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-rw-r--r--block/cfq-iosched.c182
1 files changed, 143 insertions, 39 deletions
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index 5f127cfb2e92..5ff4f4850e71 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -55,6 +55,7 @@ static const int cfq_hist_divisor = 4;
#define RQ_CIC(rq) \
((struct cfq_io_context *) (rq)->elevator_private)
#define RQ_CFQQ(rq) (struct cfq_queue *) ((rq)->elevator_private2)
+#define RQ_CFQG(rq) (struct cfq_group *) ((rq)->elevator_private3)
static struct kmem_cache *cfq_pool;
static struct kmem_cache *cfq_ioc_pool;
@@ -63,6 +64,9 @@ 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)
#define cfq_class_rt(cfqq) ((cfqq)->ioprio_class == IOPRIO_CLASS_RT)
@@ -143,8 +147,6 @@ struct cfq_queue {
struct cfq_queue *new_cfqq;
struct cfq_group *cfqg;
struct cfq_group *orig_cfqg;
- /* Sectors dispatched in current dispatch round */
- unsigned long nr_sectors;
};
/*
@@ -272,6 +274,7 @@ struct cfq_data {
unsigned int cfq_latency;
unsigned int cfq_group_isolation;
+ unsigned int cic_index;
struct list_head cic_list;
/*
@@ -346,7 +349,7 @@ CFQ_CFQQ_FNS(deep);
CFQ_CFQQ_FNS(wait_busy);
#undef CFQ_CFQQ_FNS
-#ifdef CONFIG_DEBUG_CFQ_IOSCHED
+#ifdef CONFIG_CFQ_GROUP_IOSCHED
#define cfq_log_cfqq(cfqd, cfqq, fmt, args...) \
blk_add_trace_msg((cfqd)->queue, "cfq%d%c %s " fmt, (cfqq)->pid, \
cfq_cfqq_sync((cfqq)) ? 'S' : 'A', \
@@ -431,6 +434,24 @@ static inline void cic_set_cfqq(struct cfq_io_context *cic,
cic->cfqq[is_sync] = cfqq;
}
+#define CIC_DEAD_KEY 1ul
+#define CIC_DEAD_INDEX_SHIFT 1
+
+static inline void *cfqd_dead_key(struct cfq_data *cfqd)
+{
+ return (void *)(cfqd->cic_index << CIC_DEAD_INDEX_SHIFT | CIC_DEAD_KEY);
+}
+
+static inline struct cfq_data *cic_to_cfqd(struct cfq_io_context *cic)
+{
+ struct cfq_data *cfqd = cic->key;
+
+ if (unlikely((unsigned long) cfqd & CIC_DEAD_KEY))
+ return NULL;
+
+ return cfqd;
+}
+
/*
* We regard a request as SYNC, if it's either a read or has the SYNC bit
* set (in which case it could also be direct WRITE).
@@ -858,7 +879,7 @@ cfq_group_service_tree_del(struct cfq_data *cfqd, struct cfq_group *cfqg)
if (!RB_EMPTY_NODE(&cfqg->rb_node))
cfq_rb_erase(&cfqg->rb_node, st);
cfqg->saved_workload_slice = 0;
- blkiocg_update_blkio_group_dequeue_stats(&cfqg->blkg, 1);
+ blkiocg_update_dequeue_stats(&cfqg->blkg, 1);
}
static inline unsigned int cfq_cfqq_slice_usage(struct cfq_queue *cfqq)
@@ -884,8 +905,7 @@ static inline unsigned int cfq_cfqq_slice_usage(struct cfq_queue *cfqq)
slice_used = cfqq->allocated_slice;
}
- cfq_log_cfqq(cfqq->cfqd, cfqq, "sl_used=%u sect=%lu", slice_used,
- cfqq->nr_sectors);
+ cfq_log_cfqq(cfqq->cfqd, cfqq, "sl_used=%u", slice_used);
return slice_used;
}
@@ -919,8 +939,8 @@ static void cfq_group_served(struct cfq_data *cfqd, struct cfq_group *cfqg,
cfq_log_cfqg(cfqd, cfqg, "served: vt=%llu min_vt=%llu", cfqg->vdisktime,
st->min_vdisktime);
- blkiocg_update_blkio_group_stats(&cfqg->blkg, used_sl,
- cfqq->nr_sectors);
+ blkiocg_update_timeslice_used(&cfqg->blkg, used_sl);
+ blkiocg_set_start_empty_time(&cfqg->blkg);
}
#ifdef CONFIG_CFQ_GROUP_IOSCHED
@@ -961,7 +981,6 @@ cfq_find_alloc_cfqg(struct cfq_data *cfqd, struct cgroup *cgroup, int create)
if (!cfqg)
goto done;
- cfqg->weight = blkcg->weight;
for_each_cfqg_st(cfqg, i, j, st)
*st = CFQ_RB_ROOT;
RB_CLEAR_NODE(&cfqg->rb_node);
@@ -978,6 +997,7 @@ cfq_find_alloc_cfqg(struct cfq_data *cfqd, struct cgroup *cgroup, int create)
sscanf(dev_name(bdi->dev), "%u:%u", &major, &minor);
blkiocg_add_blkio_group(blkcg, &cfqg->blkg, (void *)cfqd,
MKDEV(major, minor));
+ cfqg->weight = blkcg_get_weight(blkcg, cfqg->blkg.dev);
/* Add group on cfqd list */
hlist_add_head(&cfqg->cfqd_node, &cfqd->cfqg_list);
@@ -1004,6 +1024,12 @@ static struct cfq_group *cfq_get_cfqg(struct cfq_data *cfqd, int create)
return cfqg;
}
+static inline struct cfq_group *cfq_ref_get_cfqg(struct cfq_group *cfqg)
+{
+ atomic_inc(&cfqg->ref);
+ return cfqg;
+}
+
static void cfq_link_cfqq_cfqg(struct cfq_queue *cfqq, struct cfq_group *cfqg)
{
/* Currently, all async queues are mapped to root group */
@@ -1087,6 +1113,12 @@ static struct cfq_group *cfq_get_cfqg(struct cfq_data *cfqd, int create)
{
return &cfqd->root_group;
}
+
+static inline struct cfq_group *cfq_ref_get_cfqg(struct cfq_group *cfqg)
+{
+ return cfqg;
+}
+
static inline void
cfq_link_cfqq_cfqg(struct cfq_queue *cfqq, struct cfq_group *cfqg) {
cfqq->cfqg = cfqg;
@@ -1389,7 +1421,12 @@ static void cfq_reposition_rq_rb(struct cfq_queue *cfqq, struct request *rq)
{
elv_rb_del(&cfqq->sort_list, rq);
cfqq->queued[rq_is_sync(rq)]--;
+ blkiocg_update_io_remove_stats(&(RQ_CFQG(rq))->blkg, rq_data_dir(rq),
+ rq_is_sync(rq));
cfq_add_rq_rb(rq);
+ blkiocg_update_io_add_stats(&(RQ_CFQG(rq))->blkg,
+ &cfqq->cfqd->serving_group->blkg, rq_data_dir(rq),
+ rq_is_sync(rq));
}
static struct request *
@@ -1445,6 +1482,8 @@ static void cfq_remove_request(struct request *rq)
cfq_del_rq_rb(rq);
cfqq->cfqd->rq_queued--;
+ blkiocg_update_io_remove_stats(&(RQ_CFQG(rq))->blkg, rq_data_dir(rq),
+ rq_is_sync(rq));
if (rq_is_meta(rq)) {
WARN_ON(!cfqq->meta_pending);
cfqq->meta_pending--;
@@ -1476,6 +1515,13 @@ static void cfq_merged_request(struct request_queue *q, struct request *req,
}
}
+static void cfq_bio_merged(struct request_queue *q, struct request *req,
+ struct bio *bio)
+{
+ blkiocg_update_io_merged_stats(&(RQ_CFQG(req))->blkg, bio_data_dir(bio),
+ cfq_bio_sync(bio));
+}
+
static void
cfq_merged_requests(struct request_queue *q, struct request *rq,
struct request *next)
@@ -1493,6 +1539,8 @@ cfq_merged_requests(struct request_queue *q, struct request *rq,
if (cfqq->next_rq == next)
cfqq->next_rq = rq;
cfq_remove_request(next);
+ blkiocg_update_io_merged_stats(&(RQ_CFQG(rq))->blkg, rq_data_dir(next),
+ rq_is_sync(next));
}
static int cfq_allow_merge(struct request_queue *q, struct request *rq,
@@ -1520,18 +1568,24 @@ static int cfq_allow_merge(struct request_queue *q, struct request *rq,
return cfqq == RQ_CFQQ(rq);
}
+static inline void cfq_del_timer(struct cfq_data *cfqd, struct cfq_queue *cfqq)
+{
+ del_timer(&cfqd->idle_slice_timer);
+ blkiocg_update_idle_time_stats(&cfqq->cfqg->blkg);
+}
+
static void __cfq_set_active_queue(struct cfq_data *cfqd,
struct cfq_queue *cfqq)
{
if (cfqq) {
cfq_log_cfqq(cfqd, cfqq, "set_active wl_prio:%d wl_type:%d",
cfqd->serving_prio, cfqd->serving_type);
+ blkiocg_update_avg_queue_size_stats(&cfqq->cfqg->blkg);
cfqq->slice_start = 0;
cfqq->dispatch_start = jiffies;
cfqq->allocated_slice = 0;
cfqq->slice_end = 0;
cfqq->slice_dispatch = 0;
- cfqq->nr_sectors = 0;
cfq_clear_cfqq_wait_request(cfqq);
cfq_clear_cfqq_must_dispatch(cfqq);
@@ -1539,7 +1593,7 @@ static void __cfq_set_active_queue(struct cfq_data *cfqd,
cfq_clear_cfqq_fifo_expire(cfqq);
cfq_mark_cfqq_slice_new(cfqq);
- del_timer(&cfqd->idle_slice_timer);
+ cfq_del_timer(cfqd, cfqq);
}
cfqd->active_queue = cfqq;
@@ -1555,7 +1609,7 @@ __cfq_slice_expired(struct cfq_data *cfqd, struct cfq_queue *cfqq,
cfq_log_cfqq(cfqd, cfqq, "slice expired t=%d", timed_out);
if (cfq_cfqq_wait_request(cfqq))
- del_timer(&cfqd->idle_slice_timer);
+ cfq_del_timer(cfqd, cfqq);
cfq_clear_cfqq_wait_request(cfqq);
cfq_clear_cfqq_wait_busy(cfqq);
@@ -1857,6 +1911,7 @@ static void cfq_arm_slice_timer(struct cfq_data *cfqd)
sl = cfqd->cfq_slice_idle;
mod_timer(&cfqd->idle_slice_timer, jiffies + sl);
+ blkiocg_update_set_idle_time_stats(&cfqq->cfqg->blkg);
cfq_log_cfqq(cfqd, cfqq, "arm_idle: %lu", sl);
}
@@ -1876,7 +1931,8 @@ static void cfq_dispatch_insert(struct request_queue *q, struct request *rq)
elv_dispatch_sort(q, rq);
cfqd->rq_in_flight[cfq_cfqq_sync(cfqq)]++;
- cfqq->nr_sectors += blk_rq_sectors(rq);
+ blkiocg_update_dispatch_stats(&cfqq->cfqg->blkg, blk_rq_bytes(rq),
+ rq_data_dir(rq), rq_is_sync(rq));
}
/*
@@ -2476,11 +2532,12 @@ static void cfq_cic_free(struct cfq_io_context *cic)
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(!cic->dead_key);
+ BUG_ON(!(dead_key & CIC_DEAD_KEY));
spin_lock_irqsave(&ioc->lock, flags);
- radix_tree_delete(&ioc->radix_root, cic->dead_key);
+ radix_tree_delete(&ioc->radix_root, dead_key >> CIC_DEAD_INDEX_SHIFT);
hlist_del_rcu(&cic->cic_list);
spin_unlock_irqrestore(&ioc->lock, flags);
@@ -2503,15 +2560,10 @@ static void cfq_free_io_context(struct io_context *ioc)
__call_for_each_cic(ioc, cic_free_func);
}
-static void cfq_exit_cfqq(struct cfq_data *cfqd, struct cfq_queue *cfqq)
+static void cfq_put_cooperator(struct cfq_queue *cfqq)
{
struct cfq_queue *__cfqq, *next;
- if (unlikely(cfqq == cfqd->active_queue)) {
- __cfq_slice_expired(cfqd, cfqq, 0);
- cfq_schedule_dispatch(cfqd);
- }
-
/*
* If this queue was scheduled to merge with another queue, be
* sure to drop the reference taken on that queue (and others in
@@ -2527,6 +2579,16 @@ static void cfq_exit_cfqq(struct cfq_data *cfqd, struct cfq_queue *cfqq)
cfq_put_queue(__cfqq);
__cfqq = next;
}
+}
+
+static void cfq_exit_cfqq(struct cfq_data *cfqd, struct cfq_queue *cfqq)
+{
+ if (unlikely(cfqq == cfqd->active_queue)) {
+ __cfq_slice_expired(cfqd, cfqq, 0);
+ cfq_schedule_dispatch(cfqd);
+ }
+
+ cfq_put_cooperator(cfqq);
cfq_put_queue(cfqq);
}
@@ -2539,11 +2601,10 @@ static void __cfq_exit_single_io_context(struct cfq_data *cfqd,
list_del_init(&cic->queue_list);
/*
- * Make sure key == NULL is seen for dead queues
+ * Make sure dead mark is seen for dead queues
*/
smp_wmb();
- cic->dead_key = (unsigned long) cic->key;
- cic->key = NULL;
+ cic->key = cfqd_dead_key(cfqd);
if (ioc->ioc_data == cic)
rcu_assign_pointer(ioc->ioc_data, NULL);
@@ -2562,7 +2623,7 @@ 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->key;
+ struct cfq_data *cfqd = cic_to_cfqd(cic);
if (cfqd) {
struct request_queue *q = cfqd->queue;
@@ -2575,7 +2636,7 @@ static void cfq_exit_single_io_context(struct io_context *ioc,
* race between exiting task and queue
*/
smp_read_barrier_depends();
- if (cic->key)
+ if (cic->key == cfqd)
__cfq_exit_single_io_context(cfqd, cic);
spin_unlock_irqrestore(q->queue_lock, flags);
@@ -2655,7 +2716,7 @@ static void cfq_init_prio_data(struct cfq_queue *cfqq, struct io_context *ioc)
static void changed_ioprio(struct io_context *ioc, struct cfq_io_context *cic)
{
- struct cfq_data *cfqd = cic->key;
+ struct cfq_data *cfqd = cic_to_cfqd(cic);
struct cfq_queue *cfqq;
unsigned long flags;
@@ -2712,7 +2773,7 @@ static void cfq_init_cfqq(struct cfq_data *cfqd, struct cfq_queue *cfqq,
static void changed_cgroup(struct io_context *ioc, struct cfq_io_context *cic)
{
struct cfq_queue *sync_cfqq = cic_to_cfqq(cic, 1);
- struct cfq_data *cfqd = cic->key;
+ struct cfq_data *cfqd = cic_to_cfqd(cic);
unsigned long flags;
struct request_queue *q;
@@ -2849,12 +2910,13 @@ cfq_drop_dead_cic(struct cfq_data *cfqd, struct io_context *ioc,
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(ioc->ioc_data == cic);
- radix_tree_delete(&ioc->radix_root, (unsigned long) cfqd);
+ radix_tree_delete(&ioc->radix_root, cfqd->cic_index);
hlist_del_rcu(&cic->cic_list);
spin_unlock_irqrestore(&ioc->lock, flags);
@@ -2866,7 +2928,6 @@ cfq_cic_lookup(struct cfq_data *cfqd, struct io_context *ioc)
{
struct cfq_io_context *cic;
unsigned long flags;
- void *k;
if (unlikely(!ioc))
return NULL;
@@ -2883,13 +2944,11 @@ cfq_cic_lookup(struct cfq_data *cfqd, struct io_context *ioc)
}
do {
- cic = radix_tree_lookup(&ioc->radix_root, (unsigned long) cfqd);
+ cic = radix_tree_lookup(&ioc->radix_root, cfqd->cic_index);
rcu_read_unlock();
if (!cic)
break;
- /* ->key must be copied to avoid race with cfq_exit_queue() */
- k = cic->key;
- if (unlikely(!k)) {
+ if (unlikely(cic->key != cfqd)) {
cfq_drop_dead_cic(cfqd, ioc, cic);
rcu_read_lock();
continue;
@@ -2922,7 +2981,7 @@ static int cfq_cic_link(struct cfq_data *cfqd, struct io_context *ioc,
spin_lock_irqsave(&ioc->lock, flags);
ret = radix_tree_insert(&ioc->radix_root,
- (unsigned long) cfqd, cic);
+ cfqd->cic_index, cic);
if (!ret)
hlist_add_head_rcu(&cic->cic_list, &ioc->cic_list);
spin_unlock_irqrestore(&ioc->lock, flags);
@@ -3185,11 +3244,14 @@ cfq_rq_enqueued(struct cfq_data *cfqd, struct cfq_queue *cfqq,
if (cfq_cfqq_wait_request(cfqq)) {
if (blk_rq_bytes(rq) > PAGE_CACHE_SIZE ||
cfqd->busy_queues > 1) {
- del_timer(&cfqd->idle_slice_timer);
+ cfq_del_timer(cfqd, cfqq);
cfq_clear_cfqq_wait_request(cfqq);
__blk_run_queue(cfqd->queue);
- } else
+ } else {
+ blkiocg_update_idle_time_stats(
+ &cfqq->cfqg->blkg);
cfq_mark_cfqq_must_dispatch(cfqq);
+ }
}
} else if (cfq_should_preempt(cfqd, cfqq, rq)) {
/*
@@ -3214,7 +3276,9 @@ static void cfq_insert_request(struct request_queue *q, struct request *rq)
rq_set_fifo_time(rq, jiffies + cfqd->cfq_fifo_expire[rq_is_sync(rq)]);
list_add_tail(&rq->queuelist, &cfqq->fifo);
cfq_add_rq_rb(rq);
-
+ blkiocg_update_io_add_stats(&(RQ_CFQG(rq))->blkg,
+ &cfqd->serving_group->blkg, rq_data_dir(rq),
+ rq_is_sync(rq));
cfq_rq_enqueued(cfqd, cfqq, rq);
}
@@ -3300,6 +3364,9 @@ static void cfq_completed_request(struct request_queue *q, struct request *rq)
WARN_ON(!cfqq->dispatched);
cfqd->rq_in_driver--;
cfqq->dispatched--;
+ blkiocg_update_completion_stats(&cfqq->cfqg->blkg, rq_start_time_ns(rq),
+ rq_io_start_time_ns(rq), rq_data_dir(rq),
+ rq_is_sync(rq));
cfqd->rq_in_flight[cfq_cfqq_sync(cfqq)]--;
@@ -3440,6 +3507,10 @@ static void cfq_put_request(struct request *rq)
rq->elevator_private = NULL;
rq->elevator_private2 = NULL;
+ /* Put down rq reference on cfqg */
+ cfq_put_cfqg(RQ_CFQG(rq));
+ rq->elevator_private3 = NULL;
+
cfq_put_queue(cfqq);
}
}
@@ -3470,6 +3541,9 @@ split_cfqq(struct cfq_io_context *cic, struct cfq_queue *cfqq)
}
cic_set_cfqq(cic, NULL, 1);
+
+ cfq_put_cooperator(cfqq);
+
cfq_put_queue(cfqq);
return NULL;
}
@@ -3528,6 +3602,7 @@ new_queue:
rq->elevator_private = cic;
rq->elevator_private2 = cfqq;
+ rq->elevator_private3 = cfq_ref_get_cfqg(cfqq->cfqg);
return 0;
queue_fail:
@@ -3661,10 +3736,32 @@ 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. */
call_rcu(&cfqd->rcu, cfq_cfqd_free);
}
+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;
@@ -3672,10 +3769,16 @@ 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)
return NULL;
+ cfqd->cic_index = i;
+
/* Init root service tree */
cfqd->grp_service_tree = CFQ_RB_ROOT;
@@ -3743,7 +3846,6 @@ static void *cfq_init_queue(struct request_queue *q)
* second, in order to have larger depth for async operations.
*/
cfqd->last_delayed_sync = jiffies - HZ;
- INIT_RCU_HEAD(&cfqd->rcu);
return cfqd;
}
@@ -3872,6 +3974,7 @@ static struct elevator_type iosched_cfq = {
.elevator_merged_fn = cfq_merged_request,
.elevator_merge_req_fn = cfq_merged_requests,
.elevator_allow_merge_fn = cfq_allow_merge,
+ .elevator_bio_merged_fn = cfq_bio_merged,
.elevator_dispatch_fn = cfq_dispatch_requests,
.elevator_add_req_fn = cfq_insert_request,
.elevator_activate_req_fn = cfq_activate_request,
@@ -3937,6 +4040,7 @@ static void __exit cfq_exit(void)
*/
if (elv_ioc_count_read(cfq_ioc_count))
wait_for_completion(&all_gone);
+ ida_destroy(&cic_index_ida);
cfq_slab_kill();
}