[Python-checkins] bpo-40521: Make slice cache per-interpreter (GH-20637)
Victor Stinner
webhook-mailer at python.org
Thu Jun 4 19:14:48 EDT 2020
https://github.com/python/cpython/commit/7daba6f221e713f7f60c613b246459b07d179f91
commit: 7daba6f221e713f7f60c613b246459b07d179f91
branch: master
author: Victor Stinner <vstinner at python.org>
committer: GitHub <noreply at github.com>
date: 2020-06-05T01:14:40+02:00
summary:
bpo-40521: Make slice cache per-interpreter (GH-20637)
Each interpreter now has its own slice cache:
* Move slice cache into PyInterpreterState.
* Add tstate parameter to _PySlice_Fini().
files:
M Include/internal/pycore_interp.h
M Include/internal/pycore_pylifecycle.h
M Misc/NEWS.d/next/Core and Builtins/2020-05-20-01-17-34.bpo-40521.wvAehI.rst
M Objects/sliceobject.c
M Python/pylifecycle.c
diff --git a/Include/internal/pycore_interp.h b/Include/internal/pycore_interp.h
index c0eed00f36581..70054efe7ec71 100644
--- a/Include/internal/pycore_interp.h
+++ b/Include/internal/pycore_interp.h
@@ -187,6 +187,10 @@ struct _is {
#endif
struct _Py_tuple_state tuple;
struct _Py_float_state float_state;
+
+ /* Using a cache is very effective since typically only a single slice is
+ created and then deleted again. */
+ PySliceObject *slice_cache;
};
/* Used by _PyImport_Cleanup() */
diff --git a/Include/internal/pycore_pylifecycle.h b/Include/internal/pycore_pylifecycle.h
index 2643abca0f553..bba9bd9b2bdb2 100644
--- a/Include/internal/pycore_pylifecycle.h
+++ b/Include/internal/pycore_pylifecycle.h
@@ -65,7 +65,7 @@ extern void _PyList_Fini(void);
extern void _PySet_Fini(void);
extern void _PyBytes_Fini(void);
extern void _PyFloat_Fini(PyThreadState *tstate);
-extern void _PySlice_Fini(void);
+extern void _PySlice_Fini(PyThreadState *tstate);
extern void _PyAsyncGen_Fini(void);
extern void PyOS_FiniInterrupts(void);
diff --git a/Misc/NEWS.d/next/Core and Builtins/2020-05-20-01-17-34.bpo-40521.wvAehI.rst b/Misc/NEWS.d/next/Core and Builtins/2020-05-20-01-17-34.bpo-40521.wvAehI.rst
index 016f11668ee44..74c7a499bdef0 100644
--- a/Misc/NEWS.d/next/Core and Builtins/2020-05-20-01-17-34.bpo-40521.wvAehI.rst
+++ b/Misc/NEWS.d/next/Core and Builtins/2020-05-20-01-17-34.bpo-40521.wvAehI.rst
@@ -1,2 +1,3 @@
-Tuple free lists, empty tuple singleton, and float free list are no longer
-shared by all interpreters: each interpreter now its own free lists.
+The tuple free lists, the empty tuple singleton, the float free list, and the
+slice cache are no longer shared by all interpreters: each interpreter now has
+its own free lists and caches.
diff --git a/Objects/sliceobject.c b/Objects/sliceobject.c
index 391711f711aae..f97a570a787f0 100644
--- a/Objects/sliceobject.c
+++ b/Objects/sliceobject.c
@@ -15,7 +15,7 @@ this type and there is exactly one in existence.
#include "Python.h"
#include "pycore_abstract.h" // _PyIndex_Check()
-#include "pycore_object.h"
+#include "pycore_object.h" // _PyObject_GC_TRACK()
#include "structmember.h" // PyMemberDef
static PyObject *
@@ -95,16 +95,13 @@ PyObject _Py_EllipsisObject = {
/* Slice object implementation */
-/* Using a cache is very effective since typically only a single slice is
- * created and then deleted again
- */
-static PySliceObject *slice_cache = NULL;
-void _PySlice_Fini(void)
+void _PySlice_Fini(PyThreadState *tstate)
{
- PySliceObject *obj = slice_cache;
+ PyInterpreterState *interp = tstate->interp;
+ PySliceObject *obj = interp->slice_cache;
if (obj != NULL) {
- slice_cache = NULL;
+ interp->slice_cache = NULL;
PyObject_GC_Del(obj);
}
}
@@ -116,10 +113,11 @@ void _PySlice_Fini(void)
PyObject *
PySlice_New(PyObject *start, PyObject *stop, PyObject *step)
{
+ PyInterpreterState *interp = _PyInterpreterState_GET();
PySliceObject *obj;
- if (slice_cache != NULL) {
- obj = slice_cache;
- slice_cache = NULL;
+ if (interp->slice_cache != NULL) {
+ obj = interp->slice_cache;
+ interp->slice_cache = NULL;
_Py_NewReference((PyObject *)obj);
} else {
obj = PyObject_GC_New(PySliceObject, &PySlice_Type);
@@ -324,14 +322,17 @@ Create a slice object. This is used for extended slicing (e.g. a[0:10:2]).");
static void
slice_dealloc(PySliceObject *r)
{
+ PyInterpreterState *interp = _PyInterpreterState_GET();
_PyObject_GC_UNTRACK(r);
Py_DECREF(r->step);
Py_DECREF(r->start);
Py_DECREF(r->stop);
- if (slice_cache == NULL)
- slice_cache = r;
- else
+ if (interp->slice_cache == NULL) {
+ interp->slice_cache = r;
+ }
+ else {
PyObject_GC_Del(r);
+ }
}
static PyObject *
diff --git a/Python/pylifecycle.c b/Python/pylifecycle.c
index 716303cffc764..ee9d698d7d089 100644
--- a/Python/pylifecycle.c
+++ b/Python/pylifecycle.c
@@ -1265,9 +1265,9 @@ finalize_interp_types(PyThreadState *tstate, int is_main_interp)
if (is_main_interp) {
_PyDict_Fini();
- _PySlice_Fini();
}
+ _PySlice_Fini(tstate);
_PyWarnings_Fini(tstate->interp);
if (is_main_interp) {
More information about the Python-checkins
mailing list