diff --git a/block/blk-core.c b/block/blk-core.c
index bbd3d4560458f431f8cf4bf37e59b5bce47be12d..f5f419dd8ab6a8c7a93e565c6eaa74cdccd0242e 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -1292,13 +1292,24 @@ void blk_account_io_done(struct request *req, u64 now)
 	    !(req->rq_flags & RQF_FLUSH_SEQ)) {
 		const int sgrp = op_stat_group(req_op(req));
 		struct hd_struct *part;
+		u64 stat_time;
 
 		part_stat_lock();
 		part = req->part;
-
 		update_io_ticks(part, jiffies, true);
 		part_stat_inc(part, ios[sgrp]);
-		part_stat_add(part, nsecs[sgrp], now - req->start_time_ns);
+		stat_time = READ_ONCE(req->stat_time_ns);
+		/*
+		 * This might fail if 'req->stat_time_ns' is updated
+		 * in blk_mq_check_inflight_with_stat().
+		 */
+		if (likely(cmpxchg64(&req->stat_time_ns, stat_time, now)
+			   == stat_time)) {
+			u64 duation = stat_time ? now - stat_time :
+				now - req->start_time_ns;
+
+			part_stat_add(req->part, nsecs[sgrp], duation);
+		}
 		part_stat_unlock();
 
 		hd_struct_put(part);
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 83193e44aada9d91e4c58905f7af3a857c8e4085..2cf387697a4172187f5762dfcbf88e72834ac981 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -102,6 +102,50 @@ struct mq_inflight {
 	unsigned int inflight[2];
 };
 
+static bool blk_mq_check_inflight_with_stat(struct blk_mq_hw_ctx *hctx,
+					    struct request *rq, void *priv,
+					    bool reserved)
+{
+	struct mq_inflight *mi = priv;
+
+	if ((!mi->part->partno || rq->part == mi->part) &&
+	    blk_mq_rq_state(rq) == MQ_RQ_IN_FLIGHT) {
+		u64 stat_time;
+
+		mi->inflight[rq_data_dir(rq)]++;
+		if (!rq->part)
+			return true;
+
+		stat_time = READ_ONCE(rq->stat_time_ns);
+		/*
+		 * This might fail if 'req->stat_time_ns' is updated in
+		 * blk_account_io_done().
+		 */
+		if (likely(cmpxchg64(&rq->stat_time_ns, stat_time,
+				   rq->part->stat_time) == stat_time)) {
+			int sgrp = op_stat_group(req_op(rq));
+			u64 duation = stat_time ?
+				rq->part->stat_time - stat_time :
+				rq->part->stat_time - rq->start_time_ns;
+
+			part_stat_add(rq->part, nsecs[sgrp], duation);
+		}
+	}
+
+	return true;
+}
+
+unsigned int blk_mq_in_flight_with_stat(struct request_queue *q,
+					struct hd_struct *part)
+{
+	struct mq_inflight mi = { .part = part };
+
+	blk_mq_queue_tag_busy_iter(q, blk_mq_check_inflight_with_stat, &mi);
+
+	return mi.inflight[0] + mi.inflight[1];
+}
+
+
 static bool blk_mq_check_inflight(struct blk_mq_hw_ctx *hctx,
 				  struct request *rq, void *priv,
 				  bool reserved)
@@ -328,6 +372,7 @@ static struct request *blk_mq_rq_ctx_init(struct blk_mq_alloc_data *data,
 		rq->start_time_ns = ktime_get_ns();
 	else
 		rq->start_time_ns = 0;
+	rq->stat_time_ns = 0;
 	rq->io_start_time_ns = 0;
 	rq->stats_sectors = 0;
 	rq->nr_phys_segments = 0;
diff --git a/block/blk-mq.h b/block/blk-mq.h
index bb58c68b8274ddfb0778f8235acdd48e07e2254f..6897b4c09b7cfefd759c73b834a4e00c64d202b0 100644
--- a/block/blk-mq.h
+++ b/block/blk-mq.h
@@ -187,6 +187,8 @@ static inline bool blk_mq_hw_queue_mapped(struct blk_mq_hw_ctx *hctx)
 unsigned int blk_mq_in_flight(struct request_queue *q, struct hd_struct *part);
 void blk_mq_in_flight_rw(struct request_queue *q, struct hd_struct *part,
 			 unsigned int inflight[2]);
+unsigned int blk_mq_in_flight_with_stat(struct request_queue *q,
+					struct hd_struct *part);
 
 static inline void blk_mq_put_dispatch_budget(struct request_queue *q)
 {
diff --git a/block/genhd.c b/block/genhd.c
index f94152e99876b5314f1b0201f142afdffdd8d949..16ad881172d01219d4b66d98c29cd8317252ea26 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -1293,25 +1293,52 @@ ssize_t part_size_show(struct device *dev,
 		(unsigned long long)part_nr_sects_read(p));
 }
 
+static void part_set_stat_time(struct hd_struct *hd)
+{
+	u64 now = ktime_get_ns();
+
+again:
+	hd->stat_time = now;
+	if (hd->partno) {
+		hd = &part_to_disk(hd)->part0;
+		goto again;
+	}
+}
+
+static void part_get_stat_info(struct hd_struct *hd, struct disk_stats *stat,
+			       unsigned int *inflight)
+{
+	struct request_queue *q = part_to_disk(hd)->queue;
+
+	if (queue_is_mq(q)) {
+		part_stat_lock();
+		spin_lock(&hd->bd_stat_lock);
+		part_set_stat_time(hd);
+		*inflight = blk_mq_in_flight_with_stat(q, hd);
+		spin_unlock(&hd->bd_stat_lock);
+		part_stat_unlock();
+	} else {
+		*inflight = part_in_flight(hd);
+	}
+
+	if (*inflight) {
+		part_stat_lock();
+		update_io_ticks(hd, jiffies, true);
+		part_stat_unlock();
+	}
+
+	part_stat_read_all(hd, stat);
+}
+
 ssize_t part_stat_show(struct device *dev,
 		       struct device_attribute *attr, char *buf)
 {
 	struct hd_struct *p = dev_to_part(dev);
-	struct request_queue *q = part_to_disk(p)->queue;
 	struct disk_stats stat;
 	unsigned int inflight;
 
-	if (queue_is_mq(q))
-		inflight = blk_mq_in_flight(q, p);
-	else
-		inflight = part_in_flight(p);
+	part_get_stat_info(p, &stat, &inflight);
 
-	if (inflight) {
-		part_stat_lock();
-		update_io_ticks(p, jiffies, true);
-		part_stat_unlock();
-	}
-	part_stat_read_all(p, &stat);
 	return sprintf(buf,
 		"%8lu %8lu %8llu %8u "
 		"%8lu %8lu %8llu %8u "
@@ -1628,17 +1655,7 @@ static int diskstats_show(struct seq_file *seqf, void *v)
 
 	disk_part_iter_init(&piter, gp, DISK_PITER_INCL_EMPTY_PART0);
 	while ((hd = disk_part_iter_next(&piter))) {
-		if (queue_is_mq(gp->queue))
-			inflight = blk_mq_in_flight(gp->queue, hd);
-		else
-			inflight = part_in_flight(hd);
-
-		if (inflight) {
-			part_stat_lock();
-			update_io_ticks(hd, jiffies, true);
-			part_stat_unlock();
-		}
-		part_stat_read_all(hd, &stat);
+		part_get_stat_info(hd, &stat, &inflight);
 		seq_printf(seqf, "%4d %7d %s "
 			   "%lu %lu %lu %u "
 			   "%lu %lu %lu %u "
diff --git a/block/partitions/core.c b/block/partitions/core.c
index 569b0ca9f6e1a115f1b517207d2d8ef4b66c0fe6..92c723c19bb0baabf2baf48fdc3bf2e8444ca0ac 100644
--- a/block/partitions/core.c
+++ b/block/partitions/core.c
@@ -415,6 +415,8 @@ static struct hd_struct *add_partition(struct gendisk *disk, int partno,
 	p->nr_sects = len;
 	p->partno = partno;
 	p->read_only = get_disk_ro(disk) | test_bit(partno, disk->user_ro_bitmap);
+	p->stat_time = 0;
+	spin_lock_init(&p->bd_stat_lock);
 
 	if (info) {
 		struct partition_meta_info *pinfo;
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 6a4b2a01a46216ca7971629074c626372189ef11..46feee6bd45c6e0b238ba77833f2682a51b5f9f1 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -207,7 +207,8 @@ struct request {
 	u64 start_time_ns;
 	/* Time that I/O was submitted to the device. */
 	u64 io_start_time_ns;
-
+	/* Time that I/O was counted in part_get_stat_info(). */
+	u64 stat_time_ns;
 #ifdef CONFIG_BLK_WBT
 	unsigned short wbt_flags;
 #endif
diff --git a/include/linux/genhd.h b/include/linux/genhd.h
index 09da27361620cd34e4407d118456825a3f16fb50..07122c79210c5a669044175620f9e65340a7f805 100644
--- a/include/linux/genhd.h
+++ b/include/linux/genhd.h
@@ -63,6 +63,8 @@ struct hd_struct {
 	seqcount_t nr_sects_seq;
 #endif
 	unsigned long stamp;
+	spinlock_t bd_stat_lock;
+	u64 stat_time;
 	struct disk_stats __percpu *dkstats;
 	struct percpu_ref ref;