xfs: don't track firstrec/firstkey separately in xchk_btree

The btree scrubbing code checks that the records (or keys) that it finds
in a btree block are all in order by calling the btree cursor's
->recs_inorder function.  This of course makes no sense for the first
item in the block, so we switch that off with a separate variable in
struct xchk_btree.

Christoph helped me figure out that the variable is unnecessary, since
we just accessed bc_ptrs[level] and can compare that against zero.  Use
that, and save ourselves some memory space.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>

diff --git a/fs/xfs/scrub/btree.c b/fs/xfs/scrub/btree.c
index 26dcb46..d5e1ca5 100644 (file)
--- a/fs/xfs/scrub/btree.c
+++ b/fs/xfs/scrub/btree.c
@@ -141,9 +141,9 @@ xchk_btree_rec(
        trace_xchk_btree_rec(bs->sc, cur, 0);
 
        /* If this isn't the first record, are they in order? */
-       if (!bs->firstrec && !cur->bc_ops->recs_inorder(cur, &bs->lastrec, rec))
+       if (cur->bc_ptrs[0] > 1 &&
+           !cur->bc_ops->recs_inorder(cur, &bs->lastrec, rec))
                xchk_btree_set_corrupt(bs->sc, cur, 0);
-       bs->firstrec = false;
        memcpy(&bs->lastrec, rec, cur->bc_ops->rec_len);
 
        if (cur->bc_nlevels == 1)
@@ -188,10 +188,9 @@ xchk_btree_key(
        trace_xchk_btree_key(bs->sc, cur, level);
 
        /* If this isn't the first key, are they in order? */
-       if (!bs->firstkey[level] &&
+       if (cur->bc_ptrs[level] > 1 &&
            !cur->bc_ops->keys_inorder(cur, &bs->lastkey[level], key))
                xchk_btree_set_corrupt(bs->sc, cur, level);
-       bs->firstkey[level] = false;
        memcpy(&bs->lastkey[level], key, cur->bc_ops->key_len);
 
        if (level + 1 >= cur->bc_nlevels)
@@ -636,7 +635,6 @@ xchk_btree(
        struct xfs_buf                  *bp;
        struct check_owner              *co;
        struct check_owner              *n;
-       int                             i;
        int                             error = 0;
 
        /*
@@ -649,13 +647,10 @@ xchk_btree(
        bs->cur = cur;
        bs->scrub_rec = scrub_fn;
        bs->oinfo = oinfo;
-       bs->firstrec = true;
        bs->private = private;
        bs->sc = sc;
 
        /* Initialize scrub state */
-       for (i = 0; i < XFS_BTREE_MAXLEVELS; i++)
-               bs->firstkey[i] = true;
        INIT_LIST_HEAD(&bs->to_check);
 
        /* Don't try to check a tree with a height we can't handle. */

diff --git a/fs/xfs/scrub/btree.h b/fs/xfs/scrub/btree.h
index b7d2fc0..7671108 100644 (file)
--- a/fs/xfs/scrub/btree.h
+++ b/fs/xfs/scrub/btree.h
@@ -39,9 +39,7 @@ struct xchk_btree {
 
        /* internal scrub state */
        union xfs_btree_rec             lastrec;
-       bool                            firstrec;
        union xfs_btree_key             lastkey[XFS_BTREE_MAXLEVELS];
-       bool                            firstkey[XFS_BTREE_MAXLEVELS];
        struct list_head                to_check;
 };
 int xchk_btree(struct xfs_scrub *sc, struct xfs_btree_cur *cur,