3 files changed, 38 insertions, 17 deletions
diff --git a/Include/internal/pycore_ceval.h b/Include/internal/pycore_ceval.h
index 23d0fa3..48fee69 100644
--- a/Include/internal/pycore_ceval.h
+++ b/Include/internal/pycore_ceval.h
@@ -193,6 +193,39 @@ int _PyEval_UnpackIterable(PyThreadState *tstate, PyObject *v, int argcnt, int a
 void _PyEval_FrameClearAndPop(PyThreadState *tstate, _PyInterpreterFrame *frame);
 
 
+#define _PY_GIL_DROP_REQUEST_BIT 0
+#define _PY_SIGNALS_PENDING_BIT 1
+#define _PY_CALLS_TO_DO_BIT 2
+#define _PY_ASYNC_EXCEPTION_BIT 3
+#define _PY_GC_SCHEDULED_BIT 4
+
+/* Reserve a few bits for future use */
+#define _PY_EVAL_EVENTS_BITS 8
+#define _PY_EVAL_EVENTS_MASK ((1 << _PY_EVAL_EVENTS_BITS)-1)
+
+static inline void
+_Py_set_eval_breaker_bit(PyInterpreterState *interp, uint32_t bit, uint32_t set)
+{
+    assert(set == 0 || set == 1);
+    uintptr_t to_set = set << bit;
+    uintptr_t mask = ((uintptr_t)1) << bit;
+    uintptr_t old = _Py_atomic_load_uintptr(&interp->ceval.eval_breaker);
+    if ((old & mask) == to_set) {
+        return;
+    }
+    uintptr_t new;
+    do {
+        new = (old & ~mask) | to_set;
+    } while (!_Py_atomic_compare_exchange_uintptr(&interp->ceval.eval_breaker, &old, new));
+}
+
+static inline bool
+_Py_eval_breaker_bit_is_set(PyInterpreterState *interp, int32_t bit)
+{
+    return _Py_atomic_load_uintptr_relaxed(&interp->ceval.eval_breaker) & (((uintptr_t)1) << bit);
+}
+
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/Include/internal/pycore_ceval_state.h b/Include/internal/pycore_ceval_state.h
index d0af5b5..47971fb 100644
--- a/Include/internal/pycore_ceval_state.h
+++ b/Include/internal/pycore_ceval_state.h
@@ -17,11 +17,7 @@ struct _pending_calls {
     int busy;
     PyThread_type_lock lock;
     /* Request for running pending calls. */
-    _Py_atomic_int calls_to_do;
-    /* Request for looking at the `async_exc` field of the current
-       thread state.
-       Guarded by the GIL. */
-    int async_exc;
+    int32_t calls_to_do;
 #define NPENDINGCALLS 32
     struct _pending_call {
         _Py_pending_call_func func;
@@ -62,11 +58,6 @@ struct _ceval_runtime_state {
         int _not_used;
 #endif
     } perf;
-    /* Request for checking signals. It is shared by all interpreters (see
-       bpo-40513). Any thread of any interpreter can receive a signal, but only
-       the main thread of the main interpreter can handle signals: see
-       _Py_ThreadCanHandleSignals(). */
-    _Py_atomic_int signals_pending;
     /* Pending calls to be made only on the main thread. */
     struct _pending_calls pending_mainthread;
 };
@@ -87,14 +78,12 @@ struct _ceval_state {
      * the fast path in the eval loop.
      * It is by far the hottest field in this struct and
      * should be placed at the beginning. */
-    _Py_atomic_int eval_breaker;
-    /* Request for dropping the GIL */
-    _Py_atomic_int gil_drop_request;
+    uintptr_t eval_breaker;
+    /* Avoid false sharing */
+    int64_t padding[7];
     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;
 };
 
diff --git a/Include/internal/pycore_interp.h b/Include/internal/pycore_interp.h
index ebf0228..21d1ee3 100644
--- a/Include/internal/pycore_interp.h
+++ b/Include/internal/pycore_interp.h
@@ -67,8 +67,7 @@ struct _is {
     int _initialized;
     int finalizing;
 
-    uint64_t monitoring_version;
-    uint64_t last_restart_version;
+    uintptr_t last_restart_version;
     struct pythreads {
         uint64_t next_unique_id;
         /* The linked list of threads, newest first. */