Re: [RFC v2 04/10] vfs: add init and exit support

[Dave Chinner <david@fromorbit.com>]

On Sun, Sep 23, 2012 at 08:56:29PM +0800, zwu.kernel@gmail.com wrote:
> From: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>
> 
>   Add initialization function to create some
> key data structures when hot tracking is enabled;
> Clean up them when hot tracking is disabled
> 
> Signed-off-by: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>
> ---
>  fs/hot_tracking.c |   60 +++++++++++++++++++++++++++++++++++++++++++++++++++++
>  fs/hot_tracking.h |    2 +
>  fs/namespace.c    |    4 +++
>  fs/super.c        |    6 +++++
>  4 files changed, 72 insertions(+), 0 deletions(-)
> 
> diff --git a/fs/hot_tracking.c b/fs/hot_tracking.c
> index f97e8a6..fa89f70 100644
> --- a/fs/hot_tracking.c
> +++ b/fs/hot_tracking.c
> @@ -135,6 +135,51 @@ static void hot_rb_free_hot_range_item(struct hot_range_item *hr)
>  	}
>  }
>  
> +static int hot_rb_remove_hot_inode_item(struct hot_inode_tree *tree,
> +                                struct hot_inode_item *he)

hot_inode_item_remove()

> +{
> +        int ret = 0;
> +        rb_erase(&he->rb_node, &tree->map);
> +        he->in_tree = 0;
> +        return ret;
> +}
> +
> +static int hot_rb_remove_hot_range_item(struct hot_range_tree *tree,
> +                                struct hot_range_item *hr)

hot_range_item_remove()

(repeat for other function names ;)

> +{
> +        int ret = 0;
> +        rb_erase(&hr->rb_node, &tree->map);
> +        hr->in_tree = 0;
> +        return ret;
> +}

these can probably be void functions are they don't use the return
value at all.

> +
> +/* Frees the entire hot_inode_tree. */
> +static void hot_rb_inode_tree_free(struct hot_info *root)
> +{
> +	struct rb_node *node, *node2;
> +	struct hot_inode_item *he;
> +	struct hot_range_item *hr;
> +
> +	/* Free hot inode and range trees on fs root */
> +	node = rb_first(&root->hot_inode_tree.map);
> +
> +	while (node) {

	while ((node = rb_first(&root->hot_inode_tree.map))) {

> +		he = rb_entry(node, struct hot_inode_item, rb_node);
> +
> +		node2 = rb_first(&he->hot_range_tree.map);
> +		while (node2) {

		while ((node2 = rb_first(&he->hot_range_tree.map))) {

.....
>  
> +	if (sb->s_hotinfo.mount_opt & HOT_MOUNT_HOT_TRACK)
> +		hot_track_exit(sb);
> +

Let the filesystems call in .put_super()

>  	down_write(&namespace_sem);
>  	br_write_lock(&vfsmount_lock);
>  	event++;
> diff --git a/fs/super.c b/fs/super.c
> index 7eb3b0c..0999d5c 100644
> --- a/fs/super.c
> +++ b/fs/super.c
> @@ -1153,6 +1153,9 @@ mount_fs(struct file_system_type *type, int flags, const char *name, void *data)
>  	WARN_ON(sb->s_bdi == &default_backing_dev_info);
>  	sb->s_flags |= MS_BORN;
>  
> +	if (hottrack)
> +		hot_track_init(sb, name);

And call this in .fill_super() after parsing the hottrack argument.

Cheers,

Dave.
-- 
Dave Chinner
david@fromorbit.com