rht_for_each_from(9)

💅 rht_for_each_from(9) — the Kernel API Manual, bestie edition

okay so picture this: you're deep in the Linux kernel, you've got a hash chain, and you don't wanna start from the top like a rookie. You wanna start from a specific head. That's literally this macro. It's the rht_for_each_from girlies' moment and she ate. ✨

No cap, this is a loop macro — you give it a cursor, a starting point, a bucket table and a hash value, and it walks the chain for you. Group-chat energy: "we're iterating, we're iterating, we're done." 🦋

✨ SYNOPSIS ✨

rht_for_each_from (pos , head , tbl , hash );

🎀 ARGUMENTS 🎀

• pos — the struct rhash_head you're using as your loop cursor. She's the main character of the loop, the one that moves. 💅
• head — the struct rhash_head to start from. Like, you're not starting at the beginning bestie, you're starting here. 📍
• tbl — the struct bucket_table. The whole vibe container, iykyk. 🪣
• hash — the hash value / bucket index. That's your little map coordinate in the table. 🔥

🌈 SEE ALSO 🌈

okay this is the part where we tag everyone in the group chat, and there are so many of you, and I love that for us. Go read these when you're done here:

• the 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(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_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)

lowkey important: that SEE ALSO list is long for a reason — it's the whole rhashtable friend group. Don't skip them, they're iconic. 👑

💖 sign-off time: this absolute banger lives in ./include/linux, and it's dated October 2026. Manual page name is rht_for_each_from(9), part of the Kernel API Manual. slay, go iterate something. 😭🫶🌸