rht_for_each_rcu(9)

🎀 NAME 🎀

okay so bestie, you're on the rht_for_each_rcu(9) page in the Kernel API Manual, and the whole point is literally: iterate over rcu hash chain. no cap. 💅

✨ SYNOPSIS ✨

rht_for_each_rcu (pos , tbl , hash );

🦋 ARGUMENTS 🦋

• pos — the struct rhash_head to use as a loop cursor. that's your main character pointer fr fr.
• tbl — the struct bucket_table. the table you're cruising through, lowkey.
• hash — the hash value / bucket index. the lil address vibe that tells you which chain to hit.

🔥 DESCRIPTION 🔥

This hash chain list-traversal primitive may safely run concurrently with the _rcu mutation primitives such as rhashtable_insert as long as the traversal is guarded by rcu_read_lock.

bestie, read that again: concurrent-safe is conditional. the rcu_read_lock guard is not optional, periodt. 💀

🌈 SEE ALSO 🌈

The kernel file ./include/linux/rhashtable.h is in the group chat, along with:

• 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_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_lookup_get_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 page's source/version footer says ./include/linux, dated October 2026, and it's still the rht_for_each_rcu(9) page. 🫶