Upgrade threading to 3.13.11; sys.setprofile & impl more threading by youknowone · Pull Request #6691 · RustPython/RustPython

youknowone

112-112: LGTM: Module attributes and Lock constructor updated correctly.

The module attribute changes to "_thread" align with Python's standard library naming, and the Lock constructor correctly initializes with RawMutex::INIT. The parameter rename to _vm follows Rust conventions for unused parameters.

Also applies to: 176-177, 190-190

402-434: LGTM: Thread management functions implemented correctly.

The new functions provide essential threading APIs:

daemon_threads_allowed and _is_main_interpreter return appropriate constants for RustPython's single-interpreter model
_shutdown is correctly stubbed as cleanup happens via the Thread class
_make_thread_handle properly creates a handle for an existing thread
_get_main_thread_ident provides access to the main thread identifier

436-443: LGTM: Main thread identifier storage implemented correctly.

The use of AtomicCell<u64> ensures thread-safe access to the main thread identifier. The initialization logic correctly captures the current thread's ID.

577-596: LGTM: Thread-local cleanup mechanism implemented correctly.

The LocalGuard with Weak reference ensures proper cleanup of thread-local data when threads terminate, while avoiding circular references that would prevent cleanup. The Drop implementation correctly checks if the LocalData still exists before attempting removal.

598-607: LGTM: LocalData structure is well-designed.

The structure uses parking_lot::Mutex to protect a HashMap mapping thread IDs to per-thread dictionaries, providing an efficient thread-local storage implementation.

610-665: Excellent implementation of thread-local storage with proper synchronization.

The Local::l_dict implementation uses an efficient double-checked locking pattern:

Fast path checks for existing dict under lock
Slow path allocates outside lock to reduce contention
Uses Entry API to handle races correctly
Explicitly drops lock before TLS access to avoid potential deadlocks
Guards registered only for new entries

This is a well-thought-out design that minimizes lock contention while ensuring correctness.

710-736: LGTM: Thread handle state machine and internal structure are well-designed.

The ThreadHandleState enum defines a clear lifecycle (NotStarted → Starting → Running → Done), and ThreadHandleInner tracks all necessary state including the join handle and a joined flag for idempotent join operations.

738-772: LGTM: ThreadHandle accessors and constructors are correctly implemented.

The new(), ident(), is_done(), _set_done(), and slot_new() methods properly manage the thread handle state with appropriate locking.

Also applies to: 810-816

818-827: LGTM: StartJoinableThreadArgs structure is well-defined.

The arguments structure correctly captures the function to execute, an optional pre-created handle, and a daemon flag (currently unused but allowed for future use).

3-3: The init_main_thread_ident function is properly called during VM initialization at crates/vm/src/vm/mod.rs:310, before other stdlib modules are initialized. The initialization is correctly guarded by the threading feature flag and properly captures the main thread identifier.