFQ io sc... |
2012 |
cfq_shutdown_timer_wq(cfqd); |
4fc207419 [PATCH] Fix on-th... |
2013 |
blk_put_queue(q); |
96c51ce94 [PATCH] CFQ io sc... |
2014 |
|
1da177e4c Linux-2.6.12-rc2 |
2015 2016 2017 2018 2019 2020 2021 2022 |
mempool_destroy(cfqd->crq_pool); kfree(cfqd->crq_hash); kfree(cfqd->cfq_hash); kfree(cfqd); } static void cfq_exit_queue(elevator_t *e) { |
22e2c507c [PATCH] Update cf... |
2023 |
struct cfq_data *cfqd = e->elevator_data; |
3b18152c3 [PATCH] CFQ io sc... |
2024 |
cfq_shutdown_timer_wq(cfqd); |
22e2c507c [PATCH] Update cf... |
2025 |
cfq_put_cfqd(cfqd); |
1da177e4c Linux-2.6.12-rc2 |
2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 |
} static int cfq_init_queue(request_queue_t *q, elevator_t *e) { struct cfq_data *cfqd; int i; cfqd = kmalloc(sizeof(*cfqd), GFP_KERNEL); if (!cfqd) return -ENOMEM; memset(cfqd, 0, sizeof(*cfqd)); |
22e2c507c [PATCH] Update cf... |
2038 2039 2040 2041 2042 2043 2044 |
for (i = 0; i < CFQ_PRIO_LISTS; i++) INIT_LIST_HEAD(&cfqd->rr_list[i]); INIT_LIST_HEAD(&cfqd->busy_rr); INIT_LIST_HEAD(&cfqd->cur_rr); INIT_LIST_HEAD(&cfqd->idle_rr); |
1da177e4c Linux-2.6.12-rc2 |
2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 |
INIT_LIST_HEAD(&cfqd->empty_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(BLKDEV_MIN_RQ, mempool_alloc_slab, mempool_free_slab, 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; |
35797132b [PATCH] cfq-iosch... |
2067 |
atomic_inc(&q->refcnt); |
1da177e4c Linux-2.6.12-rc2 |
2068 |
|
22e2c507c [PATCH] Update cf... |
2069 |
cfqd->max_queued = q->nr_requests / 4; |
1da177e4c Linux-2.6.12-rc2 |
2070 |
q->nr_batching = cfq_queued; |
22e2c507c [PATCH] Update cf... |
2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 |
init_timer(&cfqd->idle_slice_timer); cfqd->idle_slice_timer.function = cfq_idle_slice_timer; cfqd->idle_slice_timer.data = (unsigned long) cfqd; init_timer(&cfqd->idle_class_timer); cfqd->idle_class_timer.function = cfq_idle_class_timer; cfqd->idle_class_timer.data = (unsigned long) cfqd; INIT_WORK(&cfqd->unplug_work, cfq_kick_queue, q); |
1da177e4c Linux-2.6.12-rc2 |
2081 2082 2083 2084 |
atomic_set(&cfqd->ref, 1); cfqd->cfq_queued = cfq_queued; cfqd->cfq_quantum = cfq_quantum; |
22e2c507c [PATCH] Update cf... |
2085 2086 |
cfqd->cfq_fifo_expire[0] = cfq_fifo_expire[0]; cfqd->cfq_fifo_expire[1] = cfq_fifo_expire[1]; |
1da177e4c Linux-2.6.12-rc2 |
2087 2088 |
cfqd->cfq_back_max = cfq_back_max; cfqd->cfq_back_penalty = cfq_back_penalty; |
22e2c507c [PATCH] Update cf... |
2089 2090 2091 2092 2093 |
cfqd->cfq_slice[0] = cfq_slice_async; cfqd->cfq_slice[1] = cfq_slice_sync; cfqd->cfq_slice_async_rq = cfq_slice_async_rq; cfqd->cfq_slice_idle = cfq_slice_idle; cfqd->cfq_max_depth = cfq_max_depth; |
3b18152c3 [PATCH] CFQ io sc... |
2094 |
|
1da177e4c Linux-2.6.12-rc2 |
2095 2096 2097 2098 2099 2100 2101 2102 2103 2104 2105 2106 2107 2108 2109 2110 2111 2112 2113 2114 2115 2116 2117 2118 2119 2120 2121 2122 2123 2124 2125 2126 2127 2128 2129 2130 2131 2132 2133 2134 2135 2136 |
return 0; out_crqpool: kfree(cfqd->cfq_hash); out_cfqhash: kfree(cfqd->crq_hash); out_crqhash: kfree(cfqd); return -ENOMEM; } 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) kmem_cache_destroy(cfq_ioc_pool); } 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) goto fail; cfq_ioc_pool = kmem_cache_create("cfq_ioc_pool", sizeof(struct cfq_io_context), 0, 0, NULL, NULL); if (!cfq_ioc_pool) goto fail; return 0; fail: cfq_slab_kill(); return -ENOMEM; } |
1da177e4c Linux-2.6.12-rc2 |
2137 2138 2139 2140 2141 2142 2143 2144 2145 2146 2147 2148 2149 2150 2151 2152 2153 2154 2155 2156 2157 2158 2159 2160 |
/* * sysfs parts below --> */ struct cfq_fs_entry { struct attribute attr; ssize_t (*show)(struct cfq_data *, char *); ssize_t (*store)(struct cfq_data *, const char *, size_t); }; static ssize_t cfq_var_show(unsigned int var, char *page) { return sprintf(page, "%d ", var); } static ssize_t cfq_var_store(unsigned int *var, const char *page, size_t count) { char *p = (char *) page; *var = simple_strtoul(p, &p, 10); return count; } |
1da177e4c Linux-2.6.12-rc2 |
2161 2162 2163 2164 2165 2166 2167 2168 2169 2170 |
#define SHOW_FUNCTION(__FUNC, __VAR, __CONV) \ static ssize_t __FUNC(struct cfq_data *cfqd, char *page) \ { \ unsigned int __data = __VAR; \ if (__CONV) \ __data = jiffies_to_msecs(__data); \ return cfq_var_show(__data, (page)); \ } SHOW_FUNCTION(cfq_quantum_show, cfqd->cfq_quantum, 0); SHOW_FUNCTION(cfq_queued_show, cfqd->cfq_queued, 0); |
22e2c507c [PATCH] Update cf... |
2171 2172 |
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); |
1da177e4c Linux-2.6.12-rc2 |
2173 2174 |
SHOW_FUNCTION(cfq_back_max_show, cfqd->cfq_back_max, 0); SHOW_FUNCTION(cfq_back_penalty_show, cfqd->cfq_back_penalty, 0); |
22e2c507c [PATCH] Update cf... |
2175 2176 2177 2178 2179 |
SHOW_FUNCTION(cfq_slice_idle_show, cfqd->cfq_slice_idle, 1); SHOW_FUNCTION(cfq_slice_sync_show, cfqd->cfq_slice[1], 1); SHOW_FUNCTION(cfq_slice_async_show, cfqd->cfq_slice[0], 1); SHOW_FUNCTION(cfq_slice_async_rq_show, cfqd->cfq_slice_async_rq, 0); SHOW_FUNCTION(cfq_max_depth_show, cfqd->cfq_max_depth, 0); |
1da177e4c Linux-2.6.12-rc2 |
2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 |
#undef SHOW_FUNCTION #define STORE_FUNCTION(__FUNC, __PTR, MIN, MAX, __CONV) \ static ssize_t __FUNC(struct cfq_data *cfqd, const char *page, size_t count) \ { \ unsigned int __data; \ int ret = cfq_var_store(&__data, (page), count); \ if (__data < (MIN)) \ __data = (MIN); \ else if (__data > (MAX)) \ __data = (MAX); \ if (__CONV) \ *(__PTR) = msecs_to_jiffies(__data); \ else \ *(__PTR) = __data; \ 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); |
22e2c507c [PATCH] Update cf... |
2199 2200 |
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); |
1da177e4c Linux-2.6.12-rc2 |
2201 2202 |
STORE_FUNCTION(cfq_back_max_store, &cfqd->cfq_back_max, 0, UINT_MAX, 0); STORE_FUNCTION(cfq_back_penalty_store, &cfqd->cfq_back_penalty, 1, UINT_MAX, 0); |
22e2c507c [PATCH] Update cf... |
2203 2204 2205 2206 2207 |
STORE_FUNCTION(cfq_slice_idle_store, &cfqd->cfq_slice_idle, 0, UINT_MAX, 1); STORE_FUNCTION(cfq_slice_sync_store, &cfqd->cfq_slice[1], 1, UINT_MAX, 1); STORE_FUNCTION(cfq_slice_async_store, &cfqd->cfq_slice[0], 1, UINT_MAX, 1); STORE_FUNCTION(cfq_slice_async_rq_store, &cfqd->cfq_slice_async_rq, 1, UINT_MAX, 0); STORE_FUNCTION(cfq_max_depth_store, &cfqd->cfq_max_depth, 1, UINT_MAX, 0); |
1da177e4c Linux-2.6.12-rc2 |
2208 2209 2210 2211 2212 2213 2214 2215 2216 2217 2218 2219 |
#undef STORE_FUNCTION static struct cfq_fs_entry cfq_quantum_entry = { .attr = {.name = "quantum", .mode = S_IRUGO | S_IWUSR }, .show = cfq_quantum_show, .store = cfq_quantum_store, }; static struct cfq_fs_entry cfq_queued_entry = { .attr = {.name = "queued", .mode = S_IRUGO | S_IWUSR }, .show = cfq_queued_show, .store = cfq_queued_store, }; |
22e2c507c [PATCH] Update cf... |
2220 |
static struct cfq_fs_entry cfq_fifo_expire_sync_entry = { |
1da177e4c Linux-2.6.12-rc2 |
2221 |
.attr = {.name = "fifo_expire_sync", .mode = S_IRUGO | S_IWUSR }, |
22e2c507c [PATCH] Update cf... |
2222 2223 |
.show = cfq_fifo_expire_sync_show, .store = cfq_fifo_expire_sync_store, |
1da177e4c Linux-2.6.12-rc2 |
2224 |
}; |
22e2c507c [PATCH] Update cf... |
2225 |
static struct cfq_fs_entry cfq_fifo_expire_async_entry = { |
1da177e4c Linux-2.6.12-rc2 |
2226 |
.attr = {.name = "fifo_expire_async", .mode = S_IRUGO | S_IWUSR }, |
22e2c507c [PATCH] Update cf... |
2227 2228 |
.show = cfq_fifo_expire_async_show, .store = cfq_fifo_expire_async_store, |
1da177e4c Linux-2.6.12-rc2 |
2229 2230 2231 2232 2233 2234 2235 2236 2237 2238 2239 |
}; static struct cfq_fs_entry cfq_back_max_entry = { .attr = {.name = "back_seek_max", .mode = S_IRUGO | S_IWUSR }, .show = cfq_back_max_show, .store = cfq_back_max_store, }; static struct cfq_fs_entry cfq_back_penalty_entry = { .attr = {.name = "back_seek_penalty", .mode = S_IRUGO | S_IWUSR }, .show = cfq_back_penalty_show, .store = cfq_back_penalty_store, }; |
22e2c507c [PATCH] Update cf... |
2240 2241 2242 2243 |
static struct cfq_fs_entry cfq_slice_sync_entry = { .attr = {.name = "slice_sync", .mode = S_IRUGO | S_IWUSR }, .show = cfq_slice_sync_show, .store = cfq_slice_sync_store, |
1da177e4c Linux-2.6.12-rc2 |
2244 |
}; |
22e2c507c [PATCH] Update cf... |
2245 2246 2247 2248 2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260 2261 2262 2263 |
static struct cfq_fs_entry cfq_slice_async_entry = { .attr = {.name = "slice_async", .mode = S_IRUGO | S_IWUSR }, .show = cfq_slice_async_show, .store = cfq_slice_async_store, }; static struct cfq_fs_entry cfq_slice_async_rq_entry = { .attr = {.name = "slice_async_rq", .mode = S_IRUGO | S_IWUSR }, .show = cfq_slice_async_rq_show, .store = cfq_slice_async_rq_store, }; static struct cfq_fs_entry cfq_slice_idle_entry = { .attr = {.name = "slice_idle", .mode = S_IRUGO | S_IWUSR }, .show = cfq_slice_idle_show, .store = cfq_slice_idle_store, }; static struct cfq_fs_entry cfq_max_depth_entry = { .attr = {.name = "max_depth", .mode = S_IRUGO | S_IWUSR }, .show = cfq_max_depth_show, .store = cfq_max_depth_store, |
1da177e4c Linux-2.6.12-rc2 |
2264 |
}; |
3b18152c3 [PATCH] CFQ io sc... |
2265 |
|
1da177e4c Linux-2.6.12-rc2 |
2266 2267 2268 |
static struct attribute *default_attrs[] = { &cfq_quantum_entry.attr, &cfq_queued_entry.attr, |
22e2c507c [PATCH] Update cf... |
2269 2270 |
&cfq_fifo_expire_sync_entry.attr, &cfq_fifo_expire_async_entry.attr, |
1da177e4c Linux-2.6.12-rc2 |
2271 2272 |
&cfq_back_max_entry.attr, &cfq_back_penalty_entry.attr, |
22e2c507c [PATCH] Update cf... |
2273 2274 2275 2276 2277 |
&cfq_slice_sync_entry.attr, &cfq_slice_async_entry.attr, &cfq_slice_async_rq_entry.attr, &cfq_slice_idle_entry.attr, &cfq_max_depth_entry.attr, |
1da177e4c Linux-2.6.12-rc2 |
2278 2279 2280 2281 2282 2283 2284 2285 2286 2287 2288 2289 |
NULL, }; #define to_cfq(atr) container_of((atr), struct cfq_fs_entry, attr) static ssize_t cfq_attr_show(struct kobject *kobj, struct attribute *attr, char *page) { elevator_t *e = container_of(kobj, elevator_t, kobj); struct cfq_fs_entry *entry = to_cfq(attr); if (!entry->show) |
6c1852a08 [PATCH] sysfs: (d... |
2290 |
return -EIO; |
1da177e4c Linux-2.6.12-rc2 |
2291 2292 2293 2294 2295 2296 2297 2298 2299 2300 2301 2302 |
return entry->show(e->elevator_data, page); } static ssize_t cfq_attr_store(struct kobject *kobj, struct attribute *attr, const char *page, size_t length) { elevator_t *e = container_of(kobj, elevator_t, kobj); struct cfq_fs_entry *entry = to_cfq(attr); if (!entry->store) |
6c1852a08 [PATCH] sysfs: (d... |
2303 |
return -EIO; |
1da177e4c Linux-2.6.12-rc2 |
2304 2305 2306 2307 2308 2309 2310 2311 2312 2313 2314 2315 2316 2317 2318 2319 2320 2321 2322 |
return entry->store(e->elevator_data, page, length); } static struct sysfs_ops cfq_sysfs_ops = { .show = cfq_attr_show, .store = cfq_attr_store, }; static struct kobj_type cfq_ktype = { .sysfs_ops = &cfq_sysfs_ops, .default_attrs = default_attrs, }; static struct elevator_type iosched_cfq = { .ops = { .elevator_merge_fn = cfq_merge, .elevator_merged_fn = cfq_merged_request, .elevator_merge_req_fn = cfq_merged_requests, |
b4878f245 [PATCH] 02/05: up... |
2323 |
.elevator_dispatch_fn = cfq_dispatch_requests, |
1da177e4c Linux-2.6.12-rc2 |
2324 |
.elevator_add_req_fn = cfq_insert_request, |
b4878f245 [PATCH] 02/05: up... |
2325 |
.elevator_activate_req_fn = cfq_activate_request, |
1da177e4c Linux-2.6.12-rc2 |
2326 2327 2328 2329 2330 2331 2332 2333 2334 2335 2336 2337 2338 2339 2340 2341 2342 2343 2344 |
.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_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, }, .elevator_ktype = &cfq_ktype, .elevator_name = "cfq", .elevator_owner = THIS_MODULE, }; static int __init cfq_init(void) { int ret; |
22e2c507c [PATCH] Update cf... |
2345 2346 2347 2348 2349 2350 2351 |
/* * could be 0 on HZ < 1000 setups */ if (!cfq_slice_async) cfq_slice_async = 1; if (!cfq_slice_idle) cfq_slice_idle = 1; |
1da177e4c Linux-2.6.12-rc2 |
2352 2353 2354 2355 |
if (cfq_slab_setup()) return -ENOMEM; ret = elv_register(&iosched_cfq); |
22e2c507c [PATCH] Update cf... |
2356 2357 |
if (ret) cfq_slab_kill(); |
1da177e4c Linux-2.6.12-rc2 |
2358 |
|
1da177e4c Linux-2.6.12-rc2 |
2359 2360 2361 2362 2363 |
return ret; } static void __exit cfq_exit(void) { |
1da177e4c Linux-2.6.12-rc2 |
2364 |
elv_unregister(&iosched_cfq); |
83521d3eb [PATCH] cfq-iosch... |
2365 |
cfq_slab_kill(); |
1da177e4c Linux-2.6.12-rc2 |
2366 2367 2368 2369 2370 2371 2372 2373 |
} module_init(cfq_init); module_exit(cfq_exit); MODULE_AUTHOR("Jens Axboe"); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("Completely Fair Queueing IO scheduler"); |