review [1 of 3]: lazy superblock counters - fix interaction with per-cpu incore counters

[David Chinner <dgc@xxxxxxx>]

We need to reinitialise the per-cpu superblock counters after
we have corrected them in the new recovery phase (summing hte AGF/AGI
counters.

-- 
Dave Chinner
Principal Engineer
SGI Australian Software Group

---
 fs/xfs/xfs_mount.c |   53 ++++++++++++++++++++++++++++++++---------------------
 1 file changed, 32 insertions(+), 21 deletions(-)

Index: 2.6.x-xfs-new/fs/xfs/xfs_mount.c
===================================================================
--- 2.6.x-xfs-new.orig/fs/xfs/xfs_mount.c       2007-04-19 13:46:42.536211213 
+1000
+++ 2.6.x-xfs-new/fs/xfs/xfs_mount.c    2007-04-19 13:47:41.272642686 +1000
@@ -676,6 +676,10 @@ xfs_initialize_perag_data(xfs_mount_t *m
        sbp->sb_icount = ialloc;
        sbp->sb_fdblocks = bfree + bfreelst + btree;
        XFS_SB_UNLOCK(mp, s);
+
+       /* Fixup the per-cpu counters as well. */
+       xfs_icsb_reinit_counters(mp);
+
        return 0;
 }
 
@@ -1022,6 +1026,34 @@ xfs_mountfs(
        }
 
        /*
+        * Now the log is mounted, we know if it was an unclean shutdown or
+        * not. If it was, with the first phase of recovery has completed, we
+        * have consistent AG blocks on disk. We have not recovered EFIs yet,
+        * but they are recovered transactionally in the second recovery phase
+        * later.
+        *
+        * Hence we can safely re-initialise incore superblock counters from
+        * the per-ag data. These may not be correct if the filesystem was not
+        * cleanly unmounted, so we need to wait for recovery to finish before
+        * doing this.
+        *
+        * If the filesystem was cleanly unmounted, then we can trust the
+        * values in the superblock to be correct and we don't need to do
+        * anything here.
+        *
+        * If we are currently making the filesystem, the initialisation will
+        * fail as the perag data is in an undefined state.
+        */
+
+       if (XFS_SB_VERSION_LAZYSBCOUNT(&mp->m_sb) &&
+           !XFS_LAST_UNMOUNT_WAS_CLEAN(mp) &&
+            !mp->m_sb.sb_inprogress) {
+               error = xfs_initialize_perag_data(mp, sbp->sb_agcount);
+               if (error) {
+                       goto error2;
+               }
+       }
+       /*
         * Get and sanity-check the root inode.
         * Save the pointer to it in the mount structure.
         */
@@ -1084,27 +1116,6 @@ xfs_mountfs(
                goto error4;
        }
 
-       /*
-        * Now recovery has completed, we can initialise incore
-        * superblock counters from the per-ag data. These may not
-        * be correct if the filesystem was not cleanly unmounted,
-        * so we need to wait for recovery to finish before doing this.
-        *
-        * If the filesystem was cleanly unmounted, then we can trust
-        * the values in the superblock to be correct and we don't need
-        * to do anything here.
-        *
-        * If we are currently making the filesystem, the initialisation
-        * will fail as the perag data is in an undefined state.
-        */
-       if (XFS_SB_VERSION_LAZYSBCOUNT(&mp->m_sb) &&
-           !XFS_LAST_UNMOUNT_WAS_CLEAN(mp) &&
-            !mp->m_sb.sb_inprogress) {
-               error = xfs_initialize_perag_data(mp, sbp->sb_agcount);
-               if (error) {
-                       goto error4;
-               }
-       }
 
        /*
         * Complete the quota initialisation, post-log-replay component.