radix_tree_deref_slot(9)

okay so bestie, welcome to radix_tree_deref_slot(9) from the Kernel API Manual 💖 this is the little “dereference a slot” moment, and it is giving “I know my tree locks” energy. Periodt.

✨ NAME ✨

radix_tree_deref_slot — dereference a slot. That’s the whole name, and she ate. 🎀

🫶 SYNOPSIS 🫶

void * radix_tree_deref_slot (void __rcu **slot );

🌸 ARGUMENTS 🌸

• slot — the slot pointer, returned by radix_tree_lookup_slot. That’s your lil handle, bestie; don’t invent your own. 💅

🎀 DESCRIPTION 🎀

Okay so here’s the vibe check: this function is for use with radix_tree_lookup_slot — they’re a matching set, iykyk. 🦋

The caller must hold the tree at least read locked across slot lookup and dereference. Like, across both steps, no gaps, no “oops I forgot the lock” main character moments. 😭

That’s not required if the write lock is held (ie. items cannot be concurrently inserted). So if you already have the write lock, you’re chilling. 🫶

If only the read lock is held, radix_tree_deref_retry must be used to confirm validity of the pointer. Do not skip this, bestie — it’s literally the validity check. 💀

💖 RETURN 💖

The return is the entry stored in that slot. That’s what you get, and it’s iconic. 👑

🦋 SEE ALSO 🦋

Go touch grass in these related pages and files, fr fr:

• Kernel file: ./include/linux/radix-tree.h
• struct radix_tree_iter(9)
• Radix-tree synchronization(9)
• radix_tree_deref_slot_protected(9)
• radix_tree_deref_retry(9)
• radix_tree_exception(9)
• radix_tree_iter_init(9)
• radix_tree_next_chunk(9)
• radix_tree_iter_lookup(9)
• radix_tree_iter_retry(9)
• radix_tree_iter_resume(9)
• radix_tree_chunk_size(9)
• radix_tree_next_slot(9)
• radix_tree_for_each_slot(9)
• radix_tree_for_each_tagged(9)

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mwah 💋 — this page’s source/version is ./include/linux, and it’s dated October 2026; it’s a Kernel API Manual situation, and that’s the cute lil sign-off. 🎀✨