[patch 23/27] fs: icache lock i_count

[npiggin@suse.de]

[-- Attachment #1: fs-inode_lock-scale-4.patch --]
[-- Type: text/plain, Size: 33238 bytes --]

Protect inode->i_count with i_lock, rather than having it atomic.
Next step should also be to move things together (eg. the refcount increment
into d_instantiate, which will remove a lock/unlock cycle on i_lock).
---
 arch/powerpc/platforms/cell/spufs/file.c |    2 -
 fs/affs/inode.c                          |    4 ++-
 fs/afs/dir.c                             |    4 ++-
 fs/anon_inodes.c                         |    4 ++-
 fs/bfs/dir.c                             |    4 ++-
 fs/block_dev.c                           |    8 +++++-
 fs/btrfs/inode.c                         |    4 ++-
 fs/coda/dir.c                            |    4 ++-
 fs/exofs/inode.c                         |   12 +++++++---
 fs/exofs/namei.c                         |    4 ++-
 fs/ext2/namei.c                          |    4 ++-
 fs/ext3/ialloc.c                         |    4 +--
 fs/ext3/namei.c                          |    4 ++-
 fs/ext4/ialloc.c                         |    4 +--
 fs/ext4/namei.c                          |    4 ++-
 fs/fs-writeback.c                        |    4 +--
 fs/gfs2/ops_inode.c                      |    4 ++-
 fs/hfsplus/dir.c                         |    4 ++-
 fs/hpfs/inode.c                          |    2 -
 fs/inode.c                               |   37 ++++++++++++++++++++-----------
 fs/jffs2/dir.c                           |    8 +++++-
 fs/jfs/jfs_txnmgr.c                      |    4 ++-
 fs/jfs/namei.c                           |    4 ++-
 fs/libfs.c                               |    4 ++-
 fs/locks.c                               |    3 --
 fs/minix/namei.c                         |    4 ++-
 fs/namei.c                               |    7 ++++-
 fs/nfs/dir.c                             |    4 ++-
 fs/nfs/getroot.c                         |    4 ++-
 fs/nfs/inode.c                           |    4 +--
 fs/nilfs2/mdt.c                          |    2 -
 fs/nilfs2/namei.c                        |    4 ++-
 fs/notify/inotify/inotify.c              |   28 +++++++++++++----------
 fs/ocfs2/namei.c                         |    4 ++-
 fs/reiserfs/file.c                       |    4 +--
 fs/reiserfs/namei.c                      |    4 ++-
 fs/reiserfs/stree.c                      |    2 -
 fs/sysv/namei.c                          |    4 ++-
 fs/ubifs/dir.c                           |    4 ++-
 fs/ubifs/super.c                         |    2 -
 fs/udf/namei.c                           |    4 ++-
 fs/ufs/namei.c                           |    4 ++-
 fs/xfs/linux-2.6/xfs_iops.c              |    4 ++-
 fs/xfs/xfs_iget.c                        |    2 -
 fs/xfs/xfs_inode.h                       |    6 +++--
 include/linux/fs.h                       |    2 -
 ipc/mqueue.c                             |    7 ++++-
 kernel/futex.c                           |    4 ++-
 mm/shmem.c                               |    4 ++-
 49 files changed, 177 insertions(+), 85 deletions(-)

Index: linux-2.6/arch/powerpc/platforms/cell/spufs/file.c
===================================================================
--- linux-2.6.orig/arch/powerpc/platforms/cell/spufs/file.c
+++ linux-2.6/arch/powerpc/platforms/cell/spufs/file.c
@@ -1548,7 +1548,7 @@ static int spufs_mfc_open(struct inode *
 	if (ctx->owner != current->mm)
 		return -EINVAL;
 
-	if (atomic_read(&inode->i_count) != 1)
+	if (inode->i_count != 1)
 		return -EBUSY;
 
 	mutex_lock(&ctx->mapping_lock);
Index: linux-2.6/fs/affs/inode.c
===================================================================
--- linux-2.6.orig/fs/affs/inode.c
+++ linux-2.6/fs/affs/inode.c
@@ -379,7 +379,9 @@ affs_add_entry(struct inode *dir, struct
 		affs_adjust_checksum(inode_bh, block - be32_to_cpu(chain));
 		mark_buffer_dirty_inode(inode_bh, inode);
 		inode->i_nlink = 2;
-		atomic_inc(&inode->i_count);
+		spin_lock(&inode->i_lock);
+		inode->i_count++;
+		spin_unlock(&inode->i_lock);
 	}
 	affs_fix_checksum(sb, bh);
 	mark_buffer_dirty_inode(bh, inode);
Index: linux-2.6/fs/afs/dir.c
===================================================================
--- linux-2.6.orig/fs/afs/dir.c
+++ linux-2.6/fs/afs/dir.c
@@ -1007,7 +1007,9 @@ static int afs_link(struct dentry *from,
 	if (ret < 0)
 		goto link_error;
 
-	atomic_inc(&vnode->vfs_inode.i_count);
+	spin_lock(&vnode->vfs_inode.i_lock);
+	vnode->vfs_inode.i_count++;
+	spin_unlock(&vnode->vfs_inode.i_lock);
 	d_instantiate(dentry, &vnode->vfs_inode);
 	key_put(key);
 	_leave(" = 0");
Index: linux-2.6/fs/anon_inodes.c
===================================================================
--- linux-2.6.orig/fs/anon_inodes.c
+++ linux-2.6/fs/anon_inodes.c
@@ -104,7 +104,9 @@ int anon_inode_getfd(const char *name, c
 	 * so we can avoid doing an igrab() and we can use an open-coded
 	 * atomic_inc().
 	 */
-	atomic_inc(&anon_inode_inode->i_count);
+	spin_lock(&anon_inode_inode->i_lock);
+	anon_inode_inode->i_count++;
+	spin_unlock(&anon_inode_inode->i_lock);
 
 	dentry->d_op = &anon_inodefs_dentry_operations;
 	/* Do not publish this dentry inside the global dentry hash table */
Index: linux-2.6/fs/block_dev.c
===================================================================
--- linux-2.6.orig/fs/block_dev.c
+++ linux-2.6/fs/block_dev.c
@@ -579,7 +579,9 @@ static struct block_device *bd_acquire(s
 	spin_lock(&bdev_lock);
 	bdev = inode->i_bdev;
 	if (bdev) {
-		atomic_inc(&bdev->bd_inode->i_count);
+		spin_lock(&inode->i_lock);
+		bdev->bd_inode->i_count++;
+		spin_unlock(&inode->i_lock);
 		spin_unlock(&bdev_lock);
 		return bdev;
 	}
@@ -595,7 +597,9 @@ static struct block_device *bd_acquire(s
 			 * So, we can access it via ->i_mapping always
 			 * without igrab().
 			 */
-			atomic_inc(&bdev->bd_inode->i_count);
+			spin_lock(&inode->i_lock);
+			bdev->bd_inode->i_count++;
+			spin_unlock(&inode->i_lock);
 			inode->i_bdev = bdev;
 			inode->i_mapping = bdev->bd_inode->i_mapping;
 			list_add(&inode->i_devices, &bdev->bd_inodes);
Index: linux-2.6/fs/ext2/namei.c
===================================================================
--- linux-2.6.orig/fs/ext2/namei.c
+++ linux-2.6/fs/ext2/namei.c
@@ -188,7 +188,9 @@ static int ext2_link (struct dentry * ol
 
 	inode->i_ctime = CURRENT_TIME_SEC;
 	inode_inc_link_count(inode);
-	atomic_inc(&inode->i_count);
+	spin_lock(&inode->i_lock);
+	inode->i_count++;
+	spin_unlock(&inode->i_lock);
 
 	err = ext2_add_link(dentry, inode);
 	if (!err) {
Index: linux-2.6/fs/ext3/ialloc.c
===================================================================
--- linux-2.6.orig/fs/ext3/ialloc.c
+++ linux-2.6/fs/ext3/ialloc.c
@@ -100,9 +100,9 @@ void ext3_free_inode (handle_t *handle,
 	struct ext3_sb_info *sbi;
 	int fatal = 0, err;
 
-	if (atomic_read(&inode->i_count) > 1) {
+	if (inode->i_count > 1) {
 		printk ("ext3_free_inode: inode has count=%d\n",
-					atomic_read(&inode->i_count));
+					inode->i_count);
 		return;
 	}
 	if (inode->i_nlink) {
Index: linux-2.6/fs/ext3/namei.c
===================================================================
--- linux-2.6.orig/fs/ext3/namei.c
+++ linux-2.6/fs/ext3/namei.c
@@ -2244,7 +2244,9 @@ retry:
 
 	inode->i_ctime = CURRENT_TIME_SEC;
 	inc_nlink(inode);
-	atomic_inc(&inode->i_count);
+	spin_lock(&inode->i_lock);
+	inode->i_count++;
+	spin_unlock(&inode->i_lock);
 
 	err = ext3_add_entry(handle, dentry, inode);
 	if (!err) {
Index: linux-2.6/fs/fs-writeback.c
===================================================================
--- linux-2.6.orig/fs/fs-writeback.c
+++ linux-2.6/fs/fs-writeback.c
@@ -373,7 +373,7 @@ __sync_single_inode(struct inode *inode,
 			 * the pages.
 			 */
 			redirty_tail(inode);
-		} else if (atomic_read(&inode->i_count)) {
+		} else if (inode->i_count) {
 			/*
 			 * The inode is clean, inuse
 			 */
@@ -399,7 +399,7 @@ __writeback_single_inode(struct inode *i
 {
 	wait_queue_head_t *wqh;
 
-	if (!atomic_read(&inode->i_count))
+	if (!inode->i_count)
 		WARN_ON(!(inode->i_state & (I_WILL_FREE|I_FREEING)));
 	else
 		WARN_ON(inode->i_state & I_WILL_FREE);
Index: linux-2.6/fs/inode.c
===================================================================
--- linux-2.6.orig/fs/inode.c
+++ linux-2.6/fs/inode.c
@@ -131,7 +131,7 @@ struct inode *inode_init_always(struct s
 	inode->i_sb = sb;
 	inode->i_blkbits = sb->s_blocksize_bits;
 	inode->i_flags = 0;
-	atomic_set(&inode->i_count, 1);
+	inode->i_count = 1;
 	inode->i_op = &empty_iops;
 	inode->i_fop = &empty_fops;
 	inode->i_nlink = 1;
@@ -270,11 +270,10 @@ static void init_once(void *foo)
 void __iget(struct inode * inode)
 {
 	assert_spin_locked(&inode->i_lock);
-	if (atomic_read(&inode->i_count)) {
-		atomic_inc(&inode->i_count);
+	inode->i_count++;
+	if (inode->i_count > 1)
 		return;
-	}
-	atomic_inc(&inode->i_count);
+
 	if (!(inode->i_state & (I_DIRTY|I_SYNC)))
 		list_move(&inode->i_list, &inode_in_use);
 	inodes_stat.nr_unused--;
@@ -380,7 +379,7 @@ static int invalidate_list(struct list_h
 			continue;
 		}
 		invalidate_inode_buffers(inode);
-		if (!atomic_read(&inode->i_count)) {
+		if (!inode->i_count) {
 			list_move(&inode->i_list, dispose);
 			WARN_ON(inode->i_state & I_NEW);
 			inode->i_state |= I_FREEING;
@@ -431,7 +430,7 @@ static int can_unuse(struct inode *inode
 		return 0;
 	if (inode_has_buffers(inode))
 		return 0;
-	if (atomic_read(&inode->i_count))
+	if (inode->i_count)
 		return 0;
 	if (inode->i_data.nrpages)
 		return 0;
@@ -469,7 +468,7 @@ static void prune_icache(int nr_to_scan)
 		inode = list_entry(inode_unused.prev, struct inode, i_list);
 
 		spin_lock(&inode->i_lock);
-		if (inode->i_state || atomic_read(&inode->i_count)) {
+		if (inode->i_state || inode->i_count) {
 			list_move(&inode->i_list, &inode_unused);
 			spin_unlock(&inode->i_lock);
 			continue;
@@ -1222,8 +1221,6 @@ void generic_delete_inode(struct inode *
 {
 	const struct super_operations *op = inode->i_sb->s_op;
 
-	spin_lock(&sb_inode_list_lock);
-	spin_lock(&inode->i_lock);
 	list_del_init(&inode->i_list);
 	list_del_init(&inode->i_sb_list);
 	spin_unlock(&sb_inode_list_lock);
@@ -1264,8 +1261,6 @@ static void generic_forget_inode(struct
 {
 	struct super_block *sb = inode->i_sb;
 
-	spin_lock(&sb_inode_list_lock);
-	spin_lock(&inode->i_lock);
 	if (!hlist_unhashed(&inode->i_hash)) {
 		if (!(inode->i_state & (I_DIRTY|I_SYNC)))
 			list_move(&inode->i_list, &inode_unused);
@@ -1357,8 +1352,24 @@ void iput(struct inode *inode)
 	if (inode) {
 		BUG_ON(inode->i_state == I_CLEAR);
 
-		if (atomic_dec_and_lock(&inode->i_count, &inode_lock))
+retry:
+		spin_lock(&inode->i_lock);
+		if (inode->i_count == 1) {
+			if (!spin_trylock(&inode_lock)) {
+				spin_unlock(&inode->i_lock);
+				goto retry;
+			}
+			if (!spin_trylock(&sb_inode_list_lock)) {
+				spin_unlock(&inode_lock);
+				spin_unlock(&inode->i_lock);
+				goto retry;
+			}
+			inode->i_count--;
 			iput_final(inode);
+		} else {
+			inode->i_count--;
+			spin_unlock(&inode->i_lock);
+		}
 	}
 }
 
Index: linux-2.6/fs/libfs.c
===================================================================
--- linux-2.6.orig/fs/libfs.c
+++ linux-2.6/fs/libfs.c
@@ -278,7 +278,9 @@ int simple_link(struct dentry *old_dentr
 
 	inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME;
 	inc_nlink(inode);
-	atomic_inc(&inode->i_count);
+	spin_lock(&inode->i_lock);
+	inode->i_count++;
+	spin_unlock(&inode->i_lock);
 	dget(dentry);
 	d_instantiate(dentry, inode);
 	return 0;
Index: linux-2.6/fs/locks.c
===================================================================
--- linux-2.6.orig/fs/locks.c
+++ linux-2.6/fs/locks.c
@@ -1373,8 +1373,7 @@ int generic_setlease(struct file *filp,
 		if ((arg == F_RDLCK) && (atomic_read(&inode->i_writecount) > 0))
 			goto out;
 		if ((arg == F_WRLCK)
-		    && (dentry->d_count > 1
-			|| (atomic_read(&inode->i_count) > 1)))
+		    && (dentry->d_count > 1 || inode->i_count > 1))
 			goto out;
 	}
 
Index: linux-2.6/fs/namei.c
===================================================================
--- linux-2.6.orig/fs/namei.c
+++ linux-2.6/fs/namei.c
@@ -2267,8 +2267,11 @@ static long do_unlinkat(int dfd, const c
 		if (nd.last.name[nd.last.len])
 			goto slashes;
 		inode = dentry->d_inode;
-		if (inode)
-			atomic_inc(&inode->i_count);
+		if (inode) {
+			spin_lock(&inode->i_lock);
+			inode->i_count++;
+			spin_unlock(&inode->i_lock);
+		}
 		error = mnt_want_write(nd.path.mnt);
 		if (error)
 			goto exit2;
Index: linux-2.6/fs/nfs/dir.c
===================================================================
--- linux-2.6.orig/fs/nfs/dir.c
+++ linux-2.6/fs/nfs/dir.c
@@ -1537,7 +1537,9 @@ nfs_link(struct dentry *old_dentry, stru
 	d_drop(dentry);
 	error = NFS_PROTO(dir)->link(inode, dir, &dentry->d_name);
 	if (error == 0) {
-		atomic_inc(&inode->i_count);
+		spin_lock(&inode->i_lock);
+		inode->i_count++;
+		spin_unlock(&inode->i_lock);
 		d_add(dentry, inode);
 	}
 	return error;
Index: linux-2.6/fs/nfs/getroot.c
===================================================================
--- linux-2.6.orig/fs/nfs/getroot.c
+++ linux-2.6/fs/nfs/getroot.c
@@ -56,7 +56,9 @@ static int nfs_superblock_set_dummy_root
 			return -ENOMEM;
 		}
 		/* Circumvent igrab(): we know the inode is not being freed */
-		atomic_inc(&inode->i_count);
+		spin_lock(&inode->i_lock);
+		inode->i_count++;
+		spin_unlock(&inode->i_lock);
 		/*
 		 * Ensure that this dentry is invisible to d_find_alias().
 		 * Otherwise, it may be spliced into the tree by
Index: linux-2.6/fs/notify/inotify/inotify.c
===================================================================
--- linux-2.6.orig/fs/notify/inotify/inotify.c
+++ linux-2.6/fs/notify/inotify/inotify.c
@@ -405,23 +405,28 @@ void inotify_unmount_inodes(struct list_
 		 * evict all inodes with zero i_count from icache which is
 		 * unnecessarily violent and may in fact be illegal to do.
 		 */
-		if (!atomic_read(&inode->i_count))
+		if (!inode->i_count)
 			continue;
 
 		need_iput_tmp = need_iput;
 		need_iput = NULL;
 		/* In case inotify_remove_watch_locked() drops a reference. */
-		if (inode != need_iput_tmp)
+		if (inode != need_iput_tmp) {
+			spin_lock(&inode->i_lock);
 			__iget(inode);
-		else
+			spin_unlock(&inode->i_lock);
+		} else
 			need_iput_tmp = NULL;
 		/* In case the dropping of a reference would nuke next_i. */
-		if ((&next_i->i_sb_list != list) &&
-				atomic_read(&next_i->i_count) &&
-				!(next_i->i_state & (I_CLEAR | I_FREEING |
-					I_WILL_FREE))) {
-			__iget(next_i);
-			need_iput = next_i;
+		if (&next_i->i_sb_list != list) {
+			spin_lock(&next_i->i_lock);
+			if (next_i->i_count &&
+				!(next_i->i_state &
+					(I_CLEAR|I_FREEING|I_WILL_FREE))) {
+				__iget(next_i);
+				need_iput = next_i;
+			}
+			spin_unlock(&next_i->i_lock);
 		}
 
 		/*
@@ -440,11 +445,10 @@ void inotify_unmount_inodes(struct list_
 		mutex_lock(&inode->inotify_mutex);
 		watches = &inode->inotify_watches;
 		list_for_each_entry_safe(watch, next_w, watches, i_list) {
-			struct inotify_handle *ih= watch->ih;
+			struct inotify_handle *ih = watch->ih;
 			get_inotify_watch(watch);
 			mutex_lock(&ih->mutex);
-			ih->in_ops->handle_event(watch, watch->wd, IN_UNMOUNT, 0,
-						 NULL, NULL);
+			ih->in_ops->handle_event(watch, watch->wd, IN_UNMOUNT, 0, NULL, NULL);
 			inotify_remove_watch_locked(ih, watch);
 			mutex_unlock(&ih->mutex);
 			put_inotify_watch(watch);
Index: linux-2.6/fs/xfs/linux-2.6/xfs_iops.c
===================================================================
--- linux-2.6.orig/fs/xfs/linux-2.6/xfs_iops.c
+++ linux-2.6/fs/xfs/linux-2.6/xfs_iops.c
@@ -362,7 +362,9 @@ xfs_vn_link(
 	if (unlikely(error))
 		return -error;
 
-	atomic_inc(&inode->i_count);
+	spin_lock(&inode->i_lock);
+	inode->i_count++;
+	spin_unlock(&inode->i_lock);
 	d_instantiate(dentry, inode);
 	return 0;
 }
Index: linux-2.6/fs/xfs/xfs_iget.c
===================================================================
--- linux-2.6.orig/fs/xfs/xfs_iget.c
+++ linux-2.6/fs/xfs/xfs_iget.c
@@ -822,7 +822,7 @@ xfs_isilocked(
 /*  0 */		(void *)(__psint_t)(vk),		\
 /*  1 */		(void *)(s),				\
 /*  2 */		(void *)(__psint_t) line,		\
-/*  3 */		(void *)(__psint_t)atomic_read(&VFS_I(ip)->i_count), \
+/*  3 */		(void *)(__psint_t)&VFS_I(ip)->i_count,	\
 /*  4 */		(void *)(ra),				\
 /*  5 */		NULL,					\
 /*  6 */		(void *)(__psint_t)current_cpu(),	\
Index: linux-2.6/fs/xfs/xfs_inode.h
===================================================================
--- linux-2.6.orig/fs/xfs/xfs_inode.h
+++ linux-2.6/fs/xfs/xfs_inode.h
@@ -561,8 +561,10 @@ extern void xfs_itrace_rele(struct xfs_i
 
 #define IHOLD(ip) \
 do { \
-	ASSERT(atomic_read(&VFS_I(ip)->i_count) > 0) ; \
-	atomic_inc(&(VFS_I(ip)->i_count)); \
+	spin_lock(&VFS_I(ip)->i_lock);		\
+	ASSERT(&VFS_I(ip)->i_count > 0);	\
+	VFS_I(ip)->i_count++;			\
+	spin_unlock(&VFS_I(ip)->i_lock);	\
 	xfs_itrace_hold((ip), __FILE__, __LINE__, (inst_t *)__return_address); \
 } while (0)
 
Index: linux-2.6/include/linux/fs.h
===================================================================
--- linux-2.6.orig/include/linux/fs.h
+++ linux-2.6/include/linux/fs.h
@@ -716,7 +716,7 @@ struct inode {
 	struct list_head	i_sb_list;
 	struct list_head	i_dentry;
 	unsigned long		i_ino;
-	atomic_t		i_count;
+	unsigned int		i_count;
 	unsigned int		i_nlink;
 	uid_t			i_uid;
 	gid_t			i_gid;
Index: linux-2.6/ipc/mqueue.c
===================================================================
--- linux-2.6.orig/ipc/mqueue.c
+++ linux-2.6/ipc/mqueue.c
@@ -777,8 +777,11 @@ SYSCALL_DEFINE1(mq_unlink, const char __
 	}
 
 	inode = dentry->d_inode;
-	if (inode)
-		atomic_inc(&inode->i_count);
+	if (inode) {
+		spin_lock(&inode->i_lock);
+		inode->i_count++;
+		spin_unlock(&inode->i_lock);
+	}
 	err = mnt_want_write(ipc_ns->mq_mnt);
 	if (err)
 		goto out_err;
Index: linux-2.6/kernel/futex.c
===================================================================
--- linux-2.6.orig/kernel/futex.c
+++ linux-2.6/kernel/futex.c
@@ -158,7 +158,9 @@ static void get_futex_key_refs(union fut
 
 	switch (key->both.offset & (FUT_OFF_INODE|FUT_OFF_MMSHARED)) {
 	case FUT_OFF_INODE:
-		atomic_inc(&key->shared.inode->i_count);
+		spin_lock(&key->shared.inode->i_lock);
+		key->shared.inode->i_count++;
+		spin_unlock(&key->shared.inode->i_lock);
 		break;
 	case FUT_OFF_MMSHARED:
 		atomic_inc(&key->private.mm->mm_count);
Index: linux-2.6/mm/shmem.c
===================================================================
--- linux-2.6.orig/mm/shmem.c
+++ linux-2.6/mm/shmem.c
@@ -1862,7 +1862,9 @@ static int shmem_link(struct dentry *old
 	dir->i_size += BOGO_DIRENT_SIZE;
 	inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME;
 	inc_nlink(inode);
-	atomic_inc(&inode->i_count);	/* New dentry reference */
+	spin_lock(&inode->i_lock);
+	inode->i_count++;	/* New dentry reference */
+	spin_unlock(&inode->i_lock);
 	dget(dentry);		/* Extra pinning count for the created dentry */
 	d_instantiate(dentry, inode);
 out:
Index: linux-2.6/fs/bfs/dir.c
===================================================================
--- linux-2.6.orig/fs/bfs/dir.c
+++ linux-2.6/fs/bfs/dir.c
@@ -179,7 +179,9 @@ static int bfs_link(struct dentry *old,
 	inc_nlink(inode);
 	inode->i_ctime = CURRENT_TIME_SEC;
 	mark_inode_dirty(inode);
-	atomic_inc(&inode->i_count);
+	spin_lock(&inode->i_lock);
+	inode->i_count++;
+	spin_unlock(&inode->i_lock);
 	d_instantiate(new, inode);
 	mutex_unlock(&info->bfs_lock);
 	return 0;
Index: linux-2.6/fs/btrfs/inode.c
===================================================================
--- linux-2.6.orig/fs/btrfs/inode.c
+++ linux-2.6/fs/btrfs/inode.c
@@ -3786,7 +3786,9 @@ static int btrfs_link(struct dentry *old
 	trans = btrfs_start_transaction(root, 1);
 
 	btrfs_set_trans_block_group(trans, dir);
-	atomic_inc(&inode->i_count);
+	spin_lock(&inode->i_lock);
+	inode->i_count++;
+	spin_unlock(&inode->i_lock);
 
 	err = btrfs_add_nondir(trans, dentry, inode, 1, index);
 
Index: linux-2.6/fs/coda/dir.c
===================================================================
--- linux-2.6.orig/fs/coda/dir.c
+++ linux-2.6/fs/coda/dir.c
@@ -302,7 +302,9 @@ static int coda_link(struct dentry *sour
 	}
 
 	coda_dir_update_mtime(dir_inode);
-	atomic_inc(&inode->i_count);
+	spin_lock(&inode->i_lock);
+	inode->i_count++;
+	spin_unlock(&inode->i_lock);
 	d_instantiate(de, inode);
 	inc_nlink(inode);
 
Index: linux-2.6/fs/exofs/inode.c
===================================================================
--- linux-2.6.orig/fs/exofs/inode.c
+++ linux-2.6/fs/exofs/inode.c
@@ -1037,7 +1037,9 @@ static void create_done(struct osd_reque
 	} else
 		set_obj_created(oi);
 
-	atomic_dec(&inode->i_count);
+	spin_lock(&inode->i_lock);
+	inode->i_count--;
+	spin_unlock(&inode->i_lock);
 	wake_up(&oi->i_wq);
 }
 
@@ -1103,11 +1105,15 @@ struct inode *exofs_new_inode(struct ino
 	/* increment the refcount so that the inode will still be around when we
 	 * reach the callback
 	 */
-	atomic_inc(&inode->i_count);
+	spin_lock(&inode->i_lock);
+	inode->i_count++;
+	spin_unlock(&inode->i_lock);
 
 	ret = exofs_async_op(or, create_done, inode, oi->i_cred);
 	if (ret) {
-		atomic_dec(&inode->i_count);
+		spin_lock(&inode->i_lock);
+		inode->i_count--;
+		spin_unlock(&inode->i_lock);
 		osd_end_request(or);
 		return ERR_PTR(-EIO);
 	}
Index: linux-2.6/fs/exofs/namei.c
===================================================================
--- linux-2.6.orig/fs/exofs/namei.c
+++ linux-2.6/fs/exofs/namei.c
@@ -155,7 +155,9 @@ static int exofs_link(struct dentry *old
 
 	inode->i_ctime = CURRENT_TIME;
 	inode_inc_link_count(inode);
-	atomic_inc(&inode->i_count);
+	spin_lock(&inode->i_lock);
+	inode->i_count++;
+	spin_unlock(&inode->i_lock);
 
 	return exofs_add_nondir(dentry, inode);
 }
Index: linux-2.6/fs/ext4/ialloc.c
===================================================================
--- linux-2.6.orig/fs/ext4/ialloc.c
+++ linux-2.6/fs/ext4/ialloc.c
@@ -190,9 +190,9 @@ void ext4_free_inode(handle_t *handle, s
 	struct ext4_sb_info *sbi;
 	int fatal = 0, err, count, cleared;
 
-	if (atomic_read(&inode->i_count) > 1) {
+	if (inode->i_count > 1) {
 		printk(KERN_ERR "ext4_free_inode: inode has count=%d\n",
-		       atomic_read(&inode->i_count));
+		       inode->i_count);
 		return;
 	}
 	if (inode->i_nlink) {
Index: linux-2.6/fs/ext4/namei.c
===================================================================
--- linux-2.6.orig/fs/ext4/namei.c
+++ linux-2.6/fs/ext4/namei.c
@@ -2327,7 +2327,9 @@ retry:
 
 	inode->i_ctime = ext4_current_time(inode);
 	ext4_inc_count(handle, inode);
-	atomic_inc(&inode->i_count);
+	spin_lock(&inode->i_lock);
+	inode->i_count++;
+	spin_unlock(&inode->i_lock);
 
 	err = ext4_add_entry(handle, dentry, inode);
 	if (!err) {
Index: linux-2.6/fs/gfs2/ops_inode.c
===================================================================
--- linux-2.6.orig/fs/gfs2/ops_inode.c
+++ linux-2.6/fs/gfs2/ops_inode.c
@@ -255,7 +255,9 @@ out_parent:
 	gfs2_holder_uninit(ghs);
 	gfs2_holder_uninit(ghs + 1);
 	if (!error) {
-		atomic_inc(&inode->i_count);
+		spin_lock(&inode->i_lock);
+		inode->i_count++;
+		spin_unlock(&inode->i_lock);
 		d_instantiate(dentry, inode);
 		mark_inode_dirty(inode);
 	}
Index: linux-2.6/fs/hfsplus/dir.c
===================================================================
--- linux-2.6.orig/fs/hfsplus/dir.c
+++ linux-2.6/fs/hfsplus/dir.c
@@ -301,7 +301,9 @@ static int hfsplus_link(struct dentry *s
 
 	inc_nlink(inode);
 	hfsplus_instantiate(dst_dentry, inode, cnid);
-	atomic_inc(&inode->i_count);
+	spin_lock(&inode->i_lock);
+	inode->i_count++;
+	spin_unlock(&inode->i_lock);
 	inode->i_ctime = CURRENT_TIME_SEC;
 	mark_inode_dirty(inode);
 	HFSPLUS_SB(sb).file_count++;
Index: linux-2.6/fs/hpfs/inode.c
===================================================================
--- linux-2.6.orig/fs/hpfs/inode.c
+++ linux-2.6/fs/hpfs/inode.c
@@ -181,7 +181,7 @@ void hpfs_write_inode(struct inode *i)
 	struct hpfs_inode_info *hpfs_inode = hpfs_i(i);
 	struct inode *parent;
 	if (i->i_ino == hpfs_sb(i->i_sb)->sb_root) return;
-	if (hpfs_inode->i_rddir_off && !atomic_read(&i->i_count)) {
+	if (hpfs_inode->i_rddir_off && !i->i_count) {
 		if (*hpfs_inode->i_rddir_off) printk("HPFS: write_inode: some position still there\n");
 		kfree(hpfs_inode->i_rddir_off);
 		hpfs_inode->i_rddir_off = NULL;
Index: linux-2.6/fs/jffs2/dir.c
===================================================================
--- linux-2.6.orig/fs/jffs2/dir.c
+++ linux-2.6/fs/jffs2/dir.c
@@ -287,7 +287,9 @@ static int jffs2_link (struct dentry *ol
 		mutex_unlock(&f->sem);
 		d_instantiate(dentry, old_dentry->d_inode);
 		dir_i->i_mtime = dir_i->i_ctime = ITIME(now);
-		atomic_inc(&old_dentry->d_inode->i_count);
+		spin_lock(&old_dentry->d_inode->i_lock);
+		old_dentry->d_inode->i_count++;
+		spin_unlock(&old_dentry->d_inode->i_lock);
 	}
 	return ret;
 }
@@ -866,7 +868,9 @@ static int jffs2_rename (struct inode *o
 		printk(KERN_NOTICE "jffs2_rename(): Link succeeded, unlink failed (err %d). You now have a hard link\n", ret);
 		/* Might as well let the VFS know */
 		d_instantiate(new_dentry, old_dentry->d_inode);
-		atomic_inc(&old_dentry->d_inode->i_count);
+		spin_lock(&old_dentry->d_inode->i_lock);
+		old_dentry->d_inode->i_count++;
+		spin_unlock(&old_dentry->d_inode->i_lock);
 		new_dir_i->i_mtime = new_dir_i->i_ctime = ITIME(now);
 		return ret;
 	}
Index: linux-2.6/fs/jfs/jfs_txnmgr.c
===================================================================
--- linux-2.6.orig/fs/jfs/jfs_txnmgr.c
+++ linux-2.6/fs/jfs/jfs_txnmgr.c
@@ -1279,7 +1279,9 @@ int txCommit(tid_t tid,		/* transaction
 	 * lazy commit thread finishes processing
 	 */
 	if (tblk->xflag & COMMIT_DELETE) {
-		atomic_inc(&tblk->u.ip->i_count);
+		spin_lock(&tblk->u.ip->i_lock);
+		tblk->u.ip->i_count++;
+		spin_unlock(&tblk->u.ip->i_lock);
 		/*
 		 * Avoid a rare deadlock
 		 *
Index: linux-2.6/fs/jfs/namei.c
===================================================================
--- linux-2.6.orig/fs/jfs/namei.c
+++ linux-2.6/fs/jfs/namei.c
@@ -831,7 +831,9 @@ static int jfs_link(struct dentry *old_d
 	ip->i_ctime = CURRENT_TIME;
 	dir->i_ctime = dir->i_mtime = CURRENT_TIME;
 	mark_inode_dirty(dir);
-	atomic_inc(&ip->i_count);
+	spin_lock(&ip->i_lock);
+	ip->i_count++;
+	spin_unlock(&ip->i_lock);
 
 	iplist[0] = ip;
 	iplist[1] = dir;
Index: linux-2.6/fs/minix/namei.c
===================================================================
--- linux-2.6.orig/fs/minix/namei.c
+++ linux-2.6/fs/minix/namei.c
@@ -103,7 +103,9 @@ static int minix_link(struct dentry * ol
 
 	inode->i_ctime = CURRENT_TIME_SEC;
 	inode_inc_link_count(inode);
-	atomic_inc(&inode->i_count);
+	spin_lock(&inode->i_lock);
+	inode->i_count++;
+	spin_unlock(&inode->i_lock);
 	return add_nondir(dentry, inode);
 }
 
Index: linux-2.6/fs/nfs/inode.c
===================================================================
--- linux-2.6.orig/fs/nfs/inode.c
+++ linux-2.6/fs/nfs/inode.c
@@ -365,7 +365,7 @@ nfs_fhget(struct super_block *sb, struct
 	dprintk("NFS: nfs_fhget(%s/%Ld ct=%d)\n",
 		inode->i_sb->s_id,
 		(long long)NFS_FILEID(inode),
-		atomic_read(&inode->i_count));
+		inode->i_count);
 
 out:
 	return inode;
@@ -1149,7 +1149,7 @@ static int nfs_update_inode(struct inode
 
 	dfprintk(VFS, "NFS: %s(%s/%ld ct=%d info=0x%x)\n",
 			__func__, inode->i_sb->s_id, inode->i_ino,
-			atomic_read(&inode->i_count), fattr->valid);
+			inode->i_count, fattr->valid);
 
 	if ((fattr->valid & NFS_ATTR_FATTR_FILEID) && nfsi->fileid != fattr->fileid)
 		goto out_fileid;
Index: linux-2.6/fs/nilfs2/mdt.c
===================================================================
--- linux-2.6.orig/fs/nilfs2/mdt.c
+++ linux-2.6/fs/nilfs2/mdt.c
@@ -466,7 +466,7 @@ nilfs_mdt_new_common(struct the_nilfs *n
 		inode->i_sb = sb; /* sb may be NULL for some meta data files */
 		inode->i_blkbits = nilfs->ns_blocksize_bits;
 		inode->i_flags = 0;
-		atomic_set(&inode->i_count, 1);
+		inode->i_count = 1;
 		inode->i_nlink = 1;
 		inode->i_ino = ino;
 		inode->i_mode = S_IFREG;
Index: linux-2.6/fs/nilfs2/namei.c
===================================================================
--- linux-2.6.orig/fs/nilfs2/namei.c
+++ linux-2.6/fs/nilfs2/namei.c
@@ -221,7 +221,9 @@ static int nilfs_link(struct dentry *old
 
 	inode->i_ctime = CURRENT_TIME;
 	inode_inc_link_count(inode);
-	atomic_inc(&inode->i_count);
+	spin_lock(&inode->i_lock);
+	inode->i_count++;
+	spin_unlock(&inode->i_lock);
 
 	err = nilfs_add_nondir(dentry, inode);
 	if (!err)
Index: linux-2.6/fs/ocfs2/namei.c
===================================================================
--- linux-2.6.orig/fs/ocfs2/namei.c
+++ linux-2.6/fs/ocfs2/namei.c
@@ -719,7 +719,9 @@ static int ocfs2_link(struct dentry *old
 		goto out_commit;
 	}
 
-	atomic_inc(&inode->i_count);
+	spin_lock(&inode->i_lock);
+	inode->i_count++;
+	spin_unlock(&inode->i_lock);
 	dentry->d_op = &ocfs2_dentry_ops;
 	d_instantiate(dentry, inode);
 
Index: linux-2.6/fs/reiserfs/file.c
===================================================================
--- linux-2.6.orig/fs/reiserfs/file.c
+++ linux-2.6/fs/reiserfs/file.c
@@ -39,7 +39,7 @@ static int reiserfs_file_release(struct
 	BUG_ON(!S_ISREG(inode->i_mode));
 
 	/* fast out for when nothing needs to be done */
-	if ((atomic_read(&inode->i_count) > 1 ||
+	if ((inode->i_count > 1 ||
 	     !(REISERFS_I(inode)->i_flags & i_pack_on_close_mask) ||
 	     !tail_has_to_be_packed(inode)) &&
 	    REISERFS_I(inode)->i_prealloc_count <= 0) {
@@ -94,7 +94,7 @@ static int reiserfs_file_release(struct
 	if (!err)
 		err = jbegin_failure;
 
-	if (!err && atomic_read(&inode->i_count) <= 1 &&
+	if (!err && inode->i_count <= 1 &&
 	    (REISERFS_I(inode)->i_flags & i_pack_on_close_mask) &&
 	    tail_has_to_be_packed(inode)) {
 		/* if regular file is released by last holder and it has been
Index: linux-2.6/fs/reiserfs/namei.c
===================================================================
--- linux-2.6.orig/fs/reiserfs/namei.c
+++ linux-2.6/fs/reiserfs/namei.c
@@ -1155,7 +1155,9 @@ static int reiserfs_link(struct dentry *
 	inode->i_ctime = CURRENT_TIME_SEC;
 	reiserfs_update_sd(&th, inode);
 
-	atomic_inc(&inode->i_count);
+	spin_lock(&inode->i_lock);
+	inode->i_count++;
+	spin_unlock(&inode->i_lock);
 	d_instantiate(dentry, inode);
 	retval = journal_end(&th, dir->i_sb, jbegin_count);
 	reiserfs_write_unlock(dir->i_sb);
Index: linux-2.6/fs/reiserfs/stree.c
===================================================================
--- linux-2.6.orig/fs/reiserfs/stree.c
+++ linux-2.6/fs/reiserfs/stree.c
@@ -1440,7 +1440,7 @@ static int maybe_indirect_to_direct(stru
 	 ** reading in the last block.  The user will hit problems trying to
 	 ** read the file, but for now we just skip the indirect2direct
 	 */
-	if (atomic_read(&inode->i_count) > 1 ||
+	if (inode->i_count > 1 ||
 	    !tail_has_to_be_packed(inode) ||
 	    !page || (REISERFS_I(inode)->i_flags & i_nopack_mask)) {
 		/* leave tail in an unformatted node */
Index: linux-2.6/fs/sysv/namei.c
===================================================================
--- linux-2.6.orig/fs/sysv/namei.c
+++ linux-2.6/fs/sysv/namei.c
@@ -126,7 +126,9 @@ static int sysv_link(struct dentry * old
 
 	inode->i_ctime = CURRENT_TIME_SEC;
 	inode_inc_link_count(inode);
-	atomic_inc(&inode->i_count);
+	spin_lock(&inode->i_lock);
+	inode->i_count++;
+	spin_unlock(&inode->i_lock);
 
 	return add_nondir(dentry, inode);
 }
Index: linux-2.6/fs/ubifs/dir.c
===================================================================
--- linux-2.6.orig/fs/ubifs/dir.c
+++ linux-2.6/fs/ubifs/dir.c
@@ -538,7 +538,9 @@ static int ubifs_link(struct dentry *old
 
 	lock_2_inodes(dir, inode);
 	inc_nlink(inode);
-	atomic_inc(&inode->i_count);
+	spin_lock(&inode->i_lock);
+	inode->i_count++;
+	spin_unlock(&inode->i_lock);
 	inode->i_ctime = ubifs_current_time(inode);
 	dir->i_size += sz_change;
 	dir_ui->ui_size = dir->i_size;
Index: linux-2.6/fs/ubifs/super.c
===================================================================
--- linux-2.6.orig/fs/ubifs/super.c
+++ linux-2.6/fs/ubifs/super.c
@@ -340,7 +340,7 @@ static void ubifs_delete_inode(struct in
 		goto out;
 
 	dbg_gen("inode %lu, mode %#x", inode->i_ino, (int)inode->i_mode);
-	ubifs_assert(!atomic_read(&inode->i_count));
+	ubifs_assert(!inode->i_count);
 	ubifs_assert(inode->i_nlink == 0);
 
 	truncate_inode_pages(&inode->i_data, 0);
Index: linux-2.6/fs/udf/namei.c
===================================================================
--- linux-2.6.orig/fs/udf/namei.c
+++ linux-2.6/fs/udf/namei.c
@@ -1091,7 +1091,9 @@ static int udf_link(struct dentry *old_d
 	inc_nlink(inode);
 	inode->i_ctime = current_fs_time(inode->i_sb);
 	mark_inode_dirty(inode);
-	atomic_inc(&inode->i_count);
+	spin_lock(&inode->i_lock);
+	inode->i_count++;
+	spin_unlock(&inode->i_lock);
 	d_instantiate(dentry, inode);
 	unlock_kernel();
 
Index: linux-2.6/fs/ufs/namei.c
===================================================================
--- linux-2.6.orig/fs/ufs/namei.c
+++ linux-2.6/fs/ufs/namei.c
@@ -178,7 +178,9 @@ static int ufs_link (struct dentry * old
 
 	inode->i_ctime = CURRENT_TIME_SEC;
 	inode_inc_link_count(inode);
-	atomic_inc(&inode->i_count);
+	spin_lock(&inode->i_lock);
+	inode->i_count++;
+	spin_unlock(&inode->i_lock);
 
 	error = ufs_add_nondir(dentry, inode);
 	unlock_kernel();