Re: [PATCH 1/3] nodemask: Introduce for_each_node_mask_wrap/for_each_node_state_wrap()

[Yury Norov <yury.norov@gmail.com>]

On Tue, Dec 03, 2024 at 04:36:10PM +0100, Andrea Righi wrote:
> Introduce NUMA node iterators to support circular iteration, starting
> from a specified node.
> 
> Signed-off-by: Andrea Righi <arighi@nvidia.com>

Acked-by: Yury Norov <yury.norov@gmail.com>

> ---
>  include/linux/nodemask.h | 14 ++++++++++++++
>  1 file changed, 14 insertions(+)
> 
> diff --git a/include/linux/nodemask.h b/include/linux/nodemask.h
> index b61438313a73..7ba35c65ab99 100644
> --- a/include/linux/nodemask.h
> +++ b/include/linux/nodemask.h
> @@ -392,6 +392,16 @@ static inline void __nodes_fold(nodemask_t *dstp, const nodemask_t *origp,
>  	for ((node) = 0; (node) < 1 && !nodes_empty(mask); (node)++)
>  #endif /* MAX_NUMNODES */
>  
> +#if MAX_NUMNODES > 1
> +#define for_each_node_mask_wrap(node, mask, start)			\
> +	for_each_set_bit_wrap((node), (mask).bits, MAX_NUMNODES, (start))
> +#else /* MAX_NUMNODES == 1 */
> +#define for_each_node_mask_wrap(node, mask, start)			\
> +	for ((node) = 0;						\
> +	     (node) < 1 && !nodes_empty(mask);				\
> +	     (node)++, (void)(start))
> +#endif /* MAX_NUMNODES */
> +
>  /*
>   * Bitmasks that are kept for all the nodes.
>   */
> @@ -441,6 +451,9 @@ static inline int num_node_state(enum node_states state)
>  #define for_each_node_state(__node, __state) \
>  	for_each_node_mask((__node), node_states[__state])
>  
> +#define for_each_node_state_wrap(__node, __state, __start) \
> +	for_each_node_mask_wrap((__node), node_states[__state], __start)
> +
>  #define first_online_node	first_node(node_states[N_ONLINE])
>  #define first_memory_node	first_node(node_states[N_MEMORY])
>  static inline unsigned int next_online_node(int nid)
> @@ -535,6 +548,7 @@ static inline int node_random(const nodemask_t *maskp)
>  
>  #define for_each_node(node)	   for_each_node_state(node, N_POSSIBLE)
>  #define for_each_online_node(node) for_each_node_state(node, N_ONLINE)
> +#define for_each_online_node_wrap(node, start) for_each_node_state(node, N_ONLINE, start)
>  
>  /*
>   * For nodemask scratch area.
> -- 
> 2.47.1