raid10: fix leak of io accounting

hulk inclusion
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I6JN04
CVE: NA

--------------------------------

handle_read_error() will resumit r10_bio by raid10_read_request(), which
will call bio_start_io_acct() again, while bio_end_io_acct() will only
be called once.

Fix the problem by don't account io again from handle_read_error().

Fixes: 528bc2cf ("md/raid10: enable io accounting")
Signed-off-by: NYu Kuai <yukuai3@huawei.com>
Reviewed-by: NHou Tao <houtao1@huawei.com>
Signed-off-by: NJialin Zhang <zhangjialin11@huawei.com>

drivers/md/raid10.c

@@ -1117,7 +1117,7 @@ static void regular_request_wait(struct mddev *mddev, struct r10conf *conf,
 }
 
 static void raid10_read_request(struct mddev *mddev, struct bio *bio,
-				struct r10bio *r10_bio)
+				struct r10bio *r10_bio, bool handle_error)
 {
 	struct r10conf *conf = mddev->private;
 	struct bio *read_bio;
@@ -1187,7 +1187,7 @@ static void raid10_read_request(struct mddev *mddev, struct bio *bio,
 	}
 	slot = r10_bio->read_slot;
 
-	if (blk_queue_io_stat(bio->bi_disk->queue))
+	if (!handle_error && blk_queue_io_stat(bio->bi_disk->queue))
 		r10_bio->start_time = bio_start_io_acct(bio);
 	read_bio = bio_clone_fast(bio, gfp, &mddev->bio_set);
 
@@ -1503,7 +1503,7 @@ static void __make_request(struct mddev *mddev, struct bio *bio, int sectors)
 	memset(r10_bio->devs, 0, sizeof(r10_bio->devs[0]) * conf->copies);
 
 	if (bio_data_dir(bio) == READ)
-		raid10_read_request(mddev, bio, r10_bio);
+		raid10_read_request(mddev, bio, r10_bio, false);
 	else
 		raid10_write_request(mddev, bio, r10_bio);
 }
@@ -2597,7 +2597,7 @@ static void handle_read_error(struct mddev *mddev, struct r10bio *r10_bio)
 	rdev_dec_pending(rdev, mddev);
 	allow_barrier(conf);
 	r10_bio->state = 0;
-	raid10_read_request(mddev, r10_bio->master_bio, r10_bio);
+	raid10_read_request(mddev, r10_bio->master_bio, r10_bio, true);
 }
 
 static void handle_write_completed(struct r10conf *conf, struct r10bio *r10_bio)