diff options
Diffstat (limited to 'block')
| -rw-r--r-- | block/cfq-iosched.c | 871 | ||||
| -rw-r--r-- | block/elevator.c | 24 | ||||
| -rw-r--r-- | block/genhd.c | 14 | ||||
| -rw-r--r-- | block/ll_rw_blk.c | 7 |
4 files changed, 471 insertions, 445 deletions
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index b6491c020f26..64df3fa303b0 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -9,7 +9,6 @@ #include <linux/module.h> #include <linux/blkdev.h> #include <linux/elevator.h> -#include <linux/hash.h> #include <linux/rbtree.h> #include <linux/ioprio.h> @@ -26,19 +25,17 @@ static int cfq_slice_async = HZ / 25; static const int cfq_slice_async_rq = 2; static int cfq_slice_idle = HZ / 125; +/* + * grace period before allowing idle class to get disk access + */ #define CFQ_IDLE_GRACE (HZ / 10) -#define CFQ_SLICE_SCALE (5) - -#define CFQ_KEY_ASYNC (0) /* - * for the hash of cfqq inside the cfqd + * below this threshold, we consider thinktime immediate */ -#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) +#define CFQ_MIN_TT (2) -#define list_entry_cfqq(ptr) list_entry((ptr), struct cfq_queue, cfq_list) +#define CFQ_SLICE_SCALE (5) #define RQ_CIC(rq) ((struct cfq_io_context*)(rq)->elevator_private) #define RQ_CFQQ(rq) ((rq)->elevator_private2) @@ -56,17 +53,21 @@ static struct completion *ioc_gone; #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]) - #define sample_valid(samples) ((samples) > 80) /* + * Most of our rbtree usage is for sorting with min extraction, so + * if we cache the leftmost node we don't have to walk down the tree + * to find it. Idea borrowed from Ingo Molnars CFS scheduler. We should + * move this into the elevator for the rq sorting as well. + */ +struct cfq_rb_root { + struct rb_root rb; + struct rb_node *left; +}; +#define CFQ_RB_ROOT (struct cfq_rb_root) { RB_ROOT, NULL, } + +/* * Per block device queue structure */ struct cfq_data { @@ -75,18 +76,11 @@ struct cfq_data { /* * 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; + struct cfq_rb_root service_tree; unsigned int busy_queues; - /* - * cfqq lookup hash - */ - struct hlist_head *cfq_hash; - int rq_in_driver; + int sync_flight; int hw_tag; /* @@ -97,12 +91,10 @@ struct cfq_data { 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; - sector_t last_sector; + sector_t last_position; unsigned long last_end_request; /* @@ -117,6 +109,9 @@ struct cfq_data { unsigned int cfq_slice_idle; struct list_head cic_list; + + sector_t new_seek_mean; + u64 new_seek_total; }; /* @@ -127,12 +122,10 @@ struct cfq_queue { atomic_t ref; /* parent cfq_data */ struct cfq_data *cfqd; - /* cfqq lookup hash */ - struct hlist_node cfq_hash; - /* hash key */ - unsigned int key; - /* member of the rr/busy/cur/idle cfqd list */ - struct list_head cfq_list; + /* service_tree member */ + struct rb_node rb_node; + /* service_tree key */ + unsigned long rb_key; /* sorted list of pending requests */ struct rb_root sort_list; /* if fifo isn't expired, next request to serve */ @@ -147,11 +140,10 @@ struct cfq_queue { struct list_head fifo; unsigned long slice_end; - unsigned long service_last; long slice_resid; - /* number of requests that are on the dispatch list */ - int on_dispatch[2]; + /* number of requests that are on the dispatch list or inside driver */ + int dispatched; /* io prio of this group */ unsigned short ioprio, org_ioprio; @@ -159,6 +151,8 @@ struct cfq_queue { /* various state flags, see below */ unsigned int flags; + + sector_t last_request_pos; }; enum cfqq_state_flags { @@ -172,6 +166,7 @@ enum cfqq_state_flags { CFQ_CFQQ_FLAG_prio_changed, /* task priority has changed */ CFQ_CFQQ_FLAG_queue_new, /* queue never been serviced */ CFQ_CFQQ_FLAG_slice_new, /* no requests dispatched in slice */ + CFQ_CFQQ_FLAG_sync, /* synchronous queue */ }; #define CFQ_CFQQ_FNS(name) \ @@ -198,11 +193,38 @@ CFQ_CFQQ_FNS(idle_window); CFQ_CFQQ_FNS(prio_changed); CFQ_CFQQ_FNS(queue_new); CFQ_CFQQ_FNS(slice_new); +CFQ_CFQQ_FNS(sync); #undef CFQ_CFQQ_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 request *); -static struct cfq_queue *cfq_get_queue(struct cfq_data *cfqd, unsigned int key, struct task_struct *tsk, gfp_t gfp_mask); +static struct cfq_queue *cfq_get_queue(struct cfq_data *, int, + struct task_struct *, gfp_t); +static struct cfq_io_context *cfq_cic_rb_lookup(struct cfq_data *, + struct io_context *); + +static inline struct cfq_queue *cic_to_cfqq(struct cfq_io_context *cic, + int is_sync) +{ + return cic->cfqq[!!is_sync]; +} + +static inline void cic_set_cfqq(struct cfq_io_context *cic, + struct cfq_queue *cfqq, int is_sync) +{ + cic->cfqq[!!is_sync] = cfqq; +} + +/* + * We regard a request as SYNC, if it's either a read or has the SYNC bit + * set (in which case it could also be direct WRITE). + */ +static inline int cfq_bio_sync(struct bio *bio) +{ + if (bio_data_dir(bio) == READ || bio_sync(bio)) + return 1; + + return 0; +} /* * scheduler run of queue, if there are requests pending and no one in the @@ -221,44 +243,31 @@ static int cfq_queue_empty(request_queue_t *q) return !cfqd->busy_queues; } -static inline pid_t cfq_queue_pid(struct task_struct *task, int rw, int is_sync) -{ - /* - * Use the per-process queue, for read requests and syncronous writes - */ - if (!(rw & REQ_RW) || is_sync) - return task->pid; - - return CFQ_KEY_ASYNC; -} - /* * 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. */ -static inline int -cfq_prio_to_slice(struct cfq_data *cfqd, struct cfq_queue *cfqq) +static inline int cfq_prio_slice(struct cfq_data *cfqd, int sync, + unsigned short prio) { - const int base_slice = cfqd->cfq_slice[cfq_cfqq_sync(cfqq)]; + const int base_slice = cfqd->cfq_slice[sync]; - WARN_ON(cfqq->ioprio >= IOPRIO_BE_NR); + WARN_ON(prio >= IOPRIO_BE_NR); + + return base_slice + (base_slice/CFQ_SLICE_SCALE * (4 - prio)); +} - return base_slice + (base_slice/CFQ_SLICE_SCALE * (4 - cfqq->ioprio)); +static inline int +cfq_prio_to_slice(struct cfq_data *cfqd, struct cfq_queue *cfqq) +{ + return cfq_prio_slice(cfqd, cfq_cfqq_sync(cfqq), cfqq->ioprio); } static inline void cfq_set_prio_slice(struct cfq_data *cfqd, struct cfq_queue *cfqq) { cfqq->slice_end = cfq_prio_to_slice(cfqd, cfqq) + jiffies; - cfqq->slice_end += cfqq->slice_resid; - - /* - * Don't carry over residual for more than one slice, we only want - * to slightly correct the fairness. Carrying over forever would - * easily introduce oscillations. - */ - cfqq->slice_resid = 0; } /* @@ -307,7 +316,7 @@ cfq_choose_req(struct cfq_data *cfqd, struct request *rq1, struct request *rq2) s1 = rq1->sector; s2 = rq2->sector; - last = cfqd->last_sector; + last = cfqd->last_position; /* * by definition, 1KiB is 2 sectors @@ -372,6 +381,26 @@ cfq_choose_req(struct cfq_data *cfqd, struct request *rq1, struct request *rq2) } /* + * The below is leftmost cache rbtree addon + */ +static struct rb_node *cfq_rb_first(struct cfq_rb_root *root) +{ + if (!root->left) + root->left = rb_first(&root->rb); + + return root->left; +} + +static void cfq_rb_erase(struct rb_node *n, struct cfq_rb_root *root) +{ + if (root->left == n) + root->left = NULL; + + rb_erase(n, &root->rb); + RB_CLEAR_NODE(n); +} + +/* * would be nice to take fifo expire time into account as well */ static struct request * @@ -398,78 +427,96 @@ cfq_find_next_rq(struct cfq_data *cfqd, struct cfq_queue *cfqq, return cfq_choose_req(cfqd, next, prev); } -static void cfq_resort_rr_list(struct cfq_queue *cfqq, int preempted) +static unsigned long cfq_slice_offset(struct cfq_data *cfqd, + struct cfq_queue *cfqq) { - struct cfq_data *cfqd = cfqq->cfqd; - struct list_head *list, *n; - struct cfq_queue *__cfqq; - /* - * Resorting requires the cfqq to be on the RR list already. + * just an approximation, should be ok. */ - if (!cfq_cfqq_on_rr(cfqq)) - return; + return (cfqd->busy_queues - 1) * (cfq_prio_slice(cfqd, 1, 0) - + cfq_prio_slice(cfqd, cfq_cfqq_sync(cfqq), cfqq->ioprio)); +} - list_del(&cfqq->cfq_list); +/* + * The cfqd->service_tree holds all pending cfq_queue's that have + * requests waiting to be processed. It is sorted in the order that + * we will service the queues. + */ +static void cfq_service_tree_add(struct cfq_data *cfqd, + struct cfq_queue *cfqq, int add_front) +{ + struct rb_node **p = &cfqd->service_tree.rb.rb_node; + struct rb_node *parent = NULL; + unsigned long rb_key; + int left; + + if (!add_front) { + rb_key = cfq_slice_offset(cfqd, cfqq) + jiffies; + rb_key += cfqq->slice_resid; + cfqq->slice_resid = 0; + } else + rb_key = 0; - if (cfq_class_rt(cfqq)) - list = &cfqd->cur_rr; - else if (cfq_class_idle(cfqq)) - list = &cfqd->idle_rr; - else { + if (!RB_EMPTY_NODE(&cfqq->rb_node)) { /* - * 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 + * same position, nothing more to do */ - if (cfq_cfqq_dispatched(cfqq)) - list = &cfqd->busy_rr; - else - list = &cfqd->rr_list[cfqq->ioprio]; + if (rb_key == cfqq->rb_key) + return; + + cfq_rb_erase(&cfqq->rb_node, &cfqd->service_tree); } - if (preempted || cfq_cfqq_queue_new(cfqq)) { - /* - * If this queue was preempted or is new (never been serviced), - * let it be added first for fairness but beind other new - * queues. - */ - n = list; - while (n->next != list) { - __cfqq = list_entry_cfqq(n->next); - if (!cfq_cfqq_queue_new(__cfqq)) - break; + left = 1; + while (*p) { + struct cfq_queue *__cfqq; + struct rb_node **n; + + parent = *p; + __cfqq = rb_entry(parent, struct cfq_queue, rb_node); - n = n->next; - } - list_add_tail(&cfqq->cfq_list, n); - } else if (!cfq_cfqq_class_sync(cfqq)) { - /* - * async queue always goes to the end. this wont be overly - * unfair to writes, as the sort of the sync queue wont be - * allowed to pass the async queue again. - */ - list_add_tail(&cfqq->cfq_list, list); - } else { /* - * sort by last service, but don't cross a new or async - * queue. we don't cross a new queue because it hasn't been - * service before, and we don't cross an async queue because - * it gets added to the end on expire. + * sort RT queues first, we always want to give + * preference to them. IDLE queues goes to the back. + * after that, sort on the next service time. */ - n = list; - while ((n = n->prev) != list) { - struct cfq_queue *__cfqq = list_entry_cfqq(n); + if (cfq_class_rt(cfqq) > cfq_class_rt(__cfqq)) + n = &(*p)->rb_left; + else if (cfq_class_rt(cfqq) < cfq_class_rt(__cfqq)) + n = &(*p)->rb_right; + else if (cfq_class_idle(cfqq) < cfq_class_idle(__cfqq)) + n = &(*p)->rb_left; + else if (cfq_class_idle(cfqq) > cfq_class_idle(__cfqq)) + n = &(*p)->rb_right; + else if (rb_key < __cfqq->rb_key) + n = &(*p)->rb_left; + else + n = &(*p)->rb_right; - if (!cfq_cfqq_class_sync(cfqq) || !__cfqq->service_last) - break; - if (time_before(__cfqq->service_last, cfqq->service_last)) - break; - } - list_add(&cfqq->cfq_list, n); + if (n == &(*p)->rb_right) + left = 0; + + p = n; } + + if (left) + cfqd->service_tree.left = &cfqq->rb_node; + + cfqq->rb_key = rb_key; + rb_link_node(&cfqq->rb_node, parent, p); + rb_insert_color(&cfqq->rb_node, &cfqd->service_tree.rb); +} + +/* + * Update cfqq's position in the service tree. + */ +static void cfq_resort_rr_list(struct cfq_data *cfqd, struct cfq_queue *cfqq) +{ + /* + * Resorting requires the cfqq to be on the RR list already. + */ + if (cfq_cfqq_on_rr(cfqq)) + cfq_service_tree_add(cfqd, cfqq, 0); } /* @@ -483,15 +530,21 @@ cfq_add_cfqq_rr(struct cfq_data *cfqd, struct cfq_queue *cfqq) cfq_mark_cfqq_on_rr(cfqq); cfqd->busy_queues++; - cfq_resort_rr_list(cfqq, 0); + cfq_resort_rr_list(cfqd, cfqq); } +/* + * Called when the cfqq no longer has requests pending, remove it from + * the service tree. + */ static inline void 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_del_init(&cfqq->cfq_list); + + if (!RB_EMPTY_NODE(&cfqq->rb_node)) + cfq_rb_erase(&cfqq->rb_node, &cfqd->service_tree); BUG_ON(!cfqd->busy_queues); cfqd->busy_queues--; @@ -532,6 +585,12 @@ static void cfq_add_rq_rb(struct request *rq) if (!cfq_cfqq_on_rr(cfqq)) cfq_add_cfqq_rr(cfqd, cfqq); + + /* + * 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); } static inline void @@ -546,10 +605,14 @@ static struct request * 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), bio_sync(bio)); + struct cfq_io_context *cic; struct cfq_queue *cfqq; - cfqq = cfq_find_cfq_hash(cfqd, key, tsk->ioprio); + cic = cfq_cic_rb_lookup(cfqd, tsk->io_context); + if (!cic) + return NULL; + + cfqq = cic_to_cfqq(cic, cfq_bio_sync(bio)); if (cfqq) { sector_t sector = bio->bi_sector + bio_sectors(bio); @@ -573,6 +636,8 @@ static void cfq_activate_request(request_queue_t *q, struct request *rq) */ if (!cfqd->hw_tag && cfqd->rq_in_driver > 4) cfqd->hw_tag = 1; + + cfqd->last_position = rq->hard_sector + rq->hard_nr_sectors; } static void cfq_deactivate_request(request_queue_t *q, struct request *rq) @@ -599,8 +664,7 @@ static void cfq_remove_request(struct request *rq) } } -static int -cfq_merge(request_queue_t *q, struct request **req, struct bio *bio) +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; @@ -642,23 +706,24 @@ static int cfq_allow_merge(request_queue_t *q, struct request *rq, struct bio *bio) { struct cfq_data *cfqd = q->elevator->elevator_data; - const int rw = bio_data_dir(bio); + struct cfq_io_context *cic; struct cfq_queue *cfqq; - pid_t key; /* * Disallow merge of a sync bio into an async request. */ - if ((bio_data_dir(bio) == READ || bio_sync(bio)) && !rq_is_sync(rq)) + if (cfq_bio_sync(bio) && !rq_is_sync(rq)) return 0; /* * Lookup the cfqq that this bio will be queued with. Allow * merge only if rq is queued there. */ - key = cfq_queue_pid(current, rw, bio_sync(bio)); - cfqq = cfq_find_cfq_hash(cfqd, key, current->ioprio); + cic = cfq_cic_rb_lookup(cfqd, current->io_context); + if (!cic) + return 0; + cfqq = cic_to_cfqq(cic, cfq_bio_sync(bio)); if (cfqq == RQ_CFQQ(rq)) return 1; @@ -678,6 +743,7 @@ __cfq_set_active_queue(struct cfq_data *cfqd, struct cfq_queue *cfqq) cfq_clear_cfqq_must_alloc_slice(cfqq); cfq_clear_cfqq_fifo_expire(cfqq); cfq_mark_cfqq_slice_new(cfqq); + cfq_clear_cfqq_queue_new(cfqq); } cfqd->active_queue = cfqq; @@ -688,23 +754,21 @@ __cfq_set_active_queue(struct cfq_data *cfqd, struct cfq_queue *cfqq) */ static void __cfq_slice_expired(struct cfq_data *cfqd, struct cfq_queue *cfqq, - int preempted, int timed_out) + int timed_out) { if (cfq_cfqq_wait_request(cfqq)) del_timer(&cfqd->idle_slice_timer); 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 - * or was preempted + * store what was left of this slice, if the queue idled/timed out */ if (timed_out && !cfq_cfqq_slice_new(cfqq)) cfqq->slice_resid = cfqq->slice_end - jiffies; - cfq_resort_rr_list(cfqq, preempted); + cfq_resort_rr_list(cfqd, cfqq); if (cfqq == cfqd->active_queue) cfqd->active_queue = NULL; @@ -713,163 +777,152 @@ __cfq_slice_expired(struct cfq_data *cfqd, struct cfq_queue *cfqq, put_io_context(cfqd->active_cic->ioc); cfqd->active_cic = NULL; } - - cfqd->dispatch_slice = 0; } -static inline void cfq_slice_expired(struct cfq_data *cfqd, int preempted, - int timed_out) +static inline void cfq_slice_expired(struct cfq_data *cfqd, int timed_out) { struct cfq_queue *cfqq = cfqd->active_queue; if (cfqq) - __cfq_slice_expired(cfqd, cfqq, preempted, timed_out); + __cfq_slice_expired(cfqd, cfqq, timed_out); } /* - * 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 + * Get next queue for service. Unless we have a queue preemption, + * we'll simply select the first cfqq in the service tree. */ -static int cfq_get_next_prio_level(struct cfq_data *cfqd) +static struct cfq_queue *cfq_get_next_queue(struct cfq_data *cfqd) { - int prio, wrap; + struct cfq_queue *cfqq; + struct rb_node *n; - prio = -1; - wrap = 0; - do { - int p; + if (RB_EMPTY_ROOT(&cfqd->service_tree.rb)) + return NULL; - for (p = cfqd->cur_prio; p <= cfqd->cur_end_prio; p++) { - if (!list_empty(&cfqd->rr_list[p])) { - prio = p; - break; - } - } + n = cfq_rb_first(&cfqd->service_tree); + cfqq = rb_entry(n, struct cfq_queue, rb_node); - 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; - } - } while (1); + if (cfq_class_idle(cfqq)) { + unsigned long end; - if (unlikely(prio == -1)) - return -1; + /* + * 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 + */ + end = cfqd->last_end_request + CFQ_IDLE_GRACE; + if (time_before(jiffies, end)) { + mod_timer(&cfqd->idle_class_timer, end); + cfqq = NULL; + } + } - BUG_ON(prio >= CFQ_PRIO_LISTS); + return cfqq; +} - list_splice_init(&cfqd->rr_list[prio], &cfqd->cur_rr); +/* + * Get and set a new active queue for service. + */ +static struct cfq_queue *cfq_set_active_queue(struct cfq_data *cfqd) +{ + struct cfq_queue *cfqq; - 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; - } + cfqq = cfq_get_next_queue(cfqd); + __cfq_set_active_queue(cfqd, cfqq); + return cfqq; +} - return prio; +static inline sector_t cfq_dist_from_last(struct cfq_data *cfqd, + struct request *rq) +{ + if (rq->sector >= cfqd->last_position) + return rq->sector - cfqd->last_position; + else + return cfqd->last_position - rq->sector; } -static struct cfq_queue *cfq_set_active_queue(struct cfq_data *cfqd) +static inline int cfq_rq_close(struct cfq_data *cfqd, struct request *rq) { - struct cfq_queue *cfqq = NULL; + struct cfq_io_context *cic = cfqd->active_cic; - 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); - } 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); - } 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 (!sample_valid(cic->seek_samples)) + return 0; - if (time_after_eq(jiffies, end)) - cfqq = list_entry_cfqq(cfqd->idle_rr.next); - else - mod_timer(&cfqd->idle_class_timer, end); - } + return cfq_dist_from_last(cfqd, rq) <= cic->seek_mean; +} - __cfq_set_active_queue(cfqd, cfqq); - return cfqq; +static int cfq_close_cooperator(struct cfq_data *cfq_data, + struct cfq_queue *cfqq) +{ + /* + * We should notice if some of the queues are cooperating, eg + * working closely on the same area of the disk. In that case, + * we can group them together and don't waste time idling. + */ + return 0; } -#define CIC_SEEKY(cic) ((cic)->seek_mean > (128 * 1024)) +#define CIC_SEEKY(cic) ((cic)->seek_mean > (8 * 1024)) -static int cfq_arm_slice_timer(struct cfq_data *cfqd) +static void cfq_arm_slice_timer(struct cfq_data *cfqd) { struct cfq_queue *cfqq = cfqd->active_queue; struct cfq_io_context *cic; unsigned long sl; WARN_ON(!RB_EMPTY_ROOT(&cfqq->sort_list)); + WARN_ON(cfq_cfqq_slice_new(cfqq)); /* * idle is disabled, either manually or by past process history */ - if (!cfqd->cfq_slice_idle) - return 0; - if (!cfq_cfqq_idle_window(cfqq)) - return 0; + if (!cfqd->cfq_slice_idle || !cfq_cfqq_idle_window(cfqq)) + return; + /* * task has exited, don't wait */ cic = cfqd->active_cic; if (!cic || !cic->ioc->task) - return 0; + return; + + /* + * See if this prio level has a good candidate + */ + if (cfq_close_cooperator(cfqd, cfqq) && + (sample_valid(cic->ttime_samples) && cic->ttime_mean > 2)) + return; cfq_mark_cfqq_must_dispatch(cfqq); cfq_mark_cfqq_wait_request(cfqq); - sl = min(cfqq->slice_end - 1, (unsigned long) cfqd->cfq_slice_idle); - /* * we don't want to idle for seeks, but we do want to allow * 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 */ + sl = cfqd->cfq_slice_idle; if (sample_valid(cic->seek_samples) && CIC_SEEKY(cic)) - sl = min(sl, msecs_to_jiffies(2)); + sl = min(sl, msecs_to_jiffies(CFQ_MIN_TT)); mod_timer(&cfqd->idle_slice_timer, jiffies + sl); - return 1; } +/* + * Move request from internal lists to the request queue dispatch list. + */ static void cfq_dispatch_insert(request_queue_t *q, struct request *rq) { struct cfq_data *cfqd = q->elevator->elevator_data; struct cfq_queue *cfqq = RQ_CFQQ(rq); cfq_remove_request(rq); - cfqq->on_dispatch[rq_is_sync(rq)]++; + cfqq->dispatched++; elv_dispatch_sort(q, rq); - rq = list_entry(q->queue_head.prev, struct request, queuelist); - cfqd->last_sector = rq->sector + rq->nr_sectors; + if (cfq_cfqq_sync(cfqq)) + cfqd->sync_flight++; } /* @@ -889,13 +942,13 @@ static inline struct request *cfq_check_fifo(struct cfq_queue *cfqq) if (list_empty(&cfqq->fifo)) return NULL; - fifo = cfq_cfqq_class_sync(cfqq); + fifo = cfq_cfqq_sync(cfqq); rq = rq_entry_fifo(cfqq->fifo.next); - if (time_after(jiffies, rq->start_time + cfqd->cfq_fifo_expire[fifo])) - return rq; + if (time_before(jiffies, rq->start_time + cfqd->cfq_fifo_expire[fifo])) + return NULL; - return NULL; + return rq; } static inline int @@ -909,7 +962,8 @@ cfq_prio_to_maxrq(struct cfq_data *cfqd, struct cfq_queue *cfqq) } /* - * get next queue for service + * Select a queue for service. If we have a current active queue, + * check whether to continue servicing it, or retrieve and set a new one. */ static struct cfq_queue *cfq_select_queue(struct cfq_data *cfqd) { @@ -920,33 +974,41 @@ static struct cfq_queue *cfq_select_queue(struct cfq_data *cfqd) goto new_queue; /* - * slice has expired + * The active queue has run out of time, expire it and select new. */ - if (!cfq_cfqq_must_dispatch(cfqq) && cfq_slice_used(cfqq)) + if (cfq_slice_used(cfqq)) goto expire; /* - * if queue has requests, dispatch one. if not, check if - * enough slice is left to wait for one + * The active queue has requests and isn't expired, allow it to + * dispatch. */ if (!RB_EMPTY_ROOT(&cfqq->sort_list)) goto keep_queue; - else if (cfq_cfqq_slice_new(cfqq) || cfq_cfqq_dispatched(cfqq)) { + + /* + * No requests pending. If the active queue still has requests in + * flight or is idling for a new request, allow either of these + * conditions to happen (or time out) before selecting a new queue. + */ + if (timer_pending(&cfqd->idle_slice_timer) || + (cfqq->dispatched && cfq_cfqq_idle_window(cfqq))) { cfqq = NULL; goto keep_queue; - } else if (cfq_cfqq_class_sync(cfqq)) { - if (cfq_arm_slice_timer(cfqd)) - return NULL; } expire: - cfq_slice_expired(cfqd, 0, 0); + cfq_slice_expired(cfqd, 0); new_queue: cfqq = cfq_set_active_queue(cfqd); keep_queue: return cfqq; } +/* + * Dispatch some requests from cfqq, moving them to the request queue + * dispatch list. + */ static int __cfq_dispatch_requests(struct cfq_data *cfqd, struct cfq_queue *cfqq, int max_dispatch) @@ -969,7 +1031,6 @@ __cfq_dispatch_requests(struct cfq_data *cfqd, struct cfq_queue *cfqq, */ cfq_dispatch_insert(cfqd->queue, rq); - cfqd->dispatch_slice++; dispatched++; if (!cfqd->active_cic) { @@ -986,58 +1047,55 @@ __cfq_dispatch_requests(struct cfq_data *cfqd, struct cfq_queue *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)) { + if (cfqd->busy_queues > 1 && ((!cfq_cfqq_sync(cfqq) && + dispatched >= cfq_prio_to_maxrq(cfqd, cfqq)) || + cfq_class_idle(cfqq))) { cfqq->slice_end = jiffies + 1; - cfq_slice_expired(cfqd, 0, 0); + cfq_slice_expired(cfqd, 0); } return dispatched; } -static int -cfq_forced_dispatch_cfqqs(struct list_head *list) +static inline int __cfq_forced_dispatch_cfqq(struct cfq_queue *cfqq) { - struct cfq_queue *cfqq, *next; - int dispatched; + int dispatched = 0; - dispatched = 0; - list_for_each_entry_safe(cfqq, next, list, cfq_list) { - while (cfqq->next_rq) { - cfq_dispatch_insert(cfqq->cfqd->queue, cfqq->next_rq); - dispatched++; - } - BUG_ON(!list_empty(&cfqq->fifo)); + while (cfqq->next_rq) { + cfq_dispatch_insert(cfqq->cfqd->queue, cfqq->next_rq); + dispatched++; } + BUG_ON(!list_empty(&cfqq->fifo)); return dispatched; } -static int -cfq_forced_dispatch(struct cfq_data *cfqd) +/* + * Drain our current requests. Used for barriers and when switching + * io schedulers on-the-fly. + */ +static int cfq_forced_dispatch(struct cfq_data *cfqd) { - int i, dispatched = 0; + int dispatched = 0; + struct rb_node *n; - for (i = 0; i < CFQ_PRIO_LISTS; i++) - dispatched += cfq_forced_dispatch_cfqqs(&cfqd->rr_list[i]); + while ((n = cfq_rb_first(&cfqd->service_tree)) != NULL) { + struct cfq_queue *cfqq = rb_entry(n, struct cfq_queue, rb_node); - dispatched += cfq_forced_dispatch_cfqqs(&cfqd->busy_rr); - dispatched += cfq_forced_dispatch_cfqqs(&cfqd->cur_rr); - dispatched += cfq_forced_dispatch_cfqqs(&cfqd->idle_rr); + dispatched += __cfq_forced_dispatch_cfqq(cfqq); + } - cfq_slice_expired(cfqd, 0, 0); + cfq_slice_expired(cfqd, 0); BUG_ON(cfqd->busy_queues); return dispatched; } -static int -cfq_dispatch_requests(request_queue_t *q, int force) +static int cfq_dispatch_requests(request_queue_t *q, int force) { struct cfq_data *cfqd = q->elevator->elevator_data; - struct cfq_queue *cfqq, *prev_cfqq; + struct cfq_queue *cfqq; int dispatched; if (!cfqd->busy_queues) @@ -1047,34 +1105,28 @@ cfq_dispatch_requests(request_queue_t *q, int force) return cfq_forced_dispatch(cfqd); 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; + max_dispatch = cfqd->cfq_quantum; + if (cfq_class_idle(cfqq)) + max_dispatch = 1; - /* - * So we have dispatched before in this round, if the - * next queue has idling enabled (must be sync), don't - * allow it service until the previous have continued. - */ - if (cfqd->rq_in_driver && cfq_cfqq_idle_window(cfqq)) + if (cfqq->dispatched >= max_dispatch) { + if (cfqd->busy_queues > 1) + break; + if (cfqq->dispatched >= 4 * max_dispatch) + break; + } + + if (cfqd->sync_flight && !cfq_cfqq_sync(cfqq)) break; cfq_clear_cfqq_must_dispatch(cfqq); cfq_clear_cfqq_wait_request(cfqq); del_timer(&cfqd->idle_slice_timer); - max_dispatch = cfqd->cfq_quantum; - if (cfq_class_idle(cfqq)) - max_dispatch = 1; - dispatched += __cfq_dispatch_requests(cfqd, cfqq, max_dispatch); - prev_cfqq = cfqq; } return dispatched; @@ -1100,48 +1152,21 @@ static void cfq_put_queue(struct cfq_queue *cfqq) BUG_ON(cfq_cfqq_on_rr(cfqq)); if (unlikely(cfqd->active_queue == cfqq)) { - __cfq_slice_expired(cfqd, cfqq, 0, 0); + __cfq_slice_expired(cfqd, cfqq, 0); cfq_schedule_dispatch(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 struct cfq_queue * -__cfq_find_cfq_hash(struct cfq_data *cfqd, unsigned int key, unsigned int prio, - const int hashval) -{ - struct hlist_head *hash_list = &cfqd->cfq_hash[hashval]; - struct hlist_node *entry; - struct cfq_queue *__cfqq; - - hlist_for_each_entry(__cfqq, entry, hash_list, cfq_hash) { - const unsigned short __p = IOPRIO_PRIO_VALUE(__cfqq->org_ioprio_class, __cfqq->org_ioprio); - - if (__cfqq->key == key && (__p == prio || !prio)) - return __cfqq; - } - - return NULL; -} - -static struct cfq_queue * -cfq_find_cfq_hash(struct cfq_data *cfqd, unsigned int key, unsigned short prio) -{ - return __cfq_find_cfq_hash(cfqd, key, prio, hash_long(key, CFQ_QHASH_SHIFT)); -} - static void cfq_free_io_context(struct io_context *ioc) { struct cfq_io_context *__cic; struct rb_node *n; int freed = 0; + ioc->ioc_data = NULL; + while ((n = rb_first(&ioc->cic_root)) != NULL) { __cic = rb_entry(n, struct cfq_io_context, rb_node); rb_erase(&__cic->rb_node, &ioc->cic_root); @@ -1158,7 +1183,7 @@ static void cfq_free_io_context(struct io_context *ioc) static void cfq_exit_cfqq(struct cfq_data *cfqd, struct cfq_queue *cfqq) { if (unlikely(cfqq == cfqd->active_queue)) { - __cfq_slice_expired(cfqd, cfqq, 0, 0); + __cfq_slice_expired(cfqd, cfqq, 0); cfq_schedule_dispatch(cfqd); } @@ -1183,10 +1208,6 @@ static void __cfq_exit_single_io_context(struct cfq_data *cfqd, } } - -/* - * Called with interrupts disabled - */ static void cfq_exit_single_io_context(struct cfq_io_context *cic) { struct cfq_data *cfqd = cic->key; @@ -1200,15 +1221,20 @@ static void cfq_exit_single_io_context(struct cfq_io_context *cic) } } +/* + * The process that ioc belongs to has exited, we need to clean up + * and put the internal structures we have that belongs to that process. + */ static void cfq_exit_io_context(struct io_context *ioc) { struct cfq_io_context *__cic; struct rb_node *n; + ioc->ioc_data = NULL; + /* * put the reference this task is holding to the various queues */ - n = rb_first(&ioc->cic_root); while (n != NULL) { __cic = rb_entry(n, struct cfq_io_context, rb_node); @@ -1276,8 +1302,6 @@ static void cfq_init_prio_data(struct cfq_queue *cfqq) */ cfqq->org_ioprio = cfqq->ioprio; cfqq->org_ioprio_class = cfqq->ioprio_class; - - cfq_resort_rr_list(cfqq, 0); cfq_clear_cfqq_prio_changed(cfqq); } @@ -1295,7 +1319,7 @@ static inline void changed_ioprio(struct cfq_io_context *cic) cfqq = cic->cfqq[ASYNC]; if (cfqq) { struct cfq_queue *new_cfqq; - new_cfqq = cfq_get_queue(cfqd, CFQ_KEY_ASYNC, cic->ioc->task, + new_cfqq = cfq_get_queue(cfqd, ASYNC, cic->ioc->task, GFP_ATOMIC); if (new_cfqq) { cic->cfqq[ASYNC] = new_cfqq; @@ -1327,16 +1351,16 @@ static void cfq_ioc_set_ioprio(struct io_context *ioc) } static struct cfq_queue * -cfq_get_queue(struct cfq_data *cfqd, unsigned int key, struct task_struct *tsk, +cfq_get_queue(struct cfq_data *cfqd, int is_sync, struct task_struct *tsk, gfp_t gfp_mask) { - const int hashval = hash_long(key, CFQ_QHASH_SHIFT); struct cfq_queue *cfqq, *new_cfqq = NULL; - unsigned short ioprio; + struct cfq_io_context *cic; retry: - ioprio = tsk->ioprio; - cfqq = __cfq_find_cfq_hash(cfqd, key, ioprio, hashval); + cic = cfq_cic_rb_lookup(cfqd, tsk->io_context); + /* cic always exists here */ + cfqq = cic_to_cfqq(cic, is_sync); if (!cfqq) { if (new_cfqq) { @@ -1361,18 +1385,20 @@ retry: memset(cfqq, 0, sizeof(*cfqq)); - INIT_HLIST_NODE(&cfqq->cfq_hash); - INIT_LIST_HEAD(&cfqq->cfq_list); + RB_CLEAR_NODE(&cfqq->rb_node); 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; - cfq_mark_cfqq_idle_window(cfqq); + if (is_sync) { + cfq_mark_cfqq_idle_window(cfqq); + cfq_mark_cfqq_sync(cfqq); + } + cfq_mark_cfqq_prio_changed(cfqq); cfq_mark_cfqq_queue_new(cfqq); + cfq_init_prio_data(cfqq); } @@ -1385,10 +1411,17 @@ out: return cfqq; } +/* + * We drop cfq io contexts lazily, so we may find a dead one. + */ static void cfq_drop_dead_cic(struct io_context *ioc, struct cfq_io_context *cic) { WARN_ON(!list_empty(&cic->queue_list)); + + if (ioc->ioc_data == cic) + ioc->ioc_data = NULL; + rb_erase(&cic->rb_node, &ioc->cic_root); kmem_cache_free(cfq_ioc_pool, cic); elv_ioc_count_dec(ioc_count); @@ -1401,6 +1434,16 @@ cfq_cic_rb_lookup(struct cfq_data *cfqd, struct io_context *ioc) struct cfq_io_context *cic; void *k, *key = cfqd; + if (unlikely(!ioc)) + return NULL; + + /* + * we maintain a last-hit cache, to avoid browsing over the tree + */ + cic = ioc->ioc_data; + if (cic && cic->key == cfqd) + return cic; + restart: n = ioc->cic_root.rb_node; while (n) { @@ -1416,8 +1459,10 @@ restart: n = n->rb_left; else if (key > k) n = n->rb_right; - else + else { + ioc->ioc_data = cic; return cic; + } } return NULL; @@ -1514,7 +1559,8 @@ cfq_update_io_thinktime(struct cfq_data *cfqd, struct cfq_io_context *cic) } static void -cfq_update_io_seektime(struct cfq_io_context *cic, struct request *rq) +cfq_update_io_seektime(struct cfq_data *cfqd, struct cfq_io_context *cic, + struct request *rq) { sector_t sdist; u64 total; @@ -1524,6 +1570,11 @@ cfq_update_io_seektime(struct cfq_io_context *cic, struct request *rq) else sdist = cic->last_request_pos - rq->sector; + if (!cic->seek_samples) { + cfqd->new_seek_total = (7*cic->seek_total + (u64)256*sdist) / 8; + cfqd->new_seek_mean = cfqd->new_seek_total / 256; + } + /* * Don't allow the seek distance to get too large from the * odd fragment, pagein, etc @@ -1548,7 +1599,12 @@ static void cfq_update_idle_window(struct cfq_data *cfqd, struct cfq_queue *cfqq, struct cfq_io_context *cic) { - int enable_idle = cfq_cfqq_idle_window(cfqq); + int enable_idle; + + if (!cfq_cfqq_sync(cfqq)) + return; + + enable_idle = cfq_cfqq_idle_window(cfqq); if (!cic->ioc->task || !cfqd->cfq_slice_idle || (cfqd->hw_tag && CIC_SEEKY(cic))) @@ -1574,24 +1630,28 @@ static int cfq_should_preempt(struct cfq_data *cfqd, struct cfq_queue *new_cfqq, struct request *rq) { - struct cfq_queue *cfqq = cfqd->active_queue; + struct cfq_queue *cfqq; - if (cfq_class_idle(new_cfqq)) + cfqq = cfqd->active_queue; + if (!cfqq) return 0; - if (!cfqq) + if (cfq_slice_used(cfqq)) + return 1; + + if (cfq_class_idle(new_cfqq)) return 0; if (cfq_class_idle(cfqq)) return 1; - if (!cfq_cfqq_wait_request(new_cfqq)) - return 0; + /* * 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. @@ -1599,6 +1659,16 @@ cfq_should_preempt(struct cfq_data *cfqd, struct cfq_queue *new_cfqq, if (rq_is_meta(rq) && !cfqq->meta_pending) return 1; + if (!cfqd->active_cic || !cfq_cfqq_wait_request(cfqq)) + return 0; + + /* + * if this request is as-good as one we would expect from the + * current cfqq, let it preempt + */ + if (cfq_rq_close(cfqd, rq)) + return 1; + return 0; } @@ -1608,14 +1678,15 @@ 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) { - cfq_slice_expired(cfqd, 1, 1); + cfq_slice_expired(cfqd, 1); /* * 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); + + cfq_service_tree_add(cfqd, cfqq, 1); cfqq->slice_end = 0; cfq_mark_cfqq_slice_new(cfqq); @@ -1634,34 +1705,12 @@ cfq_rq_enqueued(struct cfq_data *cfqd, struct cfq_queue *cfqq, if (rq_is_meta(rq)) cfqq->meta_pending++; - /* - * 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 (!rq_is_sync(rq)) { - /* - * sync process issued an async request, if it's waiting - * then expire it and kick rq handling. - */ - if (cic == cfqd->active_cic && - del_timer(&cfqd->idle_slice_timer)) { - cfq_slice_expired(cfqd, 0, 0); - blk_start_queueing(cfqd->queue); - } - return; - } - cfq_update_io_thinktime(cfqd, cic); - cfq_update_io_seektime(cic, rq); + cfq_update_io_seektime(cfqd, cic, rq); cfq_update_idle_window(cfqd, cfqq, cic); cic->last_request_pos = rq->sector + rq->nr_sectors; + cfqq->last_request_pos = cic->last_request_pos; if (cfqq == cfqd->active_queue) { /* @@ -1710,16 +1759,16 @@ static void cfq_completed_request(request_queue_t *q, struct request *rq) now = jiffies; WARN_ON(!cfqd->rq_in_driver); - WARN_ON(!cfqq->on_dispatch[sync]); + WARN_ON(!cfqq->dispatched); cfqd->rq_in_driver--; - cfqq->on_dispatch[sync]--; - cfqq->service_last = now; + cfqq->dispatched--; + + if (cfq_cfqq_sync(cfqq)) + cfqd->sync_flight--; if (!cfq_class_idle(cfqq)) cfqd->last_end_request = now; - cfq_resort_rr_list(cfqq, 0); - if (sync) RQ_CIC(rq)->last_end_request = now; @@ -1733,12 +1782,13 @@ static void cfq_completed_request(request_queue_t *q, struct request *rq) cfq_clear_cfqq_slice_new(cfqq); } if (cfq_slice_used(cfqq)) - cfq_slice_expired(cfqd, 0, 1); - else if (sync && RB_EMPTY_ROOT(&cfqq->sort_list)) { - if (!cfq_arm_slice_timer(cfqd)) - cfq_schedule_dispatch(cfqd); - } + cfq_slice_expired(cfqd, 1); + else if (sync && RB_EMPTY_ROOT(&cfqq->sort_list)) + cfq_arm_slice_timer(cfqd); } + + if (!cfqd->rq_in_driver) + cfq_schedule_dispatch(cfqd); } /* @@ -1747,9 +1797,6 @@ static void cfq_completed_request(request_queue_t *q, struct request *rq) */ static void cfq_prio_boost(struct cfq_queue *cfqq) { - const int ioprio_class = cfqq->ioprio_class; - const int ioprio = cfqq->ioprio; - if (has_fs_excl()) { /* * boost idle prio on transactions that would lock out other @@ -1768,12 +1815,6 @@ static void cfq_prio_boost(struct cfq_queue *cfqq) if (cfqq->ioprio != cfqq->org_ioprio) cfqq->ioprio = cfqq->org_ioprio; } - - /* - * refile between round-robin lists if we moved the priority class - */ - if ((ioprio_class != cfqq->ioprio_class || ioprio != cfqq->ioprio)) - cfq_resort_rr_list(cfqq, 0); } static inline int __cfq_may_queue(struct cfq_queue *cfqq) @@ -1791,10 +1832,8 @@ static int cfq_may_queue(request_queue_t *q, int rw) { struct cfq_data *cfqd = q->elevator->elevator_data; struct task_struct *tsk = current; + struct cfq_io_context *cic; struct cfq_queue *cfqq; - unsigned int key; - - key = cfq_queue_pid(tsk, rw, rw & REQ_RW_SYNC); /* * don't force setup of a queue from here, as a call to may_queue @@ -1802,7 +1841,11 @@ static int cfq_may_queue(request_queue_t *q, int rw) * so just lookup a possibly existing queue, or return 'may queue' * if that fails */ - cfqq = cfq_find_cfq_hash(cfqd, key, tsk->ioprio); + cic = cfq_cic_rb_lookup(cfqd, tsk->io_context); + if (!cic) + return ELV_MQUEUE_MAY; + + cfqq = cic_to_cfqq(cic, rw & REQ_RW_SYNC); if (cfqq) { cfq_init_prio_data(cfqq); cfq_prio_boost(cfqq); @@ -1846,7 +1889,6 @@ cfq_set_request(request_queue_t *q, struct request *rq, gfp_t gfp_mask) struct cfq_io_context *cic; const int rw = rq_data_dir(rq); const int is_sync = rq_is_sync(rq); - pid_t key = cfq_queue_pid(tsk, rw, is_sync); struct cfq_queue *cfqq; unsigned long flags; @@ -1859,14 +1901,15 @@ cfq_set_request(request_queue_t *q, struct request *rq, gfp_t gfp_mask) if (!cic) goto queue_fail; - if (!cic->cfqq[is_sync]) { - cfqq = cfq_get_queue(cfqd, key, tsk, gfp_mask); + cfqq = cic_to_cfqq(cic, is_sync); + if (!cfqq) { + cfqq = cfq_get_queue(cfqd, is_sync, tsk, gfp_mask); + if (!cfqq) goto queue_fail; - cic->cfqq[is_sync] = cfqq; - } else - cfqq = cic->cfqq[is_sync]; + cic_set_cfqq(cic, cfqq, is_sync); + } cfqq->allocated[rw]++; cfq_clear_cfqq_must_alloc(cfqq); @@ -1936,7 +1979,7 @@ static void cfq_idle_slice_timer(unsigned long data) } } expire: - cfq_slice_expired(cfqd, 0, timed_out); + cfq_slice_expired(cfqd, timed_out); out_kick: cfq_schedule_dispatch(cfqd); out_cont: @@ -1982,7 +2025,7 @@ static void cfq_exit_queue(elevator_t *e) spin_lock_irq(q->queue_lock); if (cfqd->active_queue) - __cfq_slice_expired(cfqd, cfqd->active_queue, 0, 0); + __cfq_slice_expired(cfqd, cfqd->active_queue, 0); while (!list_empty(&cfqd->cic_list)) { struct cfq_io_context *cic = list_entry(cfqd->cic_list.next, @@ -1996,14 +2039,12 @@ static void cfq_exit_queue(elevator_t *e) cfq_shutdown_timer_wq(cfqd); - kfree(cfqd->cfq_hash); kfree(cfqd); } static void *cfq_init_queue(request_queue_t *q) { struct cfq_data *cfqd; - int i; cfqd = kmalloc_node(sizeof(*cfqd), GFP_KERNEL, q->node); if (!cfqd) @@ -2011,21 +2052,9 @@ static void *cfq_init_queue(request_queue_t *q) memset(cfqd, 0, sizeof(*cfqd)); - 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); + cfqd->service_tree = CFQ_RB_ROOT; INIT_LIST_HEAD(&cfqd->cic_list); - cfqd->cfq_hash = kmalloc_node(sizeof(struct hlist_head) * CFQ_QHASH_ENTRIES, GFP_KERNEL, q->node); - if (!cfqd->cfq_hash) - goto out_free; - - for (i = 0; i < CFQ_QHASH_ENTRIES; i++) - INIT_HLIST_HEAD(&cfqd->cfq_hash[i]); - cfqd->queue = q; init_timer(&cfqd->idle_slice_timer); @@ -2049,9 +2078,6 @@ static void *cfq_init_queue(request_queue_t *q) cfqd->cfq_slice_idle = cfq_slice_idle; return cfqd; -out_free: - kfree(cfqd); - return NULL; } static void cfq_slab_kill(void) @@ -2083,7 +2109,6 @@ fail: /* * sysfs parts below --> */ - static ssize_t cfq_var_show(unsigned int var, char *page) { diff --git a/block/elevator.c b/block/elevator.c index 25f6ef28e3bb..ce866eb75f6a 100644 --- a/block/elevator.c +++ b/block/elevator.c @@ -134,13 +134,13 @@ static struct elevator_type *elevator_get(const char *name) { struct elevator_type *e; - spin_lock_irq(&elv_list_lock); + spin_lock(&elv_list_lock); e = elevator_find(name); if (e && !try_module_get(e->elevator_owner)) e = NULL; - spin_unlock_irq(&elv_list_lock); + spin_unlock(&elv_list_lock); return e; } @@ -964,17 +964,19 @@ void elv_unregister_queue(struct request_queue *q) int elv_register(struct elevator_type *e) { - spin_lock_irq(&elv_list_lock); + char *def = ""; + + spin_lock(&elv_list_lock); BUG_ON(elevator_find(e->elevator_name)); list_add_tail(&e->list, &elv_list); - spin_unlock_irq(&elv_list_lock); + spin_unlock(&elv_list_lock); - printk(KERN_INFO "io scheduler %s registered", e->elevator_name); if (!strcmp(e->elevator_name, chosen_elevator) || (!*chosen_elevator && !strcmp(e->elevator_name, CONFIG_DEFAULT_IOSCHED))) - printk(" (default)"); - printk("\n"); + def = " (default)"; + + printk(KERN_INFO "io scheduler %s registered%s\n", e->elevator_name, def); return 0; } EXPORT_SYMBOL_GPL(elv_register); @@ -997,9 +999,9 @@ void elv_unregister(struct elevator_type *e) read_unlock(&tasklist_lock); } - spin_lock_irq(&elv_list_lock); + spin_lock(&elv_list_lock); list_del_init(&e->list); - spin_unlock_irq(&elv_list_lock); + spin_unlock(&elv_list_lock); } EXPORT_SYMBOL_GPL(elv_unregister); @@ -1117,7 +1119,7 @@ ssize_t elv_iosched_show(request_queue_t *q, char *name) struct list_head *entry; int len = 0; - spin_lock_irq(&elv_list_lock); + spin_lock(&elv_list_lock); list_for_each(entry, &elv_list) { struct elevator_type *__e; @@ -1127,7 +1129,7 @@ ssize_t elv_iosched_show(request_queue_t *q, char *name) else len += sprintf(name+len, "%s ", __e->elevator_name); } - spin_unlock_irq(&elv_list_lock); + spin_unlock(&elv_list_lock); len += sprintf(len+name, "\n"); return len; diff --git a/block/genhd.c b/block/genhd.c index 050a1f0f3a86..b5664440896c 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -17,7 +17,7 @@ #include <linux/buffer_head.h> #include <linux/mutex.h> -struct subsystem block_subsys; +struct kset block_subsys; static DEFINE_MUTEX(block_subsys_lock); /* @@ -62,8 +62,6 @@ int register_blkdev(unsigned int major, const char *name) /* temporary */ if (major == 0) { for (index = ARRAY_SIZE(major_names)-1; index > 0; index--) { - if (is_lanana_major(index)) - continue; if (major_names[index] == NULL) break; } @@ -223,7 +221,7 @@ static void *part_start(struct seq_file *part, loff_t *pos) loff_t l = *pos; mutex_lock(&block_subsys_lock); - list_for_each(p, &block_subsys.kset.list) + list_for_each(p, &block_subsys.list) if (!l--) return list_entry(p, struct gendisk, kobj.entry); return NULL; @@ -233,7 +231,7 @@ static void *part_next(struct seq_file *part, void *v, loff_t *pos) { struct list_head *p = ((struct gendisk *)v)->kobj.entry.next; ++*pos; - return p==&block_subsys.kset.list ? NULL : + return p==&block_subsys.list ? NULL : list_entry(p, struct gendisk, kobj.entry); } @@ -248,7 +246,7 @@ static int show_partition(struct seq_file *part, void *v) int n; char buf[BDEVNAME_SIZE]; - if (&sgp->kobj.entry == block_subsys.kset.list.next) + if (&sgp->kobj.entry == block_subsys.list.next) seq_puts(part, "major minor #blocks name\n\n"); /* Don't show non-partitionable removeable devices or empty devices */ @@ -567,7 +565,7 @@ static void *diskstats_start(struct seq_file *part, loff_t *pos) struct list_head *p; mutex_lock(&block_subsys_lock); - list_for_each(p, &block_subsys.kset.list) + list_for_each(p, &block_subsys.list) if (!k--) return list_entry(p, struct gendisk, kobj.entry); return NULL; @@ -577,7 +575,7 @@ static void *diskstats_next(struct seq_file *part, void *v, loff_t *pos) { struct list_head *p = ((struct gendisk *)v)->kobj.entry.next; ++*pos; - return p==&block_subsys.kset.list ? NULL : + return p==&block_subsys.list ? NULL : list_entry(p, struct gendisk, kobj.entry); } diff --git a/block/ll_rw_blk.c b/block/ll_rw_blk.c index cf8752abd61a..5873861e1dbb 100644 --- a/block/ll_rw_blk.c +++ b/block/ll_rw_blk.c @@ -1221,7 +1221,7 @@ void blk_recount_segments(request_queue_t *q, struct bio *bio) * considered part of another segment, since that might * change with the bounce page. */ - high = page_to_pfn(bv->bv_page) >= q->bounce_pfn; + high = page_to_pfn(bv->bv_page) > q->bounce_pfn; if (high || highprv) goto new_hw_segment; if (cluster) { @@ -3660,8 +3660,8 @@ int __init blk_dev_init(void) open_softirq(BLOCK_SOFTIRQ, blk_done_softirq, NULL); register_hotcpu_notifier(&blk_cpu_notifier); - blk_max_low_pfn = max_low_pfn; - blk_max_pfn = max_pfn; + blk_max_low_pfn = max_low_pfn - 1; + blk_max_pfn = max_pfn - 1; return 0; } @@ -3743,6 +3743,7 @@ static struct io_context *current_io_context(gfp_t gfp_flags, int node) ret->nr_batch_requests = 0; /* because this is 0 */ ret->aic = NULL; ret->cic_root.rb_node = NULL; + ret->ioc_data = NULL; /* make sure set_task_ioprio() sees the settings above */ smp_wmb(); tsk->io_context = ret; |