Commit 7b26410b authored by Song Liu's avatar Song Liu Committed by Jens Axboe
Browse files

block: introduce part_[begin|end]_io_acct 



These functions can be used to enable iostat for partitions on devices
like md, bcache.

Signed-off-by: default avatarSong Liu <songliubraving@fb.com>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 28500850

block/blk-core.c

+33 −6
Original line number Diff line number Diff line
@@ -1324,10 +1324,9 @@ void blk_account_io_start(struct request *rq) 
	part_stat_unlock();

}



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

		unsigned int op)

static unsigned long __part_start_io_acct(struct hd_struct *part,

					  unsigned int sectors, unsigned int op)

{

	struct hd_struct *part = &disk->part0;

	const int sgrp = op_stat_group(op);

	unsigned long now = READ_ONCE(jiffies);
@@ -1340,12 +1339,26 @@ unsigned long disk_start_io_acct(struct gendisk *disk, unsigned int sectors, 


	return now;

}



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

				 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));

}

EXPORT_SYMBOL_GPL(part_start_io_acct);



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

				 unsigned int op)

{

	return __part_start_io_acct(&disk->part0, sectors, op);

}

EXPORT_SYMBOL(disk_start_io_acct);



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

static void __part_end_io_acct(struct hd_struct *part, unsigned int op,

			       unsigned long start_time)

{

	struct hd_struct *part = &disk->part0;

	const int sgrp = op_stat_group(op);

	unsigned long now = READ_ONCE(jiffies);

	unsigned long duration = now - start_time;
@@ -1356,6 +1369,20 @@ void disk_end_io_acct(struct gendisk *disk, unsigned int op, 
	part_stat_local_dec(part, in_flight[op_is_write(op)]);

	part_stat_unlock();

}



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

		      unsigned long start_time)

{

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

	hd_struct_put(part);

}

EXPORT_SYMBOL_GPL(part_end_io_acct);



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

		      unsigned long start_time)

{

	__part_end_io_acct(&disk->part0, op, start_time);

}

EXPORT_SYMBOL(disk_end_io_acct);



/*

include/linux/blkdev.h

+5 −0
Original line number Diff line number Diff line
@@ -1933,6 +1933,11 @@ 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 hd_struct **part,

				 struct bio *bio);

void part_end_io_acct(struct hd_struct *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