xfs
[Top] [All Lists]

[PATCH v3 11/18] xfs: randomly do sparse inode allocations in DEBUG mode

To: xfs@xxxxxxxxxxx
Subject: [PATCH v3 11/18] xfs: randomly do sparse inode allocations in DEBUG mode
From: Brian Foster <bfoster@xxxxxxxxxx>
Date: Fri, 6 Feb 2015 14:52:58 -0500
Delivered-to: xfs@xxxxxxxxxxx
In-reply-to: <1423252385-3063-1-git-send-email-bfoster@xxxxxxxxxx>
References: <1423252385-3063-1-git-send-email-bfoster@xxxxxxxxxx>
Sparse inode allocations generally only occur when full inode chunk
allocation fails. This requires some level of filesystem space usage and
fragmentation.

For filesystems formatted with sparse inode chunks enabled, do random
sparse inode chunk allocs when compiled in DEBUG mode to increase test
coverage.

Signed-off-by: Brian Foster <bfoster@xxxxxxxxxx>
---
 fs/xfs/libxfs/xfs_ialloc.c | 19 +++++++++++++++++--
 1 file changed, 17 insertions(+), 2 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_ialloc.c b/fs/xfs/libxfs/xfs_ialloc.c
index 090d114..3e5d3eb 100644
--- a/fs/xfs/libxfs/xfs_ialloc.c
+++ b/fs/xfs/libxfs/xfs_ialloc.c
@@ -652,9 +652,18 @@ xfs_ialloc_ag_alloc(
 
        struct xfs_perag *pag;
 
+#ifdef DEBUG
+       int             do_sparse = 0;
+
+       /* randomly do sparse inode allocations */
+       if (xfs_sb_version_hassparseinodes(&tp->t_mountp->m_sb))
+               do_sparse = prandom_u32() & 1;
+#endif
+
        memset(&args, 0, sizeof(args));
        args.tp = tp;
        args.mp = tp->t_mountp;
+       args.fsbno = NULLFSBLOCK;
 
        /*
         * Locking will ensure that we don't have two callers in here
@@ -675,6 +684,10 @@ xfs_ialloc_ag_alloc(
        agno = be32_to_cpu(agi->agi_seqno);
        args.agbno = XFS_AGINO_TO_AGBNO(args.mp, newino) +
                     args.mp->m_ialloc_blks;
+#ifdef DEBUG
+       if (do_sparse)
+               goto sparse_alloc;
+#endif
        if (likely(newino != NULLAGINO &&
                  (args.agbno < be32_to_cpu(agi->agi_length)))) {
                args.fsbno = XFS_AGB_TO_FSB(args.mp, agno, args.agbno);
@@ -713,8 +726,7 @@ xfs_ialloc_ag_alloc(
                 * subsequent requests.
                 */
                args.minalignslop = 0;
-       } else
-               args.fsbno = NULLFSBLOCK;
+       }
 
        if (unlikely(args.fsbno == NULLFSBLOCK)) {
                /*
@@ -769,6 +781,9 @@ xfs_ialloc_ag_alloc(
         * Finally, try a sparse allocation if the filesystem supports it and
         * the sparse allocation length is smaller than a full chunk.
         */
+#ifdef DEBUG
+sparse_alloc:
+#endif
        if (xfs_sb_version_hassparseinodes(&args.mp->m_sb) &&
            args.mp->m_ialloc_min_blks < args.mp->m_ialloc_blks &&
            args.fsbno == NULLFSBLOCK) {
-- 
1.8.3.1

<Prev in Thread] Current Thread [Next in Thread>