Reentrant mutex

A mutual-exclusion lock that its owning thread may acquire repeatedly, tracking recursion depth and releasing ownership only after a matching number of unlocks.

Version

v1 · 2026-09-08 · History

Domain-specific #

6442

Origin domain

concurrent computing

Subdomain

synchronization primitives

Core Idea

A reentrant mutex permits recursive acquisition by the current owner while excluding all other threads. The first acquisition records the owner and sets a count; owner reacquisition increments the count, each unlock decrements it and only zero releases the mutex to another thread. The abstraction is therefore identified by a declared carrier, a transformation or constraint over that carrier, and an invariant that tells an analyst whether the named structure is genuinely present.

The load-bearing residual is not the broad topic of concurrent computing. It is owner-counted mutual exclusion preventing self-deadlock in recursive call paths. That residual remains recognizable when examples, notation, scale, or implementation change, but it disappears if the carrier is mistyped, the condition that only the owner can use recursive acquisition and ownership is relinquished exactly when matched release count reaches zero fails, a neighboring object is substituted, or notation and topical resemblance replace the constitutive test.

Scope of Application

Reentrant mutex belongs to concurrent computing and is useful where the analyst can specify threads, mutex state, owner thread identity, acquisition count, lock and unlock operations, blocking queue, critical sections and error or fairness semantics, then evaluate only the owner can use recursive acquisition and ownership is relinquished exactly when matched release count reaches zero. The scope is broad within that domain but bounded by the need for only the owner can use recursive acquisition and ownership is relinquished exactly when matched release count reaches zero. The entry records a descriptive analytical identity; practical use requires the governing domain's evidence, standards, and safety obligations.

Clarity

The abstraction clarifies a crowded vocabulary by making only the owner can use recursive acquisition and ownership is relinquished exactly when matched release count reaches zero the center of the account. A claim should name the carrier, the governing operation or relation, the applicable assumptions, and the recognition test. A bare label is insufficient because the name Reentrant mutex can be used for a formal identity, an implementation, or a neighboring result unless carrier and convention are stated.

Manages Complexity

Without the abstraction, an analyst must reason directly over many local details: the carrier roles, admissibility assumptions, competing conventions, derived invariants, boundary cases, and proof or validation obligations specific to Reentrant mutex. Reentrant mutex compresses them into the roles in the structural signature. That compression permits comparison across instances without erasing the variables that determine validity. It also exposes which details may be varied safely and which are constitutive.

Abstract Reasoning

1. Identify the carrier. State what the elements, states, objects, or observations are: threads, mutex state, owner thread identity, acquisition count, lock and unlock operations, blocking queue, critical sections and error or fairness semantics. Reject examples whose alleged carrier belongs to a different problem. 2. Lock the constitutive rule. Express only the owner can use recursive acquisition and ownership is relinquished exactly when matched release count reaches zero independently of one notation or implementation.

Knowledge Transfer

Knowledge transfers strongly among subfields of concurrent computing because they reuse threads, mutex state, owner thread identity, acquisition count, lock and unlock operations, blocking queue, critical sections and error or fairness semantics, The first acquisition records the owner and sets a count; owner reacquisition increments the count, each unlock decrements it and only zero releases the mutex to another thread., and type the carrier, state every parameter and convention in the definition, test that only the owner can use recursive acquisition and ownership is relinquished exactly when matched release count reaches zero, compare the nearest accepted identity, and report counterexamples, uncertainty, and limiting cases.

Relationships to Other Abstractions

Current abstraction Reentrant mutex Domain-specific

Parents (1) — more general patterns this builds on

• Reentrant mutex is a kind of Coordination Prime

  The proposed strict upward parent is prime:coordination.

Hierarchy paths (5) — routes to 4 parentless roots

• Reentrant mutex → Coordination → Concurrency

Show alternative paths (4)

Neighborhood in Abstraction Space

Reentrant mutex sits in a moderately populated region (59^th percentile for distinctiveness): it has near-neighbors but no dense thicket of look-alikes.

Family — Concurrency, Transactions & Process Coordination (20 abstractions)

Nearest neighbors

• Thread-local storage — 0.88
• Running total — 0.87
• Shared memory — 0.87
• Thread pool — 0.87
• Unbounded nondeterminism — 0.87

Computed from structural-signature embeddings · 2026-09-08