Commit d89dbefb authored by Josef Bacik's avatar Josef Bacik Committed by David Sterba
Browse files

btrfs: check if there are free block groups for commit 



may_commit_transaction will skip committing the transaction if we don't
have enough pinned space or if we're trying to find space for a SYSTEM
chunk.  However, if we have pending free block groups in this transaction
we still want to commit as we may be able to allocate a chunk to make
our reservation.  So instead of just returning ENOSPC, check if we have
free block groups pending, and if so commit the transaction to allow us
to use that free space.

Reviewed-by: default avatarOmar Sandoval <osandov@fb.com>
Reviewed-by: default avatarNikolay Borisov <nborisov@suse.com>
Signed-off-by: default avatarJosef Bacik <josef@toxicpanda.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent 3f93aef5

fs/btrfs/extent-tree.c

+19 −12
Original line number Diff line number Diff line
@@ -4865,8 +4865,17 @@ static int may_commit_transaction(struct btrfs_fs_info *fs_info, 
	if (!bytes_needed)

		return 0;



	/* See if there is enough pinned space to make this reservation */

	if (__percpu_counter_compare(&space_info->total_bytes_pinned,

	trans = btrfs_join_transaction(fs_info->extent_root);

	if (IS_ERR(trans))

		return PTR_ERR(trans);



	/*

	 * See if there is enough pinned space to make this reservation, or if

	 * we have block groups that are going to be freed, allowing us to

	 * possibly do a chunk allocation the next loop through.

	 */

	if (test_bit(BTRFS_TRANS_HAVE_FREE_BGS, &trans->transaction->flags) ||

	    __percpu_counter_compare(&space_info->total_bytes_pinned,

				     bytes_needed,

				     BTRFS_TOTAL_BYTES_PINNED_BATCH) >= 0)

		goto commit;
@@ -4876,7 +4885,7 @@ static int may_commit_transaction(struct btrfs_fs_info *fs_info, 
	 * this reservation.

	 */

	if (space_info != delayed_rsv->space_info)

		return -ENOSPC;

		goto enospc;



	spin_lock(&delayed_rsv->lock);

	reclaim_bytes += delayed_rsv->reserved;
@@ -4891,16 +4900,14 @@ static int may_commit_transaction(struct btrfs_fs_info *fs_info, 


	if (__percpu_counter_compare(&space_info->total_bytes_pinned,

				   bytes_needed,

				   BTRFS_TOTAL_BYTES_PINNED_BATCH) < 0) {

		return -ENOSPC;

	}

				   BTRFS_TOTAL_BYTES_PINNED_BATCH) < 0)

		goto enospc;



commit:

	trans = btrfs_join_transaction(fs_info->extent_root);

	if (IS_ERR(trans))

		return -ENOSPC;



	return btrfs_commit_transaction(trans);

enospc:

	btrfs_end_transaction(trans);

	return -ENOSPC;

}



/*

CRA Git | Maintained and supported by SUSTech CRA and CCSE