_PyArg_Parser holds static global data generated for modules by Argument Clinic. The _PyArg_Parser.kwtuple field is a tuple object, even though it's stored within a static global. In some cases the tuple is statically allocated and thus it's okay that it gets shared by multiple interpreters. However, in other cases the tuple is set lazily, allocated from the heap using the active interprepreter at the point the tuple is needed.
This is a problem once that interpreter is destroyed since _PyArg_Parser.kwtuple becomes at dangling pointer, leading to crashes. It isn't a problem if the tuple is allocated under the main interpreter, since its lifetime is bound to the lifetime of the runtime. The solution here is to temporarily switch to the main interpreter. The alternative would be to always statically allocate the tuple.
This change also fixes a bug where only the most recent parser was added to the global linked list.
(cherry picked from commit 81865002ae)
We do the following:
* add a per-interpreter XID registry (PyInterpreterState.xidregistry)
* put heap types there (keep static types in _PyRuntimeState.xidregistry)
* clear the registries during interpreter/runtime finalization
* avoid duplicate entries in the registry (when _PyCrossInterpreterData_RegisterClass() is called more than once for a type)
* use Py_TYPE() instead of PyObject_Type() in _PyCrossInterpreterData_Lookup()
The per-interpreter registry helps preserve isolation between interpreters. This is important when heap types are registered, which is something we haven't been doing yet but I will likely do soon.
(cherry-picked from commit 80dc39e1dc)
The existence of background threads running on a subinterpreter was preventing interpreters from getting properly destroyed, as well as impacting the ability to run the interpreter again. It also affected how we wait for non-daemon threads to finish.
We add PyInterpreterState.threads.main, with some internal C-API functions.
(cherry-picked from commit 1dd9dee45d)
We tried this before with a dict and for all interned strings. That ran into problems due to interpreter isolation. However, exclusively using a per-interpreter cache caused some inconsistency that can eliminate the benefit of interning. Here we circle back to using a global cache, but only for statically allocated strings. We also use a more-basic _Py_hashtable_t for that global cache instead of a dict.
Ideally we would only have the global cache, but the optional isolation of each interpreter's allocator means that a non-static string object must not outlive its interpreter. Thus we would have to store a copy of each such interned string in the global cache, tied to the main interpreter.
(cherry-picked from commit b72947a8d2)
This change makes sure sys.path[0] is set properly for subinterpreters. Before, it wasn't getting set at all.
This change does not address the broader concerns from gh-109853.
(cherry-picked from commit a040a32ea2)
* GH-108390: Prevent non-local events being set with `sys.monitoring.set_local_events()` (GH-108420)
* Restore generated objects
* Restore size of monitoring arrays in code object for 3.12 ABI compatibility.
* Update ABI file
* gh-91051: fix segfault when using all 8 type watchers (GH-107853)
(cherry picked from commit 66e4edd734)
Co-authored-by: Carl Meyer <carl@oddbird.net>
gh-105699: Use a _Py_hashtable_t for the PyModuleDef Cache (gh-106974)
This fixes a crasher due to a race condition, triggered infrequently when two isolated (own GIL) subinterpreters simultaneously initialize their sys or builtins modules. The crash happened due the combination of the "detached" thread state we were using and the "last holder" logic we use for the GIL. It turns out it's tricky to use the same thread state for different threads. Who could have guessed?
We solve the problem by eliminating the one object we were still sharing between interpreters. We replace it with a low-level hashtable, using the "raw" allocator to avoid tying it to the main interpreter.
We also remove the accommodations for "detached" thread states, which were a dubious idea to start with.
(cherry picked from commit 8ba4df91ae)
gh-106140: Reorder some fields to facilitate out-of-process inspection (GH-106143)
(cherry picked from commit 2d5a1c2811)
Signed-off-by: Pablo Galindo <pablogsal@gmail.com>
Co-authored-by: Pablo Galindo Salgado <Pablogsal@gmail.com>
For a while now, pending calls only run in the main thread (in the main interpreter). This PR changes things to allow any thread run a pending call, unless the pending call was explicitly added for the main thread to run.
(cherry picked from commit 757b402)
The risk of a race with this state is relatively low, but we play it safe anyway. We do avoid using the lock in performance-sensitive cases where the risk of a race is very, very low.
(cherry picked from commit 68dfa49627)
Co-authored-by: Eric Snow <ericsnowcurrently@gmail.com>
The risk of a race with this state is relatively low, but we play it safe anyway.
(cherry picked from commit 7799c8e678)
Co-authored-by: Eric Snow <ericsnowcurrently@gmail.com>
In gh-103912 we added tp_bases and tp_mro to each PyInterpreterState.types.builtins entry. However, doing so ignored the fact that both PyTypeObject fields are public API, and not documented as internal (as opposed to tp_subclasses). We address that here by reverting back to shared objects, making them immortal in the process.
(cherry picked from commit 7be667d)
Co-authored-by: Eric Snow ericsnowcurrently@gmail.com
