bpo-39984: Add PyInterpreterState.ceval (GH-19047)

subinterpreters: Move _PyRuntimeState.ceval.tracing_possible to
PyInterpreterState.ceval.tracing_possible: each interpreter now has
its own variable.

Changes:

* Add _ceval_state structure.
* Add PyInterpreterState.ceval field.
* _PyEval_EvalFrameDefault(): add ceval2 variable (struct _ceval_state*).
* Rename _PyEval_Initialize() to _PyEval_InitRuntimeState().
* Add _PyEval_InitState().
* Don't export internal _Py_FinishPendingCalls() and
  _PyEval_FiniThreads() functions anymore.

2 files changed, 14 insertions, 9 deletions

diff --git a/Include/internal/pycore_ceval.h b/Include/internal/pycore_ceval.h
index ae6ef9a..ec00d18 100644
--- a/Include/internal/pycore_ceval.h
+++ b/Include/internal/pycore_ceval.h
@@ -15,9 +15,10 @@ struct _frame;
 
 #include "pycore_pystate.h"   /* PyInterpreterState.eval_frame */
 
-PyAPI_FUNC(void) _Py_FinishPendingCalls(PyThreadState *tstate);
-PyAPI_FUNC(void) _PyEval_Initialize(struct _ceval_runtime_state *);
-PyAPI_FUNC(void) _PyEval_FiniThreads(
+extern void _Py_FinishPendingCalls(PyThreadState *tstate);
+extern void _PyEval_InitRuntimeState(struct _ceval_runtime_state *);
+extern void _PyEval_InitState(struct _ceval_state *);
+extern void _PyEval_FiniThreads(
     struct _ceval_runtime_state *ceval);
 PyAPI_FUNC(void) _PyEval_SignalReceived(
     struct _ceval_runtime_state *ceval);
diff --git a/Include/internal/pycore_pystate.h b/Include/internal/pycore_pystate.h
index 0a83546..0e3a9e6 100644
--- a/Include/internal/pycore_pystate.h
+++ b/Include/internal/pycore_pystate.h
@@ -35,12 +35,6 @@ struct _pending_calls {
 
 struct _ceval_runtime_state {
     int recursion_limit;
-    /* Records whether tracing is on for any thread.  Counts the number
-       of threads for which tstate->c_tracefunc is non-NULL, so if the
-       value is 0, we know we don't have to check this thread's
-       c_tracefunc.  This speeds up the if statement in
-       PyEval_EvalFrameEx() after fast_next_opcode. */
-    int tracing_possible;
     /* This single variable consolidates all requests to break out of
        the fast path in the eval loop. */
     _Py_atomic_int eval_breaker;
@@ -52,6 +46,15 @@ struct _ceval_runtime_state {
     struct _gil_runtime_state gil;
 };
 
+struct _ceval_state {
+    /* Records whether tracing is on for any thread.  Counts the number
+       of threads for which tstate->c_tracefunc is non-NULL, so if the
+       value is 0, we know we don't have to check this thread's
+       c_tracefunc.  This speeds up the if statement in
+       _PyEval_EvalFrameDefault() after fast_next_opcode. */
+    int tracing_possible;
+};
+
 /* interpreter state */
 
 #define _PY_NSMALLPOSINTS           257
@@ -75,6 +78,7 @@ struct _is {
 
     int finalizing;
 
+    struct _ceval_state ceval;
     struct _gc_runtime_state gc;
 
     PyObject *modules;