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.
* The majority of the monitoring code is in instrumentation.c
* The new instrumentation bytecodes are in bytecodes.c
* legacy_tracing.c adapts the new API to the old sys.setrace and sys.setprofile APIs
I've also added a small comment to `Tools/c-analyzer/cpython/_parser.py` to trigger the `patchcheck` CI. It must pass now.
Automerge-Triggered-By: GH:ericsnowcurrently
The essentially eliminates the global variable, with the associated benefits. This is also a precursor to isolating this bit of state to PyInterpreterState.
Folks that currently read _Py_RefTotal directly would have to start using _Py_GetGlobalRefTotal() instead.
https://github.com/python/cpython/issues/102304
This will keep us from adding new unsupported (i.e. non-const) C global variables, which would break interpreter isolation.
FYI, historically it is very uncommon for new global variables to get added. Furthermore, it is rare for new code to break the c-analyzer. So the check should almost always pass unnoticed.
Note that I've removed test_check_c_globals. A test wasn't a great fit conceptually and was super slow on debug builds. A CI check is a better fit.
This also resolves gh-100237.
https://github.com/python/cpython/issues/81057
distutils was removed in November. However, the c-analyzer relies on it. To solve that here, we vendor the parts the tool needs so it can be run against 3.12+. (Also see gh-92584.)
Note that we may end up removing this code later in favor of a solution in common with the peg_generator tool (which also relies on distutils). At the least, the copy here makes sure the c-analyzer tool works on 3.12+ in the meantime.
Some incompatible changes had gone in, and the "ignore" lists weren't properly undated. This change fixes that. It's necessary prior to enabling test_check_c_globals, which I hope to do soon.
Note that this does include moving last_resort_memory_error to PyInterpreterState.
https://github.com/python/cpython/issues/90110
We can't move it to _PyRuntimeState because the symbol is exposed in the stable ABI. We'll have to sort that out before a per-interpreter GIL, but it shouldn't be too hard.
https://github.com/python/cpython/issues/81057
This is part of the effort to consolidate global variables, to make them easier to manage (and make it easier to later move some of them to PyInterpreterState).
https://github.com/python/cpython/issues/81057
We actually don't move PyImport_Inittab. Instead, we make a copy that we keep on _PyRuntimeState and use only that after Py_Initialize(). We also prevent folks from modifying PyImport_Inittab (the best we can) after that point.
https://github.com/python/cpython/issues/81057
The global allocators were stored in 3 static global variables: _PyMem_Raw, _PyMem, and _PyObject. State for the "small block" allocator was stored in another 13. That makes a total of 16 global variables. We are moving all 16 to the _PyRuntimeState struct as part of the work for gh-81057. (If PEP 684 is accepted then we will follow up by moving them all to PyInterpreterState.)
https://github.com/python/cpython/issues/81057