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

Jeff Liu
2013-09-20T14:40:42Z

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_idx = 0; erp_idx < nlists; erp_idx++) {
+ 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);
-- 1.7.9.5