diff options
Diffstat (limited to 'py')
| -rw-r--r-- | py/gc.c | 45 | ||||
| -rw-r--r-- | py/modmicropython.c | 4 | ||||
| -rw-r--r-- | py/modthread.c | 3 | ||||
| -rw-r--r-- | py/mpstate.h | 4 |
4 files changed, 30 insertions, 26 deletions
@@ -150,7 +150,7 @@ void gc_init(void *start, void *end) { MP_STATE_MEM(gc_last_free_atb_index) = 0; // unlock the GC - MP_STATE_MEM(gc_lock_depth) = 0; + MP_STATE_THREAD(gc_lock_depth) = 0; // allow auto collection MP_STATE_MEM(gc_auto_collect_enabled) = 1; @@ -174,19 +174,20 @@ void gc_init(void *start, void *end) { } void gc_lock(void) { - GC_ENTER(); - MP_STATE_MEM(gc_lock_depth)++; - GC_EXIT(); + // This does not need to be atomic or have the GC mutex because: + // - each thread has its own gc_lock_depth so there are no races between threads; + // - a hard interrupt will only change gc_lock_depth during its execution, and + // upon return will restore the value of gc_lock_depth. + MP_STATE_THREAD(gc_lock_depth)++; } void gc_unlock(void) { - GC_ENTER(); - MP_STATE_MEM(gc_lock_depth)--; - GC_EXIT(); + // This does not need to be atomic, See comment above in gc_lock. + MP_STATE_THREAD(gc_lock_depth)--; } bool gc_is_locked(void) { - return MP_STATE_MEM(gc_lock_depth) != 0; + return MP_STATE_THREAD(gc_lock_depth) != 0; } // ptr should be of type void* @@ -320,7 +321,7 @@ STATIC void gc_sweep(void) { void gc_collect_start(void) { GC_ENTER(); - MP_STATE_MEM(gc_lock_depth)++; + MP_STATE_THREAD(gc_lock_depth)++; #if MICROPY_GC_ALLOC_THRESHOLD MP_STATE_MEM(gc_alloc_amount) = 0; #endif @@ -360,13 +361,13 @@ void gc_collect_end(void) { gc_deal_with_stack_overflow(); gc_sweep(); MP_STATE_MEM(gc_last_free_atb_index) = 0; - MP_STATE_MEM(gc_lock_depth)--; + MP_STATE_THREAD(gc_lock_depth)--; GC_EXIT(); } void gc_sweep_all(void) { GC_ENTER(); - MP_STATE_MEM(gc_lock_depth)++; + MP_STATE_THREAD(gc_lock_depth)++; MP_STATE_MEM(gc_stack_overflow) = 0; gc_collect_end(); } @@ -445,14 +446,13 @@ void *gc_alloc(size_t n_bytes, unsigned int alloc_flags) { return NULL; } - GC_ENTER(); - // check if GC is locked - if (MP_STATE_MEM(gc_lock_depth) > 0) { - GC_EXIT(); + if (MP_STATE_THREAD(gc_lock_depth) > 0) { return NULL; } + GC_ENTER(); + size_t i; size_t end_block; size_t start_block; @@ -573,13 +573,13 @@ void *gc_alloc_with_finaliser(mp_uint_t n_bytes) { // force the freeing of a piece of memory // TODO: freeing here does not call finaliser void gc_free(void *ptr) { - GC_ENTER(); - if (MP_STATE_MEM(gc_lock_depth) > 0) { + if (MP_STATE_THREAD(gc_lock_depth) > 0) { // TODO how to deal with this error? - GC_EXIT(); return; } + GC_ENTER(); + DEBUG_printf("gc_free(%p)\n", ptr); if (ptr == NULL) { @@ -674,15 +674,14 @@ void *gc_realloc(void *ptr_in, size_t n_bytes, bool allow_move) { return NULL; } + if (MP_STATE_THREAD(gc_lock_depth) > 0) { + return NULL; + } + void *ptr = ptr_in; GC_ENTER(); - if (MP_STATE_MEM(gc_lock_depth) > 0) { - GC_EXIT(); - return NULL; - } - // get the GC block number corresponding to this pointer assert(VERIFY_PTR(ptr)); size_t block = BLOCK_FROM_PTR(ptr); diff --git a/py/modmicropython.c b/py/modmicropython.c index f7eadf79bd..180f7f186c 100644 --- a/py/modmicropython.c +++ b/py/modmicropython.c @@ -130,13 +130,13 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_0(mp_micropython_heap_lock_obj, mp_micropython_he STATIC mp_obj_t mp_micropython_heap_unlock(void) { gc_unlock(); - return MP_OBJ_NEW_SMALL_INT(MP_STATE_MEM(gc_lock_depth)); + return MP_OBJ_NEW_SMALL_INT(MP_STATE_THREAD(gc_lock_depth)); } STATIC MP_DEFINE_CONST_FUN_OBJ_0(mp_micropython_heap_unlock_obj, mp_micropython_heap_unlock); #if MICROPY_PY_MICROPYTHON_HEAP_LOCKED STATIC mp_obj_t mp_micropython_heap_locked(void) { - return MP_OBJ_NEW_SMALL_INT(MP_STATE_MEM(gc_lock_depth)); + return MP_OBJ_NEW_SMALL_INT(MP_STATE_THREAD(gc_lock_depth)); } STATIC MP_DEFINE_CONST_FUN_OBJ_0(mp_micropython_heap_locked_obj, mp_micropython_heap_locked); #endif diff --git a/py/modthread.c b/py/modthread.c index 1306dc642b..64fbb3f198 100644 --- a/py/modthread.c +++ b/py/modthread.c @@ -171,6 +171,9 @@ STATIC void *thread_entry(void *args_in) { mp_pystack_init(mini_pystack, &mini_pystack[128]); #endif + // The GC starts off unlocked on this thread. + ts.gc_lock_depth = 0; + // set locals and globals from the calling context mp_locals_set(args->dict_locals); mp_globals_set(args->dict_globals); diff --git a/py/mpstate.h b/py/mpstate.h index 2519c77e2d..a0e3d4f143 100644 --- a/py/mpstate.h +++ b/py/mpstate.h @@ -80,7 +80,6 @@ typedef struct _mp_state_mem_t { int gc_stack_overflow; MICROPY_GC_STACK_ENTRY_TYPE gc_stack[MICROPY_ALLOC_GC_STACK_SIZE]; - uint16_t gc_lock_depth; // This variable controls auto garbage collection. If set to 0 then the // GC won't automatically run when gc_alloc can't find enough blocks. But @@ -253,6 +252,9 @@ typedef struct _mp_state_thread_t { uint8_t *pystack_cur; #endif + // Locking of the GC is done per thread. + uint16_t gc_lock_depth; + //////////////////////////////////////////////////////////// // START ROOT POINTER SECTION // Everything that needs GC scanning must start here, and |