futex_top_waiter(9)

✨ futex_top_waiter(9) ✨

bestie, welcome to the Kernel API Manual page for futex_top_waiter(9) — yes, the Kernel API Manual, we're doing kernel-core realness today 🫶

💅 NAME 💅

futex_top_waiter — Return the highest priority waiter on a futex 👑

🌸 SYNOPSIS 🌸

struct futex_q * futex_top_waiter (struct futex_hash_bucket *hb , union
futex_key *key );

🎀 ARGUMENTS 🎀

• hb — the hash bucket the futex_q's reside in.
• key — the futex key (to distinguish it from other futex futex_q's).

🦋 DESCRIPTION 🦋

okay so the one big rule, and I mean it, no cap: this must be called with the hb lock held. Not optional, not "maybe later", not "I'll hold it in spirit" — hold the lock, bestie. Periodt 🔒✨

🌈 SEE ALSO 🌈

• Kernel file ./kernel/futex/core.c
• __futex_hash(9)
• futex_setup_timer(9)
• get_futex_key(9)
• fault_in_user_writeable(9)
• wait_for_owner_exiting(9)
• __futex_unqueue(9)
• futex_unqueue(9)
• futex_exit_recursive(9)

okay that's the whole page, mwah 💖 — source/version is ./kernel/futex, stamped October 2026, and it's giving kernel manual realness 🎀🦋