Re: [PATCH] xfs: improve xfs_iext_destroy() by freeing extent indirection array directly

Jeff Liu
2013-09-20T14:38:41Z

On 09/20/2013 09:21 PM, Jeff Liu wrote:

> From: Jie Liu <jeff.liu@oracle.com>
>
> To free the incore file extents stores at the indirection array, we
> call the common routine xfs_iext_irec_remove() to remove a record
> from the array one at a time in reverse order, which will resize an
> extent indirection array repeatedly according to the array size.
>
> This is not often the case to make a file with thousands extent records
> stores at an indirection array, but above operation is inefficient and
> could result in memory fragments.
>
> This patch refine xfs_iext_destroy() by freeing the extent records from
> the indirection array directly in this case.
>
> Signed-off-by: Jie Liu <jeff.liu@oracle.com>
> ---
> fs/xfs/xfs_inode_fork.c | 7 +++++--
> 1 file changed, 5 insertions(+), 2 deletions(-)
>
> diff --git a/fs/xfs/xfs_inode_fork.c b/fs/xfs/xfs_inode_fork.c
> index 02f1083..ba70f98 100644
> --- a/fs/xfs/xfs_inode_fork.c
> +++ b/fs/xfs/xfs_inode_fork.c
> @@ -1525,9 +1525,12 @@ xfs_iext_destroy(
> int nlists;
>
> nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ;
> - for (erp_idx = nlists - 1; erp_idx >= 0 ; erp_idx--) {
> - xfs_iext_irec_remove(ifp, erp_idx);
> + for (erp_idex = 0; erp_idx < nlists; erp_idx++) {

Sorry, here is a typo, s/erp_idex/erp_idx/, will resend it.

> + xfs_ext_irec_t *erp = &ifp->if_u1.if_ext_irec[erp_idx];
> + if (erp->er_extbuf)
> + kmem_free(erp->er_extbuf);
> }
> + kmem_free(ifp->if_u1.if_ext_irec);
> ifp->if_flags &= ~XFS_IFEXTIREC;
> } else if (ifp->if_real_bytes) {
> kmem_free(ifp->if_u1.if_extents);