Commit f38b46bb authored by Dave Chinner's avatar Dave Chinner
Browse files

xfs: factor out MRU hit case in xfs_filestream_select_ag 



Because it now stands out like a sore thumb. Factoring out this case
starts the process of simplifying xfs_filestream_select_ag() again.

Signed-off-by: default avatarDave Chinner <dchinner@redhat.com>
Reviewed-by: default avatarDarrick J. Wong <djwong@kernel.org>
parent 3e43877a

fs/xfs/xfs_filestream.c

+83 −50
Original line number Diff line number Diff line
@@ -260,75 +260,110 @@ xfs_filestream_get_parent( 
}



/*

 * Search for an allocation group with a single extent large enough for

 * the request.  If one isn't found, then the largest available free extent is

 * returned as the best length possible.

 * Lookup the mru cache for an existing association. If one exists and we can

 * use it, return with the agno and blen indicating that the allocation will

 * proceed with that association.

 *

 * If we have no association, or we cannot use the current one and have to

 * destroy it, return with blen = 0 and agno pointing at the next agno to try.

 */

int

xfs_filestream_select_ag(

xfs_filestream_select_ag_mru(

	struct xfs_bmalloca	*ap,

	struct xfs_alloc_arg	*args,

	struct xfs_inode	*pip,

	xfs_agnumber_t		*agno,

	xfs_extlen_t		*blen)

{

	struct xfs_mount	*mp = ap->ip->i_mount;

	struct xfs_perag	*pag;

	struct xfs_inode	*pip = NULL;

	xfs_agnumber_t		agno = NULLAGNUMBER;

	struct xfs_mru_cache_elem *mru;

	int			flags = 0;

	int			error = 0;



	args->total = ap->total;

	*blen = 0;



	pip = xfs_filestream_get_parent(ap->ip);

	if (!pip) {

		agno = 0;

		goto out_select;

	}

	int			error;



	mru = xfs_mru_cache_lookup(mp->m_filestream, pip->i_ino);

	if (mru) {

		agno = container_of(mru, struct xfs_fstrm_item, mru)->ag;

	if (!mru)

		goto out_default_agno;



	*agno = container_of(mru, struct xfs_fstrm_item, mru)->ag;

	xfs_mru_cache_done(mp->m_filestream);

		mru = NULL;



		trace_xfs_filestream_lookup(mp, ap->ip->i_ino, agno);

		xfs_irele(pip);

	trace_xfs_filestream_lookup(mp, ap->ip->i_ino, *agno);



		ap->blkno = XFS_AGB_TO_FSB(args->mp, agno, 0);

	ap->blkno = XFS_AGB_TO_FSB(args->mp, *agno, 0);

	xfs_bmap_adjacent(ap);



		pag = xfs_perag_grab(mp, agno);

		if (pag) {

	pag = xfs_perag_grab(mp, *agno);

	if (!pag)

		goto out_default_agno;



	error = xfs_bmap_longest_free_extent(pag, args->tp, blen);

	xfs_perag_rele(pag);

	if (error) {

		if (error != -EAGAIN)

					goto out_error;

			return error;

		*blen = 0;

	}

		}



	/*

	 * We are done if there's still enough contiguous free space to succeed.

	 */

	if (*blen >= args->maxlen)

			goto out_select;

	} else if (xfs_is_inode32(mp)) {

		xfs_agnumber_t	 rotorstep = xfs_rotorstep;

		agno = (mp->m_agfrotor / rotorstep) %

				mp->m_sb.sb_agcount;

		mp->m_agfrotor = (mp->m_agfrotor + 1) %

				 (mp->m_sb.sb_agcount * rotorstep);

	} else {

		agno = XFS_INO_TO_AGNO(mp, pip->i_ino);

	}

		return 0;



	/* Changing parent AG association now, so remove the existing one. */

	mru = xfs_mru_cache_remove(mp->m_filestream, pip->i_ino);

	if (mru) {

		struct xfs_fstrm_item *item =

			container_of(mru, struct xfs_fstrm_item, mru);

		agno = (item->ag + 1) % mp->m_sb.sb_agcount;

		*agno = (item->ag + 1) % mp->m_sb.sb_agcount;

		xfs_fstrm_free_func(mp, mru);

		return 0;

	}



out_default_agno:

	if (xfs_is_inode32(mp)) {

		xfs_agnumber_t	 rotorstep = xfs_rotorstep;

		*agno = (mp->m_agfrotor / rotorstep) %

				mp->m_sb.sb_agcount;

		mp->m_agfrotor = (mp->m_agfrotor + 1) %

				 (mp->m_sb.sb_agcount * rotorstep);

		return 0;

	}

	*agno = XFS_INO_TO_AGNO(mp, pip->i_ino);

	return 0;



}



/*

 * Search for an allocation group with a single extent large enough for

 * the request.  If one isn't found, then adjust the minimum allocation

 * size to the largest space found.

 */

int

xfs_filestream_select_ag(

	struct xfs_bmalloca	*ap,

	struct xfs_alloc_arg	*args,

	xfs_extlen_t		*blen)

{

	struct xfs_mount	*mp = ap->ip->i_mount;

	struct xfs_inode	*pip = NULL;

	xfs_agnumber_t		agno;

	int			flags = 0;

	int			error;



	args->total = ap->total;

	*blen = 0;



	pip = xfs_filestream_get_parent(ap->ip);

	if (!pip) {

		agno = 0;

		goto out_select;

	}



	error = xfs_filestream_select_ag_mru(ap, args, pip, &agno, blen);

	if (error || *blen >= args->maxlen)

		goto out_rele;



	ap->blkno = XFS_AGB_TO_FSB(args->mp, agno, 0);

	xfs_bmap_adjacent(ap);
@@ -347,8 +382,6 @@ xfs_filestream_select_ag( 


	*blen = ap->length;

	error = xfs_filestream_pick_ag(pip, &agno, flags, blen);

	if (error)

		goto out_error;

	if (agno == NULLAGNUMBER) {

		agno = 0;

		*blen = 0;
@@ -356,7 +389,7 @@ xfs_filestream_select_ag( 


out_select:

	ap->blkno = XFS_AGB_TO_FSB(mp, agno, 0);

out_error:

out_rele:

	xfs_irele(pip);

	return error;