Commit a1a7d05a authored Jan 22, 2021 by Darrick J. Wong

xfs: flush speculative space allocations when we run out of space



If a fs modification (creation, file write, reflink, etc.) is unable to
reserve enough space to handle the modification, try clearing whatever
space the filesystem might have been hanging onto in the hopes of
speeding up the filesystem.  The flushing behavior will become
particularly important when we add deferred inode inactivation because
that will increase the amount of space that isn't actively tied to user
data.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>

parent 85c5b270

fs/xfs/xfs_trans.c

+11 −0

Original line number	Diff line number	Diff line
		@@ -289,6 +289,17 @@ xfs_trans_alloc(
		tp->t_firstblock = NULLFSBLOCK;

		error = xfs_trans_reserve(tp, resp, blocks, rtextents);
		if (error == -ENOSPC) {
		/*
		* We weren't able to reserve enough space for the transaction.
		* Flush the other speculative space allocations to free space.
		* Do not perform a synchronous scan because callers can hold
		* other locks.
		*/
		error = xfs_blockgc_free_space(mp, NULL);
		if (!error)
		error = xfs_trans_reserve(tp, resp, blocks, rtextents);
		}
		if (error) {
		xfs_trans_cancel(tp);
		return error;