rhashtable_l...t_insert_key(9)

💖 NAME 💖

okay so bestie, this is the manual page for rhashtable_l...t_insert_key(9) from the Kernel API Manual ✨ — yes, the header is a little truncated, but the actual function is rhashtable_lookup_get_insert_key, and its whole job is lookup and insert object into hash table. No cap: it’s the “find it, or put it there” bestie of hash-table land 💅.

✨ SYNOPSIS ✨

Here’s the signature, verbatim because we do not mess with code 👑:

void * rhashtable_lookup_get_insert_key (struct rhashtable *ht , const
void *key , struct rhash_head *obj , const struct rhashtable_params
params );

🎀 ARGUMENTS 🎀

• ht — hash table. main character table energy 👑
• key — key. literally the key 🔑
• obj — pointer to hash head inside object. it’s giving object’s hash-head hookup 🪝
• params — hash table parameters. the table’s settings/vibes ✨

🦋 DESCRIPTION 🦋

so this function is just like rhashtable_lookup_insert_key, but the return value has different lore 😭:

• the object exists → it returns the object. hi bestie, you’re already here 💖
• it does not exist and the insertion was successful → it returns NULL. okay slay, fresh insert 🌱
• otherwise → it returns an ERR_PTR. not iconic, something went sideways 💀

🌈 SEE ALSO 🌈

bestie, go peek at the whole extended universe if you want the full lore 🫶:

• Kernel file ./include/linux/rhashtable.h
• struct bucket_table(9)
• rht_grow_above_75(9)
• rht_shrink_below_30(9)
• rht_grow_above_100(9)
• rht_grow_above_max(9)
• rht_for_each_from(9)
• rht_for_each(9)
• rht_for_each_entry_from(9)
• rht_for_each_entry(9)
• rht_for_each_entry_safe(9)
• rht_for_each_rcu_from(9)
• rht_for_each_rcu(9)
• rht_for_each_entry_rcu_from(9)
• rht_for_each_entry_rcu(9)
• rhl_for_each_rcu(9)
• rhl_for_each_entry_rcu(9)
• rhashtable_lookup(9)
• rhashtable_lookup_fast(9)
• rhltable_lookup(9)
• rhashtable_insert_fast(9)
• rhltable_insert_key(9)
• rhltable_insert(9)
• rhashtable_lookup_insert_fast(9)
• rhashtable_lookup_get_insert_fast(9)
• rhashtable_lookup_insert_key(9)
• rhashtable_remove_fast(9)
• rhltable_remove(9)
• rhashtable_replace_fast(9)
• rhltable_walk_enter(9)
• rhltable_free_and_destroy(9)

mwah 💋 this cute lil page came from ./include/linux and is dated October 2026 — periodt. 🎀