diff --git a/block/bio.c b/block/bio.c
index d94243411ef308b69e085434588d0ef05fd79ca8..b50d3b59c79b47f821ed43b168527d46c932b1aa 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -1706,9 +1706,13 @@ void generic_end_io_acct(struct request_queue *q, int req_op,
 	const int sgrp = op_stat_group(req_op);
 	int cpu = part_stat_lock();
 
-	update_io_ticks(cpu, part, now);
+	if (precise_iostat) {
+		part_round_stats(q, cpu, part);
+	} else {
+		update_io_ticks(cpu, part, now);
+		part_stat_add(cpu, part, time_in_queue, duration);
+	}
 	part_stat_add(cpu, part, nsecs[sgrp], jiffies_to_nsecs(duration));
-	part_stat_add(cpu, part, time_in_queue, duration);
 	part_dec_in_flight(q, part, op_is_write(req_op));
 
 	part_stat_unlock();
diff --git a/block/blk-core.c b/block/blk-core.c
index 41d0b09e9a67317b9571cf1c01334a90fd3361e0..df733e8caa6a1a9e98c33a909a8be018f4f5e4d3 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -56,6 +56,20 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(block_unplug);
 
 DEFINE_IDA(blk_queue_ida);
 
+bool precise_iostat;
+static int __init precise_iostat_setup(char *str)
+{
+	bool precise;
+
+	if (!strtobool(str, &precise)) {
+		precise_iostat = precise;
+		pr_info("precise iostat %d\n", precise_iostat);
+	}
+
+	return 1;
+}
+__setup("precise_iostat=", precise_iostat_setup);
+
 /*
  * For the allocated request tables
  */
@@ -1700,8 +1714,13 @@ static void part_round_stats_single(struct request_queue *q, int cpu,
 				    struct hd_struct *part, unsigned long now,
 				    unsigned int inflight)
 {
-	if (inflight)
+	if (inflight) {
+		if (precise_iostat) {
+			__part_stat_add(cpu, part, time_in_queue,
+					inflight * (now - part->stamp));
+		}
 		__part_stat_add(cpu, part, io_ticks, (now - part->stamp));
+	}
 	part->stamp = now;
 }
 
@@ -2771,10 +2790,15 @@ void blk_account_io_done(struct request *req, u64 now)
 		cpu = part_stat_lock();
 		part = req->part;
 
-		update_io_ticks(cpu, part, jiffies);
+		if (!precise_iostat) {
+			update_io_ticks(cpu, part, jiffies);
+			part_stat_add(cpu, part, time_in_queue,
+				nsecs_to_jiffies64(now - req->start_time_ns));
+		} else {
+			part_round_stats(req->q, cpu, part);
+		}
 		part_stat_inc(cpu, part, ios[sgrp]);
 		part_stat_add(cpu, part, nsecs[sgrp], now - req->start_time_ns);
-		part_stat_add(cpu, part, time_in_queue, nsecs_to_jiffies64(now - req->start_time_ns));
 		part_dec_in_flight(req->q, part, rq_data_dir(req));
 
 		hd_struct_put(part);
diff --git a/block/blk-merge.c b/block/blk-merge.c
index 4c17c1031e34f59353a6d561654ef0d74b71744d..d2fabe1fdf3264d9cf8bb47888da7a30a6a8ccb6 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -669,6 +669,8 @@ static void blk_account_io_merge(struct request *req)
 		cpu = part_stat_lock();
 		part = req->part;
 
+		if (precise_iostat)
+			part_round_stats(req->q, cpu, part);
 		part_dec_in_flight(req->q, part, rq_data_dir(req));
 
 		hd_struct_put(part);
diff --git a/block/genhd.c b/block/genhd.c
index 183612cbbd6b77001f7878614ff8c68bfe95e60d..e7b97fdb417314bc1c526646e0aaa473f6b0937b 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -1352,6 +1352,7 @@ static int diskstats_show(struct seq_file *seqf, void *v)
 	struct hd_struct *hd;
 	char buf[BDEVNAME_SIZE];
 	unsigned int inflight[2];
+	int cpu;
 
 	/*
 	if (&disk_to_dev(gp)->kobj.entry == block_class.devices.next)
@@ -1363,6 +1364,12 @@ 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 (precise_iostat) {
+			cpu = part_stat_lock();
+			part_round_stats(gp->queue, cpu, hd);
+			part_stat_unlock();
+		}
+
 		part_in_flight(gp->queue, hd, inflight);
 		seq_printf(seqf, "%4d %7d %s "
 			   "%lu %lu %lu %u "
diff --git a/block/partition-generic.c b/block/partition-generic.c
index 739c0cc5fd2221ea028caab6ab4d385faa993e07..c4ac7a8c77dc5dd5937794a21b9909f3908a5bad 100644
--- a/block/partition-generic.c
+++ b/block/partition-generic.c
@@ -18,6 +18,7 @@
 #include <linux/ctype.h>
 #include <linux/genhd.h>
 #include <linux/blktrace_api.h>
+#include <linux/blkdev.h>
 
 #include "partitions/check.h"
 
@@ -121,6 +122,13 @@ ssize_t part_stat_show(struct device *dev,
 	struct hd_struct *p = dev_to_part(dev);
 	struct request_queue *q = part_to_disk(p)->queue;
 	unsigned int inflight[2];
+	int cpu;
+
+	if (precise_iostat) {
+		cpu = part_stat_lock();
+		part_round_stats(q, cpu, p);
+		part_stat_unlock();
+	}
 
 	part_in_flight(q, p, inflight);
 	return sprintf(buf,
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 28ea02865ecc1fdec6203143ff08cfbdb520bb4c..a86659e78d98797c7d15bb4dec711b62f72e1f72 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -28,6 +28,7 @@
 #include <linux/scatterlist.h>
 #include <linux/blkzoned.h>
 
+extern bool precise_iostat;
 struct module;
 struct scsi_ioctl_command;