Commit 22c59948 authored by Chris Mason's avatar Chris Mason
Browse files

Btrfs: Handle data block end_io through the async work queue 



Before it was done by the bio end_io routine, the work queue code is able
to scale much better with faster IO subsystems.

Signed-off-by: default avatarChris Mason <chris.mason@oracle.com>
parent ce9adaa5

fs/btrfs/disk-io.c

+23 −11
Original line number Diff line number Diff line
@@ -54,6 +54,7 @@ struct end_io_wq { 
	void *private;

	struct btrfs_fs_info *info;

	int error;

	int metadata;

	struct list_head list;

};
@@ -308,29 +309,40 @@ static int end_workqueue_bio(struct bio *bio, 
#endif

}



static int btree_submit_bio_hook(struct inode *inode, int rw, struct bio *bio)

int btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio,

			int metadata)

{

	struct btrfs_root *root = BTRFS_I(inode)->root;

	struct end_io_wq *end_io_wq;

	u64 offset;

	offset = bio->bi_sector << 9;



	if (rw & (1 << BIO_RW)) {

		return btrfs_map_bio(BTRFS_I(inode)->root, rw, bio);

	}



	end_io_wq = kmalloc(sizeof(*end_io_wq), GFP_NOFS);

	if (!end_io_wq)

		return -ENOMEM;



	end_io_wq->private = bio->bi_private;

	end_io_wq->end_io = bio->bi_end_io;

	end_io_wq->info = root->fs_info;

	end_io_wq->info = info;

	end_io_wq->error = 0;

	end_io_wq->bio = bio;

	end_io_wq->metadata = metadata;



	bio->bi_private = end_io_wq;

	bio->bi_end_io = end_workqueue_bio;

	return 0;

}



static int btree_submit_bio_hook(struct inode *inode, int rw, struct bio *bio)

{

	struct btrfs_root *root = BTRFS_I(inode)->root;

	u64 offset;

	int ret;



	offset = bio->bi_sector << 9;



	if (rw & (1 << BIO_RW)) {

		return btrfs_map_bio(BTRFS_I(inode)->root, rw, bio);

	}



	ret = btrfs_bio_wq_end_io(root->fs_info, bio, 1);

	BUG_ON(ret);



	if (offset == BTRFS_SUPER_INFO_OFFSET) {

		bio->bi_bdev = root->fs_info->sb->s_bdev;
@@ -880,7 +892,7 @@ void btrfs_end_io_csum(struct work_struct *work) 
		end_io_wq = list_entry(next, struct end_io_wq, list);



		bio = end_io_wq->bio;

		if (!bio_ready_for_csum(bio)) {

		if (end_io_wq->metadata && !bio_ready_for_csum(bio)) {

			spin_lock_irqsave(&fs_info->end_io_work_lock, flags);

			was_empty = list_empty(&fs_info->end_io_work_list);

			list_add_tail(&end_io_wq->list,

fs/btrfs/disk-io.h

+2 −0
Original line number Diff line number Diff line
@@ -71,4 +71,6 @@ void btrfs_throttle(struct btrfs_root *root); 
int btrfs_open_device(struct btrfs_device *dev);

int btrfs_verify_block_csum(struct btrfs_root *root,

			    struct extent_buffer *buf);

int btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio,

			int metadata);

#endif

fs/btrfs/inode.c

+3 −1
Original line number Diff line number Diff line
@@ -328,7 +328,9 @@ int btrfs_submit_bio_hook(struct inode *inode, int rw, struct bio *bio) 
	struct btrfs_trans_handle *trans;

	int ret = 0;



	if (rw != WRITE) {

	if (!(rw & (1 << BIO_RW))) {

		ret = btrfs_bio_wq_end_io(root->fs_info, bio, 0);

		BUG_ON(ret);

		goto mapit;

	}