Fix memory leak in sub-interpreter creation caused by overwriting of the previously used `_malloced` field. Now the pointer is stored in the first word of the memory block to avoid it being overwritten accidentally.
Co-authored-by: Kumar Aditya <kumaraditya@python.org>
Fix memory leak in sub-interpreter creation caused by overwriting of the previously used `_malloced` field. Now the pointer is stored in the first word of the memory block to avoid it being overwritten accidentally.
Co-authored-by: Kumar Aditya <kumaraditya@python.org>
This partially reverts #137047, keeping the tests for GC collectability of the
original class that dataclass adds `__slots__` to.
The reference leaks solved there are instead solved by having the `__dict__` &
`__weakref__` descriptors not tied to (and referencing) their class.
Instead, they're shared between all classes that need them (within
an interpreter).
The `__objclass__` ol the descriptors is set to `object`, since these
descriptors work with *any* object. (The appropriate checks were already
made in the get/set code, so the `__objclass__` check was redundant.)
The repr of these descriptors (and any others whose `__objclass__` is `object`)
now doesn't mention the objclass.
This change required adjustment of introspection code that checks
`__objclass__` to determine an object's “own” (i.e. not inherited) `__dict__`.
Third-party code that does similar introspection of the internals will also
need adjusting.
Co-authored-by: Jelle Zijlstra <jelle.zijlstra@gmail.com>
There were a few thread-safety issues when profiling or tracing all
threads via PyEval_SetProfileAllThreads or PyEval_SetTraceAllThreads:
* The loop over thread states could crash if a thread exits concurrently
(in both the free threading and default build)
* The modification of `c_profilefunc` and `c_tracefunc` wasn't
thread-safe on the free threading build.
This commit fixes the following problems:
* The x86_64 trampolines are not preserving frame pointers
* The hardcoded offsets to the code segment from the FDE only worked properly for x64_64
* The CIE data was not following conventions of aarch64
* The eh_frame for aarch64 was not fully correct
* Replace _Py_ALIGN_AS(V) by _Py_ALIGNED_DEF(N, T)
This is now a common façade for the various `_Alignas` alternatives,
which behave in interesting ways -- see the source comment.
The new macro (and MSVC's `__declspec(align)`) should not be used
on a variable/member declaration that includes a struct declaraton.
A workaround is to separate the struct definition.
Do that for `PyASCIIObject.state`.
* Specify minimum PyGC_Head and PyObject alignment
As documented in InternalDocs/garbage_collector.md, the garbage collector
stores flags in the least significant two bits of the _gc_prev pointer
in struct PyGC_Head. Consequently, this pointer is only capable of storing
a location that's aligned to a 4-byte boundary.
Encode this requirement using _Py_ALIGNED_DEF.
This patch fixes a segfault in m68k, which was previously investigated
by Adrian Glaubitz here:
https://lists.debian.org/debian-68k/2024/11/msg00020.htmlhttps://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1087600
Original patch (using the GCC-only Py_ALIGNED) by Finn Thain.
Co-authored-by: Finn Thain <fthain@linux-m68k.org>
Co-authored-by: Victor Stinner <vstinner@python.org>
Co-authored-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
In the free-threaded build, avoid data races caused by updating type
slots or type flags after the type was initially created. For those
(typically rare) cases, use the stop-the-world mechanism. Remove the
use of atomics when reading or writing type flags.
Completely refactor Modules/_remote_debugging_module.c with improved
code organization, replacing scattered reference counting and error
handling with centralized goto error paths. This cleanup improves
maintainability and reduces code duplication throughout the module while
preserving the same external API.
Implement memory page caching optimization in Python/remote_debug.h to
avoid repeated reads of the same memory regions during debugging
operations. The cache stores previously read memory pages and reuses
them for subsequent reads, significantly reducing system calls and
improving performance.
Add code object caching mechanism with a new code_object_generation
field in the interpreter state that tracks when code object caches need
invalidation. This allows efficient reuse of parsed code object metadata
and eliminates redundant processing of the same code objects across
debugging sessions.
Optimize memory operations by replacing multiple individual structure
copies with single bulk reads for the same data structures. This reduces
the number of memory operations and system calls required to gather
debugging information from the target process.
Update Makefile.pre.in to include Python/remote_debug.h in the headers
list, ensuring that changes to the remote debugging header force proper
recompilation of dependent modules and maintain build consistency across
the codebase.
Also, make the module compatible with the free threading build as an extra :)
Co-authored-by: Łukasz Langa <lukasz@langa.pl>
For the free-threaded build, check the process resident set size (RSS)
increase before triggering a full automatic garbage collection. If the RSS
has not increased 10% since the last collection then it is deferred.
* Track the current executor, not the previous one, on the thread-state.
* Batch executors for deallocation to avoid having to constantly incref executors; this is an ad-hoc form of deferred reference counting.
In the free-threaded build, avoid data races caused by updating type slots
or type flags after the type was initially created. For those (typically
rare) cases, use the stop-the-world mechanism. Remove the use of atomics
when reading or writing type flags. The use of atomics is not sufficient to
avoid races (since flags are sometimes read without a lock and without
atomics) and are no longer required.
Make `warnings.catch_warnings()` use a context variable for holding
the warning filtering state if the `sys.flags.context_aware_warnings`
flag is set to true. This makes using the context manager thread-safe in
multi-threaded programs.
Add the `sys.flags.thread_inherit_context` flag. If true, starting a new
thread with `threading.Thread` will use a copy of the context
from the caller of `Thread.start()`.
Both these flags are set to true by default for the free-threaded build
and false for the default build.
Move the Python implementation of warnings.py into _py_warnings.py.
Make _contextvars a builtin module.
Co-authored-by: Kumar Aditya <kumaraditya@python.org>
Move pycore_obmalloc.h include from pycore_interp_structs.h to
pycore_runtime_structs.h.
Add also comment explaining the purpose of each include in
pycore_interp_structs.h, pycore_runtime_structs.h and
pycore_structs.h.
Remove <stdbool.h> and <stddef.h> from pycore_structs.h.
