kopia lustrzana https://github.com/micropython/micropython
1355 wiersze
47 KiB
C
1355 wiersze
47 KiB
C
/*
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* This file is part of the MicroPython project, http://micropython.org/
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*
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* The MIT License (MIT)
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*
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* Copyright (c) 2013, 2014 Damien P. George
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* Copyright (c) 2014 Paul Sokolovsky
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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* in the Software without restriction, including without limitation the rights
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* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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* THE SOFTWARE.
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*/
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#include <assert.h>
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#include <stdio.h>
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#include <string.h>
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#include "py/gc.h"
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#include "py/runtime.h"
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#if MICROPY_DEBUG_VALGRIND
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#include <valgrind/memcheck.h>
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#endif
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#if MICROPY_ENABLE_GC
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#if MICROPY_DEBUG_VERBOSE // print debugging info
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#define DEBUG_PRINT (1)
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#define DEBUG_printf DEBUG_printf
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#else // don't print debugging info
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#define DEBUG_PRINT (0)
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#define DEBUG_printf(...) (void)0
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#endif
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// make this 1 to dump the heap each time it changes
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#define EXTENSIVE_HEAP_PROFILING (0)
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// make this 1 to zero out swept memory to more eagerly
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// detect untraced object still in use
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#define CLEAR_ON_SWEEP (0)
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#define WORDS_PER_BLOCK ((MICROPY_BYTES_PER_GC_BLOCK) / MP_BYTES_PER_OBJ_WORD)
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#define BYTES_PER_BLOCK (MICROPY_BYTES_PER_GC_BLOCK)
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// ATB = allocation table byte
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// 0b00 = FREE -- free block
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// 0b01 = HEAD -- head of a chain of blocks
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// 0b10 = TAIL -- in the tail of a chain of blocks
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// 0b11 = MARK -- marked head block
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#define AT_FREE (0)
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#define AT_HEAD (1)
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#define AT_TAIL (2)
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#define AT_MARK (3)
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#define BLOCKS_PER_ATB (4)
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#define ATB_MASK_0 (0x03)
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#define ATB_MASK_1 (0x0c)
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#define ATB_MASK_2 (0x30)
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#define ATB_MASK_3 (0xc0)
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#define ATB_0_IS_FREE(a) (((a) & ATB_MASK_0) == 0)
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#define ATB_1_IS_FREE(a) (((a) & ATB_MASK_1) == 0)
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#define ATB_2_IS_FREE(a) (((a) & ATB_MASK_2) == 0)
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#define ATB_3_IS_FREE(a) (((a) & ATB_MASK_3) == 0)
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#if MICROPY_GC_SPLIT_HEAP
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#define NEXT_AREA(area) ((area)->next)
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#else
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#define NEXT_AREA(area) (NULL)
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#endif
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#define BLOCK_SHIFT(block) (2 * ((block) & (BLOCKS_PER_ATB - 1)))
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#define ATB_GET_KIND(area, block) (((area)->gc_alloc_table_start[(block) / BLOCKS_PER_ATB] >> BLOCK_SHIFT(block)) & 3)
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#define ATB_ANY_TO_FREE(area, block) do { area->gc_alloc_table_start[(block) / BLOCKS_PER_ATB] &= (~(AT_MARK << BLOCK_SHIFT(block))); } while (0)
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#define ATB_FREE_TO_HEAD(area, block) do { area->gc_alloc_table_start[(block) / BLOCKS_PER_ATB] |= (AT_HEAD << BLOCK_SHIFT(block)); } while (0)
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#define ATB_FREE_TO_TAIL(area, block) do { area->gc_alloc_table_start[(block) / BLOCKS_PER_ATB] |= (AT_TAIL << BLOCK_SHIFT(block)); } while (0)
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#define ATB_HEAD_TO_MARK(area, block) do { area->gc_alloc_table_start[(block) / BLOCKS_PER_ATB] |= (AT_MARK << BLOCK_SHIFT(block)); } while (0)
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#define ATB_MARK_TO_HEAD(area, block) do { area->gc_alloc_table_start[(block) / BLOCKS_PER_ATB] &= (~(AT_TAIL << BLOCK_SHIFT(block))); } while (0)
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#define BLOCK_FROM_PTR(area, ptr) (((byte *)(ptr) - area->gc_pool_start) / BYTES_PER_BLOCK)
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#define PTR_FROM_BLOCK(area, block) (((block) * BYTES_PER_BLOCK + (uintptr_t)area->gc_pool_start))
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// After the ATB, there must be a byte filled with AT_FREE so that gc_mark_tree
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// cannot erroneously conclude that a block extends past the end of the GC heap
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// due to bit patterns in the FTB (or first block, if finalizers are disabled)
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// being interpreted as AT_TAIL.
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#define ALLOC_TABLE_GAP_BYTE (1)
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#if MICROPY_ENABLE_FINALISER
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// FTB = finaliser table byte
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// if set, then the corresponding block may have a finaliser
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#define BLOCKS_PER_FTB (8)
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#define FTB_GET(area, block) ((area->gc_finaliser_table_start[(block) / BLOCKS_PER_FTB] >> ((block) & 7)) & 1)
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#define FTB_SET(area, block) do { area->gc_finaliser_table_start[(block) / BLOCKS_PER_FTB] |= (1 << ((block) & 7)); } while (0)
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#define FTB_CLEAR(area, block) do { area->gc_finaliser_table_start[(block) / BLOCKS_PER_FTB] &= (~(1 << ((block) & 7))); } while (0)
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#endif
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#if MICROPY_PY_THREAD && !MICROPY_PY_THREAD_GIL
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#define GC_ENTER() mp_thread_mutex_lock(&MP_STATE_MEM(gc_mutex), 1)
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#define GC_EXIT() mp_thread_mutex_unlock(&MP_STATE_MEM(gc_mutex))
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#else
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#define GC_ENTER()
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#define GC_EXIT()
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#endif
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// TODO waste less memory; currently requires that all entries in alloc_table have a corresponding block in pool
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static void gc_setup_area(mp_state_mem_area_t *area, void *start, void *end) {
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// calculate parameters for GC (T=total, A=alloc table, F=finaliser table, P=pool; all in bytes):
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// T = A + F + P
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// F = A * BLOCKS_PER_ATB / BLOCKS_PER_FTB
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// P = A * BLOCKS_PER_ATB * BYTES_PER_BLOCK
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// => T = A * (1 + BLOCKS_PER_ATB / BLOCKS_PER_FTB + BLOCKS_PER_ATB * BYTES_PER_BLOCK)
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size_t total_byte_len = (byte *)end - (byte *)start;
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#if MICROPY_ENABLE_FINALISER
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area->gc_alloc_table_byte_len = (total_byte_len - ALLOC_TABLE_GAP_BYTE)
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* MP_BITS_PER_BYTE
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/ (
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MP_BITS_PER_BYTE
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+ MP_BITS_PER_BYTE * BLOCKS_PER_ATB / BLOCKS_PER_FTB
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+ MP_BITS_PER_BYTE * BLOCKS_PER_ATB * BYTES_PER_BLOCK
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);
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#else
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area->gc_alloc_table_byte_len = (total_byte_len - ALLOC_TABLE_GAP_BYTE) / (1 + MP_BITS_PER_BYTE / 2 * BYTES_PER_BLOCK);
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#endif
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area->gc_alloc_table_start = (byte *)start;
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#if MICROPY_ENABLE_FINALISER
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size_t gc_finaliser_table_byte_len = (area->gc_alloc_table_byte_len * BLOCKS_PER_ATB + BLOCKS_PER_FTB - 1) / BLOCKS_PER_FTB;
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area->gc_finaliser_table_start = area->gc_alloc_table_start + area->gc_alloc_table_byte_len + ALLOC_TABLE_GAP_BYTE;
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#endif
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size_t gc_pool_block_len = area->gc_alloc_table_byte_len * BLOCKS_PER_ATB;
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area->gc_pool_start = (byte *)end - gc_pool_block_len * BYTES_PER_BLOCK;
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area->gc_pool_end = end;
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#if MICROPY_ENABLE_FINALISER
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assert(area->gc_pool_start >= area->gc_finaliser_table_start + gc_finaliser_table_byte_len);
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#endif
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#if MICROPY_ENABLE_FINALISER
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// clear ATB's and FTB's
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memset(area->gc_alloc_table_start, 0, gc_finaliser_table_byte_len + area->gc_alloc_table_byte_len + ALLOC_TABLE_GAP_BYTE);
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#else
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// clear ATB's
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memset(area->gc_alloc_table_start, 0, area->gc_alloc_table_byte_len + ALLOC_TABLE_GAP_BYTE);
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#endif
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area->gc_last_free_atb_index = 0;
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area->gc_last_used_block = 0;
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#if MICROPY_GC_SPLIT_HEAP
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area->next = NULL;
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#endif
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DEBUG_printf("GC layout:\n");
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DEBUG_printf(" alloc table at %p, length " UINT_FMT " bytes, "
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UINT_FMT " blocks\n",
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area->gc_alloc_table_start, area->gc_alloc_table_byte_len,
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area->gc_alloc_table_byte_len * BLOCKS_PER_ATB);
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#if MICROPY_ENABLE_FINALISER
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DEBUG_printf(" finaliser table at %p, length " UINT_FMT " bytes, "
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UINT_FMT " blocks\n", area->gc_finaliser_table_start,
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gc_finaliser_table_byte_len,
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gc_finaliser_table_byte_len * BLOCKS_PER_FTB);
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#endif
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DEBUG_printf(" pool at %p, length " UINT_FMT " bytes, "
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UINT_FMT " blocks\n", area->gc_pool_start,
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gc_pool_block_len * BYTES_PER_BLOCK, gc_pool_block_len);
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}
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void gc_init(void *start, void *end) {
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// align end pointer on block boundary
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end = (void *)((uintptr_t)end & (~(BYTES_PER_BLOCK - 1)));
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DEBUG_printf("Initializing GC heap: %p..%p = " UINT_FMT " bytes\n", start, end, (byte *)end - (byte *)start);
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gc_setup_area(&MP_STATE_MEM(area), start, end);
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// set last free ATB index to start of heap
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#if MICROPY_GC_SPLIT_HEAP
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MP_STATE_MEM(gc_last_free_area) = &MP_STATE_MEM(area);
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#endif
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// unlock the GC
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MP_STATE_THREAD(gc_lock_depth) = 0;
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// allow auto collection
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MP_STATE_MEM(gc_auto_collect_enabled) = 1;
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#if MICROPY_GC_ALLOC_THRESHOLD
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// by default, maxuint for gc threshold, effectively turning gc-by-threshold off
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MP_STATE_MEM(gc_alloc_threshold) = (size_t)-1;
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MP_STATE_MEM(gc_alloc_amount) = 0;
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#endif
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#if MICROPY_PY_THREAD && !MICROPY_PY_THREAD_GIL
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mp_thread_mutex_init(&MP_STATE_MEM(gc_mutex));
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#endif
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}
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#if MICROPY_GC_SPLIT_HEAP
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void gc_add(void *start, void *end) {
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// Place the area struct at the start of the area.
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mp_state_mem_area_t *area = (mp_state_mem_area_t *)start;
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start = (void *)((uintptr_t)start + sizeof(mp_state_mem_area_t));
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end = (void *)((uintptr_t)end & (~(BYTES_PER_BLOCK - 1)));
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DEBUG_printf("Adding GC heap: %p..%p = " UINT_FMT " bytes\n", start, end, (byte *)end - (byte *)start);
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// Init this area
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gc_setup_area(area, start, end);
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// Find the last registered area in the linked list
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mp_state_mem_area_t *prev_area = &MP_STATE_MEM(area);
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while (prev_area->next != NULL) {
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prev_area = prev_area->next;
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}
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// Add this area to the linked list
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prev_area->next = area;
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}
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#if MICROPY_GC_SPLIT_HEAP_AUTO
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// Try to automatically add a heap area large enough to fulfill 'failed_alloc'.
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static bool gc_try_add_heap(size_t failed_alloc) {
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// 'needed' is the size of a heap large enough to hold failed_alloc, with
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// the additional metadata overheads as calculated in gc_setup_area().
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//
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// Rather than reproduce all of that logic here, we approximate that adding
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// (13/512) is enough overhead for sufficiently large heap areas (the
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// overhead converges to 3/128, but there's some fixed overhead and some
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// rounding up of partial block sizes).
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size_t needed = failed_alloc + MAX(2048, failed_alloc * 13 / 512);
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size_t avail = gc_get_max_new_split();
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DEBUG_printf("gc_try_add_heap failed_alloc " UINT_FMT ", "
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"needed " UINT_FMT ", avail " UINT_FMT " bytes \n",
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failed_alloc,
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needed,
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avail);
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if (avail < needed) {
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// Can't fit this allocation, or system heap has nearly run out anyway
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return false;
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}
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// Deciding how much to grow the total heap by each time is tricky:
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//
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// - Grow by too small amounts, leads to heap fragmentation issues.
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//
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// - Grow by too large amounts, may lead to system heap running out of
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// space.
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//
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// Currently, this implementation is:
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//
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// - At minimum, aim to double the total heap size each time we add a new
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// heap. i.e. without any large single allocations, total size will be
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// 64KB -> 128KB -> 256KB -> 512KB -> 1MB, etc
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//
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// - If the failed allocation is too large to fit in that size, the new
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// heap is made exactly large enough for that allocation. Future growth
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// will double the total heap size again.
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//
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// - If the new heap won't fit in the available free space, add the largest
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// new heap that will fit (this may lead to failed system heap allocations
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// elsewhere, but some allocation will likely fail in this circumstance!)
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// Compute total number of blocks in the current heap.
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size_t total_blocks = 0;
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for (mp_state_mem_area_t *area = &MP_STATE_MEM(area);
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area != NULL;
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area = NEXT_AREA(area)) {
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total_blocks += area->gc_alloc_table_byte_len * BLOCKS_PER_ATB;
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}
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// Compute bytes needed to build a heap with total_blocks blocks.
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size_t total_heap =
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total_blocks / BLOCKS_PER_ATB
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#if MICROPY_ENABLE_FINALISER
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+ total_blocks / BLOCKS_PER_FTB
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#endif
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+ total_blocks * BYTES_PER_BLOCK
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+ ALLOC_TABLE_GAP_BYTE
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+ sizeof(mp_state_mem_area_t);
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// Round up size to the nearest multiple of BYTES_PER_BLOCK.
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total_heap = (total_heap + BYTES_PER_BLOCK - 1) & (~(BYTES_PER_BLOCK - 1));
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DEBUG_printf("total_heap " UINT_FMT " bytes\n", total_heap);
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size_t to_alloc = MIN(avail, MAX(total_heap, needed));
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mp_state_mem_area_t *new_heap = MP_PLAT_ALLOC_HEAP(to_alloc);
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DEBUG_printf("MP_PLAT_ALLOC_HEAP " UINT_FMT " = %p\n",
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to_alloc, new_heap);
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if (new_heap == NULL) {
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// This should only fail:
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// - In a threaded environment if another thread has
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// allocated while this function ran.
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// - If there is a bug in gc_get_max_new_split().
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return false;
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}
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gc_add(new_heap, (void *)new_heap + to_alloc);
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return true;
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}
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#endif
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#endif
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void gc_lock(void) {
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// This does not need to be atomic or have the GC mutex because:
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// - each thread has its own gc_lock_depth so there are no races between threads;
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// - a hard interrupt will only change gc_lock_depth during its execution, and
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// upon return will restore the value of gc_lock_depth.
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MP_STATE_THREAD(gc_lock_depth)++;
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}
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void gc_unlock(void) {
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// This does not need to be atomic, See comment above in gc_lock.
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MP_STATE_THREAD(gc_lock_depth)--;
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}
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bool gc_is_locked(void) {
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return MP_STATE_THREAD(gc_lock_depth) != 0;
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}
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#if MICROPY_GC_SPLIT_HEAP
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// Returns the area to which this pointer belongs, or NULL if it isn't
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// allocated on the GC-managed heap.
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static inline mp_state_mem_area_t *gc_get_ptr_area(const void *ptr) {
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if (((uintptr_t)(ptr) & (BYTES_PER_BLOCK - 1)) != 0) { // must be aligned on a block
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return NULL;
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}
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for (mp_state_mem_area_t *area = &MP_STATE_MEM(area); area != NULL; area = NEXT_AREA(area)) {
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if (ptr >= (void *)area->gc_pool_start // must be above start of pool
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&& ptr < (void *)area->gc_pool_end) { // must be below end of pool
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return area;
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}
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}
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return NULL;
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}
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#endif
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// ptr should be of type void*
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#define VERIFY_PTR(ptr) ( \
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((uintptr_t)(ptr) & (BYTES_PER_BLOCK - 1)) == 0 /* must be aligned on a block */ \
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&& ptr >= (void *)MP_STATE_MEM(area).gc_pool_start /* must be above start of pool */ \
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&& ptr < (void *)MP_STATE_MEM(area).gc_pool_end /* must be below end of pool */ \
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)
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#ifndef TRACE_MARK
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#if DEBUG_PRINT
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#define TRACE_MARK(block, ptr) DEBUG_printf("gc_mark(%p)\n", ptr)
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#else
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#define TRACE_MARK(block, ptr)
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#endif
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#endif
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// Take the given block as the topmost block on the stack. Check all it's
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// children: mark the unmarked child blocks and put those newly marked
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// blocks on the stack. When all children have been checked, pop off the
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// topmost block on the stack and repeat with that one.
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#if MICROPY_GC_SPLIT_HEAP
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static void gc_mark_subtree(mp_state_mem_area_t *area, size_t block)
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#else
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static void gc_mark_subtree(size_t block)
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#endif
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{
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// Start with the block passed in the argument.
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size_t sp = 0;
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for (;;) {
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#if !MICROPY_GC_SPLIT_HEAP
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mp_state_mem_area_t *area = &MP_STATE_MEM(area);
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#endif
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// work out number of consecutive blocks in the chain starting with this one
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size_t n_blocks = 0;
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do {
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n_blocks += 1;
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} while (ATB_GET_KIND(area, block + n_blocks) == AT_TAIL);
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// check that the consecutive blocks didn't overflow past the end of the area
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assert(area->gc_pool_start + (block + n_blocks) * BYTES_PER_BLOCK <= area->gc_pool_end);
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// check this block's children
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void **ptrs = (void **)PTR_FROM_BLOCK(area, block);
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for (size_t i = n_blocks * BYTES_PER_BLOCK / sizeof(void *); i > 0; i--, ptrs++) {
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MICROPY_GC_HOOK_LOOP(i);
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void *ptr = *ptrs;
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// If this is a heap pointer that hasn't been marked, mark it and push
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// it's children to the stack.
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#if MICROPY_GC_SPLIT_HEAP
|
|
mp_state_mem_area_t *ptr_area = gc_get_ptr_area(ptr);
|
|
if (!ptr_area) {
|
|
// Not a heap-allocated pointer (might even be random data).
|
|
continue;
|
|
}
|
|
#else
|
|
if (!VERIFY_PTR(ptr)) {
|
|
continue;
|
|
}
|
|
mp_state_mem_area_t *ptr_area = area;
|
|
#endif
|
|
size_t ptr_block = BLOCK_FROM_PTR(ptr_area, ptr);
|
|
if (ATB_GET_KIND(ptr_area, ptr_block) != AT_HEAD) {
|
|
// This block is already marked.
|
|
continue;
|
|
}
|
|
// An unmarked head. Mark it, and push it on gc stack.
|
|
TRACE_MARK(ptr_block, ptr);
|
|
ATB_HEAD_TO_MARK(ptr_area, ptr_block);
|
|
if (sp < MICROPY_ALLOC_GC_STACK_SIZE) {
|
|
MP_STATE_MEM(gc_block_stack)[sp] = ptr_block;
|
|
#if MICROPY_GC_SPLIT_HEAP
|
|
MP_STATE_MEM(gc_area_stack)[sp] = ptr_area;
|
|
#endif
|
|
sp += 1;
|
|
} 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
|
|
sp -= 1;
|
|
block = MP_STATE_MEM(gc_block_stack)[sp];
|
|
#if MICROPY_GC_SPLIT_HEAP
|
|
area = MP_STATE_MEM(gc_area_stack)[sp];
|
|
#endif
|
|
}
|
|
}
|
|
|
|
static void gc_deal_with_stack_overflow(void) {
|
|
while (MP_STATE_MEM(gc_stack_overflow)) {
|
|
MP_STATE_MEM(gc_stack_overflow) = 0;
|
|
|
|
// scan entire memory looking for blocks which have been marked but not their children
|
|
for (mp_state_mem_area_t *area = &MP_STATE_MEM(area); area != NULL; area = NEXT_AREA(area)) {
|
|
for (size_t block = 0; block < area->gc_alloc_table_byte_len * BLOCKS_PER_ATB; block++) {
|
|
MICROPY_GC_HOOK_LOOP(block);
|
|
// trace (again) if mark bit set
|
|
if (ATB_GET_KIND(area, block) == AT_MARK) {
|
|
#if MICROPY_GC_SPLIT_HEAP
|
|
gc_mark_subtree(area, block);
|
|
#else
|
|
gc_mark_subtree(block);
|
|
#endif
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
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;
|
|
#if MICROPY_GC_SPLIT_HEAP_AUTO
|
|
mp_state_mem_area_t *prev_area = NULL;
|
|
#endif
|
|
for (mp_state_mem_area_t *area = &MP_STATE_MEM(area); area != NULL; area = NEXT_AREA(area)) {
|
|
size_t end_block = area->gc_alloc_table_byte_len * BLOCKS_PER_ATB;
|
|
if (area->gc_last_used_block < end_block) {
|
|
end_block = area->gc_last_used_block + 1;
|
|
}
|
|
|
|
size_t last_used_block = 0;
|
|
|
|
for (size_t block = 0; block < end_block; block++) {
|
|
MICROPY_GC_HOOK_LOOP(block);
|
|
switch (ATB_GET_KIND(area, block)) {
|
|
case AT_HEAD:
|
|
#if MICROPY_ENABLE_FINALISER
|
|
if (FTB_GET(area, block)) {
|
|
mp_obj_base_t *obj = (mp_obj_base_t *)PTR_FROM_BLOCK(area, 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(area, block);
|
|
}
|
|
#endif
|
|
free_tail = 1;
|
|
DEBUG_printf("gc_sweep(%p)\n", (void *)PTR_FROM_BLOCK(area, block));
|
|
#if MICROPY_PY_GC_COLLECT_RETVAL
|
|
MP_STATE_MEM(gc_collected)++;
|
|
#endif
|
|
// fall through to free the head
|
|
MP_FALLTHROUGH
|
|
|
|
case AT_TAIL:
|
|
if (free_tail) {
|
|
ATB_ANY_TO_FREE(area, block);
|
|
#if CLEAR_ON_SWEEP
|
|
memset((void *)PTR_FROM_BLOCK(area, block), 0, BYTES_PER_BLOCK);
|
|
#endif
|
|
} else {
|
|
last_used_block = block;
|
|
}
|
|
break;
|
|
|
|
case AT_MARK:
|
|
ATB_MARK_TO_HEAD(area, block);
|
|
free_tail = 0;
|
|
last_used_block = block;
|
|
break;
|
|
}
|
|
}
|
|
|
|
area->gc_last_used_block = last_used_block;
|
|
|
|
#if MICROPY_GC_SPLIT_HEAP_AUTO
|
|
// Free any empty area, aside from the first one
|
|
if (last_used_block == 0 && prev_area != NULL) {
|
|
DEBUG_printf("gc_sweep free empty area %p\n", area);
|
|
NEXT_AREA(prev_area) = NEXT_AREA(area);
|
|
MP_PLAT_FREE_HEAP(area);
|
|
area = prev_area;
|
|
}
|
|
prev_area = area;
|
|
#endif
|
|
}
|
|
}
|
|
|
|
void gc_collect_start(void) {
|
|
GC_ENTER();
|
|
MP_STATE_THREAD(gc_lock_depth)++;
|
|
#if MICROPY_GC_ALLOC_THRESHOLD
|
|
MP_STATE_MEM(gc_alloc_amount) = 0;
|
|
#endif
|
|
MP_STATE_MEM(gc_stack_overflow) = 0;
|
|
|
|
// Trace root pointers. This relies on the root pointers being organised
|
|
// correctly in the mp_state_ctx structure. We scan nlr_top, dict_locals,
|
|
// dict_globals, then the root pointer section of mp_state_vm.
|
|
void **ptrs = (void **)(void *)&mp_state_ctx;
|
|
size_t root_start = offsetof(mp_state_ctx_t, thread.dict_locals);
|
|
size_t root_end = offsetof(mp_state_ctx_t, vm.qstr_last_chunk);
|
|
gc_collect_root(ptrs + root_start / sizeof(void *), (root_end - root_start) / sizeof(void *));
|
|
|
|
#if MICROPY_ENABLE_PYSTACK
|
|
// Trace root pointers from the Python stack.
|
|
ptrs = (void **)(void *)MP_STATE_THREAD(pystack_start);
|
|
gc_collect_root(ptrs, (MP_STATE_THREAD(pystack_cur) - MP_STATE_THREAD(pystack_start)) / sizeof(void *));
|
|
#endif
|
|
}
|
|
|
|
// Address sanitizer needs to know that the access to ptrs[i] must always be
|
|
// considered OK, even if it's a load from an address that would normally be
|
|
// prohibited (due to being undefined, in a red zone, etc).
|
|
#if defined(__GNUC__) && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 8))
|
|
__attribute__((no_sanitize_address))
|
|
#endif
|
|
static void *gc_get_ptr(void **ptrs, int i) {
|
|
#if MICROPY_DEBUG_VALGRIND
|
|
if (!VALGRIND_CHECK_MEM_IS_ADDRESSABLE(&ptrs[i], sizeof(*ptrs))) {
|
|
return NULL;
|
|
}
|
|
#endif
|
|
return ptrs[i];
|
|
}
|
|
|
|
void gc_collect_root(void **ptrs, size_t len) {
|
|
#if !MICROPY_GC_SPLIT_HEAP
|
|
mp_state_mem_area_t *area = &MP_STATE_MEM(area);
|
|
#endif
|
|
for (size_t i = 0; i < len; i++) {
|
|
MICROPY_GC_HOOK_LOOP(i);
|
|
void *ptr = gc_get_ptr(ptrs, i);
|
|
#if MICROPY_GC_SPLIT_HEAP
|
|
mp_state_mem_area_t *area = gc_get_ptr_area(ptr);
|
|
if (!area) {
|
|
continue;
|
|
}
|
|
#else
|
|
if (!VERIFY_PTR(ptr)) {
|
|
continue;
|
|
}
|
|
#endif
|
|
size_t block = BLOCK_FROM_PTR(area, ptr);
|
|
if (ATB_GET_KIND(area, block) == AT_HEAD) {
|
|
// An unmarked head: mark it, and mark all its children
|
|
ATB_HEAD_TO_MARK(area, block);
|
|
#if MICROPY_GC_SPLIT_HEAP
|
|
gc_mark_subtree(area, block);
|
|
#else
|
|
gc_mark_subtree(block);
|
|
#endif
|
|
}
|
|
}
|
|
}
|
|
|
|
void gc_collect_end(void) {
|
|
gc_deal_with_stack_overflow();
|
|
gc_sweep();
|
|
#if MICROPY_GC_SPLIT_HEAP
|
|
MP_STATE_MEM(gc_last_free_area) = &MP_STATE_MEM(area);
|
|
#endif
|
|
for (mp_state_mem_area_t *area = &MP_STATE_MEM(area); area != NULL; area = NEXT_AREA(area)) {
|
|
area->gc_last_free_atb_index = 0;
|
|
}
|
|
MP_STATE_THREAD(gc_lock_depth)--;
|
|
GC_EXIT();
|
|
}
|
|
|
|
void gc_sweep_all(void) {
|
|
GC_ENTER();
|
|
MP_STATE_THREAD(gc_lock_depth)++;
|
|
MP_STATE_MEM(gc_stack_overflow) = 0;
|
|
gc_collect_end();
|
|
}
|
|
|
|
void gc_info(gc_info_t *info) {
|
|
GC_ENTER();
|
|
info->total = 0;
|
|
info->used = 0;
|
|
info->free = 0;
|
|
info->max_free = 0;
|
|
info->num_1block = 0;
|
|
info->num_2block = 0;
|
|
info->max_block = 0;
|
|
for (mp_state_mem_area_t *area = &MP_STATE_MEM(area); area != NULL; area = NEXT_AREA(area)) {
|
|
bool finish = false;
|
|
info->total += area->gc_pool_end - area->gc_pool_start;
|
|
for (size_t block = 0, len = 0, len_free = 0; !finish;) {
|
|
MICROPY_GC_HOOK_LOOP(block);
|
|
size_t kind = ATB_GET_KIND(area, block);
|
|
switch (kind) {
|
|
case AT_FREE:
|
|
info->free += 1;
|
|
len_free += 1;
|
|
len = 0;
|
|
break;
|
|
|
|
case AT_HEAD:
|
|
info->used += 1;
|
|
len = 1;
|
|
break;
|
|
|
|
case AT_TAIL:
|
|
info->used += 1;
|
|
len += 1;
|
|
break;
|
|
|
|
case AT_MARK:
|
|
// shouldn't happen
|
|
break;
|
|
}
|
|
|
|
block++;
|
|
finish = (block == area->gc_alloc_table_byte_len * BLOCKS_PER_ATB);
|
|
// Get next block type if possible
|
|
if (!finish) {
|
|
kind = ATB_GET_KIND(area, block);
|
|
}
|
|
|
|
if (finish || kind == AT_FREE || kind == AT_HEAD) {
|
|
if (len == 1) {
|
|
info->num_1block += 1;
|
|
} else if (len == 2) {
|
|
info->num_2block += 1;
|
|
}
|
|
if (len > info->max_block) {
|
|
info->max_block = len;
|
|
}
|
|
if (finish || kind == AT_HEAD) {
|
|
if (len_free > info->max_free) {
|
|
info->max_free = len_free;
|
|
}
|
|
len_free = 0;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
info->used *= BYTES_PER_BLOCK;
|
|
info->free *= BYTES_PER_BLOCK;
|
|
|
|
#if MICROPY_GC_SPLIT_HEAP_AUTO
|
|
info->max_new_split = gc_get_max_new_split();
|
|
#endif
|
|
|
|
GC_EXIT();
|
|
}
|
|
|
|
void *gc_alloc(size_t n_bytes, unsigned int alloc_flags) {
|
|
bool has_finaliser = alloc_flags & GC_ALLOC_FLAG_HAS_FINALISER;
|
|
size_t n_blocks = ((n_bytes + BYTES_PER_BLOCK - 1) & (~(BYTES_PER_BLOCK - 1))) / BYTES_PER_BLOCK;
|
|
DEBUG_printf("gc_alloc(" UINT_FMT " bytes -> " UINT_FMT " blocks)\n", n_bytes, n_blocks);
|
|
|
|
// check for 0 allocation
|
|
if (n_blocks == 0) {
|
|
return NULL;
|
|
}
|
|
|
|
// check if GC is locked
|
|
if (MP_STATE_THREAD(gc_lock_depth) > 0) {
|
|
return NULL;
|
|
}
|
|
|
|
GC_ENTER();
|
|
|
|
mp_state_mem_area_t *area;
|
|
size_t i;
|
|
size_t end_block;
|
|
size_t start_block;
|
|
size_t n_free;
|
|
int collected = !MP_STATE_MEM(gc_auto_collect_enabled);
|
|
#if MICROPY_GC_SPLIT_HEAP_AUTO
|
|
bool added = false;
|
|
#endif
|
|
|
|
#if MICROPY_GC_ALLOC_THRESHOLD
|
|
if (!collected && MP_STATE_MEM(gc_alloc_amount) >= MP_STATE_MEM(gc_alloc_threshold)) {
|
|
GC_EXIT();
|
|
gc_collect();
|
|
collected = 1;
|
|
GC_ENTER();
|
|
}
|
|
#endif
|
|
|
|
for (;;) {
|
|
|
|
#if MICROPY_GC_SPLIT_HEAP
|
|
area = MP_STATE_MEM(gc_last_free_area);
|
|
#else
|
|
area = &MP_STATE_MEM(area);
|
|
#endif
|
|
|
|
// look for a run of n_blocks available blocks
|
|
for (; area != NULL; area = NEXT_AREA(area), i = 0) {
|
|
n_free = 0;
|
|
for (i = area->gc_last_free_atb_index; i < area->gc_alloc_table_byte_len; i++) {
|
|
MICROPY_GC_HOOK_LOOP(i);
|
|
byte a = area->gc_alloc_table_start[i];
|
|
// *FORMAT-OFF*
|
|
if (ATB_0_IS_FREE(a)) { if (++n_free >= n_blocks) { i = i * BLOCKS_PER_ATB + 0; goto found; } } else { n_free = 0; }
|
|
if (ATB_1_IS_FREE(a)) { if (++n_free >= n_blocks) { i = i * BLOCKS_PER_ATB + 1; goto found; } } else { n_free = 0; }
|
|
if (ATB_2_IS_FREE(a)) { if (++n_free >= n_blocks) { i = i * BLOCKS_PER_ATB + 2; goto found; } } else { n_free = 0; }
|
|
if (ATB_3_IS_FREE(a)) { if (++n_free >= n_blocks) { i = i * BLOCKS_PER_ATB + 3; goto found; } } else { n_free = 0; }
|
|
// *FORMAT-ON*
|
|
}
|
|
|
|
// No free blocks found on this heap. Mark this heap as
|
|
// filled, so we won't try to find free space here again until
|
|
// space is freed.
|
|
#if MICROPY_GC_SPLIT_HEAP
|
|
if (n_blocks == 1) {
|
|
area->gc_last_free_atb_index = (i + 1) / BLOCKS_PER_ATB; // or (size_t)-1
|
|
}
|
|
#endif
|
|
}
|
|
|
|
GC_EXIT();
|
|
// nothing found!
|
|
if (collected) {
|
|
#if MICROPY_GC_SPLIT_HEAP_AUTO
|
|
if (!added && gc_try_add_heap(n_bytes)) {
|
|
added = true;
|
|
continue;
|
|
}
|
|
#endif
|
|
return NULL;
|
|
}
|
|
DEBUG_printf("gc_alloc(" UINT_FMT "): no free mem, triggering GC\n", n_bytes);
|
|
gc_collect();
|
|
collected = 1;
|
|
GC_ENTER();
|
|
}
|
|
|
|
// found, ending at block i inclusive
|
|
found:
|
|
// get starting and end blocks, both inclusive
|
|
end_block = i;
|
|
start_block = i - n_free + 1;
|
|
|
|
// Set last free ATB index to block after last block we found, for start of
|
|
// next scan. To reduce fragmentation, we only do this if we were looking
|
|
// for a single free block, which guarantees that there are no free blocks
|
|
// before this one. Also, whenever we free or shink a block we must check
|
|
// if this index needs adjusting (see gc_realloc and gc_free).
|
|
if (n_free == 1) {
|
|
#if MICROPY_GC_SPLIT_HEAP
|
|
MP_STATE_MEM(gc_last_free_area) = area;
|
|
#endif
|
|
area->gc_last_free_atb_index = (i + 1) / BLOCKS_PER_ATB;
|
|
}
|
|
|
|
area->gc_last_used_block = MAX(area->gc_last_used_block, end_block);
|
|
|
|
// mark first block as used head
|
|
ATB_FREE_TO_HEAD(area, start_block);
|
|
|
|
// mark rest of blocks as used tail
|
|
// TODO for a run of many blocks can make this more efficient
|
|
for (size_t bl = start_block + 1; bl <= end_block; bl++) {
|
|
ATB_FREE_TO_TAIL(area, bl);
|
|
}
|
|
|
|
// get pointer to first block
|
|
// we must create this pointer before unlocking the GC so a collection can find it
|
|
void *ret_ptr = (void *)(area->gc_pool_start + start_block * BYTES_PER_BLOCK);
|
|
DEBUG_printf("gc_alloc(%p)\n", ret_ptr);
|
|
|
|
#if MICROPY_GC_ALLOC_THRESHOLD
|
|
MP_STATE_MEM(gc_alloc_amount) += n_blocks;
|
|
#endif
|
|
|
|
GC_EXIT();
|
|
|
|
#if MICROPY_GC_CONSERVATIVE_CLEAR
|
|
// be conservative and zero out all the newly allocated blocks
|
|
memset((byte *)ret_ptr, 0, (end_block - start_block + 1) * BYTES_PER_BLOCK);
|
|
#else
|
|
// zero out the additional bytes of the newly allocated blocks
|
|
// This is needed because the blocks may have previously held pointers
|
|
// to the heap and will not be set to something else if the caller
|
|
// doesn't actually use the entire block. As such they will continue
|
|
// to point to the heap and may prevent other blocks from being reclaimed.
|
|
memset((byte *)ret_ptr + n_bytes, 0, (end_block - start_block + 1) * BYTES_PER_BLOCK - n_bytes);
|
|
#endif
|
|
|
|
#if MICROPY_ENABLE_FINALISER
|
|
if (has_finaliser) {
|
|
// clear type pointer in case it is never set
|
|
((mp_obj_base_t *)ret_ptr)->type = NULL;
|
|
// set mp_obj flag only if it has a finaliser
|
|
GC_ENTER();
|
|
FTB_SET(area, start_block);
|
|
GC_EXIT();
|
|
}
|
|
#else
|
|
(void)has_finaliser;
|
|
#endif
|
|
|
|
#if EXTENSIVE_HEAP_PROFILING
|
|
gc_dump_alloc_table(&mp_plat_print);
|
|
#endif
|
|
|
|
return ret_ptr;
|
|
}
|
|
|
|
/*
|
|
void *gc_alloc(mp_uint_t n_bytes) {
|
|
return _gc_alloc(n_bytes, false);
|
|
}
|
|
|
|
void *gc_alloc_with_finaliser(mp_uint_t n_bytes) {
|
|
return _gc_alloc(n_bytes, true);
|
|
}
|
|
*/
|
|
|
|
// force the freeing of a piece of memory
|
|
// TODO: freeing here does not call finaliser
|
|
void gc_free(void *ptr) {
|
|
if (MP_STATE_THREAD(gc_lock_depth) > 0) {
|
|
// Cannot free while the GC is locked. However free is an optimisation
|
|
// to reclaim the memory immediately, this means it will now be left
|
|
// until the next collection.
|
|
return;
|
|
}
|
|
|
|
GC_ENTER();
|
|
|
|
DEBUG_printf("gc_free(%p)\n", ptr);
|
|
|
|
if (ptr == NULL) {
|
|
// free(NULL) is a no-op
|
|
GC_EXIT();
|
|
return;
|
|
}
|
|
|
|
// get the GC block number corresponding to this pointer
|
|
mp_state_mem_area_t *area;
|
|
#if MICROPY_GC_SPLIT_HEAP
|
|
area = gc_get_ptr_area(ptr);
|
|
assert(area);
|
|
#else
|
|
assert(VERIFY_PTR(ptr));
|
|
area = &MP_STATE_MEM(area);
|
|
#endif
|
|
|
|
size_t block = BLOCK_FROM_PTR(area, ptr);
|
|
assert(ATB_GET_KIND(area, block) == AT_HEAD);
|
|
|
|
#if MICROPY_ENABLE_FINALISER
|
|
FTB_CLEAR(area, block);
|
|
#endif
|
|
|
|
#if MICROPY_GC_SPLIT_HEAP
|
|
if (MP_STATE_MEM(gc_last_free_area) != area) {
|
|
// We freed something but it isn't the current area. Reset the
|
|
// last free area to the start for a rescan. Note that this won't
|
|
// give much of a performance hit, since areas that are completely
|
|
// filled will likely be skipped (the gc_last_free_atb_index
|
|
// points to the last block).
|
|
// The reason why this is necessary is because it is not possible
|
|
// to see which area came first (like it is possible to adjust
|
|
// gc_last_free_atb_index based on whether the freed block is
|
|
// before the last free block).
|
|
MP_STATE_MEM(gc_last_free_area) = &MP_STATE_MEM(area);
|
|
}
|
|
#endif
|
|
|
|
// set the last_free pointer to this block if it's earlier in the heap
|
|
if (block / BLOCKS_PER_ATB < area->gc_last_free_atb_index) {
|
|
area->gc_last_free_atb_index = block / BLOCKS_PER_ATB;
|
|
}
|
|
|
|
// free head and all of its tail blocks
|
|
do {
|
|
ATB_ANY_TO_FREE(area, block);
|
|
block += 1;
|
|
} while (ATB_GET_KIND(area, block) == AT_TAIL);
|
|
|
|
GC_EXIT();
|
|
|
|
#if EXTENSIVE_HEAP_PROFILING
|
|
gc_dump_alloc_table(&mp_plat_print);
|
|
#endif
|
|
}
|
|
|
|
size_t gc_nbytes(const void *ptr) {
|
|
GC_ENTER();
|
|
|
|
mp_state_mem_area_t *area;
|
|
#if MICROPY_GC_SPLIT_HEAP
|
|
area = gc_get_ptr_area(ptr);
|
|
#else
|
|
if (VERIFY_PTR(ptr)) {
|
|
area = &MP_STATE_MEM(area);
|
|
} else {
|
|
area = NULL;
|
|
}
|
|
#endif
|
|
|
|
if (area) {
|
|
size_t block = BLOCK_FROM_PTR(area, ptr);
|
|
if (ATB_GET_KIND(area, block) == AT_HEAD) {
|
|
// work out number of consecutive blocks in the chain starting with this on
|
|
size_t n_blocks = 0;
|
|
do {
|
|
n_blocks += 1;
|
|
} while (ATB_GET_KIND(area, block + n_blocks) == AT_TAIL);
|
|
GC_EXIT();
|
|
return n_blocks * BYTES_PER_BLOCK;
|
|
}
|
|
}
|
|
|
|
// invalid pointer
|
|
GC_EXIT();
|
|
return 0;
|
|
}
|
|
|
|
#if 0
|
|
// old, simple realloc that didn't expand memory in place
|
|
void *gc_realloc(void *ptr, mp_uint_t n_bytes) {
|
|
mp_uint_t n_existing = gc_nbytes(ptr);
|
|
if (n_bytes <= n_existing) {
|
|
return ptr;
|
|
} else {
|
|
bool has_finaliser;
|
|
if (ptr == NULL) {
|
|
has_finaliser = false;
|
|
} else {
|
|
#if MICROPY_ENABLE_FINALISER
|
|
has_finaliser = FTB_GET(BLOCK_FROM_PTR((mp_uint_t)ptr));
|
|
#else
|
|
has_finaliser = false;
|
|
#endif
|
|
}
|
|
void *ptr2 = gc_alloc(n_bytes, has_finaliser);
|
|
if (ptr2 == NULL) {
|
|
return ptr2;
|
|
}
|
|
memcpy(ptr2, ptr, n_existing);
|
|
gc_free(ptr);
|
|
return ptr2;
|
|
}
|
|
}
|
|
|
|
#else // Alternative gc_realloc impl
|
|
|
|
void *gc_realloc(void *ptr_in, size_t n_bytes, bool allow_move) {
|
|
// check for pure allocation
|
|
if (ptr_in == NULL) {
|
|
return gc_alloc(n_bytes, false);
|
|
}
|
|
|
|
// check for pure free
|
|
if (n_bytes == 0) {
|
|
gc_free(ptr_in);
|
|
return NULL;
|
|
}
|
|
|
|
if (MP_STATE_THREAD(gc_lock_depth) > 0) {
|
|
return NULL;
|
|
}
|
|
|
|
void *ptr = ptr_in;
|
|
|
|
GC_ENTER();
|
|
|
|
// get the GC block number corresponding to this pointer
|
|
mp_state_mem_area_t *area;
|
|
#if MICROPY_GC_SPLIT_HEAP
|
|
area = gc_get_ptr_area(ptr);
|
|
assert(area);
|
|
#else
|
|
assert(VERIFY_PTR(ptr));
|
|
area = &MP_STATE_MEM(area);
|
|
#endif
|
|
size_t block = BLOCK_FROM_PTR(area, ptr);
|
|
assert(ATB_GET_KIND(area, block) == AT_HEAD);
|
|
|
|
// compute number of new blocks that are requested
|
|
size_t new_blocks = (n_bytes + BYTES_PER_BLOCK - 1) / BYTES_PER_BLOCK;
|
|
|
|
// Get the total number of consecutive blocks that are already allocated to
|
|
// this chunk of memory, and then count the number of free blocks following
|
|
// it. Stop if we reach the end of the heap, or if we find enough extra
|
|
// free blocks to satisfy the realloc. Note that we need to compute the
|
|
// total size of the existing memory chunk so we can correctly and
|
|
// efficiently shrink it (see below for shrinking code).
|
|
size_t n_free = 0;
|
|
size_t n_blocks = 1; // counting HEAD block
|
|
size_t max_block = area->gc_alloc_table_byte_len * BLOCKS_PER_ATB;
|
|
for (size_t bl = block + n_blocks; bl < max_block; bl++) {
|
|
byte block_type = ATB_GET_KIND(area, bl);
|
|
if (block_type == AT_TAIL) {
|
|
n_blocks++;
|
|
continue;
|
|
}
|
|
if (block_type == AT_FREE) {
|
|
n_free++;
|
|
if (n_blocks + n_free >= new_blocks) {
|
|
// stop as soon as we find enough blocks for n_bytes
|
|
break;
|
|
}
|
|
continue;
|
|
}
|
|
break;
|
|
}
|
|
|
|
// return original ptr if it already has the requested number of blocks
|
|
if (new_blocks == n_blocks) {
|
|
GC_EXIT();
|
|
return ptr_in;
|
|
}
|
|
|
|
// check if we can shrink the allocated area
|
|
if (new_blocks < n_blocks) {
|
|
// free unneeded tail blocks
|
|
for (size_t bl = block + new_blocks, count = n_blocks - new_blocks; count > 0; bl++, count--) {
|
|
ATB_ANY_TO_FREE(area, bl);
|
|
}
|
|
|
|
#if MICROPY_GC_SPLIT_HEAP
|
|
if (MP_STATE_MEM(gc_last_free_area) != area) {
|
|
// See comment in gc_free.
|
|
MP_STATE_MEM(gc_last_free_area) = &MP_STATE_MEM(area);
|
|
}
|
|
#endif
|
|
|
|
// set the last_free pointer to end of this block if it's earlier in the heap
|
|
if ((block + new_blocks) / BLOCKS_PER_ATB < area->gc_last_free_atb_index) {
|
|
area->gc_last_free_atb_index = (block + new_blocks) / BLOCKS_PER_ATB;
|
|
}
|
|
|
|
GC_EXIT();
|
|
|
|
#if EXTENSIVE_HEAP_PROFILING
|
|
gc_dump_alloc_table(&mp_plat_print);
|
|
#endif
|
|
|
|
return ptr_in;
|
|
}
|
|
|
|
// check if we can expand in place
|
|
if (new_blocks <= n_blocks + n_free) {
|
|
// mark few more blocks as used tail
|
|
size_t end_block = block + new_blocks;
|
|
for (size_t bl = block + n_blocks; bl < end_block; bl++) {
|
|
assert(ATB_GET_KIND(area, bl) == AT_FREE);
|
|
ATB_FREE_TO_TAIL(area, bl);
|
|
}
|
|
|
|
area->gc_last_used_block = MAX(area->gc_last_used_block, end_block);
|
|
|
|
GC_EXIT();
|
|
|
|
#if MICROPY_GC_CONSERVATIVE_CLEAR
|
|
// be conservative and zero out all the newly allocated blocks
|
|
memset((byte *)ptr_in + n_blocks * BYTES_PER_BLOCK, 0, (new_blocks - n_blocks) * BYTES_PER_BLOCK);
|
|
#else
|
|
// zero out the additional bytes of the newly allocated blocks (see comment above in gc_alloc)
|
|
memset((byte *)ptr_in + n_bytes, 0, new_blocks * BYTES_PER_BLOCK - n_bytes);
|
|
#endif
|
|
|
|
#if EXTENSIVE_HEAP_PROFILING
|
|
gc_dump_alloc_table(&mp_plat_print);
|
|
#endif
|
|
|
|
return ptr_in;
|
|
}
|
|
|
|
#if MICROPY_ENABLE_FINALISER
|
|
bool ftb_state = FTB_GET(area, block);
|
|
#else
|
|
bool ftb_state = false;
|
|
#endif
|
|
|
|
GC_EXIT();
|
|
|
|
if (!allow_move) {
|
|
// not allowed to move memory block so return failure
|
|
return NULL;
|
|
}
|
|
|
|
// can't resize inplace; try to find a new contiguous chain
|
|
void *ptr_out = gc_alloc(n_bytes, ftb_state);
|
|
|
|
// check that the alloc succeeded
|
|
if (ptr_out == NULL) {
|
|
return NULL;
|
|
}
|
|
|
|
DEBUG_printf("gc_realloc(%p -> %p)\n", ptr_in, ptr_out);
|
|
memcpy(ptr_out, ptr_in, n_blocks * BYTES_PER_BLOCK);
|
|
gc_free(ptr_in);
|
|
return ptr_out;
|
|
}
|
|
#endif // Alternative gc_realloc impl
|
|
|
|
void gc_dump_info(const mp_print_t *print) {
|
|
gc_info_t info;
|
|
gc_info(&info);
|
|
mp_printf(print, "GC: total: %u, used: %u, free: %u",
|
|
(uint)info.total, (uint)info.used, (uint)info.free);
|
|
#if MICROPY_GC_SPLIT_HEAP_AUTO
|
|
mp_printf(print, ", max new split: %u", (uint)info.max_new_split);
|
|
#endif
|
|
mp_printf(print, "\n No. of 1-blocks: %u, 2-blocks: %u, max blk sz: %u, max free sz: %u\n",
|
|
(uint)info.num_1block, (uint)info.num_2block, (uint)info.max_block, (uint)info.max_free);
|
|
}
|
|
|
|
void gc_dump_alloc_table(const mp_print_t *print) {
|
|
GC_ENTER();
|
|
static const size_t DUMP_BYTES_PER_LINE = 64;
|
|
for (mp_state_mem_area_t *area = &MP_STATE_MEM(area); area != NULL; area = NEXT_AREA(area)) {
|
|
#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(print, "GC memory layout; from %p:", area->gc_pool_start);
|
|
#endif
|
|
for (size_t bl = 0; bl < area->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 < area->gc_alloc_table_byte_len * BLOCKS_PER_ATB && ATB_GET_KIND(area, 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(print, "\n (%u lines all free)", (uint)(bl2 - bl) / DUMP_BYTES_PER_LINE);
|
|
bl = bl2 & (~(DUMP_BYTES_PER_LINE - 1));
|
|
if (bl >= area->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)
|
|
mp_printf(print, "\n%08x: ", (uint)(bl * BYTES_PER_BLOCK));
|
|
}
|
|
int c = ' ';
|
|
switch (ATB_GET_KIND(area, 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 (gc_get_ptr_area(ptr) && BLOCK_FROM_PTR(ptr) == bl) {
|
|
c = 'B';
|
|
break;
|
|
}
|
|
}
|
|
if (c == 'h') {
|
|
ptrs = (void**)&c;
|
|
len = ((mp_uint_t)MP_STATE_THREAD(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 (gc_get_ptr_area(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 **)(area->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';
|
|
} else if (*ptr == &mp_type_str || *ptr == &mp_type_bytes) {
|
|
c = 'S';
|
|
}
|
|
#if MICROPY_PY_BUILTINS_BYTEARRAY
|
|
else if (*ptr == &mp_type_bytearray) {
|
|
c = 'A';
|
|
}
|
|
#endif
|
|
#if MICROPY_PY_ARRAY
|
|
else if (*ptr == &mp_type_array) {
|
|
c = 'A';
|
|
}
|
|
#endif
|
|
#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 = '=';
|
|
break;
|
|
case AT_MARK:
|
|
c = 'm';
|
|
break;
|
|
}
|
|
mp_printf(print, "%c", c);
|
|
}
|
|
mp_print_str(print, "\n");
|
|
}
|
|
GC_EXIT();
|
|
}
|
|
|
|
#if 0
|
|
// For testing the GC functions
|
|
void gc_test(void) {
|
|
mp_uint_t len = 500;
|
|
mp_uint_t *heap = malloc(len);
|
|
gc_init(heap, heap + len / sizeof(mp_uint_t));
|
|
void *ptrs[100];
|
|
{
|
|
mp_uint_t **p = gc_alloc(16, false);
|
|
p[0] = gc_alloc(64, false);
|
|
p[1] = gc_alloc(1, false);
|
|
p[2] = gc_alloc(1, false);
|
|
p[3] = gc_alloc(1, false);
|
|
mp_uint_t ***p2 = gc_alloc(16, false);
|
|
p2[0] = p;
|
|
p2[1] = p;
|
|
ptrs[0] = p2;
|
|
}
|
|
for (int i = 0; i < 25; i += 2) {
|
|
mp_uint_t *p = gc_alloc(i, false);
|
|
printf("p=%p\n", p);
|
|
if (i & 3) {
|
|
// ptrs[i] = p;
|
|
}
|
|
}
|
|
|
|
printf("Before GC:\n");
|
|
gc_dump_alloc_table(&mp_plat_print);
|
|
printf("Starting GC...\n");
|
|
gc_collect_start();
|
|
gc_collect_root(ptrs, sizeof(ptrs) / sizeof(void *));
|
|
gc_collect_end();
|
|
printf("After GC:\n");
|
|
gc_dump_alloc_table(&mp_plat_print);
|
|
}
|
|
#endif
|
|
|
|
#endif // MICROPY_ENABLE_GC
|