* gh-112532: Use separate mimalloc heaps for GC objects
In `--disable-gil` builds, we now use four separate heaps in
anticipation of using mimalloc to find GC objects when the GIL is
disabled. To support this, we also make a few changes to mimalloc:
* `mi_heap_t` and `mi_tld_t` initialization is split from allocation.
This allows us to have a `mi_tld_t` per-`PyThreadState`, which is
important to keep interpreter isolation, since the same OS thread may
run in multiple interpreters (using different PyThreadStates.)
* Heap abandoning (mi_heap_collect_ex) can now be called from a
different thread than the one that created the heap. This is necessary
because we may clear and delete the containing PyThreadStates from a
different thread during finalization and after fork().
* Use enum instead of defines and guard mimalloc includes.
* The enum typedef will be convenient for future PRs that use the type.
* Guarding the mimalloc includes allows us to unconditionally include
pycore_mimalloc.h from other header files that rely on things like
`struct _mimalloc_thread_state`.
* Only define _mimalloc_thread_state in Py_GIL_DISABLED builds
Fix error check on mmap(2)
It should check MAP_FAILED instead of NULL for error.
On mmap(2) man page:
RETURN VALUE
On success, mmap() returns a pointer to the mapped area.
On error, the value MAP_FAILED (that is, (void *) -1) is
returned, and errno is set to indicate the error.
It was raised in two cases:
* in the import statement when looking up __import__
* in pickling some builtin type when looking up built-ins iter, getattr, etc.
We need the TracebackException of uncaught exceptions for a single purpose: the error display. Thus we only need to pass the formatted error display between interpreters. Passing a pickled TracebackException is overkill.
The `PyThreadState_Clear()` function must only be called with the GIL
held and must be called from the same interpreter as the passed in
thread state. Otherwise, any Python objects on the thread state may be
destroyed using the wrong interpreter, leading to memory corruption.
This is also important for `Py_GIL_DISABLED` builds because free lists
will be associated with PyThreadStates and cleared in
`PyThreadState_Clear()`.
This fixes two places that called `PyThreadState_Clear()` from the wrong
interpreter and adds an assertion to `PyThreadState_Clear()`.
When an exception is uncaught in Interpreter.exec_sync(), it helps to show that exception's error display if uncaught in the calling interpreter. We do so here by generating a TracebackException in the subinterpreter and passing it between interpreters using pickle.
This fixes a recently introduced bug where the deferred count is being unnecessarily decremented to counteract an increment elsewhere that is no longer happening. This caused the values to flip around to "very large" 64-bit numbers.
glibc-2.34 implements closefrom(3) using the same semantics as on BSD.
Check for closefrom() in configure and use the check result in
fileutils.c, rather than hardcoding a FreeBSD check.
Some implementations of closefrom() return an int. Explicitly discard
the return value by casting it to void, to avoid future compiler
warnings.
Signed-off-by: Sam James <sam@gentoo.org>
This replaces some usages of PyThread_type_lock with PyMutex, which does not require memory allocation to initialize.
This simplifies some of the runtime initialization and is also one step towards avoiding changing the default raw memory allocator during initialize/finalization, which can be non-thread-safe in some circumstances.
Every PyThreadState instance is now actually a _PyThreadStateImpl.
It is safe to cast from `PyThreadState*` to `_PyThreadStateImpl*` and back.
The _PyThreadStateImpl will contain fields that we do not want to expose
in the public C API.
This updates `dtoa.c` to avoid using the Bigint free-list in --disable-gil builds and
to pre-computes the needed powers of 5 during interpreter initialization.
* gh-111962: Make dtoa thread-safe in `--disable-gil` builds.
This avoids using the Bigint free-list in `--disable-gil` builds
and pre-computes the needed powers of 5 during interpreter initialization.
* Fix size of cached powers of 5 array.
We need the powers of 5 up to 5**512 because we only jump straight to
underflow when the exponent is less than -512 (or larger than 308).
* Rename Py_NOGIL to Py_GIL_DISABLED
* Changes from review
* Fix assertion placement
If the input prompt to the builtin input function on terminal has any null
character, then raise ValueError instead of silently truncating it.
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
Previously arbitrary errors could be cleared during formatting error
messages for ImportError or AttributeError for modules. Now all
unexpected errors are reported.
* Implement _Py_HashPointerRaw() as a static inline function.
* Add Py_HashPointer() tests to test_capi.test_hash.
* Keep _Py_HashPointer() function as an alias to Py_HashPointer().
Change the declaration of the keywords parameter in functions
PyArg_ParseTupleAndKeywords() and PyArg_VaParseTupleAndKeywords() from `char **`
to `char * const *` in C and `const char * const *` in C++.
It makes these functions compatible with argument of type `const char * const *`,
`const char **` or `char * const *` in C++ and `char * const *` in C
without explicit type cast.
Co-authored-by: C.A.M. Gerlach <CAM.Gerlach@Gerlach.CAM>
Use a fraction internally in the _PyTime API to reduce the risk of
integer overflow: simplify the fraction using Greatest Common
Divisor (GCD). The fraction API is used by time functions:
perf_counter(), monotonic() and process_time().
For example, QueryPerformanceFrequency() usually returns 10 MHz on
Windows 10 and newer. The fraction SEC_TO_NS / frequency =
1_000_000_000 / 10_000_000 can be simplified to 100 / 1.
* Add _PyTimeFraction type.
* Add functions:
* _PyTimeFraction_Set()
* _PyTimeFraction_Mul()
* _PyTimeFraction_Resolution()
* No longer check "numer * denom <= _PyTime_MAX" in
_PyTimeFraction_Set(). _PyTimeFraction_Mul() uses _PyTime_Mul()
which handles integer overflow.
* Move _PyRuntimeState.time to _posixstate.ticks_per_second and
time_module_state.ticks_per_second.
* Add time_module_state.clocks_per_second.
* Rename _PyTime_GetClockWithInfo() to py_clock().
* Rename _PyTime_GetProcessTimeWithInfo() to py_process_time().
* Add process_time_times() helper function, called by
py_process_time().
* os.times() is now always built: no longer rely on HAVE_TIMES.
This makes the Tier 2 interpreter a little faster.
I calculated by about 3%,
though I hesitate to claim an exact number.
This starts by doubling the trace size limit (to 512),
making it more likely that loops fit in a trace.
The rest of the approach is to only load
`oparg` and `operand` in cases that use them.
The code generator know when these are used.
For `oparg`, it will conditionally emit
```
oparg = CURRENT_OPARG();
```
at the top of the case block.
(The `oparg` variable may be referenced multiple times
by the instructions code block, so it must be in a variable.)
For `operand`, it will use `CURRENT_OPERAND()` directly
instead of referencing the `operand` variable,
which no longer exists.
(There is only one place where this will be used.)
This uses the new mechanism whereby certain uops
are replaced by others during translation,
using the `_PyUop_Replacements` table.
We further special-case the `_FOR_ITER_TIER_TWO` uop
to update the deoptimization target to point
just past the corresponding `END_FOR` opcode.
Two tiny code cleanups are also part of this PR.
- Ensure that `assert(type_version != 0);` always comes *before* using `type_version`
Also:
- In cases_generator, rename `-v` to from `--verbose` to `--viable`
- Double max trace size to 256
- Add a dependency on executor_cases.c.h for ceval.o
- Mark `_SPECIALIZE_UNPACK_SEQUENCE` as `TIER_ONE_ONLY`
- Add debug output back showing the optimized trace
- Bunch of cleanups to Tools/cases_generator/
* Replace jumps with deopts in tier 2
* Fewer special cases of uop names
* Add target field to uop IR
* Remove more redundant SET_IP and _CHECK_VALIDITY micro-ops
* Extend whitelist of non-escaping API functions.
_PyDict_Pop_KnownHash(): remove the default value and the return type
becomes an int.
Co-authored-by: Stefan Behnel <stefan_ml@behnel.de>
Co-authored-by: Antoine Pitrou <pitrou@free.fr>
In PGO mode, this function caused a compiler error in MSVC.
It turns out that optimizing for space only save the day, and is even faster.
However, without PGO, this is neither necessary nor slower.
Critical sections are helpers to replace the global interpreter lock
with finer grained locking. They provide similar guarantees to the GIL
and avoid the deadlock risk that plain locking involves. Critical
sections are implicitly ended whenever the GIL would be released. They
are resumed when the GIL would be acquired. Nested critical sections
behave as if the sections were interleaved.
* Revert "gh-111089: Use PyUnicode_AsUTF8() in Argument Clinic (#111585)"
This reverts commit d9b606b3d0.
* Revert "gh-111089: Use PyUnicode_AsUTF8() in getargs.c (#111620)"
This reverts commit cde1071b2a.
* Revert "gh-111089: PyUnicode_AsUTF8() now raises on embedded NUL (#111091)"
This reverts commit d731579bfb.
* Revert "gh-111089: Add PyUnicode_AsUTF8() to the limited C API (#111121)"
This reverts commit d8f32be5b6.
* Revert "gh-111089: Use PyUnicode_AsUTF8() in sqlite3 (#111122)"
This reverts commit 37e4e20eaa.
I added _Py_excinfo to the internal API (and added its functions in Python/errors.c) in gh-111530 (9322ce9). Since then I've had a nagging sense that I should have added the type and functions in its own PR. While I do plan on using _Py_excinfo outside crossinterp.c very soon (see gh-111572/gh-111573), I'd still feel more comfortable if the _Py_excinfo stuff went in as its own PR. Hence, here we are.
(FWIW, I may combine that with gh-111572, which I may, in turn, combine with gh-111573. We'll see.)
Joining a thread now ensures the underlying OS thread has exited. This is required for safer fork() in multi-threaded processes.
---------
Co-authored-by: blurb-it[bot] <43283697+blurb-it[bot]@users.noreply.github.com>
Replace most of calls of _PyErr_WriteUnraisableMsg() and some
calls of PyErr_WriteUnraisable(NULL) with PyErr_FormatUnraisable().
Co-authored-by: Victor Stinner <vstinner@python.org>
This moves several general internal APIs out of _xxsubinterpretersmodule.c and into the new Python/crossinterp.c (and the corresponding internal headers).
Specifically:
* _Py_excinfo, etc.: the initial implementation for non-object exception snapshots (in pycore_pyerrors.h and Python/errors.c)
* _PyXI_exception_info, etc.: helpers for passing an exception beween interpreters (wraps _Py_excinfo)
* _PyXI_namespace, etc.: helpers for copying a dict of attrs between interpreters
* _PyXI_Enter(), _PyXI_Exit(): functions that abstract out the transitions between one interpreter and a second that will do some work temporarily
Again, these were all abstracted out of _xxsubinterpretersmodule.c as generalizations. I plan on proposing these as public API at some point.
- There is no longer a separate Python/executor.c file.
- Conventions in Python/bytecodes.c are slightly different -- don't use `goto error`,
you must use `GOTO_ERROR(error)` (same for others like `unused_local_error`).
- The `TIER_ONE` and `TIER_TWO` symbols are only valid in the generated (.c.h) files.
- In Lib/test/support/__init__.py, `Py_C_RECURSION_LIMIT` is imported from `_testcapi`.
- On Windows, in debug mode, stack allocation grows from 8MiB to 12MiB.
- **Beware!** This changes the env vars to enable uops and their debugging
to `PYTHON_UOPS` and `PYTHON_LLTRACE`.
Replace PyUnicode_AsUTF8AndSize() with PyUnicode_AsUTF8() to remove
the explicit check for embedded null characters.
The change avoids to have to include explicitly <string.h> to get the
strlen() function when using a recent version of the limited C API.
This is partly to clear this stuff out of pystate.c, but also in preparation for moving some code out of _xxsubinterpretersmodule.c. This change also moves this stuff to the internal API (new: Include/internal/pycore_crossinterp.h). @vstinner did this previously and I undid it. Now I'm re-doing it. :/
* gh-106320: Re-add _PyLong_FromByteArray(), _PyLong_AsByteArray() and _PyLong_GCD() to the public header files since they are used by third-party packages and there is no efficient replacement.
See https://github.com/python/cpython/issues/111140
See https://github.com/python/cpython/issues/111139
* gh-111262: Re-add _PyDict_Pop() to have a C-API until a new public one is designed.
There were a few things I did in gh-110565 that need to be fixed. I also forgot to add tests in that PR.
(Note that this PR exposes a refleak introduced by gh-110246. I'll take care of that separately.)
Move the following private functions and structures to
pycore_modsupport.h internal C API:
* _PyArg_BadArgument()
* _PyArg_CheckPositional()
* _PyArg_NoKeywords()
* _PyArg_NoPositional()
* _PyArg_ParseStack()
* _PyArg_ParseStackAndKeywords()
* _PyArg_Parser structure
* _PyArg_UnpackKeywords()
* _PyArg_UnpackKeywordsWithVararg()
* _PyArg_UnpackStack()
* _Py_ANY_VARARGS()
Changes:
* Python/getargs.h now includes pycore_modsupport.h to export
functions.
* clinic.py now adds pycore_modsupport.h when one of these functions
is used.
* Add pycore_modsupport.h includes when a C extension uses one of
these functions.
* Define Py_BUILD_CORE_MODULE in C extensions which now include
directly or indirectly (via code generated by Argument Clinic)
pycore_modsupport.h:
* _csv
* _curses_panel
* _dbm
* _gdbm
* _multiprocessing.posixshmem
* _sqlite.row
* _statistics
* grp
* resource
* syslog
* _testcapi: bad_get() no longer uses METH_FASTCALL calling
convention but METH_VARARGS. Replace _PyArg_UnpackStack() with
PyArg_ParseTuple().
* _testcapi: add PYTESTCAPI_NEED_INTERNAL_API macro which is defined
by _testcapi sub-modules which need the internal C API
(pycore_modsupport.h): exceptions.c, float.c, vectorcall.c,
watchers.c.
* Remove Include/cpython/modsupport.h header file.
Include/modsupport.h no longer includes the removed header file.
* Fix mypy clinic.py