- move the Py_Main documentation from the very high level API section
to the initialization and finalization section
- make it clear that it encapsulates a full Py_Initialize/Finalize
cycle of its own
- point out that exactly which settings will be read and applied
correctly when Py_Main is called after a separate runtime
initialization call is version dependent
- be explicit that Py_IsInitialized can be called prior to
initialization
- actually test that Py_IsInitialized can be called prior to
initialization
- flush stdout in the embedding tests that run code so it appears
in the expected order when running with "-vv"
- make "-vv" on the subinterpreter embedding tests less spammy
---------
Co-authored-by: Carol Willing <carolcode@willingconsulting.com>
In gh-121602, I applied a fix to a builtin types initialization bug.
That fix made sense in the context of some broader future changes,
but introduced a little bit of extra complexity. That fix has turned
out to be incomplete for some of the builtin types we haven't
been testing. I found that out while improving the tests.
A while back, @markshannon suggested a simpler fix that doesn't
have that problem, which I've already applied to 3.12 and 3.13.
I'm switching to that here. Given the potential long-term
benefits of the more complex (but still incomplete) approach,
I'll circle back to it in the future, particularly after I've improved
the tests so no corner cases slip through the cracks.
(This is effectively a "forward-port" of 716c677 from 3.13.)
Setting dev_mode to 1 in an isolated configuration now enables also
faulthandler.
Moreover, setting "module_search_paths" option with
PyInitConfig_SetStrList() now sets "module_search_paths_set" to 1.
Add PyConfig_Get(), PyConfig_GetInt(), PyConfig_Set() and
PyConfig_Names() functions to get and set the current runtime Python
configuration.
Add visibility and "sys spec" to config and preconfig specifications.
_PyConfig_AsDict() now converts PyConfig.xoptions as a dictionary.
Co-authored-by: Bénédikt Tran <10796600+picnixz@users.noreply.github.com>
Check that the current default heap is initialized in
`_mi_os_get_aligned_hint` and `mi_os_claim_huge_pages`.
The mimalloc function `_mi_os_get_aligned_hint` assumes that there is an
initialized default heap. This is true for our main thread, but not for
background threads. The problematic code path is usually called during
initialization (i.e., `Py_Initialize`), but it may also be called if the
program allocates large amounts of memory in total.
The crash only affected the free-threaded build.
There were a still a number of gaps in the tests, including not looking
at all the builtin types and not checking wrappers in subinterpreters
that weren't in the main interpreter. This fixes all that.
I considered incorporating the names of the PyTypeObject fields
(a la gh-122866), but figured doing so doesn't add much value.
The tests were only checking cases where the slot wrapper was present in the initial case. They were missing when the slot wrapper was added in the additional initializations. This fixes that.
On POSIX systems, excluding macOS framework installs, the lib directory
for the free-threaded build now includes a "t" suffix to avoid conflicts
with a co-located default build installation.
The _strptime module object was cached in a static local variable (in the datetime.strptime() implementation). That's a problem when it crosses isolation boundaries, such as reinitializing the runtme or between interpreters. This change fixes the problem by dropping the static variable, instead always relying on the normal sys.modules cache (via PyImport_Import()).
In free-threaded builds, running with `PYTHON_GIL=0` will now disable the
GIL. Follow-up issues track work to re-enable the GIL when loading an
incompatible extension, and to disable the GIL by default.
In order to support re-enabling the GIL at runtime, all GIL-related data
structures are initialized as usual, and disabling the GIL simply sets a flag
that causes `take_gil()` and `drop_gil()` to return early.
sys.audit() now has assertions to check that the event argument is
not NULL and that the format argument does not use the "N" format.
Add tests on PySys_AuditTuple().
This change makes sure sys.path[0] is set properly for subinterpreters. Before, it wasn't getting set at all. This PR does not address the broader concerns from gh-109853.
Statistics gathering is now off by default. Use the "-X pystats"
command line option or set the new PYTHONSTATS environment variable
to 1 to turn statistics gathering on at Python startup.
Statistics are no longer dumped at exit if statistics gathering was
off or statistics have been cleared.
Changes:
* Add PYTHONSTATS environment variable.
* sys._stats_dump() now returns False if statistics are not dumped
because they are all equal to zero.
* Add PyConfig._pystats member.
* Add tests on sys functions and on setting PyConfig._pystats to 1.
* Add Include/cpython/pystats.h and Include/internal/pycore_pystats.h
header files.
* Rename '_py_stats' variable to '_Py_stats'.
* Exclude Include/cpython/pystats.h from the Py_LIMITED_API.
* Move pystats.h include from object.h to Python.h.
* Add _Py_StatsOn() and _Py_StatsOff() functions. Remove
'_py_stats_struct' variable from the API: make it static in
specialize.c.
* Document API in Include/pystats.h and Include/cpython/pystats.h.
* Complete pystats documentation in Doc/using/configure.rst.
* Don't write "all zeros" stats: if _stats_off() and _stats_clear()
or _stats_dump() were called.
* _PyEval_Fini() now always call _Py_PrintSpecializationStats() which
does nothing if stats are all zeros.
Co-authored-by: Michael Droettboom <mdboom@gmail.com>
We also add PyInterpreterState.ceval.own_gil to record if the interpreter actually has its own GIL.
Note that for now we don't actually respect own_gil; all interpreters still share the one GIL. However, PyInterpreterState.ceval.own_gil does reflect PyInterpreterConfig.own_gil. That lie is a temporary one that we will fix when the GIL really becomes per-interpreter.
This PR makes some minor linting adjustments to the Lib/test module
caught by [ruff](https://github.com/charliermarsh/ruff). The adjustments
are all related to the `F541 f-string without any placeholders` issue.
Issue: https://github.com/python/cpython/issues/103805
<!-- gh-issue-number: gh-103805 -->
* Issue: gh-103805
<!-- /gh-issue-number -->
---------
Co-authored-by: blurb-it[bot] <43283697+blurb-it[bot]@users.noreply.github.com>
Co-authored-by: Gregory P. Smith <greg@krypto.org>
This is strictly about moving the "obmalloc" runtime state from
`_PyRuntimeState` to `PyInterpreterState`. Doing so improves isolation
between interpreters, specifically most of the memory (incl. objects)
allocated for each interpreter's use. This is important for a
per-interpreter GIL, but such isolation is valuable even without it.
FWIW, a per-interpreter obmalloc is the proverbial
canary-in-the-coalmine when it comes to the isolation of objects between
interpreters. Any object that leaks (unintentionally) to another
interpreter is highly likely to cause a crash (on debug builds at
least). That's a useful thing to know, relative to interpreter
isolation.
Enforcing (optionally) the restriction set by PEP 489 makes sense. Furthermore, this sets the stage for a potential restriction related to a per-interpreter GIL.
This change includes the following:
* add tests for extension module subinterpreter compatibility
* add _PyInterpreterConfig.check_multi_interp_extensions
* add Py_RTFLAGS_MULTI_INTERP_EXTENSIONS
* add _PyImport_CheckSubinterpIncompatibleExtensionAllowed()
* fail iff the module does not implement multi-phase init and the current interpreter is configured to check
https://github.com/python/cpython/issues/98627
Previously, the optional restrictions on subinterpreters were: disallow fork, subprocess, and threads. By default, we were disallowing all three for "isolated" interpreters. We always allowed all three for the main interpreter and those created through the legacy `Py_NewInterpreter()` API.
Those settings were a bit conservative, so here we've adjusted the optional restrictions to: fork, exec, threads, and daemon threads. The default for "isolated" interpreters disables fork, exec, and daemon threads. Regular threads are allowed by default. We continue always allowing everything For the main interpreter and the legacy API.
In the code, we add `_PyInterpreterConfig.allow_exec` and `_PyInterpreterConfig.allow_daemon_threads`. We also add `Py_RTFLAGS_DAEMON_THREADS` and `Py_RTFLAGS_EXEC`.
* As most of `test_embed` now uses `Py_InitializeFromConfig`, add
a specific test case to cover `Py_Initialize` (and `Py_InitializeEx`)
* Rename `_testembed` init helper to clarify the API used
* Add a `PyConfig_Clear` call in `Py_InitializeEx` to make
the code more obviously correct (it already didn't leak as
none of the dynamically allocated config fields were being
populated, but it's clearer if the wrappers follow the
documented API usage guidelines)
(see https://github.com/python/cpython/issues/98608)
This change does the following:
1. change the argument to a new `_PyInterpreterConfig` struct
2. rename the function to `_Py_NewInterpreterFromConfig()`, inspired by `Py_InitializeFromConfig()` (takes a `_PyInterpreterConfig` instead of `isolated_subinterpreter`)
3. split up the boolean `isolated_subinterpreter` into the corresponding multiple granular settings
* allow_fork
* allow_subprocess
* allow_threads
4. add `PyInterpreterState.feature_flags` to store those settings
5. add a function for checking if a feature is enabled on an opaque `PyInterpreterState *`
6. drop `PyConfig._isolated_interpreter`
The existing default (see `Py_NewInterpeter()` and `Py_Initialize*()`) allows fork, subprocess, and threads and the optional "isolated" interpreter (see the `_xxsubinterpreters` module) disables all three. None of that changes here; the defaults are preserved.
Note that the given `_PyInterpreterConfig` will not be used outside `_Py_NewInterpreterFromConfig()`, nor preserved. This contrasts with how `PyConfig` is currently preserved, used, and even modified outside `Py_InitializeFromConfig()`. I'd rather just avoid that mess from the start for `_PyInterpreterConfig`. We can preserve it later if we find an actual need.
This change allows us to follow up with a number of improvements (e.g. stop disallowing subprocess and support disallowing exec instead).
(Note that this PR adds "private" symbols. We'll probably make them public, and add docs, in a separate change.)
It had to live as a global outside of PyConfig for stable ABI reasons in
the pre-3.12 backports.
This removes the `_Py_global_config_int_max_str_digits` and gets rid of
the equivalent field in the internal `struct _is PyInterpreterState` as
code can just use the existing nested config struct within that.
Adds tests to verify unique settings and configs in subinterpreters.
⚠️⚠️ Note for reviewers, hackers and fellow systems/low-level/compiler engineers ⚠️⚠️
If you have a lot of experience with this kind of shenanigans and want to improve the **first** version, **please make a PR against my branch** or **reach out by email** or **suggest code changes directly on GitHub**.
If you have any **refinements or optimizations** please, wait until the first version is merged before starting hacking or proposing those so we can keep this PR productive.