Re: [PATCH iproute2-next v4] rdma: display resource limits in curr/max format

[Leon Romanovsky <leonro@nvidia.com>]

On Wed, Jul 08, 2026 at 09:40:03PM +0800, Tao Cui wrote:
> From: Tao Cui <cuitao@kylinos.cn>
> 
> Parse the new RDMA_NLDEV_ATTR_RES_SUMMARY_ENTRY_MAX netlink attribute
> to show resource limits alongside current counts in curr/max format:
> 
>   Before: 0: mlx5_0: qp 123  cq 45  mr 200  pd 10
>   After:  0: mlx5_0: qp 123/131072  cq 45/65536  mr 200/1000000  pd 10/32768
> 
> JSON output provides both current and max fields per resource type
> (e.g. "qp": 123, "qp-max": 131072). Backward compatible: no output
> change when kernel lacks the new attribute.
> 
> Signed-off-by: Tao Cui <cuitao@kylinos.cn>
> Link: https://lore.kernel.org/all/20260615003646.168704-1-cui.tao@linux.dev/
> ---
> Changes in v4:
> - Add Link to the kernel patch that introduces the new uapi attribute.
> ---
>  rdma/include/uapi/rdma/rdma_netlink.h |  5 +++++

Please move changes to rdma_netlink.h into a separate commit using
the following format:
https://git.kernel.org/pub/scm/network/iproute2/iproute2-next.git/commit/rdma/include/uapi/rdma?id=85860c7dce2ce742ef0c6879b5c5bcbcecaaf717

Thanks

>  rdma/res.c                            | 21 ++++++++++++++++++++-
>  rdma/utils.c                          |  1 +
>  3 files changed, 26 insertions(+), 1 deletion(-)
> 
> diff --git a/rdma/include/uapi/rdma/rdma_netlink.h b/rdma/include/uapi/rdma/rdma_netlink.h
> index 4356ec4a..e5b8b065 100644
> --- a/rdma/include/uapi/rdma/rdma_netlink.h
> +++ b/rdma/include/uapi/rdma/rdma_netlink.h
> @@ -604,6 +604,11 @@ enum rdma_nldev_attr {
>  	RDMA_NLDEV_ATTR_FRMR_POOL_PINNED_HANDLES,	/* u32 */
>  	RDMA_NLDEV_ATTR_FRMR_POOL_KEY_KERNEL_VENDOR_KEY,	/* u64 */
>  
> +	/*
> +	 * Resource summary entry maximum value.
> +	 */
> +	RDMA_NLDEV_ATTR_RES_SUMMARY_ENTRY_MAX,		/* u64 */
> +
>  	/*
>  	 * Always the end
>  	 */
> diff --git a/rdma/res.c b/rdma/res.c
> index 062f0007..046935e2 100644
> --- a/rdma/res.c
> +++ b/rdma/res.c
> @@ -55,7 +55,26 @@ static int res_print_summary(struct nlattr **tb)
>  
>  		name = mnl_attr_get_str(nla_line[RDMA_NLDEV_ATTR_RES_SUMMARY_ENTRY_NAME]);
>  		curr = mnl_attr_get_u64(nla_line[RDMA_NLDEV_ATTR_RES_SUMMARY_ENTRY_CURR]);
> -		res_print_u64(name, curr, nla_line[RDMA_NLDEV_ATTR_RES_SUMMARY_ENTRY_CURR]);
> +		if (nla_line[RDMA_NLDEV_ATTR_RES_SUMMARY_ENTRY_MAX]) {
> +			uint64_t max;
> +			char max_name[64];
> +
> +			max = mnl_attr_get_u64(
> +				nla_line[RDMA_NLDEV_ATTR_RES_SUMMARY_ENTRY_MAX]);
> +			snprintf(max_name, sizeof(max_name), "%s-max", name);
> +			print_u64(PRINT_JSON, name, NULL, curr);
> +			print_u64(PRINT_JSON, max_name, NULL, max);
> +			if (!is_json_context()) {
> +				char buf[64];
> +
> +				snprintf(buf, sizeof(buf), "%s %" PRIu64 "/%" PRIu64 " ",
> +					 name, curr, max);
> +				pr_out("%s", buf);
> +			}
> +		} else {
> +			res_print_u64(name, curr,
> +				      nla_line[RDMA_NLDEV_ATTR_RES_SUMMARY_ENTRY_CURR]);
> +		}
>  	}
>  	return 0;
>  }
> diff --git a/rdma/utils.c b/rdma/utils.c
> index 87003b2c..90ea1c55 100644
> --- a/rdma/utils.c
> +++ b/rdma/utils.c
> @@ -480,6 +480,7 @@ static const enum mnl_attr_data_type nldev_policy[RDMA_NLDEV_ATTR_MAX] = {
>  	[RDMA_NLDEV_ATTR_EVENT_TYPE] = MNL_TYPE_U8,
>  	[RDMA_NLDEV_SYS_ATTR_MONITOR_MODE] = MNL_TYPE_U8,
>  	[RDMA_NLDEV_ATTR_STAT_OPCOUNTER_ENABLED] = MNL_TYPE_U8,
> +	[RDMA_NLDEV_ATTR_RES_SUMMARY_ENTRY_MAX] = MNL_TYPE_U64,
>  };
>  
>  static int rd_attr_check(const struct nlattr *attr, int *typep)
> -- 
> 2.43.0
> 
>