Each thread specializes a thread-local copy of the bytecode, created on the first RESUME, in free-threaded builds. All copies of the bytecode for a code object are stored in the co_tlbc array on the code object. Threads reserve a globally unique index identifying its copy of the bytecode in all co_tlbc arrays at thread creation and release the index at thread destruction. The first entry in every co_tlbc array always points to the "main" copy of the bytecode that is stored at the end of the code object. This ensures that no bytecode is copied for programs that do not use threads.
Thread-local bytecode can be disabled at runtime by providing either -X tlbc=0 or PYTHON_TLBC=0. Disabling thread-local bytecode also disables specialization.
Concurrent modifications to the bytecode made by the specializing interpreter and instrumentation use atomics, with specialization taking care not to overwrite an instruction that was instrumented concurrently.
Temporarily ignore warnings about JIT deactivation when perf support is active.
This will be reverted as soon as a way is found to determine at run time whether the interpreter was built with JIT. Currently, this is not possible on Windows.
Co-authored-by: Kirill Podoprigora <kirill.bast9@mail.ru>
Co-authored-by: Ken Jin <28750310+Fidget-Spinner@users.noreply.github.com>
Co-authored-by: Pablo Galindo <pablogsal@gmail.com>
Previously, if the `ast.AST._fields` attribute was deleted, attempts to create a new `as`t node would crash due to the assumption that `_fields` always had a non-NULL value. Now it has been fixed by adding an extra check to ensure that `_fields` does not have a NULL value (this can happen when you manually remove `_fields` attribute).
* Remove `@suppress_immortalization` decorator
* Make suppression flag per-thread instead of per-interpreter
* Suppress immortalization in `eval()` to avoid refleaks in three tests
(test_datetime.test_roundtrip, test_logging.test_config8_ok, and
test_random.test_after_fork).
* frozenset() is constant, but not a singleton. When run multiple times,
the test could fail due to constant interning.
This replaces `_PyEval_BuiltinsFromGlobals` with
`_PyDict_LoadBuiltinsFromGlobals`, which returns a new reference
instead of a borrowed reference. Internally, the new function uses
per-thread reference counting when possible to avoid contention on the
refcount fields on the builtins module.
On Windows, `long` is a signed 32-bit integer so it can't represent
`0xffff_ffff` without overflow. Windows exit codes are unsigned 32-bit
integers, so if a child process exits with `-1`, it will be represented
as `0xffff_ffff`.
Also fix a number of other possible cases where `_Py_HandleSystemExit`
could return with an exception set, leading to a `SystemError` (or
fatal error in debug builds) later on during shutdown.
This fixes a crash when `gc.get_objects()` or `gc.get_referrers()` is
called during a GC in the free threading build.
Switch to `_PyObjectStack` to avoid corrupting the `struct worklist`
linked list maintained by the GC. Also, don't return objects that are frozen
(`gc.freeze()`) or in the process of being collected to more closely match
the behavior of the default build.
They used to be shared, before 3.12. Returning to sharing them resolves a failure on Py_TRACE_REFS builds.
Co-authored-by: Petr Viktorin <encukou@gmail.com>
* Fix usage of PyStackRef_FromPyObjectSteal in CALL_TUPLE_1
This was missed in gh-124894
* Fix usage of PyStackRef_FromPyObjectSteal in _CALL_STR_1
This was missed in gh-124894
* Regenerate code
This is essentially a cleanup, moving a handful of API declarations to the header files where they fit best, creating new ones when needed.
We do the following:
* add pycore_debug_offsets.h and move _Py_DebugOffsets, etc. there
* inline struct _getargs_runtime_state and struct _gilstate_runtime_state in _PyRuntimeState
* move struct _reftracer_runtime_state to the existing pycore_object_state.h
* add pycore_audit.h and move to it _Py_AuditHookEntry , _PySys_Audit(), and _PySys_ClearAuditHooks
* add audit.h and cpython/audit.h and move the existing audit-related API there
*move the perfmap/trampoline API from cpython/sysmodule.h to cpython/ceval.h, and remove the now-empty cpython/sysmodule.h
Users want to know when the current context switches to a different
context object. Right now this happens when and only when a context
is entered or exited, so the enter and exit events are synonymous with
"switched". However, if the changes proposed for gh-99633 are
implemented, the current context will also switch for reasons other
than context enter or exit. Since users actually care about context
switches and not enter or exit, replace the enter and exit events with
a single switched event.
The former exit event was emitted just before exiting the context.
The new switched event is emitted after the context is exited to match
the semantics users expect of an event with a past-tense name. If
users need the ability to clean up before the switch takes effect,
another event type can be added in the future. It is not added here
because YAGNI.
I skipped 0 in the enum as a matter of practice. Skipping 0 makes it
easier to troubleshoot when code forgets to set zeroed memory, and it
aligns with best practices for other tools (e.g.,
https://protobuf.dev/programming-guides/dos-donts/#unspecified-enum).
Co-authored-by: Richard Hansen <rhansen@rhansen.org>
Co-authored-by: Victor Stinner <vstinner@python.org>
Use per-thread refcounting for the reference from function objects to
their corresponding code object. This can be a source of contention when
frequently creating nested functions. Deferred refcounting alone isn't a
great fit here because these references are on the heap and may be
modified by other libraries.
This fixes a crash when running the PyO3 test suite on the free-threaded
build. The `qsbr` field is initialized after the `PyThreadState` is
added to the interpreter's linked list -- it might still be NULL.
Instead, we "steal" the queue of to-be-freed memory blocks. This is
always initialized (possibly empty) and protected by the stop the world
pause.
Users want to know when the current context switches to a different
context object. Right now this happens when and only when a context
is entered or exited, so the enter and exit events are synonymous with
"switched". However, if the changes proposed for gh-99633 are
implemented, the current context will also switch for reasons other
than context enter or exit. Since users actually care about context
switches and not enter or exit, replace the enter and exit events with
a single switched event.
The former exit event was emitted just before exiting the context.
The new switched event is emitted after the context is exited to match
the semantics users expect of an event with a past-tense name. If
users need the ability to clean up before the switch takes effect,
another event type can be added in the future. It is not added here
because YAGNI.
I skipped 0 in the enum as a matter of practice. Skipping 0 makes it
easier to troubleshoot when code forgets to set zeroed memory, and it
aligns with best practices for other tools (e.g.,
https://protobuf.dev/programming-guides/dos-donts/#unspecified-enum).
Peter Bierma