Fix huge page leak in datastack chunk allocator
The original fix rounded datastack chunk allocations in pystate.c so that
_PyObject_VirtualFree() would receive the full huge page mapping size.
Change direction and move that logic into _PyObject_VirtualAlloc() and
_PyObject_VirtualFree() instead. The key invariant is that munmap() must see
the full mapped size, so alloc and free now apply the same platform-specific
rounding in the allocator layer.
This keeps _PyStackChunk bookkeeping in requested-size units, avoids a
hardcoded 2 MB assumption, and also covers other small virtual-memory users
such as the JIT tracer state allocation in optimizer.c.
When Python is built in debug mode:
* long_alloc() now initializes digits with a pattern to detect usage of
uninitialized digits.
* _PyLong_CompactValue() now makes sure that the digit is zero when the
sign is zero.
* PyLongWriter_Finish() now raises SystemError if it detects uninitialized
digits
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
With this we can assume, that _PyLong_SetSignAndDigitCount() and
_PyLong_SetDigitCount() operate on non-immortal integers.
Co-authored-by: Victor Stinner <vstinner@python.org>
Accepted range for the bytes_per_sep argument of bytes.hex(),
bytearray.hex(), memoryview.hex(), and binascii.b2a_hex()
is now increased, so passing sys.maxsize and -sys.maxsize is now
valid.
The long_from_string_base() might return a small integer, when the
_pylong.py is used to do conversion. Hence, we must be careful here to
not smash it "small int" bit by using the _PyLong_FlipSign().
Co-authored-by: Victor Stinner <vstinner@python.org>
This reverts commit 68c7fad757.
It looks like on practice the __STDC_IEC_559__ doesn't indicate
conformance to the standard. It can't be used to filter out tests
or to give some promises in documentation. See discussion in
the reverted PR thread:
https://github.com/python/cpython/pull/138811#issuecomment-4117692418
Fix free-threading scaling bottleneck in sys.intern and `PyObject_SetAttr` by
avoiding the interpreter-wide lock when the string is already interned and
immortalized.
Rename from _Py_INTERNAL_ABI_SLOT to _Py_ABI_SLOT
and define the macro using _PyABIInfo_DEFAULT.
Use the ABI slot in stdlib extension modules to enable running
a check of ABI version compatibility.
_tkinter, _tracemalloc and readline don't use the slots, hence they need
explicit handling.
Co-authored-by: Victor Stinner <vstinner@python.org>
This value indicating support the IEC 60559 floating-point standard (the
Annex F of C99). If enabled, the float type characteristics matches the
IEC 60559 double format and exceptional cases for the math's functions
follow to the section F.10 of the C99 standard.
Co-authored-by: Victor Stinner <vstinner@python.org>
Co-authored-by: Stan Ulbrych <89152624+StanFromIreland@users.noreply.github.com>
Add special cases for classmethod and staticmethod descriptors in
_PyObject_GetMethodStackRef() to avoid calling tp_descr_get, which
avoids reference count contention on the bound method and underlying
callable. This improves scaling when calling classmethods and
staticmethods from multiple threads.
Also refactor method_vectorcall in classobject.c into a new _PyObject_VectorcallPrepend() helper so that it can be used by
PyObject_VectorcallMethod as well.
* Add the c_init_default attribute which is used to initialize the C variable
if the default is not explicitly provided.
* Add the c_default_init() method which is used to derive c_default from
default if c_default is not explicitly provided.
* Explicit c_default and py_default are now almost always have precedence
over the generated value.
* Add support for bytes literals as default values.
* Improve support for str literals as default values (support non-ASCII
and non-printable characters and special characters like backslash or quotes).
* Fix support for str and bytes literals containing trigraphs, "/*" and "*/".
* Improve support for default values in converters "char" and "int(accept={str})".
* Converter "int(accept={str})" now requires 1-character string instead of
integer as default value.
* Add support for non-None default values in converter "Py_buffer": NULL,
str and bytes literals.
* Improve error handling for invalid default values.
* Rename Null to NullType for consistency.
Setting the size to 0 turns the list contents into overallocated memory that the deallocator will free.
Ownership is transferred to the new tuple so no refcount adjustment is needed.
* Drop DOUBLE_IS_ARM_MIXED_ENDIAN_IEEE754 macro.
* Use DOUBLE_IS_BIG/LITTLE_ENDIAN_IEEE754 to detect endianness of
float/doubles.
* Drop "unknown_format" code path in PyFloat_Pack/Unpack*().
Co-authored-by: Victor Stinner <vstinner@python.org>
