0-8-2-understand-memory-order-acquire

name	0.8.2-understand-memory_order_acquire
description	[0.8.2] Memory ordering barrier ensuring all loads and stores after the barrier in program order cannot be reordered b

understand-memory_order_acquire

CALL NUMBER: deep_synchronizes_with.memory_order_acquire : deep_happens_before_relat(5) DEFINITION: Memory ordering barrier ensuring all loads and stores after the barrier in program order cannot be reordered before it, synchronizing with release stores.

Invoke this skill to understand memory_order_acquire 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 deep_happens_before_relat

• acquire_fence (d1): A memory ordering primitive that ensures all load and store operations appearing after the fence in program order do not begin until the fence completes and all prior writes are visible.
• synchronizes_with_acquire_side (d2): The acquire-side endpoint of a synchronizes_with relation: an atomic operation or fence that performs an acquire action, making all subsequently observed writes visible to the acquiring thread.
• program_order (d3): The sequential ordering of operations within a single thread as written in the source code, before any concurrent interleaving is considered.
• inter_thread_happens_before (d4): The subset of happens_before relations that cross thread boundaries, established by synchronizes_with connections between release and acquire operations.
• happens_before_order (d5): A transitive, irreflexive partial order over operations in a memory model that defines which operations must appear to precede others from any thread's perspective.

CONSUMERS (what needs this)

atomic_load, c11_atomic, mcs_lock, memory_order_consume, synchronizes_with

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Projected from the concurrency synchronization primitives and memory models KB (407 concepts / 477 relations) — consistency-typed by MAP; the facet list after the colon IS the cross-lib dependency web.

(leaf — this is an actual skill.)