Add a warning in the free-threading extensions howto explaining that
PyObject.ob_mutex is reserved for the critical section API and must not
be locked directly with PyMutex_Lock, as this can cause deadlocks.
Extension authors who need their own lock should add a separate PyMutex
field to their object struct.
Also add an ob_mutex member entry under PyObject in the C API reference
(Doc/c-api/structures.rst) with a cross-reference to the howto.
Co-authored-by: Victor Stinner <vstinner@python.org>
We already have a stop-the-world pause elsewhere in this code path
(type_set_bases) and this makes will make it easier to avoid contention
on the TYPE_LOCK when looking up names in the MRO hierarchy.
Also use deferred reference counting for non-immortal MROs.
Fix three issues that caused mimalloc pages to be leaked until the
owning thread exited:
1. In _PyMem_mi_page_maybe_free(), move pages out of the full queue
when relying on QSBR to defer freeing the page. Pages in the full
queue are never searched by mi_page_queue_find_free_ex(), so a page
left there is unusable for allocations.
2. Move _PyMem_mi_page_clear_qsbr() from _mi_page_free_collect() to
_mi_page_thread_free_collect() where it only fires when all blocks
on the page are free (used == 0). The previous placement was too
broad: it cleared QSBR state whenever local_free was non-NULL, but
_mi_page_free_collect() is called from non-allocation paths (e.g.,
page visiting in mi_heap_visit_blocks) where the page is not being
reused.
3. In _PyMem_mi_page_maybe_free(), use the page's heap tld to find the
correct thread state for QSBR list insertion instead of
PyThreadState_GET(). During stop-the-world pauses, the function may
process pages belonging to other threads, so the current thread
state is not necessarily the owner of the page.
Modifies the Emscripten build script to allow for custom cross-build directory
names, and to only clean Emscripten-specific paths (optionally including the
build python).
Co-authored-by: Russell Keith-Magee <russell@keith-magee.com>
* Match tutorial output to real interpreter output
* Avoid invalid escape sequence in example
Co-authored-by: Ned Batchelder <ned@nedbatchelder.com>
---------
Co-authored-by: Ned Batchelder <ned@nedbatchelder.com>
Add PyArg_ParseArray() and PyArg_ParseArrayAndKeywords()
functions to parse arguments of functions using the METH_FASTCALL
calling convention.
Co-authored-by: Bénédikt Tran <10796600+picnixz@users.noreply.github.com>
