[PATCH dpdk 2/2] rib: add mode to include top-level route in traversal

[Medvedkin, Vladimir]

Hi Robin,

I'd suggest to reflect changes in release notes. Please find other 
comments inline.

On 5/18/2026 10:59 AM, Robin Jarry wrote:
> rte_rib_get_nxt() and rte_rib6_get_nxt() skip the exact match
> top-level route when iterating subroutes. This is the expected behavior
> in most cases but some users need the full subtree including the root.
>
> Add a RTE_RIB_GET_NXT_ALL_TOP (and RTE_RIB6_GET_NXT_ALL_TOP) mode
> that uses >= instead of > when comparing depths so that the top-level
> route is returned as well.
>
> Signed-off-by: Robin Jarry <rjarry at redhat.com>
> ---
>   app/test/test_rib.c  | 16 ++++++++++++++++
>   app/test/test_rib6.c | 16 ++++++++++++++++
>   lib/rib/rte_rib.c    | 12 ++++++++++--
>   lib/rib/rte_rib.h    |  4 ++++
>   lib/rib/rte_rib6.c   | 12 ++++++++++--
>   lib/rib/rte_rib6.h   |  4 ++++
>   6 files changed, 60 insertions(+), 4 deletions(-)
>
> diff --git a/app/test/test_rib.c b/app/test/test_rib.c
> index a4a683140df3..f56490e67ec0 100644
> --- a/app/test/test_rib.c
> +++ b/app/test/test_rib.c
> @@ -300,6 +300,7 @@ test_tree_traversal(void)
>   	uint32_t ip1 = RTE_IPV4(10, 10, 10, 0);
>   	uint32_t ip2 = RTE_IPV4(10, 10, 130, 80);
>   	uint8_t depth = 30;
> +	unsigned int num;
>   
>   	config.max_nodes = MAX_RULES;
>   	config.ext_sz = 0;
> @@ -313,11 +314,26 @@ test_tree_traversal(void)
>   	node = rte_rib_insert(rib, ip2, depth);
>   	RTE_TEST_ASSERT(node != NULL, "Failed to insert rule\n");
>   
> +	node = rte_rib_insert(rib, 0, 0);
> +	RTE_TEST_ASSERT(node != NULL, "Failed to insert default rule\n");
> +
>   	node = NULL;
>   	node = rte_rib_get_nxt(rib, RTE_IPV4(10, 10, 130, 0), 24, node,
>   			RTE_RIB_GET_NXT_ALL);
>   	RTE_TEST_ASSERT(node != NULL, "Failed to get rib_node\n");
>   
> +	num = 0;
> +	node = NULL;
> +	while ((node = rte_rib_get_nxt(rib, 0, 0, node, RTE_RIB_GET_NXT_ALL)) != NULL)
> +		num++;
> +	RTE_TEST_ASSERT(num == 2, "Invalid number of routes\n");
> +
> +	num = 0;
> +	node = NULL;
> +	while ((node = rte_rib_get_nxt(rib, 0, 0, node, RTE_RIB_GET_NXT_ALL_TOP)) != NULL)
> +		num++;
> +	RTE_TEST_ASSERT(num == 3, "Default route not returned by rte_rib_get_nxt\n");
> +
>   	rte_rib_free(rib);
>   
>   	return TEST_SUCCESS;
> diff --git a/app/test/test_rib6.c b/app/test/test_rib6.c
> index 0295a9640cfa..542c955eee8c 100644
> --- a/app/test/test_rib6.c
> +++ b/app/test/test_rib6.c
> @@ -300,7 +300,9 @@ test_tree_traversal(void)
>   	struct rte_ipv6_addr ip = RTE_IPV6(0x0a00, 0x0282, 0, 0, 0, 0, 0, 0);
>   	struct rte_ipv6_addr ip1 = RTE_IPV6(0x0a00, 0x0200, 0, 0, 0, 0, 0, 0);
>   	struct rte_ipv6_addr ip2 = RTE_IPV6(0x0a00, 0x0282, 0, 0, 0, 0, 0, 0x0050);
> +	struct rte_ipv6_addr unspec = RTE_IPV6(0, 0, 0, 0, 0, 0, 0, 0);
>   	uint8_t depth = 126;
> +	unsigned int num;
>   
>   	config.max_nodes = MAX_RULES;
>   	config.ext_sz = 0;
> @@ -312,11 +314,25 @@ test_tree_traversal(void)
>   	RTE_TEST_ASSERT(node != NULL, "Failed to insert rule\n");
>   	node = rte_rib6_insert(rib, &ip2, depth);
>   	RTE_TEST_ASSERT(node != NULL, "Failed to insert rule\n");
> +	node = rte_rib6_insert(rib, &unspec, 0);
> +	RTE_TEST_ASSERT(node != NULL, "Failed to insert default route\n");
>   
>   	node = NULL;
>   	node = rte_rib6_get_nxt(rib, &ip, 32, node, RTE_RIB6_GET_NXT_ALL);
>   	RTE_TEST_ASSERT(node != NULL, "Failed to get rib_node\n");
>   
> +	num = 0;
> +	node = NULL;
> +	while ((node = rte_rib6_get_nxt(rib, 0, 0, node, RTE_RIB6_GET_NXT_ALL)) != NULL)
second arg should be &unspec
> +		num++;
> +	RTE_TEST_ASSERT(num == 2, "Invalid number of routes\n");
> +
> +	num = 0;
> +	node = NULL;
> +	while ((node = rte_rib6_get_nxt(rib, 0, 0, node, RTE_RIB6_GET_NXT_ALL_TOP)) != NULL)
same here
> +		num++;
> +	RTE_TEST_ASSERT(num == 3, "Default route not returned by rte_rib6_get_nxt\n");
> +
>   	rte_rib6_free(rib);
>   
>   	return TEST_SUCCESS;
> diff --git a/lib/rib/rte_rib.c b/lib/rib/rte_rib.c
> index 89061829a23c..a3c287e215ec 100644
> --- a/lib/rib/rte_rib.c
> +++ b/lib/rib/rte_rib.c
> @@ -167,6 +167,14 @@ rte_rib_lookup_exact(struct rte_rib *rib, uint32_t ip, uint8_t depth)
>   	return __rib_lookup_exact(rib, ip, depth);
>   }
>   
> +static bool
> +depth_match(struct rte_rib_node *node, uint8_t depth, int flag)

3d arg enum rte_rib_nxt_mode mode?

> +{
> +	if (flag == RTE_RIB_GET_NXT_ALL_TOP)
> +		return node->depth >= depth;
> +	return node->depth > depth;
> +}
> +
>   /*
>    *  Traverses on subtree and retrieves more specific routes
>    *  for a given in args ip/depth prefix
> @@ -195,7 +203,7 @@ rte_rib_get_nxt(struct rte_rib *rib, uint32_t ip,
>   			tmp = tmp->parent;
>   			if (is_valid_node(tmp) &&
>   					(is_covered(tmp->ip, ip, depth) &&
> -					(tmp->depth > depth)))
> +					(depth_match(tmp, depth, mode))))
extra parenthesis, same for v6
>   				return tmp;
>   		}
>   		tmp = (tmp->parent) ? tmp->parent->right : NULL;
> @@ -203,7 +211,7 @@ rte_rib_get_nxt(struct rte_rib *rib, uint32_t ip,
>   	while (tmp) {
>   		if (is_valid_node(tmp) &&
>   				(is_covered(tmp->ip, ip, depth) &&
> -				(tmp->depth > depth))) {
> +				(depth_match(tmp, depth, mode)))) {
>   			prev = tmp;
>   			if (mode == RTE_RIB_GET_NXT_COVER)
>   				return prev;
> diff --git a/lib/rib/rte_rib.h b/lib/rib/rte_rib.h
> index 0fabfb2a41a6..5e72fa9273e2 100644
> --- a/lib/rib/rte_rib.h
> +++ b/lib/rib/rte_rib.h
> @@ -31,6 +31,8 @@ enum rte_rib_nxt_mode {
>   	RTE_RIB_GET_NXT_ALL,
>   	/** get first matched subroutes in a RIB tree, excluding any exact match top-level route */
>   	RTE_RIB_GET_NXT_COVER,
> +	/** get all subroutes in a RIB tree, including the exact match top-level route, if any */
> +	RTE_RIB_GET_NXT_ALL_TOP,
>   };
>   
>   struct rte_rib;
> @@ -125,6 +127,8 @@ rte_rib_lookup_exact(struct rte_rib *rib, uint32_t ip, uint8_t depth);
>    *   get all prefixes from subtrie
>    *  -RTE_RIB_GET_NXT_COVER
>    *   get only first more specific prefix even if it have more specifics
> + *  -RTE_RIB_GET_NXT_ALL_TOP
> + *   get the top-level exact matching prefix, if any

RTE_RIB_GET_NXT_ALL_TOP is effectively RTE_RIB_GET_NXT_ALL + exact 
match. Better definition would be something like:

get all prefixes from the subtrie, including the ip/depth prefix itself 
if present. Top prefix is returned last.

>    * @return
>    *  pointer to the next more specific prefix
>    *  NULL if there is no prefixes left
> diff --git a/lib/rib/rte_rib6.c b/lib/rib/rte_rib6.c
> index c23881f6247e..5114fb522e3e 100644
> --- a/lib/rib/rte_rib6.c
> +++ b/lib/rib/rte_rib6.c
> @@ -186,6 +186,14 @@ rte_rib6_lookup_exact(struct rte_rib6 *rib,
>   	return NULL;
>   }
>   
> +static bool
> +depth_match(struct rte_rib6_node *node, uint8_t depth, enum rte_rib6_nxt_mode mode)
> +{
> +	if (mode == RTE_RIB6_GET_NXT_ALL_TOP)
> +		return node->depth >= depth;
> +	return node->depth > depth;
> +}
> +
>   /*
>    *  Traverses on subtree and retrieves more specific routes
>    *  for a given in args ip/depth prefix
> @@ -219,7 +227,7 @@ rte_rib6_get_nxt(struct rte_rib6 *rib,
>   			tmp = tmp->parent;
>   			if (is_valid_node(tmp) &&
>   					(rte_ipv6_addr_eq_prefix(&tmp->ip, &tmp_ip, depth) &&
> -					(tmp->depth > depth)))
> +					(depth_match(tmp, depth, mode))))
>   				return tmp;
>   		}
>   		tmp = (tmp->parent != NULL) ? tmp->parent->right : NULL;
> @@ -227,7 +235,7 @@ rte_rib6_get_nxt(struct rte_rib6 *rib,
>   	while (tmp) {
>   		if (is_valid_node(tmp) &&
>   				(rte_ipv6_addr_eq_prefix(&tmp->ip, &tmp_ip, depth) &&
> -				(tmp->depth > depth))) {
> +				(depth_match(tmp, depth, mode)))) {
>   			prev = tmp;
>   			if (mode == RTE_RIB6_GET_NXT_COVER)
>   				return prev;
> diff --git a/lib/rib/rte_rib6.h b/lib/rib/rte_rib6.h
> index ed2761492bc8..1d8b56b89b13 100644
> --- a/lib/rib/rte_rib6.h
> +++ b/lib/rib/rte_rib6.h
> @@ -32,6 +32,8 @@ enum rte_rib6_nxt_mode {
>   	RTE_RIB6_GET_NXT_ALL,
>   	/** get first matched subroutes in a RIB tree, excluding any exact match top-level route */
>   	RTE_RIB6_GET_NXT_COVER,
> +	/** get all subroutes in a RIB tree, including the exact match top-level route, if any */
> +	RTE_RIB6_GET_NXT_ALL_TOP,
>   };
>   
>   struct rte_rib6;
> @@ -184,6 +186,8 @@ rte_rib6_lookup_exact(struct rte_rib6 *rib,
>    *   get all prefixes from subtrie
>    *  -RTE_RIB6_GET_NXT_COVER
>    *   get only first more specific prefix even if it have more specifics
> + *  -RTE_RIB6_GET_NXT_ALL_TOP
> + *   get the top-level exact matching prefix, if any
>    * @return
>    *  pointer to the next more specific prefix
>    *  NULL if there is no prefixes left

-- 
Regards,
Vladimir