0-4-4-understand-mcs-lock-qnode

name	0.4.4-understand-mcs_lock_qnode
description	[0.4.4] Thread-local queue node containing locked flag and successor pointer; must be cache-aligned and allocated per-

understand-mcs_lock_qnode

CALL NUMBER: deep_spinlock.mcs_lock_qnode DEFINITION: Thread-local queue node containing locked flag and successor pointer; must be cache-aligned and allocated per-thread to enable local spinning without shared contention.

Invoke this skill to understand mcs_lock_qnode down to its primitives. The RELATIVE ROOT below is the least-fixed-point closure of everything it bundles from — the full import cone, grouped by the lib each prim comes from. Projected from a prover-typed KB (MAP/SWI-Prolog consistency gate): every reference below resolves.

THE RELATIVE ROOT (the import cone, by lib)

from ?

• cache_alignment (d1): Placement of data structures on memory boundaries matching cache line size, typically 64 bytes, preventing false sharing between adjacent data.

CONSUMERS (what needs this)

mcs_lock_acquire, mcs_lock_local_spinning

---

Projected from the concurrency synchronization primitives and memory models KB (155 concepts / 137 relations) — consistency-typed by MAP; the facet list after the colon IS the cross-lib dependency web.

(leaf — this is an actual skill.)