1 files changed, 77 insertions, 23 deletions

diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index baef5fc7cff..d148ccbc36d 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -92,6 +92,12 @@ struct cfq_data {
 	struct cfq_queue *active_queue;
 	struct cfq_io_context *active_cic;
 
+	/*
+	 * async queue for each priority case
+	 */
+	struct cfq_queue *async_cfqq[2][IOPRIO_BE_NR];
+	struct cfq_queue *async_idle_cfqq;
+
 	struct timer_list idle_class_timer;
 
 	sector_t last_position;
@@ -109,9 +115,6 @@ struct cfq_data {
 	unsigned int cfq_slice_idle;
 
 	struct list_head cic_list;
-
-	sector_t new_seek_mean;
-	u64 new_seek_total;
 };
 
 /*
@@ -151,8 +154,6 @@ struct cfq_queue {
 
 	/* various state flags, see below */
 	unsigned int flags;
-
-	sector_t last_request_pos;
 };
 
 enum cfqq_state_flags {
@@ -1249,9 +1250,9 @@ 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, cfqd->queue->node);
+	cic = kmem_cache_alloc_node(cfq_ioc_pool, gfp_mask | __GFP_ZERO,
+							cfqd->queue->node);
 	if (cic) {
-		memset(cic, 0, sizeof(*cic));
 		cic->last_end_request = jiffies;
 		INIT_LIST_HEAD(&cic->queue_list);
 		cic->dtor = cfq_free_io_context;
@@ -1351,8 +1352,8 @@ static void cfq_ioc_set_ioprio(struct io_context *ioc)
 }
 
 static struct cfq_queue *
-cfq_get_queue(struct cfq_data *cfqd, int is_sync, struct task_struct *tsk,
-	      gfp_t gfp_mask)
+cfq_find_alloc_queue(struct cfq_data *cfqd, int is_sync,
+		     struct task_struct *tsk, gfp_t gfp_mask)
 {
 	struct cfq_queue *cfqq, *new_cfqq = NULL;
 	struct cfq_io_context *cic;
@@ -1374,17 +1375,19 @@ retry:
 			 * free memory.
 			 */
 			spin_unlock_irq(cfqd->queue->queue_lock);
-			new_cfqq = kmem_cache_alloc_node(cfq_pool, gfp_mask|__GFP_NOFAIL, cfqd->queue->node);
+			new_cfqq = kmem_cache_alloc_node(cfq_pool,
+					gfp_mask | __GFP_NOFAIL | __GFP_ZERO,
+					cfqd->queue->node);
 			spin_lock_irq(cfqd->queue->queue_lock);
 			goto retry;
 		} else {
-			cfqq = kmem_cache_alloc_node(cfq_pool, gfp_mask, cfqd->queue->node);
+			cfqq = kmem_cache_alloc_node(cfq_pool,
+					gfp_mask | __GFP_ZERO,
+					cfqd->queue->node);
 			if (!cfqq)
 				goto out;
 		}
 
-		memset(cfqq, 0, sizeof(*cfqq));
-
 		RB_CLEAR_NODE(&cfqq->rb_node);
 		INIT_LIST_HEAD(&cfqq->fifo);
 
@@ -1405,12 +1408,55 @@ retry:
 	if (new_cfqq)
 		kmem_cache_free(cfq_pool, new_cfqq);
 
-	atomic_inc(&cfqq->ref);
 out:
 	WARN_ON((gfp_mask & __GFP_WAIT) && !cfqq);
 	return cfqq;
 }
 
+static struct cfq_queue **
+cfq_async_queue_prio(struct cfq_data *cfqd, int ioprio_class, int ioprio)
+{
+	switch(ioprio_class) {
+	case IOPRIO_CLASS_RT:
+		return &cfqd->async_cfqq[0][ioprio];
+	case IOPRIO_CLASS_BE:
+		return &cfqd->async_cfqq[1][ioprio];
+	case IOPRIO_CLASS_IDLE:
+		return &cfqd->async_idle_cfqq;
+	default:
+		BUG();
+	}
+}
+
+static struct cfq_queue *
+cfq_get_queue(struct cfq_data *cfqd, int is_sync, struct task_struct *tsk,
+	      gfp_t gfp_mask)
+{
+	const int ioprio = task_ioprio(tsk);
+	const int ioprio_class = task_ioprio_class(tsk);
+	struct cfq_queue **async_cfqq = NULL;
+	struct cfq_queue *cfqq = NULL;
+
+	if (!is_sync) {
+		async_cfqq = cfq_async_queue_prio(cfqd, ioprio_class, ioprio);
+		cfqq = *async_cfqq;
+	}
+
+	if (!cfqq)
+		cfqq = cfq_find_alloc_queue(cfqd, is_sync, tsk, gfp_mask);
+
+	/*
+	 * pin the queue now that it's allocated, scheduler exit will prune it
+	 */
+	if (!is_sync && !(*async_cfqq)) {
+		atomic_inc(&cfqq->ref);
+		*async_cfqq = cfqq;
+	}
+
+	atomic_inc(&cfqq->ref);
+	return cfqq;
+}
+
 /*
  * We drop cfq io contexts lazily, so we may find a dead one.
  */
@@ -1570,11 +1616,6 @@ cfq_update_io_seektime(struct cfq_data *cfqd, struct cfq_io_context *cic,
 	else
 		sdist = cic->last_request_pos - rq->sector;
 
-	if (!cic->seek_samples) {
-		cfqd->new_seek_total = (7*cic->seek_total + (u64)256*sdist) / 8;
-		cfqd->new_seek_mean = cfqd->new_seek_total / 256;
-	}
-
 	/*
 	 * Don't allow the seek distance to get too large from the
 	 * odd fragment, pagein, etc
@@ -1710,7 +1751,6 @@ cfq_rq_enqueued(struct cfq_data *cfqd, struct cfq_queue *cfqq,
 	cfq_update_idle_window(cfqd, cfqq, cic);
 
 	cic->last_request_pos = rq->sector + rq->nr_sectors;
-	cfqq->last_request_pos = cic->last_request_pos;
 
 	if (cfqq == cfqd->active_queue) {
 		/*
@@ -2015,6 +2055,20 @@ static void cfq_shutdown_timer_wq(struct cfq_data *cfqd)
 	blk_sync_queue(cfqd->queue);
 }
 
+static void cfq_put_async_queues(struct cfq_data *cfqd)
+{
+	int i;
+
+	for (i = 0; i < IOPRIO_BE_NR; i++) {
+		if (cfqd->async_cfqq[0][i])
+			cfq_put_queue(cfqd->async_cfqq[0][i]);
+		if (cfqd->async_cfqq[1][i])
+			cfq_put_queue(cfqd->async_cfqq[1][i]);
+		if (cfqd->async_idle_cfqq)
+			cfq_put_queue(cfqd->async_idle_cfqq);
+	}
+}
+
 static void cfq_exit_queue(elevator_t *e)
 {
 	struct cfq_data *cfqd = e->elevator_data;
@@ -2035,6 +2089,8 @@ static void cfq_exit_queue(elevator_t *e)
 		__cfq_exit_single_io_context(cfqd, cic);
 	}
 
+	cfq_put_async_queues(cfqd);
+
 	spin_unlock_irq(q->queue_lock);
 
 	cfq_shutdown_timer_wq(cfqd);
@@ -2046,12 +2102,10 @@ static void *cfq_init_queue(request_queue_t *q)
 {
 	struct cfq_data *cfqd;
 
-	cfqd = kmalloc_node(sizeof(*cfqd), GFP_KERNEL, q->node);
+	cfqd = kmalloc_node(sizeof(*cfqd), GFP_KERNEL | __GFP_ZERO, q->node);
 	if (!cfqd)
 		return NULL;
 
-	memset(cfqd, 0, sizeof(*cfqd));
-
 	cfqd->service_tree = CFQ_RB_ROOT;
 	INIT_LIST_HEAD(&cfqd->cic_list);