Re: [PATCH v2 01/29] radix-tree: Introduce radix_tree_empty

Jan Kara
2016-05-03T14:25:01Z

On Thu 14-04-16 10:16:22, Matthew Wilcox wrote:
> The irqdomain code was checking for 0 or 1 entries, not 0 entries like
> the comment said they were. Introduce a new helper that will actually
> check for an empty tree.
>
> Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
> Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>

The patch looks good. You can add:

Reviewed-by: Jan Kara <jack@suse.cz>

Honza

> ---
> include/linux/radix-tree.h | 5 +++++
> kernel/irq/irqdomain.c | 7 +------
> 2 files changed, 6 insertions(+), 6 deletions(-)
>
> diff --git a/include/linux/radix-tree.h b/include/linux/radix-tree.h
> index 51a97ac..83f708e 100644
> --- a/include/linux/radix-tree.h
> +++ b/include/linux/radix-tree.h
> @@ -136,6 +136,11 @@ do { \
> (root)->rnode = NULL; \
> } while (0)
>
> +static inline bool radix_tree_empty(struct radix_tree_root *root)
> +{
> + return root->rnode == NULL;
> +}
> +
> /**
> * Radix-tree synchronization
> *
> diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
> index 3a519a0..ba3f60d 100644
> --- a/kernel/irq/irqdomain.c
> +++ b/kernel/irq/irqdomain.c
> @@ -139,12 +139,7 @@ void irq_domain_remove(struct irq_domain *domain)
> {
> mutex_lock(&irq_domain_mutex);
>
> - /*
> - * radix_tree_delete() takes care of destroying the root
> - * node when all entries are removed. Shout if there are
> - * any mappings left.
> - */
> - WARN_ON(domain->revmap_tree.height);
> + WARN_ON(!radix_tree_empty(&domain->revmap_tree));
>
> list_del(&domain->link);
>
> --
> 2.8.0.rc3
>
>
--
Jan Kara <jack@suse.com>
SUSE Labs, CR