py/mpstate: Make exceptions thread-local.

This moves mp_pending_exception from mp_state_vm_t to mp_state_thread_t.
This allows exceptions to be scheduled on a specific thread.

Signed-off-by: David Lechner <[email protected]>

Author: dlech

ports/esp8266/modnetwork.c

@@ -237,7 +237,7 @@ STATIC mp_obj_t esp_scan(mp_obj_t self_in) {
     while (esp_scan_list != NULL) {
         // our esp_scan_cb is called via ets_loop_iter so it's safe to set the
         // esp_scan_list variable to NULL without disabling interrupts
-        if (MP_STATE_VM(mp_pending_exception) != NULL) {
+        if (MP_STATE_THREAD(mp_pending_exception) != NULL) {
             esp_scan_list = NULL;
             mp_handle_pending(true);
         }

ports/nrf/boards/microbit/modules/microbitdisplay.c

@@ -149,7 +149,7 @@ STATIC void async_stop(void) {
 STATIC void wait_for_event(void) {
     while (!wakeup_event) {
         // allow CTRL-C to stop the animation
-        if (MP_STATE_VM(mp_pending_exception) != MP_OBJ_NULL) {
+        if (MP_STATE_THREAD(mp_pending_exception) != MP_OBJ_NULL) {
             async_stop();
             return;
         }

ports/nrf/modules/music/modmusic.c

@@ -140,7 +140,7 @@ STATIC void wait_async_music_idle(void) {
     // wait for the async music state to become idle
     while (music_data->async_state != ASYNC_MUSIC_STATE_IDLE) {
         // allow CTRL-C to stop the music
-        if (MP_STATE_VM(mp_pending_exception) != MP_OBJ_NULL) {
+        if (MP_STATE_THREAD(mp_pending_exception) != MP_OBJ_NULL) {
             music_data->async_state = ASYNC_MUSIC_STATE_IDLE;
             pwm_set_duty_cycle(music_data->async_pin->pin, 0); // TODO: remove pin setting.
             break;

ports/pic16bit/board.c

@@ -140,7 +140,7 @@ int switch_get(int sw) {
 // TODO need an irq
 void uart_rx_irq(void) {
     if (c == interrupt_char) {
-        MP_STATE_VM(mp_pending_exception) = MP_STATE_PORT(keyboard_interrupt_obj);
+        MP_STATE_THREAD(mp_pending_exception) = MP_STATE_PORT(keyboard_interrupt_obj);
     }
 }
 */

ports/stm32/pendsv.c

@@ -60,10 +60,10 @@ void pendsv_init(void) {
 // the given exception object using nlr_jump in the context of the top-level
 // thread.
 void pendsv_kbd_intr(void) {
-    if (MP_STATE_VM(mp_pending_exception) == MP_OBJ_NULL) {
+    if (MP_STATE_THREAD(mp_pending_exception) == MP_OBJ_NULL) {
         mp_sched_keyboard_interrupt();
     } else {
-        MP_STATE_VM(mp_pending_exception) = MP_OBJ_NULL;
+        MP_STATE_THREAD(mp_pending_exception) = MP_OBJ_NULL;
         pendsv_object = &MP_STATE_VM(mp_kbd_exception);
         SCB->ICSR = SCB_ICSR_PENDSVSET_Msk;
     }

ports/unix/unix_mphal.c

@@ -54,7 +54,7 @@ STATIC void sighandler(int signum) {
         sigprocmask(SIG_SETMASK, &mask, NULL);
         nlr_raise(MP_OBJ_FROM_PTR(&MP_STATE_VM(mp_kbd_exception)));
         #else
-        if (MP_STATE_VM(mp_pending_exception) == MP_OBJ_FROM_PTR(&MP_STATE_VM(mp_kbd_exception))) {
+        if (MP_STATE_THREAD(mp_pending_exception) == MP_OBJ_FROM_PTR(&MP_STATE_VM(mp_kbd_exception))) {
             // this is the second time we are called, so die straight away
             exit(1);
         }

ports/windows/windows_mphal.c

@@ -80,7 +80,7 @@ void mp_hal_stdio_mode_orig(void) {
 // the thread created for handling it might not be running yet so we'd miss the notification.
 BOOL WINAPI console_sighandler(DWORD evt) {
     if (evt == CTRL_C_EVENT) {
-        if (MP_STATE_VM(mp_pending_exception) == MP_OBJ_FROM_PTR(&MP_STATE_VM(mp_kbd_exception))) {
+        if (MP_STATE_THREAD(mp_pending_exception) == MP_OBJ_FROM_PTR(&MP_STATE_VM(mp_kbd_exception))) {
             // this is the second time we are called, so die straight away
             exit(1);
         }

py/modthread.c

@@ -174,6 +174,8 @@ STATIC void *thread_entry(void *args_in) {
     // The GC starts off unlocked on this thread.
     ts.gc_lock_depth = 0;
 
+    ts.mp_pending_exception = MP_OBJ_NULL;
+
     // set locals and globals from the calling context
     mp_locals_set(args->dict_locals);
     mp_globals_set(args->dict_globals);
@@ -184,7 +186,6 @@ STATIC void *thread_entry(void *args_in) {
     mp_thread_start();
 
     // TODO set more thread-specific state here:
-    //  mp_pending_exception? (root pointer)
     //  cur_exception (root pointer)
 
     DEBUG_printf("[thread] start ts=%p args=%p stack=%p\n", &ts, &args, MP_STATE_THREAD(stack_top));

py/mpstate.h

@@ -137,9 +137,6 @@ typedef struct _mp_state_vm_t {
     // dictionary with loaded modules (may be exposed as sys.modules)
     mp_obj_dict_t mp_loaded_modules_dict;
 
-    // pending exception object (MP_OBJ_NULL if not pending)
-    volatile mp_obj_t mp_pending_exception;
-
     #if MICROPY_ENABLE_SCHEDULER
     mp_sched_item_t sched_queue[MICROPY_SCHEDULER_DEPTH];
     #endif
@@ -266,6 +263,9 @@ typedef struct _mp_state_thread_t {
 
     nlr_buf_t *nlr_top;
 
+    // pending exception object (MP_OBJ_NULL if not pending)
+    volatile mp_obj_t mp_pending_exception;
+
     #if MICROPY_PY_SYS_SETTRACE
     mp_obj_t prof_trace_callback;
     bool prof_callback_is_executing;

py/profile.c

@@ -297,7 +297,7 @@ STATIC mp_obj_t mp_prof_callback_invoke(mp_obj_t callback, prof_callback_args_t
 
     mp_prof_is_executing = false;
 
-    if (MP_STATE_VM(mp_pending_exception) != MP_OBJ_NULL) {
+    if (MP_STATE_THREAD(mp_pending_exception) != MP_OBJ_NULL) {
         mp_handle_pending(true);
     }
     return top;