STATIC void gc_sweep(void) { #if MICROPY_PY_GC_COLLECT_RETVAL MP_STATE_MEM(gc_collected) = 0; #endif // free unmarked heads and their tails int free_tail = 0; for (size_t block = 0; block < MP_STATE_MEM(gc_alloc_table_byte_len) * BLOCKS_PER_ATB; block++) { switch (ATB_GET_KIND(block)) { case AT_HEAD: #if MICROPY_ENABLE_FINALISER if (FTB_GET(block)) { mp_obj_base_t *obj = (mp_obj_base_t*)PTR_FROM_BLOCK(block); if (obj->type != NULL) { // if the object has a type then see if it has a __del__ method mp_obj_t dest[2]; mp_load_method_maybe(MP_OBJ_FROM_PTR(obj), MP_QSTR___del__, dest); if (dest[0] != MP_OBJ_NULL) { // load_method returned a method, execute it in a protected environment #if MICROPY_ENABLE_SCHEDULER mp_sched_lock(); #endif mp_call_function_1_protected(dest[0], dest[1]); #if MICROPY_ENABLE_SCHEDULER mp_sched_unlock(); #endif } } // clear finaliser flag FTB_CLEAR(block); } #endif free_tail = 1; DEBUG_printf("gc_sweep(%p)\n", PTR_FROM_BLOCK(block)); #if MICROPY_PY_GC_COLLECT_RETVAL MP_STATE_MEM(gc_collected)++; #endif // fall through to free the head case AT_TAIL: if (free_tail) { ATB_ANY_TO_FREE(block); #if CLEAR_ON_SWEEP memset((void*)PTR_FROM_BLOCK(block), 0, BYTES_PER_BLOCK); #endif } break; case AT_MARK: ATB_MARK_TO_HEAD(block); free_tail = 0; break; } } }
STATIC void gc_sweep(void) { mp_uint_t block; #if MICROPY_PY_GC_COLLECT_RETVAL gc_collected = 0; #endif // free unmarked heads and their tails int free_tail = 0; for (block = 0; block < gc_alloc_table_byte_len * BLOCKS_PER_ATB; block++) { switch (ATB_GET_KIND(block)) { case AT_HEAD: #if MICROPY_ENABLE_FINALISER if (FTB_GET(block)) { mp_obj_t obj = (mp_obj_t)PTR_FROM_BLOCK(block); if (((mp_obj_base_t*)obj)->type != MP_OBJ_NULL) { // if the object has a type then see if it has a __del__ method mp_obj_t dest[2]; mp_load_method_maybe(obj, MP_QSTR___del__, dest); if (dest[0] != MP_OBJ_NULL) { // load_method returned a method mp_call_method_n_kw(0, 0, dest); } } // clear finaliser flag FTB_CLEAR(block); } #endif free_tail = 1; #if MICROPY_PY_GC_COLLECT_RETVAL gc_collected++; #endif // fall through to free the head // no break - disable eclipse static analyzer warning - intentional fall through case AT_TAIL: if (free_tail) { DEBUG_printf("gc_sweep(%p)\n",PTR_FROM_BLOCK(block)); ATB_ANY_TO_FREE(block); } break; case AT_MARK: ATB_MARK_TO_HEAD(block); free_tail = 0; break; } } }
STATIC void gc_drain_stack(void) { while (gc_sp > gc_stack) { // pop the next block off the stack machine_uint_t block = *--gc_sp; // work out number of consecutive blocks in the chain starting with this one machine_uint_t n_blocks = 0; do { n_blocks += 1; } while (ATB_GET_KIND(block + n_blocks) == AT_TAIL); // check this block's children machine_uint_t *scan = (machine_uint_t*)PTR_FROM_BLOCK(block); for (machine_uint_t i = n_blocks * WORDS_PER_BLOCK; i > 0; i--, scan++) { machine_uint_t ptr2 = *scan; VERIFY_MARK_AND_PUSH(ptr2); } } }
STATIC void gc_drain_stack(void) { while (MP_STATE_MEM(gc_sp) > MP_STATE_MEM(gc_stack)) { // pop the next block off the stack size_t block = *--MP_STATE_MEM(gc_sp); // work out number of consecutive blocks in the chain starting with this one size_t n_blocks = 0; do { n_blocks += 1; } while (ATB_GET_KIND(block + n_blocks) == AT_TAIL); // check this block's children void **ptrs = (void**)PTR_FROM_BLOCK(block); for (size_t i = n_blocks * BYTES_PER_BLOCK / sizeof(void*); i > 0; i--, ptrs++) { void *ptr = *ptrs; VERIFY_MARK_AND_PUSH(ptr); } } }
// Take the given block as the topmost block on the stack. Check all it's // children: mark the unmarked child blocks and put those newly marked // blocks on the stack. When all children have been checked, pop off the // topmost block on the stack and repeat with that one. STATIC void gc_mark_subtree(size_t block) { // Start with the block passed in the argument. size_t sp = 0; for (;;) { // work out number of consecutive blocks in the chain starting with this one size_t n_blocks = 0; do { n_blocks += 1; } while (ATB_GET_KIND(block + n_blocks) == AT_TAIL); // check this block's children void **ptrs = (void**)PTR_FROM_BLOCK(block); for (size_t i = n_blocks * BYTES_PER_BLOCK / sizeof(void*); i > 0; i--, ptrs++) { void *ptr = *ptrs; if (VERIFY_PTR(ptr)) { // Mark and push this pointer size_t childblock = BLOCK_FROM_PTR(ptr); if (ATB_GET_KIND(childblock) == AT_HEAD) { // an unmarked head, mark it, and push it on gc stack TRACE_MARK(childblock, ptr); ATB_HEAD_TO_MARK(childblock); if (sp < MICROPY_ALLOC_GC_STACK_SIZE) { MP_STATE_MEM(gc_stack)[sp++] = childblock; } else { MP_STATE_MEM(gc_stack_overflow) = 1; } } } } // Are there any blocks on the stack? if (sp == 0) { break; // No, stack is empty, we're done. } // pop the next block off the stack block = MP_STATE_MEM(gc_stack)[--sp]; } }
STATIC void gc_sweep(void) { // free unmarked heads and their tails int free_tail = 0; for (machine_uint_t block = 0; block < gc_alloc_table_byte_len * BLOCKS_PER_ATB; block++) { switch (ATB_GET_KIND(block)) { case AT_HEAD: #if MICROPY_ENABLE_FINALISER if (FTB_GET(block)) { mp_obj_t obj = (mp_obj_t)PTR_FROM_BLOCK(block); if (((mp_obj_base_t*)obj)->type != MP_OBJ_NULL) { // if the object has a type then see if it has a __del__ method mp_obj_t dest[2]; mp_load_method_maybe(obj, MP_QSTR___del__, dest); if (dest[0] != MP_OBJ_NULL) { // load_method returned a method mp_call_method_n_kw(0, 0, dest); } } // clear finaliser flag FTB_CLEAR(block); } #endif free_tail = 1; // fall through to free the head case AT_TAIL: if (free_tail) { ATB_ANY_TO_FREE(block); } break; case AT_MARK: ATB_MARK_TO_HEAD(block); free_tail = 0; break; } } }
void gc_dump_alloc_table(void) { static const size_t DUMP_BYTES_PER_LINE = 64; #if !EXTENSIVE_HEAP_PROFILING // When comparing heap output we don't want to print the starting // pointer of the heap because it changes from run to run. mp_printf(&mp_plat_print, "GC memory layout; from %p:", MP_STATE_MEM(gc_pool_start)); #endif for (size_t bl = 0; bl < MP_STATE_MEM(gc_alloc_table_byte_len) * BLOCKS_PER_ATB; bl++) { if (bl % DUMP_BYTES_PER_LINE == 0) { // a new line of blocks { // check if this line contains only free blocks size_t bl2 = bl; while (bl2 < MP_STATE_MEM(gc_alloc_table_byte_len) * BLOCKS_PER_ATB && ATB_GET_KIND(bl2) == AT_FREE) { bl2++; } if (bl2 - bl >= 2 * DUMP_BYTES_PER_LINE) { // there are at least 2 lines containing only free blocks, so abbreviate their printing mp_printf(&mp_plat_print, "\n (%u lines all free)", (uint)(bl2 - bl) / DUMP_BYTES_PER_LINE); bl = bl2 & (~(DUMP_BYTES_PER_LINE - 1)); if (bl >= MP_STATE_MEM(gc_alloc_table_byte_len) * BLOCKS_PER_ATB) { // got to end of heap break; } } } // print header for new line of blocks // (the cast to uint32_t is for 16-bit ports) #if EXTENSIVE_HEAP_PROFILING mp_printf(&mp_plat_print, "\n%05x: ", (uint)((bl * BYTES_PER_BLOCK) & (uint32_t)0xfffff)); #else mp_printf(&mp_plat_print, "\n%05x: ", (uint)(PTR_FROM_BLOCK(bl) & (uint32_t)0xfffff)); #endif } int c = ' '; switch (ATB_GET_KIND(bl)) { case AT_FREE: c = '.'; break; /* this prints out if the object is reachable from BSS or STACK (for unix only) case AT_HEAD: { c = 'h'; void **ptrs = (void**)(void*)&mp_state_ctx; mp_uint_t len = offsetof(mp_state_ctx_t, vm.stack_top) / sizeof(mp_uint_t); for (mp_uint_t i = 0; i < len; i++) { mp_uint_t ptr = (mp_uint_t)ptrs[i]; if (VERIFY_PTR(ptr) && BLOCK_FROM_PTR(ptr) == bl) { c = 'B'; break; } } if (c == 'h') { ptrs = (void**)&c; len = ((mp_uint_t)MP_STATE_VM(stack_top) - (mp_uint_t)&c) / sizeof(mp_uint_t); for (mp_uint_t i = 0; i < len; i++) { mp_uint_t ptr = (mp_uint_t)ptrs[i]; if (VERIFY_PTR(ptr) && BLOCK_FROM_PTR(ptr) == bl) { c = 'S'; break; } } } break; } */ /* this prints the uPy object type of the head block */ case AT_HEAD: { void **ptr = (void**)(MP_STATE_MEM(gc_pool_start) + bl * BYTES_PER_BLOCK); if (*ptr == &mp_type_tuple) { c = 'T'; } else if (*ptr == &mp_type_list) { c = 'L'; } else if (*ptr == &mp_type_dict) { c = 'D'; } #if MICROPY_PY_BUILTINS_FLOAT else if (*ptr == &mp_type_float) { c = 'F'; } #endif else if (*ptr == &mp_type_fun_bc) { c = 'B'; } else if (*ptr == &mp_type_module) { c = 'M'; } else { c = 'h'; #if 0 // This code prints "Q" for qstr-pool data, and "q" for qstr-str // data. It can be useful to see how qstrs are being allocated, // but is disabled by default because it is very slow. for (qstr_pool_t *pool = MP_STATE_VM(last_pool); c == 'h' && pool != NULL; pool = pool->prev) { if ((qstr_pool_t*)ptr == pool) { c = 'Q'; break; } for (const byte **q = pool->qstrs, **q_top = pool->qstrs + pool->len; q < q_top; q++) { if ((const byte*)ptr == *q) { c = 'q'; break; } } } #endif } break; } case AT_TAIL: c = 't'; break; case AT_MARK: c = 'm'; break; } mp_printf(&mp_plat_print, "%c", c); } mp_print_str(&mp_plat_print, "\n"); }