Skip to content

gh-138115: Move stackref buffer to thread state to reduce interp stack usage #138116

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Closed
wants to merge 2 commits into from
Closed

gh-138115: Move stackref buffer to thread state to reduce interp stack usage #138116

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
988cb27
Move stackref buffer to thread state to reduce interp stack usage
Fidget-Spinner Aug 24, 2025
e1702fd
oopsie
Fidget-Spinner Aug 24, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
7 changes: 7 additions & 0 deletions Include/internal/pycore_tstate.h
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -21,6 +21,10 @@ struct _gc_thread_state {
};
#endif

/* How much scratch space to give stackref to PyObject* conversion. */
#define MAX_STACKREF_SCRATCH 10


// Every PyThreadState is actually allocated as a _PyThreadStateImpl. The
// PyThreadState fields are exposed as part of the C API, although most fields
// are intended to be private. The _PyThreadStateImpl fields not exposed.
Expand All @@ -47,6 +51,9 @@ typedef struct _PyThreadStateImpl {
struct _qsbr_thread_state *qsbr; // only used by free-threaded build
struct llist_node mem_free_queue; // delayed free queue

// Scratch space to convert _PyStackRef to PyObject *
// +1 to account for possible vectorcalls.
PyObject *stackref_scratch[MAX_STACKREF_SCRATCH + 1];
#ifdef Py_GIL_DISABLED
// Stack references for the current thread that exist on the C stack
struct _PyCStackRef *c_stack_refs;
Expand Down
6 changes: 2 additions & 4 deletions Python/ceval_macros.h
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -390,12 +390,10 @@ do { \

/* Stackref macros */

/* How much scratch space to give stackref to PyObject* conversion. */
#define MAX_STACKREF_SCRATCH 10

#define STACKREFS_TO_PYOBJECTS(ARGS, ARG_COUNT, NAME) \
/* +1 because vectorcall might use -1 to write self */ \
PyObject *NAME##_temp[MAX_STACKREF_SCRATCH+1]; \
_PyThreadStateImpl *_tstate = (_PyThreadStateImpl *)tstate; \
PyObject **NAME##_temp = _tstate->stackref_scratch; \
PyObject **NAME = _PyObjectArray_FromStackRefArray(ARGS, ARG_COUNT, NAME##_temp + 1);

#define STACKREFS_TO_PYOBJECTS_CLEANUP(NAME) \
Expand Down
Loading