Allow for resizing the stack area.

Author: tannewt

main.c

@@ -52,6 +52,7 @@
 #include "supervisor/messages/en-US.h"
 #include "supervisor/shared/autoreload.h"
 #include "supervisor/shared/rgb_led_status.h"
+#include "supervisor/shared/stack.h"
 #include "supervisor/serial.h"
 
 void do_str(const char *src, mp_parse_input_kind_t input_kind) {
@@ -81,11 +82,11 @@ void start_mp(supervisor_allocation* heap) {
     // Stack limit should be less than real stack size, so we have a chance
     // to recover from limit hit.  (Limit is measured in bytes.)
     mp_stack_ctrl_init();
-    mp_stack_set_limit((char*)&_estack - (char*)&_ebss - 1024);
+    mp_stack_set_limit(stack_alloc->length - 1024);
 
 #if MICROPY_MAX_STACK_USAGE
     // _ezero (same as _ebss) is an int, so start 4 bytes above it.
-    mp_stack_set_bottom(&_ezero + 1);
+    mp_stack_set_bottom(stack_alloc->ptr);
     mp_stack_fill_with_sentinel();
 #endif
 
@@ -97,7 +98,7 @@ void start_mp(supervisor_allocation* heap) {
     readline_init0();
 
     #if MICROPY_ENABLE_GC
-    gc_init(heap->ptr, heap->ptr + heap->length);
+    gc_init(heap->ptr, heap->ptr + heap->length / 4);
     #endif
     mp_init();
     mp_obj_list_init(mp_sys_path, 0);
@@ -171,6 +172,8 @@ bool run_code_py(safe_mode_t safe_mode) {
         const char *double_extension_filenames[] = STRING_LIST("code.txt.py", "code.py.txt", "code.txt.txt","code.py.py",
                                                     "main.txt.py", "main.py.txt", "main.txt.txt","main.py.py");
 
+        stack_resize();
+        filesystem_flush();
         supervisor_allocation* heap = allocate_remaining_memory();
         start_mp(heap);
         found_main = maybe_run_list(supported_filenames, &result);
@@ -310,6 +313,12 @@ void __attribute__ ((noinline)) run_boot_py(safe_mode_t safe_mode) {
         }
         #endif
 
+        stack_init();
+        // TODO(tannewt): Allocate temporary space to hold custom usb descriptors.
+        filesystem_flush();
+        supervisor_allocation* heap = allocate_remaining_memory();
+        start_mp(heap);
+
         // TODO(tannewt): Re-add support for flashing boot error output.
         bool found_boot = maybe_run_list(boot_py_filenames, NULL);
         (void) found_boot;
@@ -325,11 +334,16 @@ void __attribute__ ((noinline)) run_boot_py(safe_mode_t safe_mode) {
         // Reset to remove any state that boot.py setup. It should only be used to
         // change internal state that's not in the heap.
         reset_port();
+        reset_board();
+        stop_mp();
+        free_memory(heap);
     }
 }
 
 int run_repl(void) {
     int exit_code = PYEXEC_FORCED_EXIT;
+    stack_resize();
+    filesystem_flush();
     supervisor_allocation* heap = allocate_remaining_memory();
     start_mp(heap);
     autoreload_suspend();
@@ -349,7 +363,7 @@ int run_repl(void) {
 
 int __attribute__((used)) main(void) {
     memory_init();
-    
+
     // initialise the cpu and peripherals
     safe_mode_t safe_mode = port_init();
 

ports/atmel-samd/mpconfigport.h

@@ -338,4 +338,8 @@ void run_background_tasks(void);
 #define CIRCUITPY_AUTORELOAD_DELAY_MS 500
 #define CIRCUITPY_BOOT_OUTPUT_FILE "/boot_out.txt"
 
+// TODO(tannewt): Make this 6k+ for any non-express M4 boards because they cache sectors on the
+// stack.
+#define CIRCUITPY_DEFAULT_STACK_SIZE 2048
+
 #endif  // __INCLUDED_MPCONFIGPORT_H

ports/atmel-samd/supervisor/filesystem.c

@@ -51,7 +51,6 @@ void filesystem_init(bool create_allowed, bool force_create) {
 
     // try to mount the flash
     FRESULT res = f_mount(&vfs_fat->fatfs);
-    force_create = true;
 
     if ((res == FR_NO_FILESYSTEM && create_allowed) || force_create) {
         // No filesystem so create a fresh one, or reformat has been requested.

ports/atmel-samd/supervisor/memory.c

@@ -40,9 +40,6 @@ extern uint32_t _estack;
 void memory_init(void) {
     low_address = &_ebss;
     high_address = &_estack;
-
-    // snag 3k for stack
-    allocate_memory(1024*4, true);
 }
 
 void free_memory(supervisor_allocation* allocation) {
@@ -56,8 +53,23 @@ void free_memory(supervisor_allocation* allocation) {
     }
     if (allocation->ptr == high_address) {
         high_address += allocation->length / 4;
+        for (index++; index < CIRCUITPY_SUPERVISOR_ALLOC_COUNT; index++) {
+            if (allocations[index].ptr != NULL) {
+                break;
+            }
+            high_address += allocations[index].length / 4;
+        }
     } else if (allocation->ptr + allocation->length / 4 == low_address) {
         low_address = allocation->ptr;
+        for (index--; index >= 0; index--) {
+            if (allocations[index].ptr != NULL) {
+                break;
+            }
+            low_address -= allocations[index].length / 4;
+        }
+    } else {
+        // Freed memory isn't in the middle so skip updating bounds. The memory will be added to the
+        // middle when the memory to the inside is freed.
     }
     allocation->ptr = NULL;
 }

ports/nrf/mpconfigport.h

@@ -233,5 +233,6 @@ void run_background_tasks(void);
 #define MICROPY_VM_HOOK_RETURN  run_background_tasks();
 
 //#define CIRCUITPY_BOOT_OUTPUT_FILE "/boot_out.txt"
+#define CIRCUITPY_DEFAULT_STACK_SIZE 2048
 
 #endif

ports/nrf/supervisor/memory.c

@@ -0,0 +1,112 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2018 Scott Shawcroft for Adafruit Industries
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "supervisor/memory.h"
+
+#include <stddef.h>
+
+#define CIRCUITPY_SUPERVISOR_ALLOC_COUNT 8
+
+static supervisor_allocation allocations[CIRCUITPY_SUPERVISOR_ALLOC_COUNT];
+// We use uint32_t* to ensure word (4 byte) alignment.
+uint32_t* low_address;
+uint32_t* high_address;
+extern uint32_t _ebss;
+extern uint32_t _estack;
+
+void memory_init(void) {
+    low_address = &_ebss;
+    high_address = &_estack;
+}
+
+void free_memory(supervisor_allocation* allocation) {
+    uint8_t index = 0;
+    bool found = false;
+    for (index = 0; index < CIRCUITPY_SUPERVISOR_ALLOC_COUNT; index++) {
+        found = allocation == &allocations[index];
+        if (found) {
+            break;
+        }
+    }
+    if (allocation->ptr == high_address) {
+        high_address += allocation->length / 4;
+        for (index++; index < CIRCUITPY_SUPERVISOR_ALLOC_COUNT; index++) {
+            if (allocations[index].ptr != NULL) {
+                break;
+            }
+            high_address += allocations[index].length / 4;
+        }
+    } else if (allocation->ptr + allocation->length / 4 == low_address) {
+        low_address = allocation->ptr;
+        for (index--; index >= 0; index--) {
+            if (allocations[index].ptr != NULL) {
+                break;
+            }
+            low_address -= allocations[index].length / 4;
+        }
+    } else {
+        // Freed memory isn't in the middle so skip updating bounds. The memory will be added to the
+        // middle when the memory to the inside is freed.
+    }
+    allocation->ptr = NULL;
+}
+
+supervisor_allocation* allocate_remaining_memory(void) {
+    if (low_address == high_address) {
+        return NULL;
+    }
+    return allocate_memory((high_address - low_address) * 4, false);
+}
+
+supervisor_allocation* allocate_memory(uint32_t length, bool high) {
+    if ((high_address - low_address) * 4 < (int32_t) length) {
+        return NULL;
+    }
+    uint8_t index = 0;
+    int8_t direction = 1;
+    if (high) {
+        index = CIRCUITPY_SUPERVISOR_ALLOC_COUNT - 1;
+        direction = -1;
+    }
+    for (; index < CIRCUITPY_SUPERVISOR_ALLOC_COUNT; index += direction) {
+        if (allocations[index].ptr == NULL) {
+            break;
+        }
+    }
+    if (index >= CIRCUITPY_SUPERVISOR_ALLOC_COUNT) {
+        return NULL;
+    }
+    supervisor_allocation* alloc = &allocations[index];
+    if (high) {
+        high_address -= length / 4;
+        alloc->ptr = high_address;
+    } else {
+        alloc->ptr = low_address;
+        low_address += length / 4;
+    }
+    alloc->length = length;
+    return alloc;
+}

shared-bindings/supervisor/__init__.c

@@ -23,17 +23,17 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
- #include "py/obj.h"
- #include "py/runtime.h"
- #include "py/reload.h"
+#include "py/obj.h"
+#include "py/runtime.h"
+#include "py/reload.h"
 
- #include "lib/utils/interrupt_char.h"
- #include "supervisor/shared/autoreload.h"
+#include "lib/utils/interrupt_char.h"
+#include "supervisor/shared/autoreload.h"
+#include "supervisor/shared/rgb_led_status.h"
+#include "supervisor/shared/stack.h"
 
- #include "supervisor/shared/rgb_led_status.h"
-
- #include "shared-bindings/supervisor/__init__.h"
- #include "shared-bindings/supervisor/Runtime.h"
+#include "shared-bindings/supervisor/__init__.h"
+#include "shared-bindings/supervisor/Runtime.h"
 
 //| :mod:`supervisor` --- Supervisor settings
 //| =================================================
@@ -107,15 +107,21 @@ STATIC mp_obj_t supervisor_reload(void) {
 }
 MP_DEFINE_CONST_FUN_OBJ_0(supervisor_reload_obj, supervisor_reload);
 
-//| .. method:: set_main_file(filename)
+//| .. method:: set_next_stack_limit(size)
 //|
-//|   Set which file to run after a reload.
+//|   Set the size of the stack for the next vm run. If its too large, the default will be used.
 //|
-STATIC mp_obj_t supervisor_set_main_file(void) {
-    
+STATIC mp_obj_t supervisor_set_next_stack_limit(mp_obj_t size_obj) {
+    mp_int_t size = mp_obj_get_int(size_obj);
+
+    if (size < 256) {
+        mp_raise_ValueError("Stack size must be at least 256");
+    }
+    set_next_stack_size(size);
+
     return mp_const_none;
 }
-MP_DEFINE_CONST_FUN_OBJ_0(supervisor_set_main_file_obj, supervisor_set_main_file);
+MP_DEFINE_CONST_FUN_OBJ_1(supervisor_set_next_stack_limit_obj, supervisor_set_next_stack_limit);
 
 STATIC const mp_rom_map_elem_t supervisor_module_globals_table[] = {
     { MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_supervisor) },
@@ -124,7 +130,7 @@ STATIC const mp_rom_map_elem_t supervisor_module_globals_table[] = {
     { MP_OBJ_NEW_QSTR(MP_QSTR_set_rgb_status_brightness),  MP_ROM_PTR(&supervisor_set_rgb_status_brightness_obj) },
     { MP_ROM_QSTR(MP_QSTR_runtime),  MP_ROM_PTR(&common_hal_supervisor_runtime_obj) },
     { MP_ROM_QSTR(MP_QSTR_reload),  MP_ROM_PTR(&supervisor_reload_obj) },
-    { MP_ROM_QSTR(MP_QSTR_set_main_file),  MP_ROM_PTR(&supervisor_set_main_file_obj) },
+    { MP_ROM_QSTR(MP_QSTR_set_next_stack_limit),  MP_ROM_PTR(&supervisor_set_next_stack_limit_obj) },
 
 };
 

supervisor/shared/stack.c

@@ -0,0 +1,74 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2018 Scott Shawcroft for Adafruit Industries
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "stack.h"
+
+#include "py/mpconfig.h"
+#include "supervisor/cpu.h"
+
+extern uint32_t _estack;
+
+static uint32_t next_stack_size = CIRCUITPY_DEFAULT_STACK_SIZE;
+static uint32_t current_stack_size = 0;
+supervisor_allocation* stack_alloc = NULL;
+
+#define EXCEPTION_STACK_SIZE 1024
+
+void allocate_stack(void) {
+    mp_uint_t regs[10];
+    mp_uint_t sp = cpu_get_regs_and_sp(regs);
+
+    mp_uint_t c_size = (uint32_t) &_estack - sp;
+
+    stack_alloc = allocate_memory(c_size + next_stack_size + EXCEPTION_STACK_SIZE, true);
+    if (stack_alloc == NULL) {
+        stack_alloc = allocate_memory(c_size + CIRCUITPY_DEFAULT_STACK_SIZE + EXCEPTION_STACK_SIZE, true);
+        current_stack_size = CIRCUITPY_DEFAULT_STACK_SIZE;
+    } else {
+        current_stack_size = next_stack_size;
+    }
+}
+
+inline void stack_init(void) {
+    allocate_stack();
+}
+
+inline void stack_resize(void) {
+    if (next_stack_size == current_stack_size) {
+        return;
+    }
+    free_memory(stack_alloc);
+    stack_alloc = NULL;
+    allocate_stack();
+}
+
+void set_next_stack_size(uint32_t size) {
+    next_stack_size = size;
+}
+
+uint32_t get_current_stack_size(void) {
+    return current_stack_size;
+}