1 files changed, 33 insertions, 16 deletions

diff --git a/block/blk-stat.c b/block/blk-stat.c
index 940f15d600f8..7ff76ae6c76a 100644
--- a/block/blk-stat.c
+++ b/block/blk-stat.c
@@ -6,7 +6,6 @@
  */
 #include <linux/kernel.h>
 #include <linux/rculist.h>
-#include <linux/blk-mq.h>
 
 #include "blk-stat.h"
 #include "blk-mq.h"
@@ -15,7 +14,7 @@
 struct blk_queue_stats {
 	struct list_head callbacks;
 	spinlock_t lock;
-	bool enable_accounting;
+	int accounting;
 };
 
 void blk_rq_stat_init(struct blk_rq_stat *stat)
@@ -53,14 +52,16 @@ void blk_stat_add(struct request *rq, u64 now)
 	struct request_queue *q = rq->q;
 	struct blk_stat_callback *cb;
 	struct blk_rq_stat *stat;
-	int bucket;
+	int bucket, cpu;
 	u64 value;
 
 	value = (now >= rq->io_start_time_ns) ? now - rq->io_start_time_ns : 0;
 
-	blk_throtl_stat_add(rq, value);
+	if (req_op(rq) == REQ_OP_READ || req_op(rq) == REQ_OP_WRITE)
+		blk_throtl_stat_add(rq, value);
 
 	rcu_read_lock();
+	cpu = get_cpu();
 	list_for_each_entry_rcu(cb, &q->stats->callbacks, list) {
 		if (!blk_stat_is_active(cb))
 			continue;
@@ -69,10 +70,10 @@ void blk_stat_add(struct request *rq, u64 now)
 		if (bucket < 0)
 			continue;
 
-		stat = &get_cpu_ptr(cb->cpu_stat)[bucket];
+		stat = &per_cpu_ptr(cb->cpu_stat, cpu)[bucket];
 		blk_rq_stat_add(stat, value);
-		put_cpu_ptr(cb->cpu_stat);
 	}
+	put_cpu();
 	rcu_read_unlock();
 }
 
@@ -136,6 +137,7 @@ void blk_stat_add_callback(struct request_queue *q,
 			   struct blk_stat_callback *cb)
 {
 	unsigned int bucket;
+	unsigned long flags;
 	int cpu;
 
 	for_each_possible_cpu(cpu) {
@@ -146,20 +148,22 @@ void blk_stat_add_callback(struct request_queue *q,
 			blk_rq_stat_init(&cpu_stat[bucket]);
 	}
 
-	spin_lock(&q->stats->lock);
+	spin_lock_irqsave(&q->stats->lock, flags);
 	list_add_tail_rcu(&cb->list, &q->stats->callbacks);
 	blk_queue_flag_set(QUEUE_FLAG_STATS, q);
-	spin_unlock(&q->stats->lock);
+	spin_unlock_irqrestore(&q->stats->lock, flags);
 }
 
 void blk_stat_remove_callback(struct request_queue *q,
 			      struct blk_stat_callback *cb)
 {
-	spin_lock(&q->stats->lock);
+	unsigned long flags;
+
+	spin_lock_irqsave(&q->stats->lock, flags);
 	list_del_rcu(&cb->list);
-	if (list_empty(&q->stats->callbacks) && !q->stats->enable_accounting)
+	if (list_empty(&q->stats->callbacks) && !q->stats->accounting)
 		blk_queue_flag_clear(QUEUE_FLAG_STATS, q);
-	spin_unlock(&q->stats->lock);
+	spin_unlock_irqrestore(&q->stats->lock, flags);
 
 	del_timer_sync(&cb->timer);
 }
@@ -180,12 +184,25 @@ void blk_stat_free_callback(struct blk_stat_callback *cb)
 		call_rcu(&cb->rcu, blk_stat_free_callback_rcu);
 }
 
+void blk_stat_disable_accounting(struct request_queue *q)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&q->stats->lock, flags);
+	if (!--q->stats->accounting && list_empty(&q->stats->callbacks))
+		blk_queue_flag_clear(QUEUE_FLAG_STATS, q);
+	spin_unlock_irqrestore(&q->stats->lock, flags);
+}
+EXPORT_SYMBOL_GPL(blk_stat_disable_accounting);
+
 void blk_stat_enable_accounting(struct request_queue *q)
 {
-	spin_lock(&q->stats->lock);
-	q->stats->enable_accounting = true;
-	blk_queue_flag_set(QUEUE_FLAG_STATS, q);
-	spin_unlock(&q->stats->lock);
+	unsigned long flags;
+
+	spin_lock_irqsave(&q->stats->lock, flags);
+	if (!q->stats->accounting++ && list_empty(&q->stats->callbacks))
+		blk_queue_flag_set(QUEUE_FLAG_STATS, q);
+	spin_unlock_irqrestore(&q->stats->lock, flags);
 }
 EXPORT_SYMBOL_GPL(blk_stat_enable_accounting);
 
@@ -199,7 +216,7 @@ struct blk_queue_stats *blk_alloc_queue_stats(void)
 
 	INIT_LIST_HEAD(&stats->callbacks);
 	spin_lock_init(&stats->lock);
-	stats->enable_accounting = false;
+	stats->accounting = 0;
 
 	return stats;
 }