Commit 99dfc43e authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Jens Axboe
Browse files

block: use ->bi_bdev for bio based I/O accounting 



Rework the I/O accounting for bio based drivers to use ->bi_bdev.  This
means all drivers can now simply use bio_start_io_acct to start
accounting, and it will take partitions into account automatically.  To
end I/O account either bio_end_io_acct can be used if the driver never
remaps I/O to a different device, or bio_end_io_acct_remapped if the
driver did remap the I/O.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Acked-by: default avatarTejun Heo <tj@kernel.org>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 30c5d345

block/blk-core.c

+13 −10
Original line number Diff line number Diff line
@@ -1321,14 +1321,17 @@ static unsigned long __part_start_io_acct(struct block_device *part, 
	return now;

}



unsigned long part_start_io_acct(struct gendisk *disk, struct block_device **part,

				 struct bio *bio)

/**

 * bio_start_io_acct - start I/O accounting for bio based drivers

 * @bio:	bio to start account for

 *

 * Returns the start time that should be passed back to bio_end_io_acct().

 */

unsigned long bio_start_io_acct(struct bio *bio)

{

	*part = disk_map_sector_rcu(disk, bio->bi_iter.bi_sector);



	return __part_start_io_acct(*part, bio_sectors(bio), bio_op(bio));

	return __part_start_io_acct(bio->bi_bdev, bio_sectors(bio), bio_op(bio));

}

EXPORT_SYMBOL_GPL(part_start_io_acct);

EXPORT_SYMBOL_GPL(bio_start_io_acct);



unsigned long disk_start_io_acct(struct gendisk *disk, unsigned int sectors,

				 unsigned int op)
@@ -1351,12 +1354,12 @@ static void __part_end_io_acct(struct block_device *part, unsigned int op, 
	part_stat_unlock();

}



void part_end_io_acct(struct block_device *part, struct bio *bio,

		      unsigned long start_time)

void bio_end_io_acct_remapped(struct bio *bio, unsigned long start_time,

		struct block_device *orig_bdev)

{

	__part_end_io_acct(part, bio_op(bio), start_time);

	__part_end_io_acct(orig_bdev, bio_op(bio), start_time);

}

EXPORT_SYMBOL_GPL(part_end_io_acct);

EXPORT_SYMBOL_GPL(bio_end_io_acct_remapped);



void disk_end_io_acct(struct gendisk *disk, unsigned int op,

		      unsigned long start_time)

drivers/md/bcache/request.c

+21 −13
Original line number Diff line number Diff line
@@ -475,7 +475,7 @@ struct search { 
	unsigned int		read_dirty_data:1;

	unsigned int		cache_missed:1;



	struct block_device	*part;

	struct block_device	*orig_bdev;

	unsigned long		start_time;



	struct btree_op		op;
@@ -670,8 +670,8 @@ static void bio_complete(struct search *s) 
{

	if (s->orig_bio) {

		/* Count on bcache device */

		part_end_io_acct(s->part, s->orig_bio, s->start_time);



		bio_end_io_acct_remapped(s->orig_bio, s->start_time,

					 s->orig_bdev);

		trace_bcache_request_end(s->d, s->orig_bio);

		s->orig_bio->bi_status = s->iop.status;

		bio_endio(s->orig_bio);
@@ -714,7 +714,8 @@ static void search_free(struct closure *cl) 
}



static inline struct search *search_alloc(struct bio *bio,

					  struct bcache_device *d)

		struct bcache_device *d, struct block_device *orig_bdev,

		unsigned long start_time)

{

	struct search *s;
@@ -732,7 +733,8 @@ static inline struct search *search_alloc(struct bio *bio, 
	s->write		= op_is_write(bio_op(bio));

	s->read_dirty_data	= 0;

	/* Count on the bcache device */

	s->start_time		= part_start_io_acct(d->disk, &s->part, bio);

	s->orig_bdev		= orig_bdev;

	s->start_time		= start_time;

	s->iop.c		= d->c;

	s->iop.bio		= NULL;

	s->iop.inode		= d->id;
@@ -1074,7 +1076,7 @@ struct detached_dev_io_private { 
	unsigned long		start_time;

	bio_end_io_t		*bi_end_io;

	void			*bi_private;

	struct block_device	*part;

	struct block_device	*orig_bdev;

};



static void detached_dev_end_io(struct bio *bio)
@@ -1086,7 +1088,7 @@ static void detached_dev_end_io(struct bio *bio) 
	bio->bi_private = ddip->bi_private;



	/* Count on the bcache device */

	part_end_io_acct(ddip->part, bio, ddip->start_time);

	bio_end_io_acct_remapped(bio, ddip->start_time, ddip->orig_bdev);



	if (bio->bi_status) {

		struct cached_dev *dc = container_of(ddip->d,
@@ -1099,7 +1101,8 @@ static void detached_dev_end_io(struct bio *bio) 
	bio->bi_end_io(bio);

}



static void detached_dev_do_request(struct bcache_device *d, struct bio *bio)

static void detached_dev_do_request(struct bcache_device *d, struct bio *bio,

		struct block_device *orig_bdev, unsigned long start_time)

{

	struct detached_dev_io_private *ddip;

	struct cached_dev *dc = container_of(d, struct cached_dev, disk);
@@ -1112,7 +1115,8 @@ static void detached_dev_do_request(struct bcache_device *d, struct bio *bio) 
	ddip = kzalloc(sizeof(struct detached_dev_io_private), GFP_NOIO);

	ddip->d = d;

	/* Count on the bcache device */

	ddip->start_time = part_start_io_acct(d->disk, &ddip->part, bio);

	ddip->orig_bdev = orig_bdev;

	ddip->start_time = start_time;

	ddip->bi_end_io = bio->bi_end_io;

	ddip->bi_private = bio->bi_private;

	bio->bi_end_io = detached_dev_end_io;
@@ -1168,8 +1172,10 @@ static void quit_max_writeback_rate(struct cache_set *c, 
blk_qc_t cached_dev_submit_bio(struct bio *bio)

{

	struct search *s;

	struct bcache_device *d = bio->bi_bdev->bd_disk->private_data;

	struct block_device *orig_bdev = bio->bi_bdev;

	struct bcache_device *d = orig_bdev->bd_disk->private_data;

	struct cached_dev *dc = container_of(d, struct cached_dev, disk);

	unsigned long start_time;

	int rw = bio_data_dir(bio);



	if (unlikely((d->c && test_bit(CACHE_SET_IO_DISABLE, &d->c->flags)) ||
@@ -1194,11 +1200,13 @@ blk_qc_t cached_dev_submit_bio(struct bio *bio) 
		}

	}



	start_time = bio_start_io_acct(bio);



	bio_set_dev(bio, dc->bdev);

	bio->bi_iter.bi_sector += dc->sb.data_offset;



	if (cached_dev_get(dc)) {

		s = search_alloc(bio, d);

		s = search_alloc(bio, d, orig_bdev, start_time);

		trace_bcache_request_start(s->d, bio);



		if (!bio->bi_iter.bi_size) {
@@ -1219,7 +1227,7 @@ blk_qc_t cached_dev_submit_bio(struct bio *bio) 
		}

	} else

		/* I/O request sent to backing device */

		detached_dev_do_request(d, bio);

		detached_dev_do_request(d, bio, orig_bdev, start_time);



	return BLK_QC_T_NONE;

}
@@ -1283,7 +1291,7 @@ blk_qc_t flash_dev_submit_bio(struct bio *bio) 
		return BLK_QC_T_NONE;

	}



	s = search_alloc(bio, d);

	s = search_alloc(bio, d, bio->bi_bdev, bio_start_io_acct(bio));

	cl = &s->cl;

	bio = &s->bio.bio;

drivers/md/md.c

+4 −4
Original line number Diff line number Diff line
@@ -463,8 +463,8 @@ struct md_io { 
	struct mddev *mddev;

	bio_end_io_t *orig_bi_end_io;

	void *orig_bi_private;

	struct block_device *orig_bi_bdev;

	unsigned long start_time;

	struct block_device *part;

};



static void md_end_io(struct bio *bio)
@@ -472,7 +472,7 @@ static void md_end_io(struct bio *bio) 
	struct md_io *md_io = bio->bi_private;

	struct mddev *mddev = md_io->mddev;



	part_end_io_acct(md_io->part, bio, md_io->start_time);

	bio_end_io_acct_remapped(bio, md_io->start_time, md_io->orig_bi_bdev);



	bio->bi_end_io = md_io->orig_bi_end_io;

	bio->bi_private = md_io->orig_bi_private;
@@ -514,12 +514,12 @@ static blk_qc_t md_submit_bio(struct bio *bio) 
		md_io->mddev = mddev;

		md_io->orig_bi_end_io = bio->bi_end_io;

		md_io->orig_bi_private = bio->bi_private;

		md_io->orig_bi_bdev = bio->bi_bdev;



		bio->bi_end_io = md_end_io;

		bio->bi_private = md_io;



		md_io->start_time = part_start_io_acct(mddev->gendisk,

						       &md_io->part, bio);

		md_io->start_time = bio_start_io_acct(bio);

	}



	/* bio could be mergeable after passing to underlayer */

include/linux/blkdev.h

+4 −17
Original line number Diff line number Diff line
@@ -1954,22 +1954,9 @@ unsigned long disk_start_io_acct(struct gendisk *disk, unsigned int sectors, 
void disk_end_io_acct(struct gendisk *disk, unsigned int op,

		unsigned long start_time);



unsigned long part_start_io_acct(struct gendisk *disk,

		struct block_device **part, struct bio *bio);

void part_end_io_acct(struct block_device *part, struct bio *bio,

		      unsigned long start_time);



/**

 * bio_start_io_acct - start I/O accounting for bio based drivers

 * @bio:	bio to start account for

 *

 * Returns the start time that should be passed back to bio_end_io_acct().

 */

static inline unsigned long bio_start_io_acct(struct bio *bio)

{

	return disk_start_io_acct(bio->bi_bdev->bd_disk, bio_sectors(bio),

				  bio_op(bio));

}

unsigned long bio_start_io_acct(struct bio *bio);

void bio_end_io_acct_remapped(struct bio *bio, unsigned long start_time,

		struct block_device *orig_bdev);



/**

 * bio_end_io_acct - end I/O accounting for bio based drivers
@@ -1978,7 +1965,7 @@ static inline unsigned long bio_start_io_acct(struct bio *bio) 
 */

static inline void bio_end_io_acct(struct bio *bio, unsigned long start_time)

{

	return disk_end_io_acct(bio->bi_bdev->bd_disk, bio_op(bio), start_time);

	return bio_end_io_acct_remapped(bio, start_time, bio->bi_bdev);

}



int bdev_read_only(struct block_device *bdev);