Stowage/cpython
2
0
Fork 0
mirror of https://github.com/python/cpython.git synced 2025-12-08 06:10:17 +00:00
Code Issues Projects Releases Packages Wiki Activity

[3.14] gh-133296: Publicly expose critical section API that accepts PyMutex (gh-135899) (#136969)

Browse source 
Co-authored-by: Nathan Goldbaum <nathan.goldbaum@gmail.com>
Co-authored-by: Hugo van Kemenade <1324225+hugovk@users.noreply.github.com>
This commit is contained in:
Miss Islington (bot) 2025-07-22 11:44:59 +02:00 • committed by GitHub
parent ddd3413687
commit 11f510167c
No known key found for this signature in database
GPG key ID: B5690EEEBB952194
8 changed files with 96 additions and 15 deletions
Download patch file Download diff file Expand all files Collapse all files

40
Doc/c-api/init.rst
View file

@ -2458,6 +2458,12 @@ is resumed, and its locks reacquired. This means the critical section API
provides weaker guarantees than traditional locks -- they are useful because
their behavior is similar to the :term:`GIL`.
Variants that accept :c:type:`PyMutex` pointers rather than Python objects are also
available. Use these variants to start a critical section in a situation where
there is no :c:type:`PyObject` -- for example, when working with a C type that
does not extend or wrap :c:type:`PyObject` but still needs to call into the C
API in a manner that might lead to deadlocks.
The functions and structs used by the macros are exposed for cases
where C macros are not available. They should only be used as in the
given macro expansions. Note that the sizes and contents of the structures may
@ -2503,6 +2509,23 @@ code triggered by the finalizer blocks and calls :c:func:`PyEval_SaveThread`.
.. versionadded:: 3.13
.. c:macro:: Py_BEGIN_CRITICAL_SECTION_MUTEX(m)
Locks the mutex *m* and begins a critical section.
In the free-threaded build, this macro expands to::
{
PyCriticalSection _py_cs;
PyCriticalSection_BeginMutex(&_py_cs, m)
Note that unlike :c:macro:`Py_BEGIN_CRITICAL_SECTION`, there is no cast for
the argument of the macro - it must be a :c:type:`PyMutex` pointer.
On the default build, this macro expands to ``{``.
.. versionadded:: 3.14
.. c:macro:: Py_END_CRITICAL_SECTION()
Ends the critical section and releases the per-object lock.
@ -2532,6 +2555,23 @@ code triggered by the finalizer blocks and calls :c:func:`PyEval_SaveThread`.
.. versionadded:: 3.13
.. c:macro:: Py_BEGIN_CRITICAL_SECTION2_MUTEX(m1, m2)
Locks the mutexes *m1* and *m2* and begins a critical section.
In the free-threaded build, this macro expands to::
{
PyCriticalSection2 _py_cs2;
PyCriticalSection2_BeginMutex(&_py_cs2, m1, m2)
Note that unlike :c:macro:`Py_BEGIN_CRITICAL_SECTION2`, there is no cast for
the arguments of the macro - they must be :c:type:`PyMutex` pointers.
On the default build, this macro expands to ``{``.
.. versionadded:: 3.14
.. c:macro:: Py_END_CRITICAL_SECTION2()
Ends the critical section and releases the per-object locks.