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-rw-r--r--drivers/block/as-iosched.c327
-rw-r--r--drivers/block/cfq-iosched.c372
-rw-r--r--drivers/block/deadline-iosched.c125
-rw-r--r--drivers/block/elevator.c345
-rw-r--r--drivers/block/ll_rw_blk.c193
-rw-r--r--drivers/block/loop.c2
-rw-r--r--drivers/block/noop-iosched.c48
-rw-r--r--drivers/block/rd.c2
-rw-r--r--drivers/block/sx8.c51
9 files changed, 500 insertions, 965 deletions
diff --git a/drivers/block/as-iosched.c b/drivers/block/as-iosched.c
index 95c0a3690b0..4081c36c8c1 100644
--- a/drivers/block/as-iosched.c
+++ b/drivers/block/as-iosched.c
@@ -98,7 +98,6 @@ struct as_data {
struct as_rq *next_arq[2]; /* next in sort order */
sector_t last_sector[2]; /* last REQ_SYNC & REQ_ASYNC sectors */
- struct list_head *dispatch; /* driver dispatch queue */
struct list_head *hash; /* request hash */
unsigned long exit_prob; /* probability a task will exit while
@@ -239,6 +238,25 @@ static struct io_context *as_get_io_context(void)
return ioc;
}
+static void as_put_io_context(struct as_rq *arq)
+{
+ struct as_io_context *aic;
+
+ if (unlikely(!arq->io_context))
+ return;
+
+ aic = arq->io_context->aic;
+
+ if (arq->is_sync == REQ_SYNC && aic) {
+ spin_lock(&aic->lock);
+ set_bit(AS_TASK_IORUNNING, &aic->state);
+ aic->last_end_request = jiffies;
+ spin_unlock(&aic->lock);
+ }
+
+ put_io_context(arq->io_context);
+}
+
/*
* the back merge hash support functions
*/
@@ -261,14 +279,6 @@ static inline void as_del_arq_hash(struct as_rq *arq)
__as_del_arq_hash(arq);
}
-static void as_remove_merge_hints(request_queue_t *q, struct as_rq *arq)
-{
- as_del_arq_hash(arq);
-
- if (q->last_merge == arq->request)
- q->last_merge = NULL;
-}
-
static void as_add_arq_hash(struct as_data *ad, struct as_rq *arq)
{
struct request *rq = arq->request;
@@ -312,7 +322,7 @@ static struct request *as_find_arq_hash(struct as_data *ad, sector_t offset)
BUG_ON(!arq->on_hash);
if (!rq_mergeable(__rq)) {
- as_remove_merge_hints(ad->q, arq);
+ as_del_arq_hash(arq);
continue;
}
@@ -950,23 +960,12 @@ static void as_completed_request(request_queue_t *q, struct request *rq)
WARN_ON(!list_empty(&rq->queuelist));
- if (arq->state == AS_RQ_PRESCHED) {
- WARN_ON(arq->io_context);
- goto out;
- }
-
- if (arq->state == AS_RQ_MERGED)
- goto out_ioc;
-
if (arq->state != AS_RQ_REMOVED) {
printk("arq->state %d\n", arq->state);
WARN_ON(1);
goto out;
}
- if (!blk_fs_request(rq))
- goto out;
-
if (ad->changed_batch && ad->nr_dispatched == 1) {
kblockd_schedule_work(&ad->antic_work);
ad->changed_batch = 0;
@@ -1001,21 +1000,7 @@ static void as_completed_request(request_queue_t *q, struct request *rq)
}
}
-out_ioc:
- if (!arq->io_context)
- goto out;
-
- if (arq->is_sync == REQ_SYNC) {
- struct as_io_context *aic = arq->io_context->aic;
- if (aic) {
- spin_lock(&aic->lock);
- set_bit(AS_TASK_IORUNNING, &aic->state);
- aic->last_end_request = jiffies;
- spin_unlock(&aic->lock);
- }
- }
-
- put_io_context(arq->io_context);
+ as_put_io_context(arq);
out:
arq->state = AS_RQ_POSTSCHED;
}
@@ -1047,73 +1032,11 @@ static void as_remove_queued_request(request_queue_t *q, struct request *rq)
ad->next_arq[data_dir] = as_find_next_arq(ad, arq);
list_del_init(&arq->fifo);
- as_remove_merge_hints(q, arq);
+ as_del_arq_hash(arq);
as_del_arq_rb(ad, arq);
}
/*
- * as_remove_dispatched_request is called to remove a request which has gone
- * to the dispatch list.
- */
-static void as_remove_dispatched_request(request_queue_t *q, struct request *rq)
-{
- struct as_rq *arq = RQ_DATA(rq);
- struct as_io_context *aic;
-
- if (!arq) {
- WARN_ON(1);
- return;
- }
-
- WARN_ON(arq->state != AS_RQ_DISPATCHED);
- WARN_ON(ON_RB(&arq->rb_node));
- if (arq->io_context && arq->io_context->aic) {
- aic = arq->io_context->aic;
- if (aic) {
- WARN_ON(!atomic_read(&aic->nr_dispatched));
- atomic_dec(&aic->nr_dispatched);
- }
- }
-}
-
-/*
- * as_remove_request is called when a driver has finished with a request.
- * This should be only called for dispatched requests, but for some reason
- * a POWER4 box running hwscan it does not.
- */
-static void as_remove_request(request_queue_t *q, struct request *rq)
-{
- struct as_rq *arq = RQ_DATA(rq);
-
- if (unlikely(arq->state == AS_RQ_NEW))
- goto out;
-
- if (ON_RB(&arq->rb_node)) {
- if (arq->state != AS_RQ_QUEUED) {
- printk("arq->state %d\n", arq->state);
- WARN_ON(1);
- goto out;
- }
- /*
- * We'll lose the aliased request(s) here. I don't think this
- * will ever happen, but if it does, hopefully someone will
- * report it.
- */
- WARN_ON(!list_empty(&rq->queuelist));
- as_remove_queued_request(q, rq);
- } else {
- if (arq->state != AS_RQ_DISPATCHED) {
- printk("arq->state %d\n", arq->state);
- WARN_ON(1);
- goto out;
- }
- as_remove_dispatched_request(q, rq);
- }
-out:
- arq->state = AS_RQ_REMOVED;
-}
-
-/*
* as_fifo_expired returns 0 if there are no expired reads on the fifo,
* 1 otherwise. It is ratelimited so that we only perform the check once per
* `fifo_expire' interval. Otherwise a large number of expired requests
@@ -1165,7 +1088,6 @@ static inline int as_batch_expired(struct as_data *ad)
static void as_move_to_dispatch(struct as_data *ad, struct as_rq *arq)
{
struct request *rq = arq->request;
- struct list_head *insert;
const int data_dir = arq->is_sync;
BUG_ON(!ON_RB(&arq->rb_node));
@@ -1198,13 +1120,13 @@ static void as_move_to_dispatch(struct as_data *ad, struct as_rq *arq)
/*
* take it off the sort and fifo list, add to dispatch queue
*/
- insert = ad->dispatch->prev;
-
while (!list_empty(&rq->queuelist)) {
struct request *__rq = list_entry_rq(rq->queuelist.next);
struct as_rq *__arq = RQ_DATA(__rq);
- list_move_tail(&__rq->queuelist, ad->dispatch);
+ list_del(&__rq->queuelist);
+
+ elv_dispatch_add_tail(ad->q, __rq);
if (__arq->io_context && __arq->io_context->aic)
atomic_inc(&__arq->io_context->aic->nr_dispatched);
@@ -1218,7 +1140,8 @@ static void as_move_to_dispatch(struct as_data *ad, struct as_rq *arq)
as_remove_queued_request(ad->q, rq);
WARN_ON(arq->state != AS_RQ_QUEUED);
- list_add(&rq->queuelist, insert);
+ elv_dispatch_sort(ad->q, rq);
+
arq->state = AS_RQ_DISPATCHED;
if (arq->io_context && arq->io_context->aic)
atomic_inc(&arq->io_context->aic->nr_dispatched);
@@ -1230,12 +1153,42 @@ static void as_move_to_dispatch(struct as_data *ad, struct as_rq *arq)
* read/write expire, batch expire, etc, and moves it to the dispatch
* queue. Returns 1 if a request was found, 0 otherwise.
*/
-static int as_dispatch_request(struct as_data *ad)
+static int as_dispatch_request(request_queue_t *q, int force)
{
+ struct as_data *ad = q->elevator->elevator_data;
struct as_rq *arq;
const int reads = !list_empty(&ad->fifo_list[REQ_SYNC]);
const int writes = !list_empty(&ad->fifo_list[REQ_ASYNC]);
+ if (unlikely(force)) {
+ /*
+ * Forced dispatch, accounting is useless. Reset
+ * accounting states and dump fifo_lists. Note that
+ * batch_data_dir is reset to REQ_SYNC to avoid
+ * screwing write batch accounting as write batch
+ * accounting occurs on W->R transition.
+ */
+ int dispatched = 0;
+
+ ad->batch_data_dir = REQ_SYNC;
+ ad->changed_batch = 0;
+ ad->new_batch = 0;
+
+ while (ad->next_arq[REQ_SYNC]) {
+ as_move_to_dispatch(ad, ad->next_arq[REQ_SYNC]);
+ dispatched++;
+ }
+ ad->last_check_fifo[REQ_SYNC] = jiffies;
+
+ while (ad->next_arq[REQ_ASYNC]) {
+ as_move_to_dispatch(ad, ad->next_arq[REQ_ASYNC]);
+ dispatched++;
+ }
+ ad->last_check_fifo[REQ_ASYNC] = jiffies;
+
+ return dispatched;
+ }
+
/* Signal that the write batch was uncontended, so we can't time it */
if (ad->batch_data_dir == REQ_ASYNC && !reads) {
if (ad->current_write_count == 0 || !writes)
@@ -1359,20 +1312,6 @@ fifo_expired:
return 1;
}
-static struct request *as_next_request(request_queue_t *q)
-{
- struct as_data *ad = q->elevator->elevator_data;
- struct request *rq = NULL;
-
- /*
- * if there are still requests on the dispatch queue, grab the first
- */
- if (!list_empty(ad->dispatch) || as_dispatch_request(ad))
- rq = list_entry_rq(ad->dispatch->next);
-
- return rq;
-}
-
/*
* Add arq to a list behind alias
*/
@@ -1404,17 +1343,25 @@ as_add_aliased_request(struct as_data *ad, struct as_rq *arq, struct as_rq *alia
/*
* Don't want to have to handle merges.
*/
- as_remove_merge_hints(ad->q, arq);
+ as_del_arq_hash(arq);
}
/*
* add arq to rbtree and fifo
*/
-static void as_add_request(struct as_data *ad, struct as_rq *arq)
+static void as_add_request(request_queue_t *q, struct request *rq)
{
+ struct as_data *ad = q->elevator->elevator_data;
+ struct as_rq *arq = RQ_DATA(rq);
struct as_rq *alias;
int data_dir;
+ if (arq->state != AS_RQ_PRESCHED) {
+ printk("arq->state: %d\n", arq->state);
+ WARN_ON(1);
+ }
+ arq->state = AS_RQ_NEW;
+
if (rq_data_dir(arq->request) == READ
|| current->flags&PF_SYNCWRITE)
arq->is_sync = 1;
@@ -1437,12 +1384,8 @@ static void as_add_request(struct as_data *ad, struct as_rq *arq)
arq->expires = jiffies + ad->fifo_expire[data_dir];
list_add_tail(&arq->fifo, &ad->fifo_list[data_dir]);
- if (rq_mergeable(arq->request)) {
+ if (rq_mergeable(arq->request))
as_add_arq_hash(ad, arq);
-
- if (!ad->q->last_merge)
- ad->q->last_merge = arq->request;
- }
as_update_arq(ad, arq); /* keep state machine up to date */
} else {
@@ -1463,96 +1406,24 @@ static void as_add_request(struct as_data *ad, struct as_rq *arq)
arq->state = AS_RQ_QUEUED;
}
-static void as_deactivate_request(request_queue_t *q, struct request *rq)
+static void as_activate_request(request_queue_t *q, struct request *rq)
{
- struct as_data *ad = q->elevator->elevator_data;
struct as_rq *arq = RQ_DATA(rq);
- if (arq) {
- if (arq->state == AS_RQ_REMOVED) {
- arq->state = AS_RQ_DISPATCHED;
- if (arq->io_context && arq->io_context->aic)
- atomic_inc(&arq->io_context->aic->nr_dispatched);
- }
- } else
- WARN_ON(blk_fs_request(rq)
- && (!(rq->flags & (REQ_HARDBARRIER|REQ_SOFTBARRIER))) );
-
- /* Stop anticipating - let this request get through */
- as_antic_stop(ad);
-}
-
-/*
- * requeue the request. The request has not been completed, nor is it a
- * new request, so don't touch accounting.
- */
-static void as_requeue_request(request_queue_t *q, struct request *rq)
-{
- as_deactivate_request(q, rq);
- list_add(&rq->queuelist, &q->queue_head);
-}
-
-/*
- * Account a request that is inserted directly onto the dispatch queue.
- * arq->io_context->aic->nr_dispatched should not need to be incremented
- * because only new requests should come through here: requeues go through
- * our explicit requeue handler.
- */
-static void as_account_queued_request(struct as_data *ad, struct request *rq)
-{
- if (blk_fs_request(rq)) {
- struct as_rq *arq = RQ_DATA(rq);
- arq->state = AS_RQ_DISPATCHED;
- ad->nr_dispatched++;
- }
+ WARN_ON(arq->state != AS_RQ_DISPATCHED);
+ arq->state = AS_RQ_REMOVED;
+ if (arq->io_context && arq->io_context->aic)
+ atomic_dec(&arq->io_context->aic->nr_dispatched);
}
-static void
-as_insert_request(request_queue_t *q, struct request *rq, int where)
+static void as_deactivate_request(request_queue_t *q, struct request *rq)
{
- struct as_data *ad = q->elevator->elevator_data;
struct as_rq *arq = RQ_DATA(rq);
- if (arq) {
- if (arq->state != AS_RQ_PRESCHED) {
- printk("arq->state: %d\n", arq->state);
- WARN_ON(1);
- }
- arq->state = AS_RQ_NEW;
- }
-
- /* barriers must flush the reorder queue */
- if (unlikely(rq->flags & (REQ_SOFTBARRIER | REQ_HARDBARRIER)
- && where == ELEVATOR_INSERT_SORT)) {
- WARN_ON(1);
- where = ELEVATOR_INSERT_BACK;
- }
-
- switch (where) {
- case ELEVATOR_INSERT_BACK:
- while (ad->next_arq[REQ_SYNC])
- as_move_to_dispatch(ad, ad->next_arq[REQ_SYNC]);
-
- while (ad->next_arq[REQ_ASYNC])
- as_move_to_dispatch(ad, ad->next_arq[REQ_ASYNC]);
-
- list_add_tail(&rq->queuelist, ad->dispatch);
- as_account_queued_request(ad, rq);
- as_antic_stop(ad);
- break;
- case ELEVATOR_INSERT_FRONT:
- list_add(&rq->queuelist, ad->dispatch);
- as_account_queued_request(ad, rq);
- as_antic_stop(ad);
- break;
- case ELEVATOR_INSERT_SORT:
- BUG_ON(!blk_fs_request(rq));
- as_add_request(ad, arq);
- break;
- default:
- BUG();
- return;
- }
+ WARN_ON(arq->state != AS_RQ_REMOVED);
+ arq->state = AS_RQ_DISPATCHED;
+ if (arq->io_context && arq->io_context->aic)
+ atomic_inc(&arq->io_context->aic->nr_dispatched);
}
/*
@@ -1565,12 +1436,8 @@ static int as_queue_empty(request_queue_t *q)
{
struct as_data *ad = q->elevator->elevator_data;
- if (!list_empty(&ad->fifo_list[REQ_ASYNC])
- || !list_empty(&ad->fifo_list[REQ_SYNC])
- || !list_empty(ad->dispatch))
- return 0;
-
- return 1;
+ return list_empty(&ad->fifo_list[REQ_ASYNC])
+ && list_empty(&ad->fifo_list[REQ_SYNC]);
}
static struct request *
@@ -1608,15 +1475,6 @@ as_merge(request_queue_t *q, struct request **req, struct bio *bio)
int ret;
/*
- * try last_merge to avoid going to hash
- */
- ret = elv_try_last_merge(q, bio);
- if (ret != ELEVATOR_NO_MERGE) {
- __rq = q->last_merge;
- goto out_insert;
- }
-
- /*
* see if the merge hash can satisfy a back merge
*/
__rq = as_find_arq_hash(ad, bio->bi_sector);
@@ -1644,9 +1502,6 @@ as_merge(request_queue_t *q, struct request **req, struct bio *bio)
return ELEVATOR_NO_MERGE;
out:
- if (rq_mergeable(__rq))
- q->last_merge = __rq;
-out_insert:
if (ret) {
if (rq_mergeable(__rq))
as_hot_arq_hash(ad, RQ_DATA(__rq));
@@ -1693,9 +1548,6 @@ static void as_merged_request(request_queue_t *q, struct request *req)
* behind the disk head. We currently don't bother adjusting.
*/
}
-
- if (arq->on_hash)
- q->last_merge = req;
}
static void
@@ -1763,6 +1615,7 @@ as_merged_requests(request_queue_t *q, struct request *req,
* kill knowledge of next, this one is a goner
*/
as_remove_queued_request(q, next);
+ as_put_io_context(anext);
anext->state = AS_RQ_MERGED;
}
@@ -1782,7 +1635,7 @@ static void as_work_handler(void *data)
unsigned long flags;
spin_lock_irqsave(q->queue_lock, flags);
- if (as_next_request(q))
+ if (!as_queue_empty(q))
q->request_fn(q);
spin_unlock_irqrestore(q->queue_lock, flags);
}
@@ -1797,7 +1650,9 @@ static void as_put_request(request_queue_t *q, struct request *rq)
return;
}
- if (arq->state != AS_RQ_POSTSCHED && arq->state != AS_RQ_PRESCHED) {
+ if (unlikely(arq->state != AS_RQ_POSTSCHED &&
+ arq->state != AS_RQ_PRESCHED &&
+ arq->state != AS_RQ_MERGED)) {
printk("arq->state %d\n", arq->state);
WARN_ON(1);
}
@@ -1807,7 +1662,7 @@ static void as_put_request(request_queue_t *q, struct request *rq)
}
static int as_set_request(request_queue_t *q, struct request *rq,
- struct bio *bio, int gfp_mask)
+ struct bio *bio, gfp_t gfp_mask)
{
struct as_data *ad = q->elevator->elevator_data;
struct as_rq *arq = mempool_alloc(ad->arq_pool, gfp_mask);
@@ -1907,7 +1762,6 @@ static int as_init_queue(request_queue_t *q, elevator_t *e)
INIT_LIST_HEAD(&ad->fifo_list[REQ_ASYNC]);
ad->sort_list[REQ_SYNC] = RB_ROOT;
ad->sort_list[REQ_ASYNC] = RB_ROOT;
- ad->dispatch = &q->queue_head;
ad->fifo_expire[REQ_SYNC] = default_read_expire;
ad->fifo_expire[REQ_ASYNC] = default_write_expire;
ad->antic_expire = default_antic_expire;
@@ -2072,10 +1926,9 @@ static struct elevator_type iosched_as = {
.elevator_merge_fn = as_merge,
.elevator_merged_fn = as_merged_request,
.elevator_merge_req_fn = as_merged_requests,
- .elevator_next_req_fn = as_next_request,
- .elevator_add_req_fn = as_insert_request,
- .elevator_remove_req_fn = as_remove_request,
- .elevator_requeue_req_fn = as_requeue_request,
+ .elevator_dispatch_fn = as_dispatch_request,
+ .elevator_add_req_fn = as_add_request,
+ .elevator_activate_req_fn = as_activate_request,
.elevator_deactivate_req_fn = as_deactivate_request,
.elevator_queue_empty_fn = as_queue_empty,
.elevator_completed_req_fn = as_completed_request,
diff --git a/drivers/block/cfq-iosched.c b/drivers/block/cfq-iosched.c
index cd056e7e64e..94690e4d41e 100644
--- a/drivers/block/cfq-iosched.c
+++ b/drivers/block/cfq-iosched.c
@@ -84,7 +84,6 @@ static int cfq_max_depth = 2;
(node)->rb_left = NULL; \
} while (0)
#define RB_CLEAR_ROOT(root) ((root)->rb_node = NULL)
-#define ON_RB(node) ((node)->rb_color != RB_NONE)
#define rb_entry_crq(node) rb_entry((node), struct cfq_rq, rb_node)
#define rq_rb_key(rq) (rq)->sector
@@ -271,10 +270,7 @@ CFQ_CFQQ_FNS(expired);
#undef CFQ_CFQQ_FNS
enum cfq_rq_state_flags {
- CFQ_CRQ_FLAG_in_flight = 0,
- CFQ_CRQ_FLAG_in_driver,
- CFQ_CRQ_FLAG_is_sync,
- CFQ_CRQ_FLAG_requeued,
+ CFQ_CRQ_FLAG_is_sync = 0,
};
#define CFQ_CRQ_FNS(name) \
@@ -291,14 +287,11 @@ static inline int cfq_crq_##name(const struct cfq_rq *crq) \
return (crq->crq_flags & (1 << CFQ_CRQ_FLAG_##name)) != 0; \
}
-CFQ_CRQ_FNS(in_flight);
-CFQ_CRQ_FNS(in_driver);
CFQ_CRQ_FNS(is_sync);
-CFQ_CRQ_FNS(requeued);
#undef CFQ_CRQ_FNS
static struct cfq_queue *cfq_find_cfq_hash(struct cfq_data *, unsigned int, unsigned short);
-static void cfq_dispatch_sort(request_queue_t *, struct cfq_rq *);
+static void cfq_dispatch_insert(request_queue_t *, struct cfq_rq *);
static void cfq_put_cfqd(struct cfq_data *cfqd);
#define process_sync(tsk) ((tsk)->flags & PF_SYNCWRITE)
@@ -311,14 +304,6 @@ static inline void cfq_del_crq_hash(struct cfq_rq *crq)
hlist_del_init(&crq->hash);
}
-static void cfq_remove_merge_hints(request_queue_t *q, struct cfq_rq *crq)
-{
- cfq_del_crq_hash(crq);
-
- if (q->last_merge == crq->request)
- q->last_merge = NULL;
-}
-
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));
@@ -347,18 +332,13 @@ static struct request *cfq_find_rq_hash(struct cfq_data *cfqd, sector_t offset)
return NULL;
}
-static inline int cfq_pending_requests(struct cfq_data *cfqd)
-{
- return !list_empty(&cfqd->queue->queue_head) || cfqd->busy_queues;
-}
-
/*
* 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)
{
- if (!cfqd->rq_in_driver && cfq_pending_requests(cfqd))
+ if (!cfqd->rq_in_driver && cfqd->busy_queues)
kblockd_schedule_work(&cfqd->unplug_work);
}
@@ -366,7 +346,7 @@ static int cfq_queue_empty(request_queue_t *q)
{
struct cfq_data *cfqd = q->elevator->elevator_data;
- return !cfq_pending_requests(cfqd);
+ return !cfqd->busy_queues;
}
/*
@@ -386,11 +366,6 @@ cfq_choose_req(struct cfq_data *cfqd, struct cfq_rq *crq1, struct cfq_rq *crq2)
if (crq2 == NULL)
return crq1;
- if (cfq_crq_requeued(crq1) && !cfq_crq_requeued(crq2))
- return crq1;
- else if (cfq_crq_requeued(crq2) && !cfq_crq_requeued(crq1))
- return crq2;
-
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))
@@ -461,10 +436,7 @@ cfq_find_next_crq(struct cfq_data *cfqd, struct cfq_queue *cfqq,
struct cfq_rq *crq_next = NULL, *crq_prev = NULL;
struct rb_node *rbnext, *rbprev;
- rbnext = NULL;
- if (ON_RB(&last->rb_node))
- rbnext = rb_next(&last->rb_node);
- if (!rbnext) {
+ if (!(rbnext = rb_next(&last->rb_node))) {
rbnext = rb_first(&cfqq->sort_list);
if (rbnext == &last->rb_node)
rbnext = NULL;
@@ -545,13 +517,13 @@ static void cfq_resort_rr_list(struct cfq_queue *cfqq, int preempted)
* the pending list according to last request service
*/
static inline void
-cfq_add_cfqq_rr(struct cfq_data *cfqd, struct cfq_queue *cfqq, int requeue)
+cfq_add_cfqq_rr(struct cfq_data *cfqd, struct cfq_queue *cfqq)
{
BUG_ON(cfq_cfqq_on_rr(cfqq));
cfq_mark_cfqq_on_rr(cfqq);
cfqd->busy_queues++;
- cfq_resort_rr_list(cfqq, requeue);
+ cfq_resort_rr_list(cfqq, 0);
}
static inline void
@@ -571,22 +543,19 @@ cfq_del_cfqq_rr(struct cfq_data *cfqd, struct cfq_queue *cfqq)
static inline void cfq_del_crq_rb(struct cfq_rq *crq)
{
struct cfq_queue *cfqq = crq->cfq_queue;
+ struct cfq_data *cfqd = cfqq->cfqd;
+ const int sync = cfq_crq_is_sync(crq);
- if (ON_RB(&crq->rb_node)) {
- struct cfq_data *cfqd = cfqq->cfqd;
- const int sync = cfq_crq_is_sync(crq);
+ BUG_ON(!cfqq->queued[sync]);
+ cfqq->queued[sync]--;
- BUG_ON(!cfqq->queued[sync]);
- cfqq->queued[sync]--;
+ cfq_update_next_crq(crq);
- cfq_update_next_crq(crq);
+ rb_erase(&crq->rb_node, &cfqq->sort_list);
+ RB_CLEAR_COLOR(&crq->rb_node);
- rb_erase(&crq->rb_node, &cfqq->sort_list);
- RB_CLEAR_COLOR(&crq->rb_node);
-
- if (cfq_cfqq_on_rr(cfqq) && RB_EMPTY(&cfqq->sort_list))
- cfq_del_cfqq_rr(cfqd, cfqq);
- }
+ if (cfq_cfqq_on_rr(cfqq) && RB_EMPTY(&cfqq->sort_list))
+ cfq_del_cfqq_rr(cfqd, cfqq);
}
static struct cfq_rq *
@@ -627,12 +596,12 @@ static void cfq_add_crq_rb(struct cfq_rq *crq)
* if that happens, put the alias on the dispatch list
*/
while ((__alias = __cfq_add_crq_rb(crq)) != NULL)
- cfq_dispatch_sort(cfqd->queue, __alias);
+ cfq_dispatch_insert(cfqd->queue, __alias);
rb_insert_color(&crq->rb_node, &cfqq->sort_list);
if (!cfq_cfqq_on_rr(cfqq))
- cfq_add_cfqq_rr(cfqd, cfqq, cfq_crq_requeued(crq));
+ cfq_add_cfqq_rr(cfqd, cfqq);
/*
* check if this request is a better next-serve candidate
@@ -643,10 +612,8 @@ static void cfq_add_crq_rb(struct cfq_rq *crq)
static inline void
cfq_reposition_crq_rb(struct cfq_queue *cfqq, struct cfq_rq *crq)
{
- if (ON_RB(&crq->rb_node)) {
- rb_erase(&crq->rb_node, &cfqq->sort_list);
- cfqq->queued[cfq_crq_is_sync(crq)]--;
- }
+ rb_erase(&crq->rb_node, &cfqq->sort_list);
+ cfqq->queued[cfq_crq_is_sync(crq)]--;
cfq_add_crq_rb(crq);
}
@@ -676,49 +643,28 @@ out:
return NULL;
}
-static void cfq_deactivate_request(request_queue_t *q, struct request *rq)
+static void cfq_activate_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;
-
- if (cfq_crq_in_driver(crq)) {
- cfq_clear_crq_in_driver(crq);
- WARN_ON(!cfqd->rq_in_driver);
- cfqd->rq_in_driver--;
- }
- if (cfq_crq_in_flight(crq)) {
- const int sync = cfq_crq_is_sync(crq);
- cfq_clear_crq_in_flight(crq);
- WARN_ON(!cfqq->on_dispatch[sync]);
- cfqq->on_dispatch[sync]--;
- }
- cfq_mark_crq_requeued(crq);
- }
+ cfqd->rq_in_driver++;
}
-/*
- * make sure the service time gets corrected on reissue of this request
- */
-static void cfq_requeue_request(request_queue_t *q, struct request *rq)
+static void cfq_deactivate_request(request_queue_t *q, struct request *rq)
{
- cfq_deactivate_request(q, rq);
- list_add(&rq->queuelist, &q->queue_head);
+ struct cfq_data *cfqd = q->elevator->elevator_data;
+
+ WARN_ON(!cfqd->rq_in_driver);
+ cfqd->rq_in_driver--;
}
-static void cfq_remove_request(request_queue_t *q, struct request *rq)
+static void cfq_remove_request(struct request *rq)
{
struct cfq_rq *crq = RQ_DATA(rq);
- if (crq) {
- list_del_init(&rq->queuelist);
- cfq_del_crq_rb(crq);
- cfq_remove_merge_hints(q, crq);
-
- }
+ list_del_init(&rq->queuelist);
+ cfq_del_crq_rb(crq);
+ cfq_del_crq_hash(crq);
}
static int
@@ -728,12 +674,6 @@ cfq_merge(request_queue_t *q, struct request **req, struct bio *bio)
struct request *__rq;
int ret;
- ret = elv_try_last_merge(q, bio);
- if (ret != ELEVATOR_NO_MERGE) {
- __rq = q->last_merge;
- goto out_insert;
- }
-
__rq = cfq_find_rq_hash(cfqd, bio->bi_sector);
if (__rq && elv_rq_merge_ok(__rq, bio)) {
ret = ELEVATOR_BACK_MERGE;
@@ -748,8 +688,6 @@ cfq_merge(request_queue_t *q, struct request **req, struct bio *bio)
return ELEVATOR_NO_MERGE;
out:
- q->last_merge = __rq;
-out_insert:
*req = __rq;
return ret;
}
@@ -762,14 +700,12 @@ static void cfq_merged_request(request_queue_t *q, struct request *req)
cfq_del_crq_hash(crq);
cfq_add_crq_hash(cfqd, crq);
- if (ON_RB(&crq->rb_node) && (rq_rb_key(req) != crq->rb_key)) {
+ if (rq_rb_key(req) != crq->rb_key) {
struct cfq_queue *cfqq = crq->cfq_queue;
cfq_update_next_crq(crq);
cfq_reposition_crq_rb(cfqq, crq);
}
-
- q->last_merge = req;
}
static void
@@ -785,7 +721,7 @@ cfq_merged_requests(request_queue_t *q, struct request *rq,
time_before(next->start_time, rq->start_time))
list_move(&rq->queuelist, &next->queuelist);
- cfq_remove_request(q, next);
+ cfq_remove_request(next);
}
static inline void
@@ -992,53 +928,15 @@ static int cfq_arm_slice_timer(struct cfq_data *cfqd, struct cfq_queue *cfqq)
return 1;
}
-/*
- * we dispatch cfqd->cfq_quantum requests in total from the rr_list queues,
- * this function sector sorts the selected request to minimize seeks. we start
- * at cfqd->last_sector, not 0.
- */
-static void cfq_dispatch_sort(request_queue_t *q, struct cfq_rq *crq)
+static void cfq_dispatch_insert(request_queue_t *q, struct cfq_rq *crq)
{
struct cfq_data *cfqd = q->elevator->elevator_data;
struct cfq_queue *cfqq = crq->cfq_queue;
- struct list_head *head = &q->queue_head, *entry = head;
- struct request *__rq;
- sector_t last;
-
- list_del(&crq->request->queuelist);
-
- last = cfqd->last_sector;
- list_for_each_entry_reverse(__rq, head, queuelist) {
- struct cfq_rq *__crq = RQ_DATA(__rq);
-
- if (blk_barrier_rq(__rq))
- break;
- if (!blk_fs_request(__rq))
- break;
- if (cfq_crq_requeued(__crq))
- break;
-
- if (__rq->sector <= crq->request->sector)
- break;
- if (__rq->sector > last && crq->request->sector < last) {
- last = crq->request->sector + crq->request->nr_sectors;
- break;
- }
- entry = &__rq->queuelist;
- }
-
- cfqd->last_sector = last;
cfqq->next_crq = cfq_find_next_crq(cfqd, cfqq, crq);
-
- cfq_del_crq_rb(crq);
- cfq_remove_merge_hints(q, crq);
-
- cfq_mark_crq_in_flight(crq);
- cfq_clear_crq_requeued(crq);
-
+ cfq_remove_request(crq->request);
cfqq->on_dispatch[cfq_crq_is_sync(crq)]++;
- list_add_tail(&crq->request->queuelist, entry);
+ elv_dispatch_sort(q, crq->request);
}
/*
@@ -1159,7 +1057,7 @@ __cfq_dispatch_requests(struct cfq_data *cfqd, struct cfq_queue *cfqq,
/*
* finally, insert request into driver dispatch list
*/
- cfq_dispatch_sort(cfqd->queue, crq);
+ cfq_dispatch_insert(cfqd->queue, crq);
cfqd->dispatch_slice++;
dispatched++;
@@ -1194,7 +1092,7 @@ __cfq_dispatch_requests(struct cfq_data *cfqd, struct cfq_queue *cfqq,
}
static int
-cfq_dispatch_requests(request_queue_t *q, int max_dispatch, int force)
+cfq_dispatch_requests(request_queue_t *q, int force)
{
struct cfq_data *cfqd = q->elevator->elevator_data;
struct cfq_queue *cfqq;
@@ -1204,12 +1102,25 @@ cfq_dispatch_requests(request_queue_t *q, int max_dispatch, int force)
cfqq = cfq_select_queue(cfqd, force);
if (cfqq) {
+ 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;
+
cfq_clear_cfqq_must_dispatch(cfqq);
cfq_clear_cfqq_wait_request(cfqq);
del_timer(&cfqd->idle_slice_timer);
- if (cfq_class_idle(cfqq))
- max_dispatch = 1;
+ if (!force) {
+ max_dispatch = cfqd->cfq_quantum;
+ if (cfq_class_idle(cfqq))
+ max_dispatch = 1;
+ } else
+ max_dispatch = INT_MAX;
return __cfq_dispatch_requests(cfqd, cfqq, max_dispatch);
}
@@ -1217,93 +1128,6 @@ cfq_dispatch_requests(request_queue_t *q, int max_dispatch, int force)
return 0;
}
-static inline void cfq_account_dispatch(struct cfq_rq *crq)
-{
- struct cfq_queue *cfqq = crq->cfq_queue;
- struct cfq_data *cfqd = cfqq->cfqd;
-
- if (unlikely(!blk_fs_request(crq->request)))
- return;
-
- /*
- * accounted bit is necessary since some drivers will call
- * elv_next_request() many times for the same request (eg ide)
- */
- if (cfq_crq_in_driver(crq))
- return;
-
- cfq_mark_crq_in_driver(crq);
- cfqd->rq_in_driver++;
-}
-
-static inline void
-cfq_account_completion(struct cfq_queue *cfqq, struct cfq_rq *crq)
-{
- struct cfq_data *cfqd = cfqq->cfqd;
- unsigned long now;
-
- if (!cfq_crq_in_driver(crq))
- return;
-
- now = jiffies;
-
- WARN_ON(!cfqd->rq_in_driver);
- cfqd->rq_in_driver--;
-
- 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_expired(cfqq)) {
- __cfq_slice_expired(cfqd, cfqq, 0);
- cfq_schedule_dispatch(cfqd);
- }
- }
-
- if (cfq_crq_is_sync(crq))
- crq->io_context->last_end_request = now;
-}
-
-static struct request *cfq_next_request(request_queue_t *q)
-{
- struct cfq_data *cfqd = q->elevator->elevator_data;
- struct request *rq;
-
- if (!list_empty(&q->queue_head)) {
- struct cfq_rq *crq;
-dispatch:
- rq = list_entry_rq(q->queue_head.next);
-
- crq = RQ_DATA(rq);
- if (crq) {
- struct cfq_queue *cfqq = crq->cfq_queue;
-
- /*
- * if idle window is disabled, allow queue buildup
- */
- if (!cfq_crq_in_driver(crq) &&
- !cfq_cfqq_idle_window(cfqq) &&
- !blk_barrier_rq(rq) &&
- cfqd->rq_in_driver >= cfqd->cfq_max_depth)
- return NULL;
-
- cfq_remove_merge_hints(q, crq);
- cfq_account_dispatch(crq);
- }
-
- return rq;
- }
-
- if (cfq_dispatch_requests(q, cfqd->cfq_quantum, 0))
- goto dispatch;
-
- return NULL;
-}
-
/*
* 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.
@@ -1422,7 +1246,7 @@ static void cfq_exit_io_context(struct cfq_io_context *cic)
}
static struct cfq_io_context *
-cfq_alloc_io_context(struct cfq_data *cfqd, int gfp_mask)
+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);
@@ -1517,7 +1341,7 @@ static int cfq_ioc_set_ioprio(struct io_context *ioc, unsigned int ioprio)
static struct cfq_queue *
cfq_get_queue(struct cfq_data *cfqd, unsigned int key, unsigned short ioprio,
- int gfp_mask)
+ gfp_t gfp_mask)
{
const int hashval = hash_long(key, CFQ_QHASH_SHIFT);
struct cfq_queue *cfqq, *new_cfqq = NULL;
@@ -1578,7 +1402,7 @@ out:
* cfqq, so we don't need to worry about it disappearing
*/
static struct cfq_io_context *
-cfq_get_io_context(struct cfq_data *cfqd, pid_t pid, int gfp_mask)
+cfq_get_io_context(struct cfq_data *cfqd, pid_t pid, gfp_t gfp_mask)
{
struct io_context *ioc = NULL;
struct cfq_io_context *cic;
@@ -1816,8 +1640,9 @@ cfq_crq_enqueued(struct cfq_data *cfqd, struct cfq_queue *cfqq,
}
}
-static void cfq_enqueue(struct cfq_data *cfqd, struct request *rq)
+static void cfq_insert_request(request_queue_t *q, struct request *rq)
{
+ struct cfq_data *cfqd = q->elevator->elevator_data;
struct cfq_rq *crq = RQ_DATA(rq);
struct cfq_queue *cfqq = crq->cfq_queue;
@@ -1827,66 +1652,43 @@ static void cfq_enqueue(struct cfq_data *cfqd, struct request *rq)
list_add_tail(&rq->queuelist, &cfqq->fifo);
- if (rq_mergeable(rq)) {
+ if (rq_mergeable(rq))
cfq_add_crq_hash(cfqd, crq);
- if (!cfqd->queue->last_merge)
- cfqd->queue->last_merge = rq;
- }
-
cfq_crq_enqueued(cfqd, cfqq, crq);
}
-static void
-cfq_insert_request(request_queue_t *q, struct request *rq, int where)
-{
- struct cfq_data *cfqd = q->elevator->elevator_data;
-
- switch (where) {
- case ELEVATOR_INSERT_BACK:
- while (cfq_dispatch_requests(q, INT_MAX, 1))
- ;
- list_add_tail(&rq->queuelist, &q->queue_head);
- /*
- * If we were idling with pending requests on
- * inactive cfqqs, force dispatching will
- * remove the idle timer and the queue won't
- * be kicked by __make_request() afterward.
- * Kick it here.
- */
- cfq_schedule_dispatch(cfqd);
- break;
- case ELEVATOR_INSERT_FRONT:
- list_add(&rq->queuelist, &q->queue_head);
- break;
- case ELEVATOR_INSERT_SORT:
- BUG_ON(!blk_fs_request(rq));
- cfq_enqueue(cfqd, rq);
- break;
- default:
- printk("%s: bad insert point %d\n", __FUNCTION__,where);
- return;
- }
-}
-
static void cfq_completed_request(request_queue_t *q, struct request *rq)
{
struct cfq_rq *crq = RQ_DATA(rq);
- struct cfq_queue *cfqq;
+ struct cfq_queue *cfqq = crq->cfq_queue;
+ struct cfq_data *cfqd = cfqq->cfqd;
+ const int sync = cfq_crq_is_sync(crq);
+ unsigned long now;
- if (unlikely(!blk_fs_request(rq)))
- return;
+ now = jiffies;
- cfqq = crq->cfq_queue;
+ WARN_ON(!cfqd->rq_in_driver);
+ WARN_ON(!cfqq->on_dispatch[sync]);
+ cfqd->rq_in_driver--;
+ cfqq->on_dispatch[sync]--;
- if (cfq_crq_in_flight(crq)) {
- const int sync = cfq_crq_is_sync(crq);
+ if (!cfq_class_idle(cfqq))
+ cfqd->last_end_request = now;
- WARN_ON(!cfqq->on_dispatch[sync]);
- cfqq->on_dispatch[sync]--;
+ 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);
+ }
}
- cfq_account_completion(cfqq, crq);
+ if (cfq_crq_is_sync(crq))
+ crq->io_context->last_end_request = now;
}
static struct request *
@@ -2075,7 +1877,7 @@ static void cfq_put_request(request_queue_t *q, struct request *rq)
*/
static int
cfq_set_request(request_queue_t *q, struct request *rq, struct bio *bio,
- int gfp_mask)
+ gfp_t gfp_mask)
{
struct cfq_data *cfqd = q->elevator->elevator_data;
struct task_struct *tsk = current;
@@ -2118,9 +1920,6 @@ cfq_set_request(request_queue_t *q, struct request *rq, struct bio *bio,
INIT_HLIST_NODE(&crq->hash);
crq->cfq_queue = cfqq;
crq->io_context = cic;
- cfq_clear_crq_in_flight(crq);
- cfq_clear_crq_in_driver(crq);
- cfq_clear_crq_requeued(crq);
if (rw == READ || process_sync(tsk))
cfq_mark_crq_is_sync(crq);
@@ -2201,7 +2000,7 @@ static void cfq_idle_slice_timer(unsigned long data)
* only expire and reinvoke request handler, if there are
* other queues with pending requests
*/
- if (!cfq_pending_requests(cfqd)) {
+ if (!cfqd->busy_queues) {
cfqd->idle_slice_timer.expires = min(now + cfqd->cfq_slice_idle, cfqq->slice_end);
add_timer(&cfqd->idle_slice_timer);
goto out_cont;
@@ -2576,10 +2375,9 @@ static struct elevator_type iosched_cfq = {
.elevator_merge_fn = cfq_merge,
.elevator_merged_fn = cfq_merged_request,
.elevator_merge_req_fn = cfq_merged_requests,
- .elevator_next_req_fn = cfq_next_request,
+ .elevator_dispatch_fn = cfq_dispatch_requests,
.elevator_add_req_fn = cfq_insert_request,
- .elevator_remove_req_fn = cfq_remove_request,
- .elevator_requeue_req_fn = cfq_requeue_request,
+ .elevator_activate_req_fn = cfq_activate_request,
.elevator_deactivate_req_fn = cfq_deactivate_request,
.elevator_queue_empty_fn = cfq_queue_empty,
.elevator_completed_req_fn = cfq_completed_request,
diff --git a/drivers/block/deadline-iosched.c b/drivers/block/deadline-iosched.c
index 52a3ae5289a..7929471d7df 100644
--- a/drivers/block/deadline-iosched.c
+++ b/drivers/block/deadline-iosched.c
@@ -50,7 +50,6 @@ struct deadline_data {
* next in sort order. read, write or both are NULL
*/
struct deadline_rq *next_drq[2];
- struct list_head *dispatch; /* driver dispatch queue */
struct list_head *hash; /* request hash */
unsigned int batching; /* number of sequential requests made */
sector_t last_sector; /* head position */
@@ -113,15 +112,6 @@ static inline void deadline_del_drq_hash(struct deadline_rq *drq)
__deadline_del_drq_hash(drq);
}
-static void
-deadline_remove_merge_hints(request_queue_t *q, struct deadline_rq *drq)
-{
- deadline_del_drq_hash(drq);
-
- if (q->last_merge == drq->request)
- q->last_merge = NULL;
-}
-
static inline void
deadline_add_drq_hash(struct deadline_data *dd, struct deadline_rq *drq)
{
@@ -239,10 +229,9 @@ deadline_del_drq_rb(struct deadline_data *dd, struct deadline_rq *drq)
dd->next_drq[data_dir] = rb_entry_drq(rbnext);
}
- if (ON_RB(&drq->rb_node)) {
- rb_erase(&drq->rb_node, DRQ_RB_ROOT(dd, drq));
- RB_CLEAR(&drq->rb_node);
- }
+ BUG_ON(!ON_RB(&drq->rb_node));
+ rb_erase(&drq->rb_node, DRQ_RB_ROOT(dd, drq));
+ RB_CLEAR(&drq->rb_node);
}
static struct request *
@@ -286,7 +275,7 @@ deadline_find_first_drq(struct deadline_data *dd, int data_dir)
/*
* add drq to rbtree and fifo
*/
-static inline void
+static void
deadline_add_request(struct request_queue *q, struct request *rq)
{
struct deadline_data *dd = q->elevator->elevator_data;
@@ -301,12 +290,8 @@ deadline_add_request(struct request_queue *q, struct request *rq)
drq->expires = jiffies + dd->fifo_expire[data_dir];
list_add_tail(&drq->fifo, &dd->fifo_list[data_dir]);
- if (rq_mergeable(rq)) {
+ if (rq_mergeable(rq))
deadline_add_drq_hash(dd, drq);
-
- if (!q->last_merge)
- q->last_merge = rq;
- }
}
/*
@@ -315,14 +300,11 @@ deadline_add_request(struct request_queue *q, struct request *rq)
static void deadline_remove_request(request_queue_t *q, struct request *rq)
{
struct deadline_rq *drq = RQ_DATA(rq);
+ struct deadline_data *dd = q->elevator->elevator_data;
- if (drq) {
- struct deadline_data *dd = q->elevator->elevator_data;
-
- list_del_init(&drq->fifo);
- deadline_remove_merge_hints(q, drq);
- deadline_del_drq_rb(dd, drq);
- }
+ list_del_init(&drq->fifo);
+ deadline_del_drq_rb(dd, drq);
+ deadline_del_drq_hash(drq);
}
static int
@@ -333,15 +315,6 @@ deadline_merge(request_queue_t *q, struct request **req, struct bio *bio)
int ret;
/*
- * try last_merge to avoid going to hash
- */
- ret = elv_try_last_merge(q, bio);
- if (ret != ELEVATOR_NO_MERGE) {
- __rq = q->last_merge;
- goto out_insert;
- }
-
- /*
* see if the merge hash can satisfy a back merge
*/
__rq = deadline_find_drq_hash(dd, bio->bi_sector);
@@ -373,8 +346,6 @@ deadline_merge(request_queue_t *q, struct request **req, struct bio *bio)
return ELEVATOR_NO_MERGE;
out:
- q->last_merge = __rq;
-out_insert:
if (ret)
deadline_hot_drq_hash(dd, RQ_DATA(__rq));
*req = __rq;
@@ -399,8 +370,6 @@ static void deadline_merged_request(request_queue_t *q, struct request *req)
deadline_del_drq_rb(dd, drq);
deadline_add_drq_rb(dd, drq);
}
-
- q->last_merge = req;
}
static void
@@ -452,7 +421,7 @@ deadline_move_to_dispatch(struct deadline_data *dd, struct deadline_rq *drq)
request_queue_t *q = drq->request->q;
deadline_remove_request(q, drq->request);
- list_add_tail(&drq->request->queuelist, dd->dispatch);
+ elv_dispatch_add_tail(q, drq->request);
}
/*
@@ -502,8 +471,9 @@ static inline int deadline_check_fifo(struct deadline_data *dd, int ddir)
* deadline_dispatch_requests selects the best request according to
* read/write expire, fifo_batch, etc
*/
-static int deadline_dispatch_requests(struct deadline_data *dd)
+static int deadline_dispatch_requests(request_queue_t *q, int force)
{
+ struct deadline_data *dd = q->elevator->elevator_data;
const int reads = !list_empty(&dd->fifo_list[READ]);
const int writes = !list_empty(&dd->fifo_list[WRITE]);
struct deadline_rq *drq;
@@ -597,65 +567,12 @@ dispatch_request:
return 1;
}
-static struct request *deadline_next_request(request_queue_t *q)
-{
- struct deadline_data *dd = q->elevator->elevator_data;
- struct request *rq;
-
- /*
- * if there are still requests on the dispatch queue, grab the first one
- */
- if (!list_empty(dd->dispatch)) {
-dispatch:
- rq = list_entry_rq(dd->dispatch->next);
- return rq;
- }
-
- if (deadline_dispatch_requests(dd))
- goto dispatch;
-
- return NULL;
-}
-
-static void
-deadline_insert_request(request_queue_t *q, struct request *rq, int where)
-{
- struct deadline_data *dd = q->elevator->elevator_data;
-
- /* barriers must flush the reorder queue */
- if (unlikely(rq->flags & (REQ_SOFTBARRIER | REQ_HARDBARRIER)
- && where == ELEVATOR_INSERT_SORT))
- where = ELEVATOR_INSERT_BACK;
-
- switch (where) {
- case ELEVATOR_INSERT_BACK:
- while (deadline_dispatch_requests(dd))
- ;
- list_add_tail(&rq->queuelist, dd->dispatch);
- break;
- case ELEVATOR_INSERT_FRONT:
- list_add(&rq->queuelist, dd->dispatch);
- break;
- case ELEVATOR_INSERT_SORT:
- BUG_ON(!blk_fs_request(rq));
- deadline_add_request(q, rq);
- break;
- default:
- printk("%s: bad insert point %d\n", __FUNCTION__,where);
- return;
- }
-}
-
static int deadline_queue_empty(request_queue_t *q)
{
struct deadline_data *dd = q->elevator->elevator_data;
- if (!list_empty(&dd->fifo_list[WRITE])
- || !list_empty(&dd->fifo_list[READ])
- || !list_empty(dd->dispatch))
- return 0;
-
- return 1;
+ return list_empty(&dd->fifo_list[WRITE])
+ && list_empty(&dd->fifo_list[READ]);
}
static struct request *
@@ -733,7 +650,6 @@ static int deadline_init_queue(request_queue_t *q, elevator_t *e)
INIT_LIST_HEAD(&dd->fifo_list[WRITE]);
dd->sort_list[READ] = RB_ROOT;
dd->sort_list[WRITE] = RB_ROOT;
- dd->dispatch = &q->queue_head;
dd->fifo_expire[READ] = read_expire;
dd->fifo_expire[WRITE] = write_expire;
dd->writes_starved = writes_starved;
@@ -748,15 +664,13 @@ static void deadline_put_request(request_queue_t *q, struct request *rq)
struct deadline_data *dd = q->elevator->elevator_data;
struct deadline_rq *drq = RQ_DATA(rq);
- if (drq) {
- mempool_free(drq, dd->drq_pool);
- rq->elevator_private = NULL;
- }
+ mempool_free(drq, dd->drq_pool);
+ rq->elevator_private = NULL;
}
static int
deadline_set_request(request_queue_t *q, struct request *rq, struct bio *bio,
- int gfp_mask)
+ gfp_t gfp_mask)
{
struct deadline_data *dd = q->elevator->elevator_data;
struct deadline_rq *drq;
@@ -917,9 +831,8 @@ static struct elevator_type iosched_deadline = {
.elevator_merge_fn = deadline_merge,
.elevator_merged_fn = deadline_merged_request,
.elevator_merge_req_fn = deadline_merged_requests,
- .elevator_next_req_fn = deadline_next_request,
- .elevator_add_req_fn = deadline_insert_request,
- .elevator_remove_req_fn = deadline_remove_request,
+ .elevator_dispatch_fn = deadline_dispatch_requests,
+ .elevator_add_req_fn = deadline_add_request,
.elevator_queue_empty_fn = deadline_queue_empty,
.elevator_former_req_fn = deadline_former_request,
.elevator_latter_req_fn = deadline_latter_request,
diff --git a/drivers/block/elevator.c b/drivers/block/elevator.c
index 98f0126a2de..55621d5c577 100644
--- a/drivers/block/elevator.c
+++ b/drivers/block/elevator.c
@@ -34,6 +34,7 @@
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/compiler.h>
+#include <linux/delay.h>
#include <asm/uaccess.h>
@@ -83,21 +84,11 @@ inline int elv_try_merge(struct request *__rq, struct bio *bio)
}
EXPORT_SYMBOL(elv_try_merge);
-inline int elv_try_last_merge(request_queue_t *q, struct bio *bio)
-{
- if (q->last_merge)
- return elv_try_merge(q->last_merge, bio);
-
- return ELEVATOR_NO_MERGE;
-}
-EXPORT_SYMBOL(elv_try_last_merge);
-
static struct elevator_type *elevator_find(const char *name)
{
struct elevator_type *e = NULL;
struct list_head *entry;
- spin_lock_irq(&elv_list_lock);
list_for_each(entry, &elv_list) {
struct elevator_type *__e;
@@ -108,7 +99,6 @@ static struct elevator_type *elevator_find(const char *name)
break;
}
}
- spin_unlock_irq(&elv_list_lock);
return e;
}
@@ -120,12 +110,15 @@ static void elevator_put(struct elevator_type *e)
static struct elevator_type *elevator_get(const char *name)
{
- struct elevator_type *e = elevator_find(name);
+ struct elevator_type *e;
- if (!e)
- return NULL;
- if (!try_module_get(e->elevator_owner))
- return NULL;
+ spin_lock_irq(&elv_list_lock);
+
+ e = elevator_find(name);
+ if (e && !try_module_get(e->elevator_owner))
+ e = NULL;
+
+ spin_unlock_irq(&elv_list_lock);
return e;
}
@@ -139,8 +132,6 @@ static int elevator_attach(request_queue_t *q, struct elevator_type *e,
eq->ops = &e->ops;
eq->elevator_type = e;
- INIT_LIST_HEAD(&q->queue_head);
- q->last_merge = NULL;
q->elevator = eq;
if (eq->ops->elevator_init_fn)
@@ -153,11 +144,15 @@ static char chosen_elevator[16];
static void elevator_setup_default(void)
{
+ struct elevator_type *e;
+
/*
* check if default is set and exists
*/
- if (chosen_elevator[0] && elevator_find(chosen_elevator))
+ if (chosen_elevator[0] && (e = elevator_get(chosen_elevator))) {
+ elevator_put(e);
return;
+ }
#if defined(CONFIG_IOSCHED_AS)
strcpy(chosen_elevator, "anticipatory");
@@ -186,6 +181,11 @@ int elevator_init(request_queue_t *q, char *name)
struct elevator_queue *eq;
int ret = 0;
+ INIT_LIST_HEAD(&q->queue_head);
+ q->last_merge = NULL;
+ q->end_sector = 0;
+ q->boundary_rq = NULL;
+
elevator_setup_default();
if (!name)
@@ -220,9 +220,52 @@ void elevator_exit(elevator_t *e)
kfree(e);
}
+/*
+ * Insert rq into dispatch queue of q. Queue lock must be held on
+ * entry. If sort != 0, rq is sort-inserted; otherwise, rq will be
+ * appended to the dispatch queue. To be used by specific elevators.
+ */
+void elv_dispatch_sort(request_queue_t *q, struct request *rq)
+{
+ sector_t boundary;
+ struct list_head *entry;
+
+ if (q->last_merge == rq)
+ q->last_merge = NULL;
+
+ boundary = q->end_sector;
+
+ list_for_each_prev(entry, &q->queue_head) {
+ struct request *pos = list_entry_rq(entry);
+
+ if (pos->flags & (REQ_SOFTBARRIER|REQ_HARDBARRIER|REQ_STARTED))
+ break;
+ if (rq->sector >= boundary) {
+ if (pos->sector < boundary)
+ continue;
+ } else {
+ if (pos->sector >= boundary)
+ break;
+ }
+ if (rq->sector >= pos->sector)
+ break;
+ }
+
+ list_add(&rq->queuelist, entry);
+}
+
int elv_merge(request_queue_t *q, struct request **req, struct bio *bio)
{
elevator_t *e = q->elevator;
+ int ret;
+
+ if (q->last_merge) {
+ ret = elv_try_merge(q->last_merge, bio);
+ if (ret != ELEVATOR_NO_MERGE) {
+ *req = q->last_merge;
+ return ret;
+ }
+ }
if (e->ops->elevator_merge_fn)
return e->ops->elevator_merge_fn(q, req, bio);
@@ -236,6 +279,8 @@ void elv_merged_request(request_queue_t *q, struct request *rq)
if (e->ops->elevator_merged_fn)
e->ops->elevator_merged_fn(q, rq);
+
+ q->last_merge = rq;
}
void elv_merge_requests(request_queue_t *q, struct request *rq,
@@ -243,20 +288,13 @@ void elv_merge_requests(request_queue_t *q, struct request *rq,
{
elevator_t *e = q->elevator;
- if (q->last_merge == next)
- q->last_merge = NULL;
-
if (e->ops->elevator_merge_req_fn)
e->ops->elevator_merge_req_fn(q, rq, next);
+
+ q->last_merge = rq;
}
-/*
- * For careful internal use by the block layer. Essentially the same as
- * a requeue in that it tells the io scheduler that this request is not
- * active in the driver or hardware anymore, but we don't want the request
- * added back to the scheduler. Function is not exported.
- */
-void elv_deactivate_request(request_queue_t *q, struct request *rq)
+void elv_requeue_request(request_queue_t *q, struct request *rq)
{
elevator_t *e = q->elevator;
@@ -264,19 +302,14 @@ void elv_deactivate_request(request_queue_t *q, struct request *rq)
* it already went through dequeue, we need to decrement the
* in_flight count again
*/
- if (blk_account_rq(rq))
+ if (blk_account_rq(rq)) {
q->in_flight--;
+ if (blk_sorted_rq(rq) && e->ops->elevator_deactivate_req_fn)
+ e->ops->elevator_deactivate_req_fn(q, rq);
+ }
rq->flags &= ~REQ_STARTED;
- if (e->ops->elevator_deactivate_req_fn)
- e->ops->elevator_deactivate_req_fn(q, rq);
-}
-
-void elv_requeue_request(request_queue_t *q, struct request *rq)
-{
- elv_deactivate_request(q, rq);
-
/*
* if this is the flush, requeue the original instead and drop the flush
*/
@@ -285,31 +318,27 @@ void elv_requeue_request(request_queue_t *q, struct request *rq)
rq = rq->end_io_data;
}
- /*
- * the request is prepped and may have some resources allocated.
- * allowing unprepped requests to pass this one may cause resource
- * deadlock. turn on softbarrier.
- */
- rq->flags |= REQ_SOFTBARRIER;
-
- /*
- * if iosched has an explicit requeue hook, then use that. otherwise
- * just put the request at the front of the queue
- */
- if (q->elevator->ops->elevator_requeue_req_fn)
- q->elevator->ops->elevator_requeue_req_fn(q, rq);
- else
- __elv_add_request(q, rq, ELEVATOR_INSERT_FRONT, 0);
+ __elv_add_request(q, rq, ELEVATOR_INSERT_FRONT, 0);
}
void __elv_add_request(request_queue_t *q, struct request *rq, int where,
int plug)
{
- /*
- * barriers implicitly indicate back insertion
- */
- if (rq->flags & (REQ_SOFTBARRIER | REQ_HARDBARRIER) &&
- where == ELEVATOR_INSERT_SORT)
+ if (rq->flags & (REQ_SOFTBARRIER | REQ_HARDBARRIER)) {
+ /*
+ * barriers implicitly indicate back insertion
+ */
+ if (where == ELEVATOR_INSERT_SORT)
+ where = ELEVATOR_INSERT_BACK;
+
+ /*
+ * this request is scheduling boundary, update end_sector
+ */
+ if (blk_fs_request(rq)) {
+ q->end_sector = rq_end_sector(rq);
+ q->boundary_rq = rq;
+ }
+ } else if (!(rq->flags & REQ_ELVPRIV) && where == ELEVATOR_INSERT_SORT)
where = ELEVATOR_INSERT_BACK;
if (plug)
@@ -317,23 +346,54 @@ void __elv_add_request(request_queue_t *q, struct request *rq, int where,
rq->q = q;
- if (!test_bit(QUEUE_FLAG_DRAIN, &q->queue_flags)) {
- q->elevator->ops->elevator_add_req_fn(q, rq, where);
+ switch (where) {
+ case ELEVATOR_INSERT_FRONT:
+ rq->flags |= REQ_SOFTBARRIER;
- if (blk_queue_plugged(q)) {
- int nrq = q->rq.count[READ] + q->rq.count[WRITE]
- - q->in_flight;
+ list_add(&rq->queuelist, &q->queue_head);
+ break;
- if (nrq >= q->unplug_thresh)
- __generic_unplug_device(q);
- }
- } else
+ case ELEVATOR_INSERT_BACK:
+ rq->flags |= REQ_SOFTBARRIER;
+
+ while (q->elevator->ops->elevator_dispatch_fn(q, 1))
+ ;
+ list_add_tail(&rq->queuelist, &q->queue_head);
/*
- * if drain is set, store the request "locally". when the drain
- * is finished, the requests will be handed ordered to the io
- * scheduler
+ * We kick the queue here for the following reasons.
+ * - The elevator might have returned NULL previously
+ * to delay requests and returned them now. As the
+ * queue wasn't empty before this request, ll_rw_blk
+ * won't run the queue on return, resulting in hang.
+ * - Usually, back inserted requests won't be merged
+ * with anything. There's no point in delaying queue
+ * processing.
*/
- list_add_tail(&rq->queuelist, &q->drain_list);
+ blk_remove_plug(q);
+ q->request_fn(q);
+ break;
+
+ case ELEVATOR_INSERT_SORT:
+ BUG_ON(!blk_fs_request(rq));
+ rq->flags |= REQ_SORTED;
+ q->elevator->ops->elevator_add_req_fn(q, rq);
+ if (q->last_merge == NULL && rq_mergeable(rq))
+ q->last_merge = rq;
+ break;
+
+ default:
+ printk(KERN_ERR "%s: bad insertion point %d\n",
+ __FUNCTION__, where);
+ BUG();
+ }
+
+ if (blk_queue_plugged(q)) {
+ int nrq = q->rq.count[READ] + q->rq.count[WRITE]
+ - q->in_flight;
+
+ if (nrq >= q->unplug_thresh)
+ __generic_unplug_device(q);
+ }
}
void elv_add_request(request_queue_t *q, struct request *rq, int where,
@@ -348,13 +408,19 @@ void elv_add_request(request_queue_t *q, struct request *rq, int where,
static inline struct request *__elv_next_request(request_queue_t *q)
{
- struct request *rq = q->elevator->ops->elevator_next_req_fn(q);
+ struct request *rq;
+
+ if (unlikely(list_empty(&q->queue_head) &&
+ !q->elevator->ops->elevator_dispatch_fn(q, 0)))
+ return NULL;
+
+ rq = list_entry_rq(q->queue_head.next);
/*
* if this is a barrier write and the device has to issue a
* flush sequence to support it, check how far we are
*/
- if (rq && blk_fs_request(rq) && blk_barrier_rq(rq)) {
+ if (blk_fs_request(rq) && blk_barrier_rq(rq)) {
BUG_ON(q->ordered == QUEUE_ORDERED_NONE);
if (q->ordered == QUEUE_ORDERED_FLUSH &&
@@ -371,15 +437,30 @@ struct request *elv_next_request(request_queue_t *q)
int ret;
while ((rq = __elv_next_request(q)) != NULL) {
- /*
- * just mark as started even if we don't start it, a request
- * that has been delayed should not be passed by new incoming
- * requests
- */
- rq->flags |= REQ_STARTED;
+ if (!(rq->flags & REQ_STARTED)) {
+ elevator_t *e = q->elevator;
- if (rq == q->last_merge)
- q->last_merge = NULL;
+ /*
+ * This is the first time the device driver
+ * sees this request (possibly after
+ * requeueing). Notify IO scheduler.
+ */
+ if (blk_sorted_rq(rq) &&
+ e->ops->elevator_activate_req_fn)
+ e->ops->elevator_activate_req_fn(q, rq);
+
+ /*
+ * just mark as started even if we don't start
+ * it, a request that has been delayed should
+ * not be passed by new incoming requests
+ */
+ rq->flags |= REQ_STARTED;
+ }
+
+ if (!q->boundary_rq || q->boundary_rq == rq) {
+ q->end_sector = rq_end_sector(rq);
+ q->boundary_rq = NULL;
+ }
if ((rq->flags & REQ_DONTPREP) || !q->prep_rq_fn)
break;
@@ -391,9 +472,9 @@ struct request *elv_next_request(request_queue_t *q)
/*
* the request may have been (partially) prepped.
* we need to keep this request in the front to
- * avoid resource deadlock. turn on softbarrier.
+ * avoid resource deadlock. REQ_STARTED will
+ * prevent other fs requests from passing this one.
*/
- rq->flags |= REQ_SOFTBARRIER;
rq = NULL;
break;
} else if (ret == BLKPREP_KILL) {
@@ -416,42 +497,32 @@ struct request *elv_next_request(request_queue_t *q)
return rq;
}
-void elv_remove_request(request_queue_t *q, struct request *rq)
+void elv_dequeue_request(request_queue_t *q, struct request *rq)
{
- elevator_t *e = q->elevator;
+ BUG_ON(list_empty(&rq->queuelist));
+
+ list_del_init(&rq->queuelist);
/*
* the time frame between a request being removed from the lists
* and to it is freed is accounted as io that is in progress at
- * the driver side. note that we only account requests that the
- * driver has seen (REQ_STARTED set), to avoid false accounting
- * for request-request merges
+ * the driver side.
*/
if (blk_account_rq(rq))
q->in_flight++;
-
- /*
- * the main clearing point for q->last_merge is on retrieval of
- * request by driver (it calls elv_next_request()), but it _can_
- * also happen here if a request is added to the queue but later
- * deleted without ever being given to driver (merged with another
- * request).
- */
- if (rq == q->last_merge)
- q->last_merge = NULL;
-
- if (e->ops->elevator_remove_req_fn)
- e->ops->elevator_remove_req_fn(q, rq);
}
int elv_queue_empty(request_queue_t *q)
{
elevator_t *e = q->elevator;
+ if (!list_empty(&q->queue_head))
+ return 0;
+
if (e->ops->elevator_queue_empty_fn)
return e->ops->elevator_queue_empty_fn(q);
- return list_empty(&q->queue_head);
+ return 1;
}
struct request *elv_latter_request(request_queue_t *q, struct request *rq)
@@ -487,7 +558,7 @@ struct request *elv_former_request(request_queue_t *q, struct request *rq)
}
int elv_set_request(request_queue_t *q, struct request *rq, struct bio *bio,
- int gfp_mask)
+ gfp_t gfp_mask)
{
elevator_t *e = q->elevator;
@@ -523,11 +594,11 @@ void elv_completed_request(request_queue_t *q, struct request *rq)
/*
* request is released from the driver, io must be done
*/
- if (blk_account_rq(rq))
+ if (blk_account_rq(rq)) {
q->in_flight--;
-
- if (e->ops->elevator_completed_req_fn)
- e->ops->elevator_completed_req_fn(q, rq);
+ if (blk_sorted_rq(rq) && e->ops->elevator_completed_req_fn)
+ e->ops->elevator_completed_req_fn(q, rq);
+ }
}
int elv_register_queue(struct request_queue *q)
@@ -555,10 +626,9 @@ void elv_unregister_queue(struct request_queue *q)
int elv_register(struct elevator_type *e)
{
+ spin_lock_irq(&elv_list_lock);
if (elevator_find(e->elevator_name))
BUG();
-
- spin_lock_irq(&elv_list_lock);
list_add_tail(&e->list, &elv_list);
spin_unlock_irq(&elv_list_lock);
@@ -582,25 +652,36 @@ EXPORT_SYMBOL_GPL(elv_unregister);
* switch to new_e io scheduler. be careful not to introduce deadlocks -
* we don't free the old io scheduler, before we have allocated what we
* need for the new one. this way we have a chance of going back to the old
- * one, if the new one fails init for some reason. we also do an intermediate
- * switch to noop to ensure safety with stack-allocated requests, since they
- * don't originate from the block layer allocator. noop is safe here, because
- * it never needs to touch the elevator itself for completion events. DRAIN
- * flags will make sure we don't touch it for additions either.
+ * one, if the new one fails init for some reason.
*/
static void elevator_switch(request_queue_t *q, struct elevator_type *new_e)
{
- elevator_t *e = kmalloc(sizeof(elevator_t), GFP_KERNEL);
- struct elevator_type *noop_elevator = NULL;
- elevator_t *old_elevator;
+ elevator_t *old_elevator, *e;
+ /*
+ * Allocate new elevator
+ */
+ e = kmalloc(sizeof(elevator_t), GFP_KERNEL);
if (!e)
goto error;
/*
- * first step, drain requests from the block freelist
+ * Turn on BYPASS and drain all requests w/ elevator private data
*/
- blk_wait_queue_drained(q, 0);
+ spin_lock_irq(q->queue_lock);
+
+ set_bit(QUEUE_FLAG_ELVSWITCH, &q->queue_flags);
+
+ while (q->elevator->ops->elevator_dispatch_fn(q, 1))
+ ;
+
+ while (q->rq.elvpriv) {
+ spin_unlock_irq(q->queue_lock);
+ msleep(10);
+ spin_lock_irq(q->queue_lock);
+ }
+
+ spin_unlock_irq(q->queue_lock);
/*
* unregister old elevator data
@@ -609,18 +690,6 @@ static void elevator_switch(request_queue_t *q, struct elevator_type *new_e)
old_elevator = q->elevator;
/*
- * next step, switch to noop since it uses no private rq structures
- * and doesn't allocate any memory for anything. then wait for any
- * non-fs requests in-flight
- */
- noop_elevator = elevator_get("noop");
- spin_lock_irq(q->queue_lock);
- elevator_attach(q, noop_elevator, e);
- spin_unlock_irq(q->queue_lock);
-
- blk_wait_queue_drained(q, 1);
-
- /*
* attach and start new elevator
*/
if (elevator_attach(q, new_e, e))
@@ -630,11 +699,10 @@ static void elevator_switch(request_queue_t *q, struct elevator_type *new_e)
goto fail_register;
/*
- * finally exit old elevator and start queue again
+ * finally exit old elevator and turn off BYPASS.
*/
elevator_exit(old_elevator);
- blk_finish_queue_drain(q);
- elevator_put(noop_elevator);
+ clear_bit(QUEUE_FLAG_ELVSWITCH, &q->queue_flags);
return;
fail_register:
@@ -643,13 +711,13 @@ fail_register:
* one again (along with re-adding the sysfs dir)
*/
elevator_exit(e);
+ e = NULL;
fail:
q->elevator = old_elevator;
elv_register_queue(q);
- blk_finish_queue_drain(q);
+ clear_bit(QUEUE_FLAG_ELVSWITCH, &q->queue_flags);
+ kfree(e);
error:
- if (noop_elevator)
- elevator_put(noop_elevator);
elevator_put(new_e);
printk(KERN_ERR "elevator: switch to %s failed\n",new_e->elevator_name);
}
@@ -701,11 +769,12 @@ ssize_t elv_iosched_show(request_queue_t *q, char *name)
return len;
}
+EXPORT_SYMBOL(elv_dispatch_sort);
EXPORT_SYMBOL(elv_add_request);
EXPORT_SYMBOL(__elv_add_request);
EXPORT_SYMBOL(elv_requeue_request);
EXPORT_SYMBOL(elv_next_request);
-EXPORT_SYMBOL(elv_remove_request);
+EXPORT_SYMBOL(elv_dequeue_request);
EXPORT_SYMBOL(elv_queue_empty);
EXPORT_SYMBOL(elv_completed_request);
EXPORT_SYMBOL(elevator_exit);
diff --git a/drivers/block/ll_rw_blk.c b/drivers/block/ll_rw_blk.c
index baedac52294..0af73512b9a 100644
--- a/drivers/block/ll_rw_blk.c
+++ b/drivers/block/ll_rw_blk.c
@@ -263,8 +263,6 @@ void blk_queue_make_request(request_queue_t * q, make_request_fn * mfn)
blk_queue_bounce_limit(q, BLK_BOUNCE_HIGH);
blk_queue_activity_fn(q, NULL, NULL);
-
- INIT_LIST_HEAD(&q->drain_list);
}
EXPORT_SYMBOL(blk_queue_make_request);
@@ -353,6 +351,8 @@ static void blk_pre_flush_end_io(struct request *flush_rq)
struct request *rq = flush_rq->end_io_data;
request_queue_t *q = rq->q;
+ elv_completed_request(q, flush_rq);
+
rq->flags |= REQ_BAR_PREFLUSH;
if (!flush_rq->errors)
@@ -369,6 +369,8 @@ static void blk_post_flush_end_io(struct request *flush_rq)
struct request *rq = flush_rq->end_io_data;
request_queue_t *q = rq->q;
+ elv_completed_request(q, flush_rq);
+
rq->flags |= REQ_BAR_POSTFLUSH;
q->end_flush_fn(q, flush_rq);
@@ -408,8 +410,6 @@ struct request *blk_start_pre_flush(request_queue_t *q, struct request *rq)
if (!list_empty(&rq->queuelist))
blkdev_dequeue_request(rq);
- elv_deactivate_request(q, rq);
-
flush_rq->end_io_data = rq;
flush_rq->end_io = blk_pre_flush_end_io;
@@ -1040,6 +1040,7 @@ EXPORT_SYMBOL(blk_queue_invalidate_tags);
static char *rq_flags[] = {
"REQ_RW",
"REQ_FAILFAST",
+ "REQ_SORTED",
"REQ_SOFTBARRIER",
"REQ_HARDBARRIER",
"REQ_CMD",
@@ -1047,6 +1048,7 @@ static char *rq_flags[] = {
"REQ_STARTED",
"REQ_DONTPREP",
"REQ_QUEUED",
+ "REQ_ELVPRIV",
"REQ_PC",
"REQ_BLOCK_PC",
"REQ_SENSE",
@@ -1637,9 +1639,9 @@ static int blk_init_free_list(request_queue_t *q)
rl->count[READ] = rl->count[WRITE] = 0;
rl->starved[READ] = rl->starved[WRITE] = 0;
+ rl->elvpriv = 0;
init_waitqueue_head(&rl->wait[READ]);
init_waitqueue_head(&rl->wait[WRITE]);
- init_waitqueue_head(&rl->drain);
rl->rq_pool = mempool_create_node(BLKDEV_MIN_RQ, mempool_alloc_slab,
mempool_free_slab, request_cachep, q->node);
@@ -1652,13 +1654,13 @@ static int blk_init_free_list(request_queue_t *q)
static int __make_request(request_queue_t *, struct bio *);
-request_queue_t *blk_alloc_queue(int gfp_mask)
+request_queue_t *blk_alloc_queue(gfp_t gfp_mask)
{
return blk_alloc_queue_node(gfp_mask, -1);
}
EXPORT_SYMBOL(blk_alloc_queue);
-request_queue_t *blk_alloc_queue_node(int gfp_mask, int node_id)
+request_queue_t *blk_alloc_queue_node(gfp_t gfp_mask, int node_id)
{
request_queue_t *q;
@@ -1782,12 +1784,14 @@ EXPORT_SYMBOL(blk_get_queue);
static inline void blk_free_request(request_queue_t *q, struct request *rq)
{
- elv_put_request(q, rq);
+ if (rq->flags & REQ_ELVPRIV)
+ elv_put_request(q, rq);
mempool_free(rq, q->rq.rq_pool);
}
static inline struct request *
-blk_alloc_request(request_queue_t *q, int rw, struct bio *bio, int gfp_mask)
+blk_alloc_request(request_queue_t *q, int rw, struct bio *bio,
+ int priv, gfp_t gfp_mask)
{
struct request *rq = mempool_alloc(q->rq.rq_pool, gfp_mask);
@@ -1800,11 +1804,15 @@ blk_alloc_request(request_queue_t *q, int rw, struct bio *bio, int gfp_mask)
*/
rq->flags = rw;
- if (!elv_set_request(q, rq, bio, gfp_mask))
- return rq;
+ if (priv) {
+ if (unlikely(elv_set_request(q, rq, bio, gfp_mask))) {
+ mempool_free(rq, q->rq.rq_pool);
+ return NULL;
+ }
+ rq->flags |= REQ_ELVPRIV;
+ }
- mempool_free(rq, q->rq.rq_pool);
- return NULL;
+ return rq;
}
/*
@@ -1860,22 +1868,18 @@ static void __freed_request(request_queue_t *q, int rw)
* A request has just been released. Account for it, update the full and
* congestion status, wake up any waiters. Called under q->queue_lock.
*/
-static void freed_request(request_queue_t *q, int rw)
+static void freed_request(request_queue_t *q, int rw, int priv)
{
struct request_list *rl = &q->rq;
rl->count[rw]--;
+ if (priv)
+ rl->elvpriv--;
__freed_request(q, rw);
if (unlikely(rl->starved[rw ^ 1]))
__freed_request(q, rw ^ 1);
-
- if (!rl->count[READ] && !rl->count[WRITE]) {
- smp_mb();
- if (unlikely(waitqueue_active(&rl->drain)))
- wake_up(&rl->drain);
- }
}
#define blkdev_free_rq(list) list_entry((list)->next, struct request, queuelist)
@@ -1885,14 +1889,12 @@ static void freed_request(request_queue_t *q, int rw)
* Returns !NULL on success, with queue_lock *not held*.
*/
static struct request *get_request(request_queue_t *q, int rw, struct bio *bio,
- int gfp_mask)
+ gfp_t gfp_mask)
{
struct request *rq = NULL;
struct request_list *rl = &q->rq;
struct io_context *ioc = current_io_context(GFP_ATOMIC);
-
- if (unlikely(test_bit(QUEUE_FLAG_DRAIN, &q->queue_flags)))
- goto out;
+ int priv;
if (rl->count[rw]+1 >= q->nr_requests) {
/*
@@ -1937,9 +1939,14 @@ get_rq:
rl->starved[rw] = 0;
if (rl->count[rw] >= queue_congestion_on_threshold(q))
set_queue_congested(q, rw);
+
+ priv = !test_bit(QUEUE_FLAG_ELVSWITCH, &q->queue_flags);
+ if (priv)
+ rl->elvpriv++;
+
spin_unlock_irq(q->queue_lock);
- rq = blk_alloc_request(q, rw, bio, gfp_mask);
+ rq = blk_alloc_request(q, rw, bio, priv, gfp_mask);
if (!rq) {
/*
* Allocation failed presumably due to memory. Undo anything
@@ -1949,7 +1956,7 @@ get_rq:
* wait queue, but this is pretty rare.
*/
spin_lock_irq(q->queue_lock);
- freed_request(q, rw);
+ freed_request(q, rw, priv);
/*
* in the very unlikely event that allocation failed and no
@@ -2019,7 +2026,7 @@ static struct request *get_request_wait(request_queue_t *q, int rw,
return rq;
}
-struct request *blk_get_request(request_queue_t *q, int rw, int gfp_mask)
+struct request *blk_get_request(request_queue_t *q, int rw, gfp_t gfp_mask)
{
struct request *rq;
@@ -2251,7 +2258,7 @@ EXPORT_SYMBOL(blk_rq_unmap_user);
* @gfp_mask: memory allocation flags
*/
int blk_rq_map_kern(request_queue_t *q, struct request *rq, void *kbuf,
- unsigned int len, unsigned int gfp_mask)
+ unsigned int len, gfp_t gfp_mask)
{
struct bio *bio;
@@ -2433,13 +2440,15 @@ void disk_round_stats(struct gendisk *disk)
{
unsigned long now = jiffies;
- __disk_stat_add(disk, time_in_queue,
- disk->in_flight * (now - disk->stamp));
- disk->stamp = now;
+ if (now == disk->stamp)
+ return;
- if (disk->in_flight)
- __disk_stat_add(disk, io_ticks, (now - disk->stamp_idle));
- disk->stamp_idle = now;
+ if (disk->in_flight) {
+ __disk_stat_add(disk, time_in_queue,
+ disk->in_flight * (now - disk->stamp));
+ __disk_stat_add(disk, io_ticks, (now - disk->stamp));
+ }
+ disk->stamp = now;
}
/*
@@ -2454,6 +2463,8 @@ static void __blk_put_request(request_queue_t *q, struct request *req)
if (unlikely(--req->ref_count))
return;
+ elv_completed_request(q, req);
+
req->rq_status = RQ_INACTIVE;
req->rl = NULL;
@@ -2463,26 +2474,25 @@ static void __blk_put_request(request_queue_t *q, struct request *req)
*/
if (rl) {
int rw = rq_data_dir(req);
-
- elv_completed_request(q, req);
+ int priv = req->flags & REQ_ELVPRIV;
BUG_ON(!list_empty(&req->queuelist));
blk_free_request(q, req);
- freed_request(q, rw);
+ freed_request(q, rw, priv);
}
}
void blk_put_request(struct request *req)
{
+ unsigned long flags;
+ request_queue_t *q = req->q;
+
/*
- * if req->rl isn't set, this request didnt originate from the
- * block layer, so it's safe to just disregard it
+ * Gee, IDE calls in w/ NULL q. Fix IDE and remove the
+ * following if (q) test.
*/
- if (req->rl) {
- unsigned long flags;
- request_queue_t *q = req->q;
-
+ if (q) {
spin_lock_irqsave(q->queue_lock, flags);
__blk_put_request(q, req);
spin_unlock_irqrestore(q->queue_lock, flags);
@@ -2797,97 +2807,6 @@ static inline void blk_partition_remap(struct bio *bio)
}
}
-void blk_finish_queue_drain(request_queue_t *q)
-{
- struct request_list *rl = &q->rq;
- struct request *rq;
- int requeued = 0;
-
- spin_lock_irq(q->queue_lock);
- clear_bit(QUEUE_FLAG_DRAIN, &q->queue_flags);
-
- while (!list_empty(&q->drain_list)) {
- rq = list_entry_rq(q->drain_list.next);
-
- list_del_init(&rq->queuelist);
- elv_requeue_request(q, rq);
- requeued++;
- }
-
- if (requeued)
- q->request_fn(q);
-
- spin_unlock_irq(q->queue_lock);
-
- wake_up(&rl->wait[0]);
- wake_up(&rl->wait[1]);
- wake_up(&rl->drain);
-}
-
-static int wait_drain(request_queue_t *q, struct request_list *rl, int dispatch)
-{
- int wait = rl->count[READ] + rl->count[WRITE];
-
- if (dispatch)
- wait += !list_empty(&q->queue_head);
-
- return wait;
-}
-
-/*
- * We rely on the fact that only requests allocated through blk_alloc_request()
- * have io scheduler private data structures associated with them. Any other
- * type of request (allocated on stack or through kmalloc()) should not go
- * to the io scheduler core, but be attached to the queue head instead.
- */
-void blk_wait_queue_drained(request_queue_t *q, int wait_dispatch)
-{
- struct request_list *rl = &q->rq;
- DEFINE_WAIT(wait);
-
- spin_lock_irq(q->queue_lock);
- set_bit(QUEUE_FLAG_DRAIN, &q->queue_flags);
-
- while (wait_drain(q, rl, wait_dispatch)) {
- prepare_to_wait(&rl->drain, &wait, TASK_UNINTERRUPTIBLE);
-
- if (wait_drain(q, rl, wait_dispatch)) {
- __generic_unplug_device(q);
- spin_unlock_irq(q->queue_lock);
- io_schedule();
- spin_lock_irq(q->queue_lock);
- }
-
- finish_wait(&rl->drain, &wait);
- }
-
- spin_unlock_irq(q->queue_lock);
-}
-
-/*
- * block waiting for the io scheduler being started again.
- */
-static inline void block_wait_queue_running(request_queue_t *q)
-{
- DEFINE_WAIT(wait);
-
- while (unlikely(test_bit(QUEUE_FLAG_DRAIN, &q->queue_flags))) {
- struct request_list *rl = &q->rq;
-
- prepare_to_wait_exclusive(&rl->drain, &wait,
- TASK_UNINTERRUPTIBLE);
-
- /*
- * re-check the condition. avoids using prepare_to_wait()
- * in the fast path (queue is running)
- */
- if (test_bit(QUEUE_FLAG_DRAIN, &q->queue_flags))
- io_schedule();
-
- finish_wait(&rl->drain, &wait);
- }
-}
-
static void handle_bad_sector(struct bio *bio)
{
char b[BDEVNAME_SIZE];
@@ -2983,8 +2902,6 @@ end_io:
if (unlikely(test_bit(QUEUE_FLAG_DEAD, &q->queue_flags)))
goto end_io;
- block_wait_queue_running(q);
-
/*
* If this device has partitions, remap block n
* of partition p to block n+start(p) of the disk.
@@ -3393,7 +3310,7 @@ void exit_io_context(void)
* but since the current task itself holds a reference, the context can be
* used in general code, so long as it stays within `current` context.
*/
-struct io_context *current_io_context(int gfp_flags)
+struct io_context *current_io_context(gfp_t gfp_flags)
{
struct task_struct *tsk = current;
struct io_context *ret;
@@ -3424,7 +3341,7 @@ EXPORT_SYMBOL(current_io_context);
*
* This is always called in the context of the task which submitted the I/O.
*/
-struct io_context *get_io_context(int gfp_flags)
+struct io_context *get_io_context(gfp_t gfp_flags)
{
struct io_context *ret;
ret = current_io_context(gfp_flags);
diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index b35e08876dd..96c664af8d0 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -881,7 +881,7 @@ loop_init_xfer(struct loop_device *lo, struct loop_func_table *xfer,
static int loop_clr_fd(struct loop_device *lo, struct block_device *bdev)
{
struct file *filp = lo->lo_backing_file;
- int gfp = lo->old_gfp_mask;
+ gfp_t gfp = lo->old_gfp_mask;
if (lo->lo_state != Lo_bound)
return -ENXIO;
diff --git a/drivers/block/noop-iosched.c b/drivers/block/noop-iosched.c
index b1730b62c37..f56b8edb06e 100644
--- a/drivers/block/noop-iosched.c
+++ b/drivers/block/noop-iosched.c
@@ -7,57 +7,19 @@
#include <linux/module.h>
#include <linux/init.h>
-/*
- * See if we can find a request that this buffer can be coalesced with.
- */
-static int elevator_noop_merge(request_queue_t *q, struct request **req,
- struct bio *bio)
-{
- int ret;
-
- ret = elv_try_last_merge(q, bio);
- if (ret != ELEVATOR_NO_MERGE)
- *req = q->last_merge;
-
- return ret;
-}
-
-static void elevator_noop_merge_requests(request_queue_t *q, struct request *req,
- struct request *next)
-{
- list_del_init(&next->queuelist);
-}
-
-static void elevator_noop_add_request(request_queue_t *q, struct request *rq,
- int where)
+static void elevator_noop_add_request(request_queue_t *q, struct request *rq)
{
- if (where == ELEVATOR_INSERT_FRONT)
- list_add(&rq->queuelist, &q->queue_head);
- else
- list_add_tail(&rq->queuelist, &q->queue_head);
-
- /*
- * new merges must not precede this barrier
- */
- if (rq->flags & REQ_HARDBARRIER)
- q->last_merge = NULL;
- else if (!q->last_merge)
- q->last_merge = rq;
+ elv_dispatch_add_tail(q, rq);
}
-static struct request *elevator_noop_next_request(request_queue_t *q)
+static int elevator_noop_dispatch(request_queue_t *q, int force)
{
- if (!list_empty(&q->queue_head))
- return list_entry_rq(q->queue_head.next);
-
- return NULL;
+ return 0;
}
static struct elevator_type elevator_noop = {
.ops = {
- .elevator_merge_fn = elevator_noop_merge,
- .elevator_merge_req_fn = elevator_noop_merge_requests,
- .elevator_next_req_fn = elevator_noop_next_request,
+ .elevator_dispatch_fn = elevator_noop_dispatch,
.elevator_add_req_fn = elevator_noop_add_request,
},
.elevator_name = "noop",
diff --git a/drivers/block/rd.c b/drivers/block/rd.c
index 145c1fbffe0..68c60a5bcda 100644
--- a/drivers/block/rd.c
+++ b/drivers/block/rd.c
@@ -348,7 +348,7 @@ static int rd_open(struct inode *inode, struct file *filp)
struct block_device *bdev = inode->i_bdev;
struct address_space *mapping;
unsigned bsize;
- int gfp_mask;
+ gfp_t gfp_mask;
inode = igrab(bdev->bd_inode);
rd_bdev[unit] = bdev;
diff --git a/drivers/block/sx8.c b/drivers/block/sx8.c
index d57007b92f7..1ded3b43345 100644
--- a/drivers/block/sx8.c
+++ b/drivers/block/sx8.c
@@ -1,7 +1,7 @@
/*
* sx8.c: Driver for Promise SATA SX8 looks-like-I2O hardware
*
- * Copyright 2004 Red Hat, Inc.
+ * Copyright 2004-2005 Red Hat, Inc.
*
* Author/maintainer: Jeff Garzik <jgarzik@pobox.com>
*
@@ -31,10 +31,6 @@
#include <asm/semaphore.h>
#include <asm/uaccess.h>
-MODULE_AUTHOR("Jeff Garzik");
-MODULE_LICENSE("GPL");
-MODULE_DESCRIPTION("Promise SATA SX8 block driver");
-
#if 0
#define CARM_DEBUG
#define CARM_VERBOSE_DEBUG
@@ -45,9 +41,35 @@ MODULE_DESCRIPTION("Promise SATA SX8 block driver");
#undef CARM_NDEBUG
#define DRV_NAME "sx8"
-#define DRV_VERSION "0.8"
+#define DRV_VERSION "1.0"
#define PFX DRV_NAME ": "
+MODULE_AUTHOR("Jeff Garzik");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Promise SATA SX8 block driver");
+MODULE_VERSION(DRV_VERSION);
+
+/*
+ * SX8 hardware has a single message queue for all ATA ports.
+ * When this driver was written, the hardware (firmware?) would
+ * corrupt data eventually, if more than one request was outstanding.
+ * As one can imagine, having 8 ports bottlenecking on a single
+ * command hurts performance.
+ *
+ * Based on user reports, later versions of the hardware (firmware?)
+ * seem to be able to survive with more than one command queued.
+ *
+ * Therefore, we default to the safe option -- 1 command -- but
+ * allow the user to increase this.
+ *
+ * SX8 should be able to support up to ~60 queued commands (CARM_MAX_REQ),
+ * but problems seem to occur when you exceed ~30, even on newer hardware.
+ */
+static int max_queue = 1;
+module_param(max_queue, int, 0444);
+MODULE_PARM_DESC(max_queue, "Maximum number of queued commands. (min==1, max==30, safe==1)");
+
+
#define NEXT_RESP(idx) ((idx + 1) % RMSG_Q_LEN)
/* 0xf is just arbitrary, non-zero noise; this is sorta like poisoning */
@@ -90,12 +112,10 @@ enum {
/* command message queue limits */
CARM_MAX_REQ = 64, /* max command msgs per host */
- CARM_MAX_Q = 1, /* one command at a time */
CARM_MSG_LOW_WATER = (CARM_MAX_REQ / 4), /* refill mark */
/* S/G limits, host-wide and per-request */
CARM_MAX_REQ_SG = 32, /* max s/g entries per request */
- CARM_SG_BOUNDARY = 0xffffUL, /* s/g segment boundary */
CARM_MAX_HOST_SG = 600, /* max s/g entries per host */
CARM_SG_LOW_WATER = (CARM_MAX_HOST_SG / 4), /* re-fill mark */
@@ -181,6 +201,10 @@ enum {
FL_DYN_MAJOR = (1 << 17),
};
+enum {
+ CARM_SG_BOUNDARY = 0xffffUL, /* s/g segment boundary */
+};
+
enum scatter_gather_types {
SGT_32BIT = 0,
SGT_64BIT = 1,
@@ -218,7 +242,6 @@ static const char *state_name[] = {
struct carm_port {
unsigned int port_no;
- unsigned int n_queued;
struct gendisk *disk;
struct carm_host *host;
@@ -448,7 +471,7 @@ static inline int carm_lookup_bucket(u32 msg_size)
for (i = 0; i < ARRAY_SIZE(msg_sizes); i++)
if (msg_size <= msg_sizes[i])
return i;
-
+
return -ENOENT;
}
@@ -509,7 +532,7 @@ static struct carm_request *carm_get_request(struct carm_host *host)
if (host->hw_sg_used >= (CARM_MAX_HOST_SG - CARM_MAX_REQ_SG))
return NULL;
- for (i = 0; i < CARM_MAX_Q; i++)
+ for (i = 0; i < max_queue; i++)
if ((host->msg_alloc & (1ULL << i)) == 0) {
struct carm_request *crq = &host->req[i];
crq->port = NULL;
@@ -521,14 +544,14 @@ static struct carm_request *carm_get_request(struct carm_host *host)
assert(host->n_msgs <= CARM_MAX_REQ);
return crq;
}
-
+
DPRINTK("no request available, returning NULL\n");
return NULL;
}
static int carm_put_request(struct carm_host *host, struct carm_request *crq)
{
- assert(crq->tag < CARM_MAX_Q);
+ assert(crq->tag < max_queue);
if (unlikely((host->msg_alloc & (1ULL << crq->tag)) == 0))
return -EINVAL; /* tried to clear a tag that was not active */
@@ -791,7 +814,7 @@ static inline void carm_end_rq(struct carm_host *host, struct carm_request *crq,
int is_ok)
{
carm_end_request_queued(host, crq, is_ok);
- if (CARM_MAX_Q == 1)
+ if (max_queue == 1)
carm_round_robin(host);
else if ((host->n_msgs <= CARM_MSG_LOW_WATER) &&
(host->hw_sg_used <= CARM_SG_LOW_WATER)) {
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-14 09:57:51 +0000