Add info_count to route_table for accurate RIB entry reporting #20206
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Let's get the frrbot problems cleaned up. This seems reasonable. |
mjstapp
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Dec 8, 2025
| * Helper to update a node's ->info pointer while keeping the table's | ||
| * info_count in sync. | ||
| */ | ||
| static inline void route_node_set_info(struct route_node *node, void *info) |
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so ... the problem with introducing this api in this way is that it will only work if used consistently, everywhere. and ... there are lots of places in the code that touch route_node->info. what do you expect to have happen there? doing something in the library seems like something that should work everywhere. doing something just for bgp should maybe just be done in bgp code?
BGP stores prefix destinations using the Patricia trie in lib/table.[ch]. This data structure creates auxiliary (glue) nodes to preserve tree structure invariants. These glue nodes have info == NULL and don't represent actual routes. Previously, `show ip bgp summary` reported "RIB entries" using the total node count, which incorrectly included glue nodes. For example, 4 actual prefixes might show as "RIB entries 7" due to 3 glue nodes. - Add `info_count` field to `struct route_table` that tracks only nodes with info != NULL. - Add route_node_set_info() helper to automatically maintain this counter when setting/clearing a node's info pointer. - Update BGP to use the new counter for accurate RIB entry reporting. Signed-off-by: Mike Dubrovsky <[email protected]>
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Description
This PR adds a new info_count field to struct route_table that tracks only nodes with actual data (info != NULL), excluding auxiliary/glue nodes that exist solely for the Patricia trie structure.
Problem
BGP stores prefix destinations using the Patricia trie in lib/table.[ch].
This data structure requires auxiliary glue nodes to preserve tree structure invariants.
The show ip bgp summary command displays "RIB entries" using route_table_count(),
which counts all nodes in the Patricia trie, including internal glue nodes.
This is misleading because glue nodes don't represent actual routes.
Example - Before (incorrect):
In this example, there are only 4 actual prefixes (PfxSnt 4), but "RIB entries" shows 7 because it includes 3 auxiliary glue nodes created by the Patricia trie structure.
Example - After (correct):
Solution
Add info_count field to struct route_table to track nodes with info != NULL
Add route_node_set_info() helper function that automatically maintains info_count when setting/clearing a node's info pointer
Update BGP to use route_node_set_info()