[PATCH v2] block: make the io_ticks counter more accurate

[Wen Yang <wenyang@linux.alibaba.com>]

Instead of the jiffies, we should update the io_ticks counter
with the passed in parameter 'now'.

Signed-off-by: Wen Yang <wenyang@linux.alibaba.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: linux-block@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
---
v2->v1: Use the same clock source for io_ticks and other statistics in the diskstats

 block/blk-core.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/block/blk-core.c b/block/blk-core.c
index 379f6f5..da7de9f 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -1365,7 +1365,7 @@ void blk_account_io_done(struct request *req, u64 now)
 		part_stat_lock();
 		part = req->part;
 
-		update_io_ticks(part, jiffies);
+		update_io_ticks(part, nsecs_to_jiffies(now));
 		part_stat_inc(part, ios[sgrp]);
 		part_stat_add(part, nsecs[sgrp], now - req->start_time_ns);
 		part_stat_add(part, time_in_queue, nsecs_to_jiffies64(now - req->start_time_ns));
@@ -1407,7 +1407,7 @@ void blk_account_io_start(struct request *rq, bool new_io)
 		rq->part = part;
 	}
 
-	update_io_ticks(part, jiffies);
+	update_io_ticks(part, nsecs_to_jiffies(ktime_get_ns()));
 
 	part_stat_unlock();
 }
-- 
1.8.3.1