[XFS] A change to inode chunk allocation to try allocating the new chunk

contiguous with the most recently allocated chunk.  On a striped
filesystem, this will fill a stripe unit with inodes before allocating new
inodes in another stripe unit.

SGI-PV: 951416
SGI-Modid: xfs-linux-melb:xfs-kern:208488a

Signed-off-by: Glen Overby <overby@sgi.com>
Signed-off-by: Nathan Scott <nathans@sgi.com>

1 files changed, 68 insertions, 40 deletions

diff --git a/fs/xfs/xfs_ialloc.c b/fs/xfs/xfs_ialloc.c
index 20c39a6e6a0c..4eeb856183b1 100644
--- a/fs/xfs/xfs_ialloc.c
+++ b/fs/xfs/xfs_ialloc.c
@@ -136,7 +136,7 @@ xfs_ialloc_ag_alloc(
         int             ninodes;        /* num inodes per buf */
         xfs_agino_t     thisino;        /* current inode number, for loop */
         int             version;        /* inode version number to use */
-        int             isaligned;      /* inode allocation at stripe unit */
+        int             isaligned = 0;  /* inode allocation at stripe unit */
                                         /* boundary */
 
         args.tp = tp;
@@ -152,47 +152,75 @@ xfs_ialloc_ag_alloc(
                 return XFS_ERROR(ENOSPC);
         args.minlen = args.maxlen = XFS_IALLOC_BLOCKS(args.mp);
         /*
-         * Set the alignment for the allocation.
-         * If stripe alignment is turned on then align at stripe unit
-         * boundary.
-         * If the cluster size is smaller than a filesystem block
-         * then we're doing I/O for inodes in filesystem block size pieces,
-         * so don't need alignment anyway.
-         */
-        isaligned = 0;
-        if (args.mp->m_sinoalign) {
-                ASSERT(!(args.mp->m_flags & XFS_MOUNT_NOALIGN));
-                args.alignment = args.mp->m_dalign;
-                isaligned = 1;
-        } else if (XFS_SB_VERSION_HASALIGN(&args.mp->m_sb) &&
-            args.mp->m_sb.sb_inoalignmt >=
-            XFS_B_TO_FSBT(args.mp, XFS_INODE_CLUSTER_SIZE(args.mp)))
-                args.alignment = args.mp->m_sb.sb_inoalignmt;
-        else
-                args.alignment = 1;
+         * First try to allocate inodes contiguous with the last-allocated
+         * chunk of inodes.  If the filesystem is striped, this will fill
+         * an entire stripe unit with inodes.
+         */
         agi = XFS_BUF_TO_AGI(agbp);
-        /*
-         * Need to figure out where to allocate the inode blocks.
-         * Ideally they should be spaced out through the a.g.
-         * For now, just allocate blocks up front.
-         */
-        args.agbno = be32_to_cpu(agi->agi_root);
-        args.fsbno = XFS_AGB_TO_FSB(args.mp, be32_to_cpu(agi->agi_seqno),
-                                    args.agbno);
-        /*
-         * Allocate a fixed-size extent of inodes.
-         */
-        args.type = XFS_ALLOCTYPE_NEAR_BNO;
-        args.mod = args.total = args.wasdel = args.isfl = args.userdata =
-                args.minalignslop = 0;
-        args.prod = 1;
-        /*
-         * Allow space for the inode btree to split.
-         */
-        args.minleft = XFS_IN_MAXLEVELS(args.mp) - 1;
-        if ((error = xfs_alloc_vextent(&args)))
-                return error;
+        newino = be32_to_cpu(agi->agi_newino);
+        if(likely(newino != NULLAGINO)) {
+                args.agbno = XFS_AGINO_TO_AGBNO(args.mp, newino) +
+                                XFS_IALLOC_BLOCKS(args.mp);
+                args.fsbno = XFS_AGB_TO_FSB(args.mp,
+                                be32_to_cpu(agi->agi_seqno), args.agbno);
+                args.type = XFS_ALLOCTYPE_THIS_BNO;
+                args.mod = args.total = args.wasdel = args.isfl =
+                        args.userdata = args.minalignslop = 0;
+                args.prod = 1;
+                args.alignment = 1;
+                /*
+                 * Allow space for the inode btree to split.
+                 */
+                args.minleft = XFS_IN_MAXLEVELS(args.mp) - 1;
+                if ((error = xfs_alloc_vextent(&args)))
+                        return error;
+        } else
+                args.fsbno = NULLFSBLOCK;
 
+        if (unlikely(args.fsbno == NULLFSBLOCK)) {
+                /*
+                 * Set the alignment for the allocation.
+                 * If stripe alignment is turned on then align at stripe unit
+                 * boundary.
+                 * If the cluster size is smaller than a filesystem block 
+                 * then we're doing I/O for inodes in filesystem block size 
+                 * pieces, so don't need alignment anyway.
+                 */
+                isaligned = 0;
+                if (args.mp->m_sinoalign) {
+                        ASSERT(!(args.mp->m_flags & XFS_MOUNT_NOALIGN));
+                        args.alignment = args.mp->m_dalign;
+                        isaligned = 1;
+                } else if (XFS_SB_VERSION_HASALIGN(&args.mp->m_sb) &&
+                           args.mp->m_sb.sb_inoalignmt >= 
+                           XFS_B_TO_FSBT(args.mp,
+                                XFS_INODE_CLUSTER_SIZE(args.mp)))
+                                args.alignment = args.mp->m_sb.sb_inoalignmt;
+                else
+                        args.alignment = 1;
+                /*
+                 * Need to figure out where to allocate the inode blocks.
+                 * Ideally they should be spaced out through the a.g.
+                 * For now, just allocate blocks up front.
+                 */
+                args.agbno = be32_to_cpu(agi->agi_root);
+                args.fsbno = XFS_AGB_TO_FSB(args.mp,
+                                be32_to_cpu(agi->agi_seqno), args.agbno);
+                /*
+                 * Allocate a fixed-size extent of inodes.
+                 */
+                args.type = XFS_ALLOCTYPE_NEAR_BNO;
+                args.mod = args.total = args.wasdel = args.isfl =
+                        args.userdata = args.minalignslop = 0;
+                args.prod = 1;
+                /*
+                 * Allow space for the inode btree to split.
+                 */
+                args.minleft = XFS_IN_MAXLEVELS(args.mp) - 1;
+                if ((error = xfs_alloc_vextent(&args)))
+                        return error;
+        }
+ 
         /*
          * If stripe alignment is turned on, then try again with cluster
          * alignment.