* 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>
+ * Copyright (C) 2003 Jens Axboe <axboe@kernel.dk>
*/
#include <linux/module.h>
#include <linux/blkdev.h>
struct list_head idle_rr;
unsigned int busy_queues;
- /*
- * non-ordered list of empty cfqq's
- */
- struct list_head empty_list;
-
/*
* cfqq lookup hash
*/
struct hlist_node cfq_hash;
/* hash key */
unsigned int key;
- /* on either rr or empty list of cfqd */
+ /* member of the rr/busy/cur/idle cfqd list */
struct list_head cfq_list;
/* sorted list of pending requests */
struct rb_root sort_list;
int queued[2];
/* currently allocated requests */
int allocated[2];
+ /* pending metadata requests */
+ int meta_pending;
/* fifo list of requests in sort_list */
struct list_head fifo;
unsigned long slice_start;
unsigned long slice_end;
unsigned long slice_left;
- unsigned long service_last;
/* number of requests that are on the dispatch list */
int on_dispatch[2];
CFQ_CFQQ_FLAG_fifo_expire,
CFQ_CFQQ_FLAG_idle_window,
CFQ_CFQQ_FLAG_prio_changed,
+ CFQ_CFQQ_FLAG_queue_new,
};
#define CFQ_CFQQ_FNS(name) \
CFQ_CFQQ_FNS(fifo_expire);
CFQ_CFQQ_FNS(idle_window);
CFQ_CFQQ_FNS(prio_changed);
+CFQ_CFQQ_FNS(queue_new);
#undef CFQ_CFQQ_FNS
static struct cfq_queue *cfq_find_cfq_hash(struct cfq_data *, unsigned int, unsigned short);
return rq1;
else if (rq_is_sync(rq2) && !rq_is_sync(rq1))
return rq2;
+ if (rq_is_meta(rq1) && !rq_is_meta(rq2))
+ return rq1;
+ else if (rq_is_meta(rq2) && !rq_is_meta(rq1))
+ return rq2;
s1 = rq1->sector;
s2 = rq2->sector;
static void cfq_resort_rr_list(struct cfq_queue *cfqq, int preempted)
{
struct cfq_data *cfqd = cfqq->cfqd;
- struct list_head *list, *entry;
+ struct list_head *list;
BUG_ON(!cfq_cfqq_on_rr(cfqq));
}
/*
- * if queue was preempted, just add to front to be fair. busy_rr
- * isn't sorted, but insert at the back for fairness.
+ * If this queue was preempted or is new (never been serviced), let
+ * it be added first for fairness but beind other new queues.
+ * Otherwise, just add to the back of the list.
*/
- if (preempted || list == &cfqd->busy_rr) {
- if (preempted)
- list = list->prev;
+ if (preempted || cfq_cfqq_queue_new(cfqq)) {
+ struct list_head *n = list;
+ struct cfq_queue *__cfqq;
- list_add_tail(&cfqq->cfq_list, list);
- return;
- }
+ while (n->next != list) {
+ __cfqq = list_entry_cfqq(n->next);
+ if (!cfq_cfqq_queue_new(__cfqq))
+ break;
- /*
- * sort by when queue was last serviced
- */
- entry = list;
- while ((entry = entry->prev) != list) {
- struct cfq_queue *__cfqq = list_entry_cfqq(entry);
+ n = n->next;
+ }
- if (!__cfqq->service_last)
- break;
- if (time_before(__cfqq->service_last, cfqq->service_last))
- break;
+ list = n;
}
- list_add(&cfqq->cfq_list, entry);
+ list_add_tail(&cfqq->cfq_list, list);
}
/*
{
BUG_ON(!cfq_cfqq_on_rr(cfqq));
cfq_clear_cfqq_on_rr(cfqq);
- list_move(&cfqq->cfq_list, &cfqd->empty_list);
+ list_del_init(&cfqq->cfq_list);
BUG_ON(!cfqd->busy_queues);
cfqd->busy_queues--;
list_del_init(&rq->queuelist);
cfq_del_rq_rb(rq);
+
+ if (rq_is_meta(rq)) {
+ WARN_ON(!cfqq->meta_pending);
+ cfqq->meta_pending--;
+ }
}
static int
if (cfq_cfqq_wait_request(cfqq))
del_timer(&cfqd->idle_slice_timer);
- if (!preempted && !cfq_cfqq_dispatched(cfqq)) {
- cfqq->service_last = now;
+ if (!preempted && !cfq_cfqq_dispatched(cfqq))
cfq_schedule_dispatch(cfqd);
- }
cfq_clear_cfqq_must_dispatch(cfqq);
cfq_clear_cfqq_wait_request(cfqq);
+ cfq_clear_cfqq_queue_new(cfqq);
/*
* store what was left of this slice, if the queue idled out
static struct cfq_io_context *
cfq_alloc_io_context(struct cfq_data *cfqd, gfp_t gfp_mask)
{
- struct cfq_io_context *cic = kmem_cache_alloc(cfq_ioc_pool, gfp_mask);
+ struct cfq_io_context *cic;
+ cic = kmem_cache_alloc_node(cfq_ioc_pool, gfp_mask, cfqd->queue->node);
if (cic) {
memset(cic, 0, sizeof(*cic));
cic->last_end_request = jiffies;
* free memory.
*/
spin_unlock_irq(cfqd->queue->queue_lock);
- new_cfqq = kmem_cache_alloc(cfq_pool, gfp_mask|__GFP_NOFAIL);
+ new_cfqq = kmem_cache_alloc_node(cfq_pool, gfp_mask|__GFP_NOFAIL, cfqd->queue->node);
spin_lock_irq(cfqd->queue->queue_lock);
goto retry;
} else {
- cfqq = kmem_cache_alloc(cfq_pool, gfp_mask);
+ cfqq = kmem_cache_alloc_node(cfq_pool, gfp_mask, cfqd->queue->node);
if (!cfqq)
goto out;
}
hlist_add_head(&cfqq->cfq_hash, &cfqd->cfq_hash[hashval]);
atomic_set(&cfqq->ref, 0);
cfqq->cfqd = cfqd;
- cfqq->service_last = 0;
/*
* set ->slice_left to allow preemption for a new process
*/
cfqq->slice_left = 2 * cfqd->cfq_slice_idle;
cfq_mark_cfqq_idle_window(cfqq);
cfq_mark_cfqq_prio_changed(cfqq);
+ cfq_mark_cfqq_queue_new(cfqq);
cfq_init_prio_data(cfqq);
}
might_sleep_if(gfp_mask & __GFP_WAIT);
- ioc = get_io_context(gfp_mask);
+ ioc = get_io_context(gfp_mask, cfqd->queue->node);
if (!ioc)
return NULL;
*/
if (new_cfqq->slice_left < cfqd->cfq_slice_idle)
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.
+ */
+ if (rq_is_meta(rq) && !cfqq->meta_pending)
+ return 1;
return 0;
}
*/
static void cfq_preempt_queue(struct cfq_data *cfqd, struct cfq_queue *cfqq)
{
- struct cfq_queue *__cfqq, *next;
-
- list_for_each_entry_safe(__cfqq, next, &cfqd->cur_rr, cfq_list)
- cfq_resort_rr_list(__cfqq, 1);
+ cfq_slice_expired(cfqd, 1);
if (!cfqq->slice_left)
cfqq->slice_left = cfq_prio_to_slice(cfqd, cfqq) / 2;
- cfqq->slice_end = cfqq->slice_left + jiffies;
- cfq_slice_expired(cfqd, 1);
- __cfq_set_active_queue(cfqd, cfqq);
-}
-
-/*
- * should really be a ll_rw_blk.c helper
- */
-static void cfq_start_queueing(struct cfq_data *cfqd, struct cfq_queue *cfqq)
-{
- request_queue_t *q = cfqd->queue;
+ /*
+ * Put the new queue at the front of the of the current list,
+ * so we know that it will be selected next.
+ */
+ BUG_ON(!cfq_cfqq_on_rr(cfqq));
+ list_move(&cfqq->cfq_list, &cfqd->cur_rr);
- if (!blk_queue_plugged(q))
- q->request_fn(q);
- else
- __generic_unplug_device(q);
+ cfqq->slice_end = cfqq->slice_left + jiffies;
}
/*
{
struct cfq_io_context *cic = RQ_CIC(rq);
+ if (rq_is_meta(rq))
+ cfqq->meta_pending++;
+
/*
* check if this request is a better next-serve candidate)) {
*/
if (cic == cfqd->active_cic &&
del_timer(&cfqd->idle_slice_timer)) {
cfq_slice_expired(cfqd, 0);
- cfq_start_queueing(cfqd, cfqq);
+ blk_start_queueing(cfqd->queue);
}
return;
}
if (cfq_cfqq_wait_request(cfqq)) {
cfq_mark_cfqq_must_dispatch(cfqq);
del_timer(&cfqd->idle_slice_timer);
- cfq_start_queueing(cfqd, cfqq);
+ blk_start_queueing(cfqd->queue);
}
} else if (cfq_should_preempt(cfqd, cfqq, rq)) {
/*
*/
cfq_preempt_queue(cfqd, cfqq);
cfq_mark_cfqq_must_dispatch(cfqq);
- cfq_start_queueing(cfqd, cfqq);
+ blk_start_queueing(cfqd->queue);
}
}
if (!cfq_class_idle(cfqq))
cfqd->last_end_request = now;
- if (!cfq_cfqq_dispatched(cfqq)) {
- if (cfq_cfqq_on_rr(cfqq)) {
- cfqq->service_last = now;
- cfq_resort_rr_list(cfqq, 0);
- }
- }
+ if (!cfq_cfqq_dispatched(cfqq) && cfq_cfqq_on_rr(cfqq))
+ cfq_resort_rr_list(cfqq, 0);
if (sync)
RQ_CIC(rq)->last_end_request = now;
unsigned long flags;
spin_lock_irqsave(q->queue_lock, flags);
- blk_remove_plug(q);
- q->request_fn(q);
+ blk_start_queueing(q);
spin_unlock_irqrestore(q->queue_lock, flags);
}
struct cfq_data *cfqd;
int i;
- cfqd = kmalloc(sizeof(*cfqd), GFP_KERNEL);
+ cfqd = kmalloc_node(sizeof(*cfqd), GFP_KERNEL, q->node);
if (!cfqd)
return NULL;
INIT_LIST_HEAD(&cfqd->busy_rr);
INIT_LIST_HEAD(&cfqd->cur_rr);
INIT_LIST_HEAD(&cfqd->idle_rr);
- INIT_LIST_HEAD(&cfqd->empty_list);
INIT_LIST_HEAD(&cfqd->cic_list);
- cfqd->cfq_hash = kmalloc(sizeof(struct hlist_head) * CFQ_QHASH_ENTRIES, GFP_KERNEL);
+ cfqd->cfq_hash = kmalloc_node(sizeof(struct hlist_head) * CFQ_QHASH_ENTRIES, GFP_KERNEL, q->node);
if (!cfqd->cfq_hash)
goto out_free;