[PATCH] md: Collect device IO statistics for MD personalities.

From: NeilBrown <neilb@cse.unsw.edu.au>

Update {read,write}{s,_sectors} on each request to an MD array.

drivers/md/linear.c

@@ -208,6 +208,14 @@ static int linear_make_request (request_queue_t *q, struct bio *bio)
 	dev_info_t *tmp_dev;
 	sector_t block;
 
+	if (bio_data_dir(bio)==WRITE) {
+		disk_stat_inc(mddev->gendisk, writes);
+		disk_stat_add(mddev->gendisk, write_sectors, bio_sectors(bio));
+	} else {
+		disk_stat_inc(mddev->gendisk, reads);
+		disk_stat_add(mddev->gendisk, read_sectors, bio_sectors(bio));
+	}
+
 	tmp_dev = which_dev(mddev, bio->bi_sector);
 	block = bio->bi_sector >> 1;
   

drivers/md/multipath.c

@@ -167,6 +167,13 @@ static int multipath_make_request (request_queue_t *q, struct bio * bio)
 	mp_bh->master_bio = bio;
 	mp_bh->mddev = mddev;
 
+	if (bio_data_dir(bio)==WRITE) {
+		disk_stat_inc(mddev->gendisk, writes);
+		disk_stat_add(mddev->gendisk, write_sectors, bio_sectors(bio));
+	} else {
+		disk_stat_inc(mddev->gendisk, reads);
+		disk_stat_add(mddev->gendisk, read_sectors, bio_sectors(bio));
+	}
 	/*
 	 * read balancing logic:
 	 */

drivers/md/raid0.c

@@ -365,6 +365,14 @@ static int raid0_make_request (request_queue_t *q, struct bio *bio)
 	unsigned long chunk;
 	sector_t block, rsect;
 
+	if (bio_data_dir(bio)==WRITE) {
+		disk_stat_inc(mddev->gendisk, writes);
+		disk_stat_add(mddev->gendisk, write_sectors, bio_sectors(bio));
+	} else {
+		disk_stat_inc(mddev->gendisk, reads);
+		disk_stat_add(mddev->gendisk, read_sectors, bio_sectors(bio));
+	}
+
 	chunk_size = mddev->chunk_size >> 10;
 	chunk_sects = mddev->chunk_size >> 9;
 	chunksize_bits = ffz(~chunk_size);

drivers/md/raid1.c

@@ -474,6 +474,14 @@ static int make_request(request_queue_t *q, struct bio * bio)
 	conf->nr_pending++;
 	spin_unlock_irq(&conf->resync_lock);
 
+	if (bio_data_dir(bio)==WRITE) {
+		disk_stat_inc(mddev->gendisk, writes);
+		disk_stat_add(mddev->gendisk, write_sectors, bio_sectors(bio));
+	} else {
+		disk_stat_inc(mddev->gendisk, reads);
+		disk_stat_add(mddev->gendisk, read_sectors, bio_sectors(bio));
+	}
+
 	/*
 	 * make_request() can abort the operation when READA is being
 	 * used and no empty request is available.

drivers/md/raid5.c

@@ -1326,6 +1326,14 @@ static int make_request (request_queue_t *q, struct bio * bi)
 	sector_t logical_sector, last_sector;
 	struct stripe_head *sh;
 
+	if (bio_data_dir(bi)==WRITE) {
+		disk_stat_inc(mddev->gendisk, writes);
+		disk_stat_add(mddev->gendisk, write_sectors, bio_sectors(bi));
+	} else {
+		disk_stat_inc(mddev->gendisk, reads);
+		disk_stat_add(mddev->gendisk, read_sectors, bio_sectors(bi));
+	}
+
 	logical_sector = bi->bi_sector & ~(STRIPE_SECTORS-1);
 	last_sector = bi->bi_sector + (bi->bi_size>>9);
 

drivers/md/raid6main.c

@@ -1488,6 +1488,14 @@ static int make_request (request_queue_t *q, struct bio * bi)
 	sector_t logical_sector, last_sector;
 	struct stripe_head *sh;
 
+	if (bio_data_dir(bi)==WRITE) {
+		disk_stat_inc(mddev->gendisk, writes);
+		disk_stat_add(mddev->gendisk, write_sectors, bio_sectors(bi));
+	} else {
+		disk_stat_inc(mddev->gendisk, reads);
+		disk_stat_add(mddev->gendisk, read_sectors, bio_sectors(bi));
+	}
+
 	logical_sector = bi->bi_sector & ~(STRIPE_SECTORS-1);
 	last_sector = bi->bi_sector + (bi->bi_size>>9);