GeezerVison

Original file line number	Diff line number	Diff line change
Expand Up		@@ -93,6 +93,13 @@ Other Language Changes
		when parsing source code containing null bytes. (Contributed by Pablo Galindo
		in :gh:`96670`.)

		* The Garbage Collector now runs only on the eval breaker mechanism of the
		Python bytecode evaluation loop instead on object allocations. The GC can
		also run when :c:func:`PyErr_CheckSignals` is called so C extensions that
		need to run for a long time without executing any Python code also have a
		chance to execute the GC periodically. (Contributed by Pablo Galindo in
		:gh:`97922`.)

		New Modules
		===========

Expand Down

2 changes: 2 additions & 0 deletions 2 Include/internal/pycore_gc.h

Show comments

View file

Open in desktop

Original file line number	Diff line number	Diff line change
Expand Up		@@ -202,6 +202,8 @@ extern void _PyList_ClearFreeList(PyInterpreterState *interp);
		extern void _PyDict_ClearFreeList(PyInterpreterState *interp);
		extern void _PyAsyncGen_ClearFreeLists(PyInterpreterState *interp);
		extern void _PyContext_ClearFreeList(PyInterpreterState *interp);
		extern void _Py_ScheduleGC(PyInterpreterState *interp);
		extern void _Py_RunGC(PyThreadState *tstate);

		#ifdef __cplusplus
		}
Expand Down

2 changes: 2 additions & 0 deletions 2 Include/internal/pycore_interp.h

Show comments

View file

Open in desktop

Original file line number	Diff line number	Diff line change
Expand Up		@@ -49,6 +49,8 @@ struct _ceval_state {
		_Py_atomic_int eval_breaker;
		/* Request for dropping the GIL */
		_Py_atomic_int gil_drop_request;
		/* The GC is ready to be executed */
		_Py_atomic_int gc_scheduled;
		struct _pending_calls pending;
		};

Expand Down

2 changes: 1 addition & 1 deletion 2 Lib/test/test_frame.py

Show comments

View file

Open in desktop

Original file line number	Diff line number	Diff line change
Expand Up		@@ -277,7 +277,7 @@ def callback(phase, info):
		frame!
		"""
		nonlocal sneaky_frame_object
		sneaky_frame_object = sys._getframe().f_back
		sneaky_frame_object = sys._getframe().f_back.f_back
		# We're done here:
		gc.callbacks.remove(callback)

Expand Down

5 changes: 5 additions & 0 deletions 5 Misc/NEWS.d/next/Core and Builtins/2022-10-05-11-37-15.gh-issue-97922.Zu9Bge.rst

Show comments

View file

Open in desktop

Original file line number	Diff line number	Diff line change
		@@ -0,0 +1,5 @@
		The Garbage Collector now runs only on the eval breaker mechanism of the
		Python bytecode evaluation loop instead on object allocations. The GC can
		also run when :c:func:`PyErr_CheckSignals` is called so C extensions that
		need to run for a long time without executing any Python code also have a
		chance to execute the GC periodically.

27 changes: 24 additions & 3 deletions 27 Modules/gcmodule.c

Show comments

View file

Open in desktop

Original file line number	Diff line number	Diff line change
Expand Up		@@ -2252,6 +2252,20 @@ PyObject_IS_GC(PyObject *obj)
		return _PyObject_IS_GC(obj);
		}

		void
		_Py_ScheduleGC(PyInterpreterState *interp)
		{
		GCState *gcstate = &interp->gc;
		if (gcstate->collecting == 1) {
		return;
		}
		struct _ceval_state *ceval = &interp->ceval;
		if (!_Py_atomic_load_relaxed(&ceval->gc_scheduled)) {
		_Py_atomic_store_relaxed(&ceval->gc_scheduled, 1);
		_Py_atomic_store_relaxed(&ceval->eval_breaker, 1);
		}
		}

		void
		_PyObject_GC_Link(PyObject *op)
		{
Expand All		@@ -2269,12 +2283,19 @@ _PyObject_GC_Link(PyObject *op)
		!gcstate->collecting &&
		!_PyErr_Occurred(tstate))
		{
		gcstate->collecting = 1;
		gc_collect_generations(tstate);
		gcstate->collecting = 0;
		_Py_ScheduleGC(tstate->interp);
		}
		}

		void
		_Py_RunGC(PyThreadState *tstate)
		{
		GCState *gcstate = &tstate->interp->gc;
		gcstate->collecting = 1;
		gc_collect_generations(tstate);
		gcstate->collecting = 0;
		}

		static PyObject *
		gc_alloc(size_t basicsize, size_t presize)
		{
Expand Down

13 changes: 13 additions & 0 deletions 13 Modules/signalmodule.c

Show comments

View file

Open in desktop

Original file line number	Diff line number	Diff line change
Expand Up		@@ -1798,6 +1798,19 @@ int
		PyErr_CheckSignals(void)
		{
		PyThreadState *tstate = _PyThreadState_GET();

		/* Opportunistically check if the GC is scheduled to run and run it
		if we have a request. This is done here because native code needs
		to call this API if is going to run for some time without executing
		Python code to ensure signals are handled. Checking for the GC here
		allows long running native code to clean cycles created using the C-API
		even if it doesn't run the evaluation loop */
		struct _ceval_state *interp_ceval_state = &tstate->interp->ceval;
		if (_Py_atomic_load_relaxed(&interp_ceval_state->gc_scheduled)) {
		_Py_atomic_store_relaxed(&interp_ceval_state->gc_scheduled, 0);
Comment thread brandtbucher marked this conversation as resolved. Resolved Uh oh! There was an error while loading. Please reload this page.
		_Py_RunGC(tstate);
		}

		if (!_Py_ThreadCanHandleSignals(tstate->interp)) {
		return 0;
		}
Expand Down

30 changes: 20 additions & 10 deletions 30 Python/ceval_gil.c

Show comments

View file

Open in desktop

Original file line number	Diff line number	Diff line change
Expand Up		@@ -5,6 +5,7 @@
		#include "pycore_pyerrors.h" // _PyErr_Fetch()
		#include "pycore_pylifecycle.h" // _PyErr_Print()
		#include "pycore_initconfig.h" // _PyStatus_OK()
		#include "pycore_interp.h" // _Py_RunGC()
		#include "pycore_pymem.h" // _PyMem_IsPtrFreed()

		/*
Expand Down Expand Up		@@ -69,7 +70,8 @@ COMPUTE_EVAL_BREAKER(PyInterpreterState *interp,
		&& _Py_ThreadCanHandleSignals(interp))
		\| (_Py_atomic_load_relaxed_int32(&ceval2->pending.calls_to_do)
		&& _Py_ThreadCanHandlePendingCalls())
		\| ceval2->pending.async_exc);
		\| ceval2->pending.async_exc
		\| _Py_atomic_load_relaxed_int32(&ceval2->gc_scheduled));
		}


Expand Down Expand Up		@@ -938,6 +940,7 @@ _Py_HandlePending(PyThreadState *tstate)
		{
		_PyRuntimeState * const runtime = &_PyRuntime;
		struct _ceval_runtime_state *ceval = &runtime->ceval;
		struct _ceval_state *interp_ceval_state = &tstate->interp->ceval;

		/* Pending signals */
		if (_Py_atomic_load_relaxed_int32(&ceval->signals_pending)) {
Expand All		@@ -947,20 +950,26 @@ _Py_HandlePending(PyThreadState *tstate)
		}

		/* Pending calls */
		struct _ceval_state *ceval2 = &tstate->interp->ceval;
		if (_Py_atomic_load_relaxed_int32(&ceval2->pending.calls_to_do)) {
		if (_Py_atomic_load_relaxed_int32(&interp_ceval_state->pending.calls_to_do)) {
		if (make_pending_calls(tstate->interp) != 0) {
		return -1;
		}
		}

		/* GC scheduled to run */
		if (_Py_atomic_load_relaxed_int32(&interp_ceval_state->gc_scheduled)) {
		_Py_atomic_store_relaxed(&interp_ceval_state->gc_scheduled, 0);
		COMPUTE_EVAL_BREAKER(tstate->interp, ceval, interp_ceval_state);
		_Py_RunGC(tstate);
		}

		/* GIL drop request */
		if (_Py_atomic_load_relaxed_int32(&ceval2->gil_drop_request)) {
		if (_Py_atomic_load_relaxed_int32(&interp_ceval_state->gil_drop_request)) {
		/* Give another thread a chance */
		if (_PyThreadState_Swap(&runtime->gilstate, NULL) != tstate) {
		Py_FatalError("tstate mix-up");
		}
		drop_gil(ceval, ceval2, tstate);
		drop_gil(ceval, interp_ceval_state, tstate);

		/* Other threads may run now */

Expand All		@@ -981,16 +990,17 @@ _Py_HandlePending(PyThreadState *tstate)
		return -1;
		}

		#ifdef MS_WINDOWS
		// bpo-42296: On Windows, _PyEval_SignalReceived() can be called in a
		// different thread than the Python thread, in which case

		// It is possible that some of the conditions that trigger the eval breaker
		// are called in a different thread than the Python thread. An example of
		// this is bpo-42296: On Windows, _PyEval_SignalReceived() can be called in
		// a different thread than the Python thread, in which case
		// _Py_ThreadCanHandleSignals() is wrong. Recompute eval_breaker in the
		// current Python thread with the correct _Py_ThreadCanHandleSignals()
		// value. It prevents to interrupt the eval loop at every instruction if
		// the current Python thread cannot handle signals (if
		// _Py_ThreadCanHandleSignals() is false).
		COMPUTE_EVAL_BREAKER(tstate->interp, ceval, ceval2);
		#endif
		COMPUTE_EVAL_BREAKER(tstate->interp, ceval, interp_ceval_state);

		return 0;
		}
Expand Down

Add this suggestion to a batch that can be applied as a single commit. This suggestion is invalid because no changes were made to the code. Suggestions cannot be applied while the pull request is closed. Suggestions cannot be applied while viewing a subset of changes. Only one suggestion per line can be applied in a batch. Add this suggestion to a batch that can be applied as a single commit. Applying suggestions on deleted lines is not supported. You must change the existing code in this line in order to create a valid suggestion. Outdated suggestions cannot be applied. This suggestion has been applied or marked resolved. Suggestions cannot be applied from pending reviews. Suggestions cannot be applied on multi-line comments. Suggestions cannot be applied while the pull request is queued to merge. Suggestion cannot be applied right now. Please check back later.

You are visitor 01402503 — GeezerVison does not store the pages you look up.
Best viewed with Netscape Navigator 4.7 or Internet Explorer 6 at 800×600. No cookies required.