From 745b3f76d1c889d738a1c4537a3c491bc1ecac4d Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 17 Jul 2018 16:51:51 -0700 Subject: [PATCH] xfs: maintain a sequence count for inode fork manipulations Add a simple 32-bit unsigned integer as the sequence count for modifications to the extent list in the inode fork. This will be used to optimize away extent list lookups in the writeback code. Signed-off-by: Christoph Hellwig Reviewed-by: Carlos Maiolino Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong --- fs/xfs/libxfs/xfs_iext_tree.c | 6 ++++++ fs/xfs/libxfs/xfs_inode_fork.h | 1 + 2 files changed, 7 insertions(+) diff --git a/fs/xfs/libxfs/xfs_iext_tree.c b/fs/xfs/libxfs/xfs_iext_tree.c index b80c63faace2..8a7aea041ee1 100644 --- a/fs/xfs/libxfs/xfs_iext_tree.c +++ b/fs/xfs/libxfs/xfs_iext_tree.c @@ -624,6 +624,8 @@ xfs_iext_insert( struct xfs_iext_leaf *new = NULL; int nr_entries, i; + ifp->if_seq++; + if (ifp->if_height == 0) xfs_iext_alloc_root(ifp, cur); else if (ifp->if_height == 1) @@ -864,6 +866,8 @@ xfs_iext_remove( ASSERT(ifp->if_u1.if_root != NULL); ASSERT(xfs_iext_valid(ifp, cur)); + ifp->if_seq++; + nr_entries = xfs_iext_leaf_nr_entries(ifp, leaf, cur->pos) - 1; for (i = cur->pos; i < nr_entries; i++) leaf->recs[i] = leaf->recs[i + 1]; @@ -970,6 +974,8 @@ xfs_iext_update_extent( { struct xfs_ifork *ifp = xfs_iext_state_to_fork(ip, state); + ifp->if_seq++; + if (cur->pos == 0) { struct xfs_bmbt_irec old; diff --git a/fs/xfs/libxfs/xfs_inode_fork.h b/fs/xfs/libxfs/xfs_inode_fork.h index 1492143371f3..60361d2d74a1 100644 --- a/fs/xfs/libxfs/xfs_inode_fork.h +++ b/fs/xfs/libxfs/xfs_inode_fork.h @@ -14,6 +14,7 @@ struct xfs_dinode; */ struct xfs_ifork { int if_bytes; /* bytes in if_u1 */ + unsigned int if_seq; /* cow fork mod counter */ struct xfs_btree_block *if_broot; /* file's incore btree root */ short if_broot_bytes; /* bytes allocated for root */ unsigned char if_flags; /* per-fork flags */