1 /*
2  * This file is part of the MicroPython project, http://micropython.org/
3  *
4  * The MIT License (MIT)
5  *
6  * Copyright (c) 2014 Damien P. George
7  *
8  * Permission is hereby granted, free of charge, to any person obtaining a copy
9  * of this software and associated documentation files (the "Software"), to deal
10  * in the Software without restriction, including without limitation the rights
11  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
12  * copies of the Software, and to permit persons to whom the Software is
13  * furnished to do so, subject to the following conditions:
14  *
15  * The above copyright notice and this permission notice shall be included in
16  * all copies or substantial portions of the Software.
17  *
18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
21  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
22  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
23  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
24  * THE SOFTWARE.
25  */
26 #ifndef MICROPY_INCLUDED_PY_MPSTATE_H
27 #define MICROPY_INCLUDED_PY_MPSTATE_H
28 
29 #include <stdint.h>
30 
31 #include "py/mpconfig.h"
32 #include "py/mpthread.h"
33 #include "py/misc.h"
34 #include "py/nlr.h"
35 #include "py/obj.h"
36 #include "py/objlist.h"
37 #include "py/objexcept.h"
38 
39 // This file contains structures defining the state of the MicroPython
40 // memory system, runtime and virtual machine.  The state is a global
41 // variable, but in the future it is hoped that the state can become local.
42 
43 // This structure contains dynamic configuration for the compiler.
44 #if MICROPY_DYNAMIC_COMPILER
45 typedef struct mp_dynamic_compiler_t {
46     uint8_t small_int_bits; // must be <= host small_int_bits
47     bool opt_cache_map_lookup_in_bytecode;
48     bool py_builtins_str_unicode;
49     uint8_t native_arch;
50     uint8_t nlr_buf_num_regs;
51 } mp_dynamic_compiler_t;
52 extern mp_dynamic_compiler_t mp_dynamic_compiler;
53 #endif
54 
55 // These are the values for sched_state
56 #define MP_SCHED_IDLE (1)
57 #define MP_SCHED_LOCKED (-1)
58 #define MP_SCHED_PENDING (0) // 0 so it's a quick check in the VM
59 
60 typedef struct _mp_sched_item_t {
61     mp_obj_t func;
62     mp_obj_t arg;
63 } mp_sched_item_t;
64 
65 // This structure hold information about the memory allocation system.
66 typedef struct _mp_state_mem_t {
67     #if MICROPY_MEM_STATS
68     size_t total_bytes_allocated;
69     size_t current_bytes_allocated;
70     size_t peak_bytes_allocated;
71     #endif
72 
73     byte *gc_alloc_table_start;
74 
75     size_t gc_alloc_table_byte_len;
76     #if MICROPY_ENABLE_FINALISER
77     byte *gc_finaliser_table_start;
78     #endif
79     byte *gc_pool_start;
80     byte *gc_pool_end;
81 
82     int gc_stack_overflow;
83     MICROPY_GC_STACK_ENTRY_TYPE gc_stack[MICROPY_ALLOC_GC_STACK_SIZE];
84     uint16_t gc_lock_depth;
85 
86     // This variable controls auto garbage collection.  If set to 0 then the
87     // GC won't automatically run when gc_alloc can't find enough blocks.  But
88     // you can still allocate/free memory and also explicitly call gc_collect.
89     uint16_t gc_auto_collect_enabled;
90 
91     #if MICROPY_GC_ALLOC_THRESHOLD
92     size_t gc_alloc_amount;
93     size_t gc_alloc_threshold;
94     #endif
95 
96     size_t gc_last_free_atb_index;
97 
98     #if MICROPY_PY_GC_COLLECT_RETVAL
99     size_t gc_collected;
100     #endif
101 
102     #if MICROPY_PY_THREAD && !MICROPY_PY_THREAD_GIL
103     // This is a global mutex used to make the GC thread-safe.
104     mp_thread_mutex_t gc_mutex;
105     #endif
106 } mp_state_mem_t;
107 
108 // This structure hold runtime and VM information.  It includes a section
109 // which contains root pointers that must be scanned by the GC.
110 typedef struct _mp_state_vm_t {
111     //
112     // CONTINUE ROOT POINTER SECTION
113     // This must start at the start of this structure and follows
114     // the state in the mp_state_thread_t structure, continuing
115     // the root pointer section from there.
116     //
117 
118     qstr_pool_t *last_pool;
119 
120     // non-heap memory for creating an exception if we can't allocate RAM
121     mp_obj_exception_t mp_emergency_exception_obj;
122 
123     // memory for exception arguments if we can't allocate RAM
124     #if MICROPY_ENABLE_EMERGENCY_EXCEPTION_BUF
125     #if MICROPY_EMERGENCY_EXCEPTION_BUF_SIZE > 0
126     // statically allocated buf (needs to be aligned to mp_obj_t)
127     mp_obj_t mp_emergency_exception_buf[MICROPY_EMERGENCY_EXCEPTION_BUF_SIZE / sizeof(mp_obj_t)];
128     #else
129     // dynamically allocated buf
130     byte *mp_emergency_exception_buf;
131     #endif
132     #endif
133 
134     #if MICROPY_KBD_EXCEPTION
135     // exception object of type KeyboardInterrupt
136     mp_obj_exception_t mp_kbd_exception;
137     #endif
138 
139     // dictionary with loaded modules (may be exposed as sys.modules)
140     mp_obj_dict_t mp_loaded_modules_dict;
141 
142     #if MICROPY_ENABLE_SCHEDULER
143     mp_sched_item_t sched_queue[MICROPY_SCHEDULER_DEPTH];
144     #endif
145 
146     // current exception being handled, for sys.exc_info()
147     #if MICROPY_PY_SYS_EXC_INFO
148     mp_obj_base_t *cur_exception;
149     #endif
150 
151     #if MICROPY_PY_SYS_ATEXIT
152     // exposed through sys.atexit function
153     mp_obj_t sys_exitfunc;
154     #endif
155 
156     // dictionary for the __main__ module
157     mp_obj_dict_t dict_main;
158 
159     // these two lists must be initialised per port, after the call to mp_init
160     mp_obj_list_t mp_sys_path_obj;
161     mp_obj_list_t mp_sys_argv_obj;
162 
163     // dictionary for overridden builtins
164     #if MICROPY_CAN_OVERRIDE_BUILTINS
165     mp_obj_dict_t *mp_module_builtins_override_dict;
166     #endif
167 
168     #if MICROPY_PERSISTENT_CODE_TRACK_RELOC_CODE
169     // An mp_obj_list_t that tracks relocated native code to prevent the GC from reclaiming them.
170     mp_obj_t track_reloc_code_list;
171     #endif
172 
173     // include any root pointers defined by a port
174     MICROPY_PORT_ROOT_POINTERS
175 
176     // root pointers for extmod
177 
178     #if MICROPY_REPL_EVENT_DRIVEN
179     vstr_t *repl_line;
180     #endif
181 
182     #if MICROPY_PY_OS_DUPTERM
183     mp_obj_t dupterm_objs[MICROPY_PY_OS_DUPTERM];
184     #endif
185 
186     #if MICROPY_PY_LWIP_SLIP
187     mp_obj_t lwip_slip_stream;
188     #endif
189 
190     #if MICROPY_VFS
191     struct _mp_vfs_mount_t *vfs_cur;
192     struct _mp_vfs_mount_t *vfs_mount_table;
193     #endif
194 
195     #if MICROPY_PY_BLUETOOTH
196     mp_obj_t bluetooth;
197     #endif
198 
199     //
200     // END ROOT POINTER SECTION
201     ////////////////////////////////////////////////////////////
202 
203     // pointer and sizes to store interned string data
204     // (qstr_last_chunk can be root pointer but is also stored in qstr pool)
205     byte *qstr_last_chunk;
206     size_t qstr_last_alloc;
207     size_t qstr_last_used;
208 
209     #if MICROPY_PY_THREAD && !MICROPY_PY_THREAD_GIL
210     // This is a global mutex used to make qstr interning thread-safe.
211     mp_thread_mutex_t qstr_mutex;
212     #endif
213 
214     #if MICROPY_ENABLE_COMPILER
215     mp_uint_t mp_optimise_value;
216     #if MICROPY_EMIT_NATIVE
217     uint8_t default_emit_opt; // one of MP_EMIT_OPT_xxx
218     #endif
219     #endif
220 
221     // size of the emergency exception buf, if it's dynamically allocated
222     #if MICROPY_ENABLE_EMERGENCY_EXCEPTION_BUF && MICROPY_EMERGENCY_EXCEPTION_BUF_SIZE == 0
223     mp_int_t mp_emergency_exception_buf_size;
224     #endif
225 
226     #if MICROPY_ENABLE_SCHEDULER
227     volatile int16_t sched_state;
228     uint8_t sched_len;
229     uint8_t sched_idx;
230     #endif
231 
232     #if MICROPY_PY_THREAD_GIL
233     // This is a global mutex used to make the VM/runtime thread-safe.
234     mp_thread_mutex_t gil_mutex;
235     #endif
236 } mp_state_vm_t;
237 
238 // This structure holds state that is specific to a given thread.
239 // Everything in this structure is scanned for root pointers.
240 typedef struct _mp_state_thread_t {
241     // Stack top at the start of program
242     char *stack_top;
243 
244     #if MICROPY_STACK_CHECK
245     size_t stack_limit;
246     #endif
247 
248     #if MICROPY_ENABLE_PYSTACK
249     uint8_t *pystack_start;
250     uint8_t *pystack_end;
251     uint8_t *pystack_cur;
252     #endif
253 
254     ////////////////////////////////////////////////////////////
255     // START ROOT POINTER SECTION
256     // Everything that needs GC scanning must start here, and
257     // is followed by state in the mp_state_vm_t structure.
258     //
259 
260     mp_obj_dict_t *dict_locals;
261     mp_obj_dict_t *dict_globals;
262 
263     nlr_buf_t *nlr_top;
264 
265     // pending exception object (MP_OBJ_NULL if not pending)
266     volatile mp_obj_t mp_pending_exception;
267 
268     // If MP_OBJ_STOP_ITERATION is propagated then this holds its argument.
269     mp_obj_t stop_iteration_arg;
270 
271     #if MICROPY_PY_SYS_SETTRACE
272     mp_obj_t prof_trace_callback;
273     bool prof_callback_is_executing;
274     struct _mp_code_state_t *current_code_state;
275     #endif
276 } mp_state_thread_t;
277 
278 // This structure combines the above 3 structures.
279 // The order of the entries are important for root pointer scanning in the GC to work.
280 typedef struct _mp_state_ctx_t {
281     mp_state_thread_t thread;
282     mp_state_vm_t vm;
283     mp_state_mem_t mem;
284 } mp_state_ctx_t;
285 
286 extern mp_state_ctx_t mp_state_ctx;
287 
288 #define MP_STATE_VM(x) (mp_state_ctx.vm.x)
289 #define MP_STATE_MEM(x) (mp_state_ctx.mem.x)
290 #define MP_STATE_MAIN_THREAD(x) (mp_state_ctx.thread.x)
291 
292 #if MICROPY_PY_THREAD
293 extern mp_state_thread_t *mp_thread_get_state(void);
294 #define MP_STATE_THREAD(x) (mp_thread_get_state()->x)
295 #else
296 #define MP_STATE_THREAD(x) (mp_state_ctx.thread.x)
297 #endif
298 
299 #endif // MICROPY_INCLUDED_PY_MPSTATE_H
300