pythonGH-104580: Don't cache eval breaker in interpreter (pythonGH-104581)

Move eval-breaker to the front of the interpreter state.

Author: markshannon

Include/internal/pycore_ceval_state.h

@@ -81,14 +81,14 @@ struct _pending_calls {
 };
 
 struct _ceval_state {
-    int recursion_limit;
-    struct _gil_runtime_state *gil;
-    int own_gil;
     /* This single variable consolidates all requests to break out of
        the fast path in the eval loop. */
     _Py_atomic_int eval_breaker;
     /* Request for dropping the GIL */
     _Py_atomic_int gil_drop_request;
+    int recursion_limit;
+    struct _gil_runtime_state *gil;
+    int own_gil;
     /* The GC is ready to be executed */
     _Py_atomic_int gc_scheduled;
     struct _pending_calls pending;

Include/internal/pycore_interp.h

@@ -48,6 +48,7 @@ struct _Py_long_state {
    */
 struct _is {
 
+    struct _ceval_state ceval;
     PyInterpreterState *next;
 
     uint64_t monitoring_version;
@@ -92,7 +93,6 @@ struct _is {
 
     struct _obmalloc_state obmalloc;
 
-    struct _ceval_state ceval;
     struct _gc_runtime_state gc;
 
     struct _import_state imports;

Python/bytecodes.c

@@ -70,7 +70,6 @@ dummy_func(
     _PyInterpreterFrame *frame,
     unsigned char opcode,
     unsigned int oparg,
-    _Py_atomic_int * const eval_breaker,
     _PyCFrame cframe,
     _Py_CODEUNIT *next_instr,
     PyObject **stack_pointer,
@@ -143,7 +142,7 @@ dummy_func(
                 ERROR_IF(err, error);
                 next_instr--;
             }
-            else if (_Py_atomic_load_relaxed_int32(eval_breaker) && oparg < 2) {
+            else if (_Py_atomic_load_relaxed_int32(&tstate->interp->ceval.eval_breaker) && oparg < 2) {
                 goto handle_eval_breaker;
             }
         }
@@ -170,7 +169,7 @@ dummy_func(
                     next_instr = frame->prev_instr;
                     DISPATCH();
                 }
-                if (_Py_atomic_load_relaxed_int32(eval_breaker) && oparg < 2) {
+                if (_Py_atomic_load_relaxed_int32(&tstate->interp->ceval.eval_breaker) && oparg < 2) {
                     goto handle_eval_breaker;
                 }
             }

Python/ceval.c

@@ -652,7 +652,6 @@ _PyEval_EvalFrameDefault(PyThreadState *tstate, _PyInterpreterFrame *frame, int
     // for the big switch below (in combination with the EXTRA_CASES macro).
     uint8_t opcode;        /* Current opcode */
     int oparg;         /* Current opcode argument, if any */
-    _Py_atomic_int * const eval_breaker = &tstate->interp->ceval.eval_breaker;
 #ifdef LLTRACE
     int lltrace = 0;
 #endif

Python/ceval_macros.h

@@ -116,7 +116,7 @@
 
 #define CHECK_EVAL_BREAKER() \
     _Py_CHECK_EMSCRIPTEN_SIGNALS_PERIODICALLY(); \
-    if (_Py_atomic_load_relaxed_int32(eval_breaker)) { \
+    if (_Py_atomic_load_relaxed_int32(&tstate->interp->ceval.eval_breaker)) { \
         goto handle_eval_breaker; \
     }