mirrors/cpython
1
0
Fork 0
mirror of https://github.com/python/cpython.git synced 2025-08-31 14:07:50 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 9

gh-101659: Isolate "obmalloc" State to Each Interpreter (gh-101660)

Browse source 
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.
This commit is contained in:
Eric Snow 2023-04-24 17:23:57 -06:00 • committed by GitHub
parent 01be52e42e
commit df3173d28e
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
20 changed files with 322 additions and 73 deletions
Download patch file Download diff file Expand all files Collapse all files

17
Python/pystate.c
View file

@ -671,6 +671,14 @@ init_interpreter(PyInterpreterState *interp,
assert(next != NULL || (interp == runtime->interpreters.main));
interp->next = next;
/* Initialize obmalloc, but only for subinterpreters,
since the main interpreter is initialized statically. */
if (interp != &runtime->_main_interpreter) {
poolp temp[OBMALLOC_USED_POOLS_SIZE] = \
_obmalloc_pools_INIT(interp->obmalloc.pools);
memcpy(&interp->obmalloc.pools.used, temp, sizeof(temp));
}
_PyEval_InitState(&interp->ceval, pending_lock);
_PyGC_InitState(&interp->gc);
PyConfig_InitPythonConfig(&interp->config);
@ -941,11 +949,12 @@ PyInterpreterState_Delete(PyInterpreterState *interp)
_PyEval_FiniState(&interp->ceval);
#ifdef Py_REF_DEBUG
// XXX This call should be done at the end of clear_interpreter(),
// XXX These two calls should be done at the end of clear_interpreter(),
// but currently some objects get decref'ed after that.
#ifdef Py_REF_DEBUG
_PyInterpreterState_FinalizeRefTotal(interp);
#endif
_PyInterpreterState_FinalizeAllocatedBlocks(interp);
HEAD_LOCK(runtime);
PyInterpreterState **p;
@ -2320,11 +2329,11 @@ _PyCrossInterpreterData_InitWithSize(_PyCrossInterpreterData *data,
// where it was allocated, so the interpreter is required.
assert(interp != NULL);
_PyCrossInterpreterData_Init(data, interp, NULL, obj, new_object);
data->data = PyMem_Malloc(size);
data->data = PyMem_RawMalloc(size);
if (data->data == NULL) {
return -1;
}
data->free = PyMem_Free;
data->free = PyMem_RawFree;
return 0;
}