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-rw-r--r--block/cfq-iosched.c626
1 files changed, 116 insertions, 510 deletions
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index 3548705b04e..ee55019066a 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -14,6 +14,7 @@
#include <linux/rbtree.h>
#include <linux/ioprio.h>
#include <linux/blktrace_api.h>
+#include "blk.h"
#include "cfq.h"
/*
@@ -53,20 +54,11 @@ static const int cfq_hist_divisor = 4;
#define CFQQ_SECT_THR_NONROT (sector_t)(2 * 32)
#define CFQQ_SEEKY(cfqq) (hweight32(cfqq->seek_history) > 32/8)
-#define RQ_CIC(rq) \
- ((struct cfq_io_context *) (rq)->elevator_private[0])
-#define RQ_CFQQ(rq) (struct cfq_queue *) ((rq)->elevator_private[1])
-#define RQ_CFQG(rq) (struct cfq_group *) ((rq)->elevator_private[2])
+#define RQ_CIC(rq) icq_to_cic((rq)->elv.icq)
+#define RQ_CFQQ(rq) (struct cfq_queue *) ((rq)->elv.priv[0])
+#define RQ_CFQG(rq) (struct cfq_group *) ((rq)->elv.priv[1])
static struct kmem_cache *cfq_pool;
-static struct kmem_cache *cfq_ioc_pool;
-
-static DEFINE_PER_CPU(unsigned long, cfq_ioc_count);
-static struct completion *ioc_gone;
-static DEFINE_SPINLOCK(ioc_gone_lock);
-
-static DEFINE_SPINLOCK(cic_index_lock);
-static DEFINE_IDA(cic_index_ida);
#define CFQ_PRIO_LISTS IOPRIO_BE_NR
#define cfq_class_idle(cfqq) ((cfqq)->ioprio_class == IOPRIO_CLASS_IDLE)
@@ -75,6 +67,14 @@ static DEFINE_IDA(cic_index_ida);
#define sample_valid(samples) ((samples) > 80)
#define rb_entry_cfqg(node) rb_entry((node), struct cfq_group, rb_node)
+struct cfq_ttime {
+ unsigned long last_end_request;
+
+ unsigned long ttime_total;
+ unsigned long ttime_samples;
+ unsigned long ttime_mean;
+};
+
/*
* 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
@@ -216,6 +216,12 @@ struct cfq_group {
struct cfq_ttime ttime;
};
+struct cfq_io_cq {
+ struct io_cq icq; /* must be the first member */
+ struct cfq_queue *cfqq[2];
+ struct cfq_ttime ttime;
+};
+
/*
* Per block device queue structure
*/
@@ -267,7 +273,7 @@ struct cfq_data {
struct work_struct unplug_work;
struct cfq_queue *active_queue;
- struct cfq_io_context *active_cic;
+ struct cfq_io_cq *active_cic;
/*
* async queue for each priority case
@@ -290,9 +296,6 @@ struct cfq_data {
unsigned int cfq_group_idle;
unsigned int cfq_latency;
- unsigned int cic_index;
- struct list_head cic_list;
-
/*
* Fallback dummy cfqq for extreme OOM conditions
*/
@@ -464,37 +467,35 @@ static inline int cfqg_busy_async_queues(struct cfq_data *cfqd,
static void cfq_dispatch_insert(struct request_queue *, struct request *);
static struct cfq_queue *cfq_get_queue(struct cfq_data *, bool,
struct io_context *, gfp_t);
-static struct cfq_io_context *cfq_cic_lookup(struct cfq_data *,
- struct io_context *);
-static inline struct cfq_queue *cic_to_cfqq(struct cfq_io_context *cic,
- bool is_sync)
+static inline struct cfq_io_cq *icq_to_cic(struct io_cq *icq)
{
- return cic->cfqq[is_sync];
+ /* cic->icq is the first member, %NULL will convert to %NULL */
+ return container_of(icq, struct cfq_io_cq, icq);
}
-static inline void cic_set_cfqq(struct cfq_io_context *cic,
- struct cfq_queue *cfqq, bool is_sync)
+static inline struct cfq_io_cq *cfq_cic_lookup(struct cfq_data *cfqd,
+ struct io_context *ioc)
{
- cic->cfqq[is_sync] = cfqq;
+ if (ioc)
+ return icq_to_cic(ioc_lookup_icq(ioc, cfqd->queue));
+ return NULL;
}
-#define CIC_DEAD_KEY 1ul
-#define CIC_DEAD_INDEX_SHIFT 1
-
-static inline void *cfqd_dead_key(struct cfq_data *cfqd)
+static inline struct cfq_queue *cic_to_cfqq(struct cfq_io_cq *cic, bool is_sync)
{
- return (void *)(cfqd->cic_index << CIC_DEAD_INDEX_SHIFT | CIC_DEAD_KEY);
+ return cic->cfqq[is_sync];
}
-static inline struct cfq_data *cic_to_cfqd(struct cfq_io_context *cic)
+static inline void cic_set_cfqq(struct cfq_io_cq *cic, struct cfq_queue *cfqq,
+ bool is_sync)
{
- struct cfq_data *cfqd = cic->key;
-
- if (unlikely((unsigned long) cfqd & CIC_DEAD_KEY))
- return NULL;
+ cic->cfqq[is_sync] = cfqq;
+}
- return cfqd;
+static inline struct cfq_data *cic_to_cfqd(struct cfq_io_cq *cic)
+{
+ return cic->icq.q->elevator->elevator_data;
}
/*
@@ -1561,7 +1562,7 @@ static struct request *
cfq_find_rq_fmerge(struct cfq_data *cfqd, struct bio *bio)
{
struct task_struct *tsk = current;
- struct cfq_io_context *cic;
+ struct cfq_io_cq *cic;
struct cfq_queue *cfqq;
cic = cfq_cic_lookup(cfqd, tsk->io_context);
@@ -1687,7 +1688,7 @@ static int cfq_allow_merge(struct request_queue *q, struct request *rq,
struct bio *bio)
{
struct cfq_data *cfqd = q->elevator->elevator_data;
- struct cfq_io_context *cic;
+ struct cfq_io_cq *cic;
struct cfq_queue *cfqq;
/*
@@ -1697,12 +1698,19 @@ static int cfq_allow_merge(struct request_queue *q, struct request *rq,
return false;
/*
- * Lookup the cfqq that this bio will be queued with. Allow
- * merge only if rq is queued there.
+ * Lookup the cfqq that this bio will be queued with and allow
+ * merge only if rq is queued there. This function can be called
+ * from plug merge without queue_lock. In such cases, ioc of @rq
+ * and %current are guaranteed to be equal. Avoid lookup which
+ * requires queue_lock by using @rq's cic.
*/
- cic = cfq_cic_lookup(cfqd, current->io_context);
- if (!cic)
- return false;
+ if (current->io_context == RQ_CIC(rq)->icq.ioc) {
+ cic = RQ_CIC(rq);
+ } else {
+ cic = cfq_cic_lookup(cfqd, current->io_context);
+ if (!cic)
+ return false;
+ }
cfqq = cic_to_cfqq(cic, cfq_bio_sync(bio));
return cfqq == RQ_CFQQ(rq);
@@ -1786,7 +1794,7 @@ __cfq_slice_expired(struct cfq_data *cfqd, struct cfq_queue *cfqq,
cfqd->active_queue = NULL;
if (cfqd->active_cic) {
- put_io_context(cfqd->active_cic->ioc);
+ put_io_context(cfqd->active_cic->icq.ioc, cfqd->queue);
cfqd->active_cic = NULL;
}
}
@@ -2006,7 +2014,7 @@ static bool cfq_should_idle(struct cfq_data *cfqd, struct cfq_queue *cfqq)
static void cfq_arm_slice_timer(struct cfq_data *cfqd)
{
struct cfq_queue *cfqq = cfqd->active_queue;
- struct cfq_io_context *cic;
+ struct cfq_io_cq *cic;
unsigned long sl, group_idle = 0;
/*
@@ -2041,7 +2049,7 @@ static void cfq_arm_slice_timer(struct cfq_data *cfqd)
* task has exited, don't wait
*/
cic = cfqd->active_cic;
- if (!cic || !atomic_read(&cic->ioc->nr_tasks))
+ if (!cic || !atomic_read(&cic->icq.ioc->nr_tasks))
return;
/*
@@ -2592,9 +2600,9 @@ static bool cfq_dispatch_request(struct cfq_data *cfqd, struct cfq_queue *cfqq)
cfq_dispatch_insert(cfqd->queue, rq);
if (!cfqd->active_cic) {
- struct cfq_io_context *cic = RQ_CIC(rq);
+ struct cfq_io_cq *cic = RQ_CIC(rq);
- atomic_long_inc(&cic->ioc->refcount);
+ atomic_long_inc(&cic->icq.ioc->refcount);
cfqd->active_cic = cic;
}
@@ -2677,84 +2685,6 @@ static void cfq_put_queue(struct cfq_queue *cfqq)
cfq_put_cfqg(cfqg);
}
-/*
- * Call func for each cic attached to this ioc.
- */
-static void
-call_for_each_cic(struct io_context *ioc,
- void (*func)(struct io_context *, struct cfq_io_context *))
-{
- struct cfq_io_context *cic;
- struct hlist_node *n;
-
- rcu_read_lock();
-
- hlist_for_each_entry_rcu(cic, n, &ioc->cic_list, cic_list)
- func(ioc, cic);
-
- rcu_read_unlock();
-}
-
-static void cfq_cic_free_rcu(struct rcu_head *head)
-{
- struct cfq_io_context *cic;
-
- cic = container_of(head, struct cfq_io_context, rcu_head);
-
- kmem_cache_free(cfq_ioc_pool, cic);
- elv_ioc_count_dec(cfq_ioc_count);
-
- if (ioc_gone) {
- /*
- * CFQ scheduler is exiting, grab exit lock and check
- * the pending io context count. If it hits zero,
- * complete ioc_gone and set it back to NULL
- */
- spin_lock(&ioc_gone_lock);
- if (ioc_gone && !elv_ioc_count_read(cfq_ioc_count)) {
- complete(ioc_gone);
- ioc_gone = NULL;
- }
- spin_unlock(&ioc_gone_lock);
- }
-}
-
-static void cfq_cic_free(struct cfq_io_context *cic)
-{
- call_rcu(&cic->rcu_head, cfq_cic_free_rcu);
-}
-
-static void cic_free_func(struct io_context *ioc, struct cfq_io_context *cic)
-{
- unsigned long flags;
- unsigned long dead_key = (unsigned long) cic->key;
-
- BUG_ON(!(dead_key & CIC_DEAD_KEY));
-
- spin_lock_irqsave(&ioc->lock, flags);
- radix_tree_delete(&ioc->radix_root, dead_key >> CIC_DEAD_INDEX_SHIFT);
- hlist_del_rcu(&cic->cic_list);
- spin_unlock_irqrestore(&ioc->lock, flags);
-
- cfq_cic_free(cic);
-}
-
-/*
- * Must be called with rcu_read_lock() held or preemption otherwise disabled.
- * Only two callers of this - ->dtor() which is called with the rcu_read_lock(),
- * and ->trim() which is called with the task lock held
- */
-static void cfq_free_io_context(struct io_context *ioc)
-{
- /*
- * ioc->refcount is zero here, or we are called from elv_unregister(),
- * so no more cic's are allowed to be linked into this ioc. So it
- * should be ok to iterate over the known list, we will see all cic's
- * since no new ones are added.
- */
- call_for_each_cic(ioc, cic_free_func);
-}
-
static void cfq_put_cooperator(struct cfq_queue *cfqq)
{
struct cfq_queue *__cfqq, *next;
@@ -2788,27 +2718,17 @@ static void cfq_exit_cfqq(struct cfq_data *cfqd, struct cfq_queue *cfqq)
cfq_put_queue(cfqq);
}
-static void __cfq_exit_single_io_context(struct cfq_data *cfqd,
- struct cfq_io_context *cic)
+static void cfq_init_icq(struct io_cq *icq)
{
- struct io_context *ioc = cic->ioc;
+ struct cfq_io_cq *cic = icq_to_cic(icq);
- list_del_init(&cic->queue_list);
-
- /*
- * Make sure dead mark is seen for dead queues
- */
- smp_wmb();
- cic->key = cfqd_dead_key(cfqd);
+ cic->ttime.last_end_request = jiffies;
+}
- rcu_read_lock();
- if (rcu_dereference(ioc->ioc_data) == cic) {
- rcu_read_unlock();
- spin_lock(&ioc->lock);
- rcu_assign_pointer(ioc->ioc_data, NULL);
- spin_unlock(&ioc->lock);
- } else
- rcu_read_unlock();
+static void cfq_exit_icq(struct io_cq *icq)
+{
+ struct cfq_io_cq *cic = icq_to_cic(icq);
+ struct cfq_data *cfqd = cic_to_cfqd(cic);
if (cic->cfqq[BLK_RW_ASYNC]) {
cfq_exit_cfqq(cfqd, cic->cfqq[BLK_RW_ASYNC]);
@@ -2821,57 +2741,6 @@ static void __cfq_exit_single_io_context(struct cfq_data *cfqd,
}
}
-static void cfq_exit_single_io_context(struct io_context *ioc,
- struct cfq_io_context *cic)
-{
- struct cfq_data *cfqd = cic_to_cfqd(cic);
-
- if (cfqd) {
- struct request_queue *q = cfqd->queue;
- unsigned long flags;
-
- spin_lock_irqsave(q->queue_lock, flags);
-
- /*
- * Ensure we get a fresh copy of the ->key to prevent
- * race between exiting task and queue
- */
- smp_read_barrier_depends();
- if (cic->key == cfqd)
- __cfq_exit_single_io_context(cfqd, cic);
-
- spin_unlock_irqrestore(q->queue_lock, flags);
- }
-}
-
-/*
- * 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)
-{
- call_for_each_cic(ioc, cfq_exit_single_io_context);
-}
-
-static struct cfq_io_context *
-cfq_alloc_io_context(struct cfq_data *cfqd, gfp_t gfp_mask)
-{
- struct cfq_io_context *cic;
-
- cic = kmem_cache_alloc_node(cfq_ioc_pool, gfp_mask | __GFP_ZERO,
- cfqd->queue->node);
- if (cic) {
- cic->ttime.last_end_request = jiffies;
- INIT_LIST_HEAD(&cic->queue_list);
- INIT_HLIST_NODE(&cic->cic_list);
- cic->dtor = cfq_free_io_context;
- cic->exit = cfq_exit_io_context;
- elv_ioc_count_inc(cfq_ioc_count);
- }
-
- return cic;
-}
-
static void cfq_init_prio_data(struct cfq_queue *cfqq, struct io_context *ioc)
{
struct task_struct *tsk = current;
@@ -2914,21 +2783,18 @@ static void cfq_init_prio_data(struct cfq_queue *cfqq, struct io_context *ioc)
cfq_clear_cfqq_prio_changed(cfqq);
}
-static void changed_ioprio(struct io_context *ioc, struct cfq_io_context *cic)
+static void changed_ioprio(struct cfq_io_cq *cic)
{
struct cfq_data *cfqd = cic_to_cfqd(cic);
struct cfq_queue *cfqq;
- unsigned long flags;
if (unlikely(!cfqd))
return;
- spin_lock_irqsave(cfqd->queue->queue_lock, flags);
-
cfqq = cic->cfqq[BLK_RW_ASYNC];
if (cfqq) {
struct cfq_queue *new_cfqq;
- new_cfqq = cfq_get_queue(cfqd, BLK_RW_ASYNC, cic->ioc,
+ new_cfqq = cfq_get_queue(cfqd, BLK_RW_ASYNC, cic->icq.ioc,
GFP_ATOMIC);
if (new_cfqq) {
cic->cfqq[BLK_RW_ASYNC] = new_cfqq;
@@ -2939,14 +2805,6 @@ static void changed_ioprio(struct io_context *ioc, struct cfq_io_context *cic)
cfqq = cic->cfqq[BLK_RW_SYNC];
if (cfqq)
cfq_mark_cfqq_prio_changed(cfqq);
-
- spin_unlock_irqrestore(cfqd->queue->queue_lock, flags);
-}
-
-static void cfq_ioc_set_ioprio(struct io_context *ioc)
-{
- call_for_each_cic(ioc, changed_ioprio);
- ioc->ioprio_changed = 0;
}
static void cfq_init_cfqq(struct cfq_data *cfqd, struct cfq_queue *cfqq,
@@ -2970,11 +2828,10 @@ static void cfq_init_cfqq(struct cfq_data *cfqd, struct cfq_queue *cfqq,
}
#ifdef CONFIG_CFQ_GROUP_IOSCHED
-static void changed_cgroup(struct io_context *ioc, struct cfq_io_context *cic)
+static void changed_cgroup(struct cfq_io_cq *cic)
{
struct cfq_queue *sync_cfqq = cic_to_cfqq(cic, 1);
struct cfq_data *cfqd = cic_to_cfqd(cic);
- unsigned long flags;
struct request_queue *q;
if (unlikely(!cfqd))
@@ -2982,8 +2839,6 @@ static void changed_cgroup(struct io_context *ioc, struct cfq_io_context *cic)
q = cfqd->queue;
- spin_lock_irqsave(q->queue_lock, flags);
-
if (sync_cfqq) {
/*
* Drop reference to sync queue. A new sync queue will be
@@ -2993,14 +2848,6 @@ static void changed_cgroup(struct io_context *ioc, struct cfq_io_context *cic)
cic_set_cfqq(cic, NULL, 1);
cfq_put_queue(sync_cfqq);
}
-
- spin_unlock_irqrestore(q->queue_lock, flags);
-}
-
-static void cfq_ioc_set_cgroup(struct io_context *ioc)
-{
- call_for_each_cic(ioc, changed_cgroup);
- ioc->cgroup_changed = 0;
}
#endif /* CONFIG_CFQ_GROUP_IOSCHED */
@@ -3009,7 +2856,7 @@ cfq_find_alloc_queue(struct cfq_data *cfqd, bool is_sync,
struct io_context *ioc, gfp_t gfp_mask)
{
struct cfq_queue *cfqq, *new_cfqq = NULL;
- struct cfq_io_context *cic;
+ struct cfq_io_cq *cic;
struct cfq_group *cfqg;
retry:
@@ -3100,160 +2947,6 @@ cfq_get_queue(struct cfq_data *cfqd, bool is_sync, struct io_context *ioc,
return cfqq;
}
-/*
- * We drop cfq io contexts lazily, so we may find a dead one.
- */
-static void
-cfq_drop_dead_cic(struct cfq_data *cfqd, struct io_context *ioc,
- struct cfq_io_context *cic)
-{
- unsigned long flags;
-
- WARN_ON(!list_empty(&cic->queue_list));
- BUG_ON(cic->key != cfqd_dead_key(cfqd));
-
- spin_lock_irqsave(&ioc->lock, flags);
-
- BUG_ON(rcu_dereference_check(ioc->ioc_data,
- lockdep_is_held(&ioc->lock)) == cic);
-
- radix_tree_delete(&ioc->radix_root, cfqd->cic_index);
- hlist_del_rcu(&cic->cic_list);
- spin_unlock_irqrestore(&ioc->lock, flags);
-
- cfq_cic_free(cic);
-}
-
-static struct cfq_io_context *
-cfq_cic_lookup(struct cfq_data *cfqd, struct io_context *ioc)
-{
- struct cfq_io_context *cic;
- unsigned long flags;
-
- if (unlikely(!ioc))
- return NULL;
-
- rcu_read_lock();
-
- /*
- * we maintain a last-hit cache, to avoid browsing over the tree
- */
- cic = rcu_dereference(ioc->ioc_data);
- if (cic && cic->key == cfqd) {
- rcu_read_unlock();
- return cic;
- }
-
- do {
- cic = radix_tree_lookup(&ioc->radix_root, cfqd->cic_index);
- rcu_read_unlock();
- if (!cic)
- break;
- if (unlikely(cic->key != cfqd)) {
- cfq_drop_dead_cic(cfqd, ioc, cic);
- rcu_read_lock();
- continue;
- }
-
- spin_lock_irqsave(&ioc->lock, flags);
- rcu_assign_pointer(ioc->ioc_data, cic);
- spin_unlock_irqrestore(&ioc->lock, flags);
- break;
- } while (1);
-
- return cic;
-}
-
-/*
- * Add cic into ioc, using cfqd as the search key. This enables us to lookup
- * the process specific cfq io context when entered from the block layer.
- * Also adds the cic to a per-cfqd list, used when this queue is removed.
- */
-static int cfq_cic_link(struct cfq_data *cfqd, struct io_context *ioc,
- struct cfq_io_context *cic, gfp_t gfp_mask)
-{
- unsigned long flags;
- int ret;
-
- ret = radix_tree_preload(gfp_mask);
- if (!ret) {
- cic->ioc = ioc;
- cic->key = cfqd;
-
- spin_lock_irqsave(&ioc->lock, flags);
- ret = radix_tree_insert(&ioc->radix_root,
- cfqd->cic_index, cic);
- if (!ret)
- hlist_add_head_rcu(&cic->cic_list, &ioc->cic_list);
- spin_unlock_irqrestore(&ioc->lock, flags);
-
- radix_tree_preload_end();
-
- if (!ret) {
- spin_lock_irqsave(cfqd->queue->queue_lock, flags);
- list_add(&cic->queue_list, &cfqd->cic_list);
- spin_unlock_irqrestore(cfqd->queue->queue_lock, flags);
- }
- }
-
- if (ret && ret != -EEXIST)
- printk(KERN_ERR "cfq: cic link failed!\n");
-
- return ret;
-}
-
-/*
- * Setup general io context and cfq io context. There can be several cfq
- * io contexts per general io context, if this process is doing io to more
- * than one device managed by cfq.
- */
-static struct cfq_io_context *
-cfq_get_io_context(struct cfq_data *cfqd, gfp_t gfp_mask)
-{
- struct io_context *ioc = NULL;
- struct cfq_io_context *cic;
- int ret;
-
- might_sleep_if(gfp_mask & __GFP_WAIT);
-
- ioc = get_io_context(gfp_mask, cfqd->queue->node);
- if (!ioc)
- return NULL;
-
-retry:
- cic = cfq_cic_lookup(cfqd, ioc);
- if (cic)
- goto out;
-
- cic = cfq_alloc_io_context(cfqd, gfp_mask);
- if (cic == NULL)
- goto err;
-
- ret = cfq_cic_link(cfqd, ioc, cic, gfp_mask);
- if (ret == -EEXIST) {
- /* someone has linked cic to ioc already */
- cfq_cic_free(cic);
- goto retry;
- } else if (ret)
- goto err_free;
-
-out:
- smp_read_barrier_depends();
- if (unlikely(ioc->ioprio_changed))
- cfq_ioc_set_ioprio(ioc);
-
-#ifdef CONFIG_CFQ_GROUP_IOSCHED
- if (unlikely(ioc->cgroup_changed))
- cfq_ioc_set_cgroup(ioc);
-#endif
- return cic;
-err_free:
- cfq_cic_free(cic);
-err:
- put_io_context(ioc);
- return NULL;
-}
-
static void
__cfq_update_io_thinktime(struct cfq_ttime *ttime, unsigned long slice_idle)
{
@@ -3267,7 +2960,7 @@ __cfq_update_io_thinktime(struct cfq_ttime *ttime, unsigned long slice_idle)
static void
cfq_update_io_thinktime(struct cfq_data *cfqd, struct cfq_queue *cfqq,
- struct cfq_io_context *cic)
+ struct cfq_io_cq *cic)
{
if (cfq_cfqq_sync(cfqq)) {
__cfq_update_io_thinktime(&cic->ttime, cfqd->cfq_slice_idle);
@@ -3305,7 +2998,7 @@ cfq_update_io_seektime(struct cfq_data *cfqd, struct cfq_queue *cfqq,
*/
static void
cfq_update_idle_window(struct cfq_data *cfqd, struct cfq_queue *cfqq,
- struct cfq_io_context *cic)
+ struct cfq_io_cq *cic)
{
int old_idle, enable_idle;
@@ -3322,8 +3015,9 @@ cfq_update_idle_window(struct cfq_data *cfqd, struct cfq_queue *cfqq,
if (cfqq->next_rq && (cfqq->next_rq->cmd_flags & REQ_NOIDLE))
enable_idle = 0;
- else if (!atomic_read(&cic->ioc->nr_tasks) || !cfqd->cfq_slice_idle ||
- (!cfq_cfqq_deep(cfqq) && CFQQ_SEEKY(cfqq)))
+ else if (!atomic_read(&cic->icq.ioc->nr_tasks) ||
+ !cfqd->cfq_slice_idle ||
+ (!cfq_cfqq_deep(cfqq) && CFQQ_SEEKY(cfqq)))
enable_idle = 0;
else if (sample_valid(cic->ttime.ttime_samples)) {
if (cic->ttime.ttime_mean > cfqd->cfq_slice_idle)
@@ -3423,18 +3117,17 @@ cfq_should_preempt(struct cfq_data *cfqd, struct cfq_queue *new_cfqq,
*/
static void cfq_preempt_queue(struct cfq_data *cfqd, struct cfq_queue *cfqq)
{
- struct cfq_queue *old_cfqq = cfqd->active_queue;
-
cfq_log_cfqq(cfqd, cfqq, "preempt");
- cfq_slice_expired(cfqd, 1);
/*
* workload type is changed, don't save slice, otherwise preempt
* doesn't happen
*/
- if (cfqq_type(old_cfqq) != cfqq_type(cfqq))
+ if (cfqq_type(cfqd->active_queue) != cfqq_type(cfqq))
cfqq->cfqg->saved_workload_slice = 0;
+ 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.
@@ -3455,7 +3148,7 @@ static void
cfq_rq_enqueued(struct cfq_data *cfqd, struct cfq_queue *cfqq,
struct request *rq)
{
- struct cfq_io_context *cic = RQ_CIC(rq);
+ struct cfq_io_cq *cic = RQ_CIC(rq);
cfqd->rq_queued++;
if (rq->cmd_flags & REQ_PRIO)
@@ -3508,7 +3201,7 @@ static void cfq_insert_request(struct request_queue *q, struct request *rq)
struct cfq_queue *cfqq = RQ_CFQQ(rq);
cfq_log_cfqq(cfqd, cfqq, "insert_request");
- cfq_init_prio_data(cfqq, RQ_CIC(rq)->ioc);
+ cfq_init_prio_data(cfqq, RQ_CIC(rq)->icq.ioc);
rq_set_fifo_time(rq, jiffies + cfqd->cfq_fifo_expire[rq_is_sync(rq)]);
list_add_tail(&rq->queuelist, &cfqq->fifo);
@@ -3558,7 +3251,7 @@ static void cfq_update_hw_tag(struct cfq_data *cfqd)
static bool cfq_should_wait_busy(struct cfq_data *cfqd, struct cfq_queue *cfqq)
{
- struct cfq_io_context *cic = cfqd->active_cic;
+ struct cfq_io_cq *cic = cfqd->active_cic;
/* If the queue already has requests, don't wait */
if (!RB_EMPTY_ROOT(&cfqq->sort_list))
@@ -3695,7 +3388,7 @@ static int cfq_may_queue(struct request_queue *q, int rw)
{
struct cfq_data *cfqd = q->elevator->elevator_data;
struct task_struct *tsk = current;
- struct cfq_io_context *cic;
+ struct cfq_io_cq *cic;
struct cfq_queue *cfqq;
/*
@@ -3710,7 +3403,7 @@ static int cfq_may_queue(struct request_queue *q, int rw)
cfqq = cic_to_cfqq(cic, rw_is_sync(rw));
if (cfqq) {
- cfq_init_prio_data(cfqq, cic->ioc);
+ cfq_init_prio_data(cfqq, cic->icq.ioc);
return __cfq_may_queue(cfqq);
}
@@ -3731,21 +3424,17 @@ static void cfq_put_request(struct request *rq)
BUG_ON(!cfqq->allocated[rw]);
cfqq->allocated[rw]--;
- put_io_context(RQ_CIC(rq)->ioc);
-
- rq->elevator_private[0] = NULL;
- rq->elevator_private[1] = NULL;
-
/* Put down rq reference on cfqg */
cfq_put_cfqg(RQ_CFQG(rq));
- rq->elevator_private[2] = NULL;
+ rq->elv.priv[0] = NULL;
+ rq->elv.priv[1] = NULL;
cfq_put_queue(cfqq);
}
}
static struct cfq_queue *
-cfq_merge_cfqqs(struct cfq_data *cfqd, struct cfq_io_context *cic,
+cfq_merge_cfqqs(struct cfq_data *cfqd, struct cfq_io_cq *cic,
struct cfq_queue *cfqq)
{
cfq_log_cfqq(cfqd, cfqq, "merging with queue %p", cfqq->new_cfqq);
@@ -3760,7 +3449,7 @@ cfq_merge_cfqqs(struct cfq_data *cfqd, struct cfq_io_context *cic,
* was the last process referring to said cfqq.
*/
static struct cfq_queue *
-split_cfqq(struct cfq_io_context *cic, struct cfq_queue *cfqq)
+split_cfqq(struct cfq_io_cq *cic, struct cfq_queue *cfqq)
{
if (cfqq_process_refs(cfqq) == 1) {
cfqq->pid = current->pid;
@@ -3783,25 +3472,29 @@ static int
cfq_set_request(struct request_queue *q, struct request *rq, gfp_t gfp_mask)
{
struct cfq_data *cfqd = q->elevator->elevator_data;
- struct cfq_io_context *cic;
+ struct cfq_io_cq *cic = icq_to_cic(rq->elv.icq);
const int rw = rq_data_dir(rq);
const bool is_sync = rq_is_sync(rq);
struct cfq_queue *cfqq;
- unsigned long flags;
might_sleep_if(gfp_mask & __GFP_WAIT);
- cic = cfq_get_io_context(cfqd, gfp_mask);
-
- spin_lock_irqsave(q->queue_lock, flags);
+ spin_lock_irq(q->queue_lock);
- if (!cic)
- goto queue_fail;
+ /* handle changed notifications */
+ if (unlikely(cic->icq.changed)) {
+ if (test_and_clear_bit(ICQ_IOPRIO_CHANGED, &cic->icq.changed))
+ changed_ioprio(cic);
+#ifdef CONFIG_CFQ_GROUP_IOSCHED
+ if (test_and_clear_bit(ICQ_CGROUP_CHANGED, &cic->icq.changed))
+ changed_cgroup(cic);
+#endif
+ }
new_queue:
cfqq = cic_to_cfqq(cic, is_sync);
if (!cfqq || cfqq == &cfqd->oom_cfqq) {
- cfqq = cfq_get_queue(cfqd, is_sync, cic->ioc, gfp_mask);
+ cfqq = cfq_get_queue(cfqd, is_sync, cic->icq.ioc, gfp_mask);
cic_set_cfqq(cic, cfqq, is_sync);
} else {
/*
@@ -3827,17 +3520,10 @@ new_queue:
cfqq->allocated[rw]++;
cfqq->ref++;
- rq->elevator_private[0] = cic;
- rq->elevator_private[1] = cfqq;
- rq->elevator_private[2] = cfq_ref_get_cfqg(cfqq->cfqg);
- spin_unlock_irqrestore(q->queue_lock, flags);
+ rq->elv.priv[0] = cfqq;
+ rq->elv.priv[1] = cfq_ref_get_cfqg(cfqq->cfqg);
+ spin_unlock_irq(q->queue_lock);
return 0;
-
-queue_fail:
- cfq_schedule_dispatch(cfqd);
- spin_unlock_irqrestore(q->queue_lock, flags);
- cfq_log(cfqd, "set_request fail");
- return 1;
}
static void cfq_kick_queue(struct work_struct *work)
@@ -3941,14 +3627,6 @@ static void cfq_exit_queue(struct elevator_queue *e)
if (cfqd->active_queue)
__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,
- struct cfq_io_context,
- queue_list);
-
- __cfq_exit_single_io_context(cfqd, cic);
- }
-
cfq_put_async_queues(cfqd);
cfq_release_cfq_groups(cfqd);
@@ -3963,10 +3641,6 @@ static void cfq_exit_queue(struct elevator_queue *e)
cfq_shutdown_timer_wq(cfqd);
- spin_lock(&cic_index_lock);
- ida_remove(&cic_index_ida, cfqd->cic_index);
- spin_unlock(&cic_index_lock);
-
/*
* Wait for cfqg->blkg->key accessors to exit their grace periods.
* Do this wait only if there are other unlinked groups out
@@ -3988,24 +3662,6 @@ static void cfq_exit_queue(struct elevator_queue *e)
kfree(cfqd);
}
-static int cfq_alloc_cic_index(void)
-{
- int index, error;
-
- do {
- if (!ida_pre_get(&cic_index_ida, GFP_KERNEL))
- return -ENOMEM;
-
- spin_lock(&cic_index_lock);
- error = ida_get_new(&cic_index_ida, &index);
- spin_unlock(&cic_index_lock);
- if (error && error != -EAGAIN)
- return error;
- } while (error);
-
- return index;
-}
-
static void *cfq_init_queue(struct request_queue *q)
{
struct cfq_data *cfqd;
@@ -4013,23 +3669,9 @@ static void *cfq_init_queue(struct request_queue *q)
struct cfq_group *cfqg;
struct cfq_rb_root *st;
- i = cfq_alloc_cic_index();
- if (i < 0)
- return NULL;
-
cfqd = kmalloc_node(sizeof(*cfqd), GFP_KERNEL | __GFP_ZERO, q->node);
- if (!cfqd) {
- spin_lock(&cic_index_lock);
- ida_remove(&cic_index_ida, i);
- spin_unlock(&cic_index_lock);
+ if (!cfqd)
return NULL;
- }
-
- /*
- * Don't need take queue_lock in the routine, since we are
- * initializing the ioscheduler, and nobody is using cfqd
- */
- cfqd->cic_index = i;
/* Init root service tree */
cfqd->grp_service_tree = CFQ_RB_ROOT;
@@ -4055,11 +3697,6 @@ static void *cfq_init_queue(struct request_queue *q)
if (blkio_alloc_blkg_stats(&cfqg->blkg)) {
kfree(cfqg);
-
- spin_lock(&cic_index_lock);
- ida_remove(&cic_index_ida, cfqd->cic_index);
- spin_unlock(&cic_index_lock);
-
kfree(cfqd);
return NULL;
}
@@ -4091,8 +3728,6 @@ static void *cfq_init_queue(struct request_queue *q)
cfqd->oom_cfqq.ref++;
cfq_link_cfqq_cfqg(&cfqd->oom_cfqq, &cfqd->root_group);
- INIT_LIST_HEAD(&cfqd->cic_list);
-
cfqd->queue = q;
init_timer(&cfqd->idle_slice_timer);
@@ -4121,34 +3756,6 @@ static void *cfq_init_queue(struct request_queue *q)
return cfqd;
}
-static void cfq_slab_kill(void)
-{
- /*
- * Caller already ensured that pending RCU callbacks are completed,
- * so we should have no busy allocations at this point.
- */
- if (cfq_pool)
- kmem_cache_destroy(cfq_pool);
- if (cfq_ioc_pool)
- kmem_cache_destroy(cfq_ioc_pool);
-}
-
-static int __init cfq_slab_setup(void)
-{
- cfq_pool = KMEM_CACHE(cfq_queue, 0);
- if (!cfq_pool)
- goto fail;
-
- cfq_ioc_pool = KMEM_CACHE(cfq_io_context, 0);
- if (!cfq_ioc_pool)
- goto fail;
-
- return 0;
-fail:
- cfq_slab_kill();
- return -ENOMEM;
-}
-
/*
* sysfs parts below -->
*/
@@ -4254,15 +3861,18 @@ static struct elevator_type iosched_cfq = {
.elevator_completed_req_fn = cfq_completed_request,
.elevator_former_req_fn = elv_rb_former_request,
.elevator_latter_req_fn = elv_rb_latter_request,
+ .elevator_init_icq_fn = cfq_init_icq,
+ .elevator_exit_icq_fn = cfq_exit_icq,
.elevator_set_req_fn = cfq_set_request,
.elevator_put_req_fn = cfq_put_request,
.elevator_may_queue_fn = cfq_may_queue,
.elevator_init_fn = cfq_init_queue,
.elevator_exit_fn = cfq_exit_queue,
- .trim = cfq_free_io_context,
},
+ .icq_size = sizeof(struct cfq_io_cq),
+ .icq_align = __alignof__(struct cfq_io_cq),
.elevator_attrs = cfq_attrs,
- .elevator_name = "cfq",
+ .elevator_name = "cfq",
.elevator_owner = THIS_MODULE,
};
@@ -4280,6 +3890,8 @@ static struct blkio_policy_type blkio_policy_cfq;
static int __init cfq_init(void)
{
+ int ret;
+
/*
* could be 0 on HZ < 1000 setups
*/
@@ -4294,10 +3906,16 @@ static int __init cfq_init(void)
#else
cfq_group_idle = 0;
#endif
- if (cfq_slab_setup())
+ cfq_pool = KMEM_CACHE(cfq_queue, 0);
+ if (!cfq_pool)
return -ENOMEM;
- elv_register(&iosched_cfq);
+ ret = elv_register(&iosched_cfq);
+ if (ret) {
+ kmem_cache_destroy(cfq_pool);
+ return ret;
+ }
+
blkio_policy_register(&blkio_policy_cfq);
return 0;
@@ -4305,21 +3923,9 @@ static int __init cfq_init(void)
static void __exit cfq_exit(void)
{
- DECLARE_COMPLETION_ONSTACK(all_gone);
blkio_policy_unregister(&blkio_policy_cfq);
elv_unregister(&iosched_cfq);
- ioc_gone = &all_gone;
- /* ioc_gone's update must be visible before reading ioc_count */
- smp_wmb();
-
- /*
- * this also protects us from entering cfq_slab_kill() with
- * pending RCU callbacks
- */
- if (elv_ioc_count_read(cfq_ioc_count))
- wait_for_completion(&all_gone);
- ida_destroy(&cic_index_ida);
- cfq_slab_kill();
+ kmem_cache_destroy(cfq_pool);
}
module_init(cfq_init);