2467c61b3b
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
970 lines
26 KiB
C
970 lines
26 KiB
C
#include <stddef.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <linux/stringify.h>
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#include "tlsf.h"
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#include "tlsfbits.h"
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#ifdef DEBUG
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#define tlsf_assert(expr) \
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((expr) ? (void)(0) : printf("%s\n", __stringify(expr)))
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#else
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#define tlsf_assert(expr) (void)(0)
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#endif
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/*
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** Constants.
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*/
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/* Public constants: may be modified. */
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enum tlsf_public
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{
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/* log2 of number of linear subdivisions of block sizes. */
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SL_INDEX_COUNT_LOG2 = 5,
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};
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/* Private constants: do not modify. */
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enum tlsf_private
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{
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#if defined (TLSF_64BIT)
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/* All allocation sizes and addresses are aligned to 8 bytes. */
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ALIGN_SIZE_LOG2 = 3,
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#else
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/* All allocation sizes and addresses are aligned to 4 bytes. */
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ALIGN_SIZE_LOG2 = 2,
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#endif
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ALIGN_SIZE = (1 << ALIGN_SIZE_LOG2),
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/*
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** We support allocations of sizes up to (1 << FL_INDEX_MAX) bits.
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** However, because we linearly subdivide the second-level lists, and
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** our minimum size granularity is 4 bytes, it doesn't make sense to
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** create first-level lists for sizes smaller than SL_INDEX_COUNT * 4,
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** or (1 << (SL_INDEX_COUNT_LOG2 + 2)) bytes, as there we will be
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** trying to split size ranges into more slots than we have available.
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** Instead, we calculate the minimum threshold size, and place all
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** blocks below that size into the 0th first-level list.
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*/
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#if defined (TLSF_64BIT)
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/*
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** TODO: We can increase this to support larger sizes, at the expense
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** of more overhead in the TLSF structure.
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*/
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FL_INDEX_MAX = 32,
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#else
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FL_INDEX_MAX = 30,
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#endif
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SL_INDEX_COUNT = (1 << SL_INDEX_COUNT_LOG2),
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FL_INDEX_SHIFT = (SL_INDEX_COUNT_LOG2 + ALIGN_SIZE_LOG2),
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FL_INDEX_COUNT = (FL_INDEX_MAX - FL_INDEX_SHIFT + 1),
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SMALL_BLOCK_SIZE = (1 << FL_INDEX_SHIFT),
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};
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/*
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** Cast and min/max macros.
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*/
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#define tlsf_cast(t, exp) ((t) (exp))
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#define tlsf_min(a, b) ((a) < (b) ? (a) : (b))
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#define tlsf_max(a, b) ((a) > (b) ? (a) : (b))
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/*
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** Set assert macro, if it has not been provided by the user.
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*/
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#if !defined (tlsf_assert)
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#define tlsf_assert assert
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#endif
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/*
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** Static assertion mechanism.
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*/
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#define _tlsf_glue2(x, y) x ## y
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#define _tlsf_glue(x, y) _tlsf_glue2(x, y)
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#define tlsf_static_assert(exp) \
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typedef char _tlsf_glue(static_assert, __LINE__) [(exp) ? 1 : -1]
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#ifndef __BAREBOX__
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/* This code has been tested on 32- and 64-bit (LP/LLP) architectures. */
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tlsf_static_assert(sizeof(int) * CHAR_BIT == 32);
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tlsf_static_assert(sizeof(size_t) * CHAR_BIT >= 32);
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tlsf_static_assert(sizeof(size_t) * CHAR_BIT <= 64);
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/* SL_INDEX_COUNT must be <= number of bits in sl_bitmap's storage type. */
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tlsf_static_assert(sizeof(unsigned int) * CHAR_BIT >= SL_INDEX_COUNT);
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/* Ensure we've properly tuned our sizes. */
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tlsf_static_assert(ALIGN_SIZE == SMALL_BLOCK_SIZE / SL_INDEX_COUNT);
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#endif
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/*
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** Data structures and associated constants.
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*/
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/*
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** Block header structure.
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**
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** There are several implementation subtleties involved:
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** - The prev_phys_block field is only valid if the previous block is free.
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** - The prev_phys_block field is actually stored at the end of the
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** previous block. It appears at the beginning of this structure only to
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** simplify the implementation.
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** - The next_free / prev_free fields are only valid if the block is free.
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*/
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typedef struct block_header_t
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{
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/* Points to the previous physical block. */
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struct block_header_t* prev_phys_block;
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/* The size of this block, excluding the block header. */
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size_t size;
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/* Next and previous free blocks. */
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struct block_header_t* next_free;
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struct block_header_t* prev_free;
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} block_header_t;
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/*
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** Since block sizes are always at least a multiple of 4, the two least
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** significant bits of the size field are used to store the block status:
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** - bit 0: whether block is busy or free
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** - bit 1: whether previous block is busy or free
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*/
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static const size_t block_header_free_bit = 1 << 0;
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static const size_t block_header_prev_free_bit = 1 << 1;
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/*
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** The size of the block header exposed to used blocks is the size field.
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** The prev_phys_block field is stored *inside* the previous free block.
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*/
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static const size_t block_header_overhead = sizeof(size_t);
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/* User data starts directly after the size field in a used block. */
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static const size_t block_start_offset =
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offsetof(block_header_t, size) + sizeof(size_t);
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/*
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** A free block must be large enough to store its header minus the size of
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** the prev_phys_block field, and no larger than the number of addressable
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** bits for FL_INDEX.
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*/
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static const size_t block_size_min =
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sizeof(block_header_t) - sizeof(block_header_t*);
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static const size_t block_size_max = tlsf_cast(size_t, 1) << FL_INDEX_MAX;
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/* The TLSF pool structure. */
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typedef struct pool_t
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{
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/* Empty lists point at this block to indicate they are free. */
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block_header_t block_null;
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/* Bitmaps for free lists. */
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unsigned int fl_bitmap;
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unsigned int sl_bitmap[FL_INDEX_COUNT];
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/* Head of free lists. */
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block_header_t* blocks[FL_INDEX_COUNT][SL_INDEX_COUNT];
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} pool_t;
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/* A type used for casting when doing pointer arithmetic. */
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typedef ptrdiff_t tlsfptr_t;
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/*
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** block_header_t member functions.
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*/
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static size_t block_size(const block_header_t* block)
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{
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return block->size & ~(block_header_free_bit | block_header_prev_free_bit);
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}
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static void block_set_size(block_header_t* block, size_t size)
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{
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const size_t oldsize = block->size;
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block->size = size | (oldsize & (block_header_free_bit | block_header_prev_free_bit));
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}
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static int block_is_last(const block_header_t* block)
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{
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return 0 == block_size(block);
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}
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static int block_is_free(const block_header_t* block)
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{
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return tlsf_cast(int, block->size & block_header_free_bit);
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}
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static void block_set_free(block_header_t* block)
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{
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block->size |= block_header_free_bit;
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}
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static void block_set_used(block_header_t* block)
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{
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block->size &= ~block_header_free_bit;
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}
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static int block_is_prev_free(const block_header_t* block)
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{
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return tlsf_cast(int, block->size & block_header_prev_free_bit);
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}
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static void block_set_prev_free(block_header_t* block)
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{
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block->size |= block_header_prev_free_bit;
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}
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static void block_set_prev_used(block_header_t* block)
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{
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block->size &= ~block_header_prev_free_bit;
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}
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static block_header_t* block_from_ptr(const void* ptr)
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{
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return tlsf_cast(block_header_t*,
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tlsf_cast(unsigned char*, ptr) - block_start_offset);
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}
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static void* block_to_ptr(const block_header_t* block)
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{
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return tlsf_cast(void*,
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tlsf_cast(unsigned char*, block) + block_start_offset);
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}
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/* Return location of next block after block of given size. */
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static block_header_t* offset_to_block(const void* ptr, size_t size)
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{
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return tlsf_cast(block_header_t*, tlsf_cast(tlsfptr_t, ptr) + size);
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}
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/* Return location of previous block. */
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static block_header_t* block_prev(const block_header_t* block)
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{
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return block->prev_phys_block;
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}
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/* Return location of next existing block. */
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static block_header_t* block_next(const block_header_t* block)
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{
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block_header_t* next = offset_to_block(block_to_ptr(block),
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block_size(block) - block_header_overhead);
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tlsf_assert(!block_is_last(block));
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return next;
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}
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/* Link a new block with its physical neighbor, return the neighbor. */
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static block_header_t* block_link_next(block_header_t* block)
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{
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block_header_t* next = block_next(block);
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next->prev_phys_block = block;
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return next;
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}
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static void block_mark_as_free(block_header_t* block)
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{
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/* Link the block to the next block, first. */
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block_header_t* next = block_link_next(block);
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block_set_prev_free(next);
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block_set_free(block);
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}
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static void block_mark_as_used(block_header_t* block)
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{
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block_header_t* next = block_next(block);
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block_set_prev_used(next);
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block_set_used(block);
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}
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static size_t align_up(size_t x, size_t align)
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{
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tlsf_assert(0 == (align & (align - 1)) && "must align to a power of two");
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return (x + (align - 1)) & ~(align - 1);
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}
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static size_t align_down(size_t x, size_t align)
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{
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tlsf_assert(0 == (align & (align - 1)) && "must align to a power of two");
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return x - (x & (align - 1));
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}
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static void* align_ptr(const void* ptr, size_t align)
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{
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const tlsfptr_t aligned =
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(tlsf_cast(tlsfptr_t, ptr) + (align - 1)) & ~(align - 1);
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tlsf_assert(0 == (align & (align - 1)) && "must align to a power of two");
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return tlsf_cast(void*, aligned);
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}
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/*
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** Adjust an allocation size to be aligned to word size, and no smaller
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** than internal minimum.
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*/
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static size_t adjust_request_size(size_t size, size_t align)
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{
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size_t adjust = 0;
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if (size && size < block_size_max)
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{
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const size_t aligned = align_up(size, align);
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adjust = tlsf_max(aligned, block_size_min);
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}
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return adjust;
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}
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/*
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** TLSF utility functions. In most cases, these are direct translations of
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** the documentation found in the white paper.
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*/
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static void mapping_insert(size_t size, int* fli, int* sli)
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{
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int fl, sl;
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if (size < SMALL_BLOCK_SIZE)
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{
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/* Store small blocks in first list. */
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fl = 0;
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sl = tlsf_cast(int, size) / (SMALL_BLOCK_SIZE / SL_INDEX_COUNT);
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}
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else
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{
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fl = tlsf_fls_sizet(size);
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sl = tlsf_cast(int, size >> (fl - SL_INDEX_COUNT_LOG2)) ^ (1 << SL_INDEX_COUNT_LOG2);
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fl -= (FL_INDEX_SHIFT - 1);
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}
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*fli = fl;
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*sli = sl;
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}
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/* This version rounds up to the next block size (for allocations) */
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static void mapping_search(size_t size, int* fli, int* sli)
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{
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if (size >= (1 << SL_INDEX_COUNT_LOG2))
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{
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const size_t round = (1 << (tlsf_fls_sizet(size) - SL_INDEX_COUNT_LOG2)) - 1;
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size += round;
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}
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mapping_insert(size, fli, sli);
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}
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static block_header_t* search_suitable_block(pool_t* pool, int* fli, int* sli)
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{
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int fl = *fli;
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int sl = *sli;
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/*
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** First, search for a block in the list associated with the given
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** fl/sl index.
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*/
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unsigned int sl_map = pool->sl_bitmap[fl] & (~0 << sl);
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if (!sl_map)
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{
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/* No block exists. Search in the next largest first-level list. */
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const unsigned int fl_map = pool->fl_bitmap & (~0 << (fl + 1));
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if (!fl_map)
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{
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/* No free blocks available, memory has been exhausted. */
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return 0;
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}
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fl = tlsf_ffs(fl_map);
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*fli = fl;
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sl_map = pool->sl_bitmap[fl];
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}
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tlsf_assert(sl_map && "internal error - second level bitmap is null");
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sl = tlsf_ffs(sl_map);
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*sli = sl;
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/* Return the first block in the free list. */
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return pool->blocks[fl][sl];
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}
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/* Remove a free block from the free list.*/
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static void remove_free_block(pool_t* pool, block_header_t* block, int fl, int sl)
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{
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block_header_t* prev = block->prev_free;
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block_header_t* next = block->next_free;
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tlsf_assert(prev && "prev_free field can not be null");
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tlsf_assert(next && "next_free field can not be null");
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next->prev_free = prev;
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prev->next_free = next;
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/* If this block is the head of the free list, set new head. */
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if (pool->blocks[fl][sl] == block)
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{
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pool->blocks[fl][sl] = next;
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/* If the new head is null, clear the bitmap. */
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if (next == &pool->block_null)
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{
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pool->sl_bitmap[fl] &= ~(1 << sl);
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/* If the second bitmap is now empty, clear the fl bitmap. */
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if (!pool->sl_bitmap[fl])
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{
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pool->fl_bitmap &= ~(1 << fl);
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}
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}
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}
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}
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/* Insert a free block into the free block list. */
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static void insert_free_block(pool_t* pool, block_header_t* block, int fl, int sl)
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{
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block_header_t* current = pool->blocks[fl][sl];
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tlsf_assert(current && "free list cannot have a null entry");
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tlsf_assert(block && "cannot insert a null entry into the free list");
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block->next_free = current;
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block->prev_free = &pool->block_null;
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current->prev_free = block;
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tlsf_assert(block_to_ptr(block) == align_ptr(block_to_ptr(block), ALIGN_SIZE)
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&& "block not aligned properly");
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/*
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** Insert the new block at the head of the list, and mark the first-
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** and second-level bitmaps appropriately.
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*/
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pool->blocks[fl][sl] = block;
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pool->fl_bitmap |= (1 << fl);
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pool->sl_bitmap[fl] |= (1 << sl);
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}
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/* Remove a given block from the free list. */
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static void block_remove(pool_t* pool, block_header_t* block)
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{
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int fl, sl;
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mapping_insert(block_size(block), &fl, &sl);
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remove_free_block(pool, block, fl, sl);
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}
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/* Insert a given block into the free list. */
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static void block_insert(pool_t* pool, block_header_t* block)
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{
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int fl, sl;
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mapping_insert(block_size(block), &fl, &sl);
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insert_free_block(pool, block, fl, sl);
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}
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static int block_can_split(block_header_t* block, size_t size)
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{
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return block_size(block) >= sizeof(block_header_t) + size;
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}
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/* Split a block into two, the second of which is free. */
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static block_header_t* block_split(block_header_t* block, size_t size)
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{
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/* Calculate the amount of space left in the remaining block. */
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block_header_t* remaining =
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offset_to_block(block_to_ptr(block), size - block_header_overhead);
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const size_t remain_size = block_size(block) - (size + block_header_overhead);
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tlsf_assert(block_to_ptr(remaining) == align_ptr(block_to_ptr(remaining), ALIGN_SIZE)
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&& "remaining block not aligned properly");
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tlsf_assert(block_size(block) == remain_size + size + block_header_overhead);
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block_set_size(remaining, remain_size);
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tlsf_assert(block_size(remaining) >= block_size_min && "block split with invalid size");
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block_set_size(block, size);
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block_mark_as_free(remaining);
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return remaining;
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}
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/* Absorb a free block's storage into an adjacent previous free block. */
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static block_header_t* block_absorb(block_header_t* prev, block_header_t* block)
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{
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tlsf_assert(!block_is_last(prev) && "previous block can't be last!");
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/* Note: Leaves flags untouched. */
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prev->size += block_size(block) + block_header_overhead;
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block_link_next(prev);
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return prev;
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}
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/* Merge a just-freed block with an adjacent previous free block. */
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static block_header_t* block_merge_prev(pool_t* pool, block_header_t* block)
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{
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if (block_is_prev_free(block))
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{
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block_header_t* prev = block_prev(block);
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tlsf_assert(prev && "prev physical block can't be null");
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tlsf_assert(block_is_free(prev) && "prev block is not free though marked as such");
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block_remove(pool, prev);
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block = block_absorb(prev, block);
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}
|
|
|
|
return block;
|
|
}
|
|
|
|
/* Merge a just-freed block with an adjacent free block. */
|
|
static block_header_t* block_merge_next(pool_t* pool, block_header_t* block)
|
|
{
|
|
block_header_t* next = block_next(block);
|
|
tlsf_assert(next && "next physical block can't be null");
|
|
|
|
if (block_is_free(next))
|
|
{
|
|
tlsf_assert(!block_is_last(block) && "previous block can't be last!");
|
|
block_remove(pool, next);
|
|
block = block_absorb(block, next);
|
|
}
|
|
|
|
return block;
|
|
}
|
|
|
|
/* Trim any trailing block space off the end of a block, return to pool. */
|
|
static void block_trim_free(pool_t* pool, block_header_t* block, size_t size)
|
|
{
|
|
tlsf_assert(block_is_free(block) && "block must be free");
|
|
if (block_can_split(block, size))
|
|
{
|
|
block_header_t* remaining_block = block_split(block, size);
|
|
block_link_next(block);
|
|
block_set_prev_free(remaining_block);
|
|
block_insert(pool, remaining_block);
|
|
}
|
|
}
|
|
|
|
/* Trim any trailing block space off the end of a used block, return to pool. */
|
|
static void block_trim_used(pool_t* pool, block_header_t* block, size_t size)
|
|
{
|
|
tlsf_assert(!block_is_free(block) && "block must be used");
|
|
if (block_can_split(block, size))
|
|
{
|
|
/* If the next block is free, we must coalesce. */
|
|
block_header_t* remaining_block = block_split(block, size);
|
|
block_set_prev_used(remaining_block);
|
|
|
|
remaining_block = block_merge_next(pool, remaining_block);
|
|
block_insert(pool, remaining_block);
|
|
}
|
|
}
|
|
|
|
static block_header_t* block_trim_free_leading(pool_t* pool, block_header_t* block, size_t size)
|
|
{
|
|
block_header_t* remaining_block = block;
|
|
if (block_can_split(block, size))
|
|
{
|
|
/* We want the 2nd block. */
|
|
remaining_block = block_split(block, size - block_header_overhead);
|
|
block_set_prev_free(remaining_block);
|
|
|
|
block_link_next(block);
|
|
block_insert(pool, block);
|
|
}
|
|
|
|
return remaining_block;
|
|
}
|
|
|
|
static block_header_t* block_locate_free(pool_t* pool, size_t size)
|
|
{
|
|
int fl = 0, sl = 0;
|
|
block_header_t* block = 0;
|
|
|
|
if (size)
|
|
{
|
|
mapping_search(size, &fl, &sl);
|
|
block = search_suitable_block(pool, &fl, &sl);
|
|
}
|
|
|
|
if (block)
|
|
{
|
|
tlsf_assert(block_size(block) >= size);
|
|
remove_free_block(pool, block, fl, sl);
|
|
}
|
|
|
|
return block;
|
|
}
|
|
|
|
static void* block_prepare_used(pool_t* pool, block_header_t* block, size_t size)
|
|
{
|
|
void* p = 0;
|
|
if (block)
|
|
{
|
|
block_trim_free(pool, block, size);
|
|
block_mark_as_used(block);
|
|
p = block_to_ptr(block);
|
|
}
|
|
return p;
|
|
}
|
|
|
|
/* Clear structure and point all empty lists at the null block. */
|
|
static void pool_construct(pool_t* pool)
|
|
{
|
|
int i, j;
|
|
|
|
pool->block_null.next_free = &pool->block_null;
|
|
pool->block_null.prev_free = &pool->block_null;
|
|
|
|
pool->fl_bitmap = 0;
|
|
for (i = 0; i < FL_INDEX_COUNT; ++i)
|
|
{
|
|
pool->sl_bitmap[i] = 0;
|
|
for (j = 0; j < SL_INDEX_COUNT; ++j)
|
|
{
|
|
pool->blocks[i][j] = &pool->block_null;
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
** Debugging utilities.
|
|
*/
|
|
|
|
typedef struct integrity_t
|
|
{
|
|
int prev_status;
|
|
int status;
|
|
} integrity_t;
|
|
|
|
#define tlsf_insist(x) { tlsf_assert(x); if (!(x)) { status--; } }
|
|
|
|
static void integrity_walker(void* ptr, size_t size, int used, void* user)
|
|
{
|
|
block_header_t* block = block_from_ptr(ptr);
|
|
integrity_t* integ = tlsf_cast(integrity_t*, user);
|
|
const int this_prev_status = block_is_prev_free(block) ? 1 : 0;
|
|
const int this_status = block_is_free(block) ? 1 : 0;
|
|
const size_t this_block_size = block_size(block);
|
|
|
|
int status = 0;
|
|
tlsf_insist(integ->prev_status == this_prev_status && "prev status incorrect");
|
|
tlsf_insist(size == this_block_size && "block size incorrect");
|
|
|
|
integ->prev_status = this_status;
|
|
integ->status += status;
|
|
}
|
|
|
|
int tlsf_check_heap(tlsf_pool tlsf)
|
|
{
|
|
int i, j;
|
|
|
|
pool_t* pool = tlsf_cast(pool_t*, tlsf);
|
|
int status = 0;
|
|
|
|
/* Check that the blocks are physically correct. */
|
|
integrity_t integ = { 0, 0 };
|
|
tlsf_walk_heap(tlsf, integrity_walker, &integ);
|
|
status = integ.status;
|
|
|
|
/* Check that the free lists and bitmaps are accurate. */
|
|
for (i = 0; i < FL_INDEX_COUNT; ++i)
|
|
{
|
|
for (j = 0; j < SL_INDEX_COUNT; ++j)
|
|
{
|
|
const int fl_map = pool->fl_bitmap & (1 << i);
|
|
const int sl_list = pool->sl_bitmap[i];
|
|
const int sl_map = sl_list & (1 << j);
|
|
const block_header_t* block = pool->blocks[i][j];
|
|
|
|
/* Check that first- and second-level lists agree. */
|
|
if (!fl_map)
|
|
{
|
|
tlsf_insist(!sl_map && "second-level map must be null");
|
|
}
|
|
|
|
if (!sl_map)
|
|
{
|
|
tlsf_insist(block == &pool->block_null && "block list must be null");
|
|
continue;
|
|
}
|
|
|
|
/* Check that there is at least one free block. */
|
|
tlsf_insist(sl_list && "no free blocks in second-level map");
|
|
tlsf_insist(block != &pool->block_null && "block should not be null");
|
|
|
|
while (block != &pool->block_null)
|
|
{
|
|
int fli, sli;
|
|
tlsf_insist(block_is_free(block) && "block should be free");
|
|
tlsf_insist(!block_is_prev_free(block) && "blocks should have coalesced");
|
|
tlsf_insist(!block_is_free(block_next(block)) && "blocks should have coalesced");
|
|
tlsf_insist(block_is_prev_free(block_next(block)) && "block should be free");
|
|
tlsf_insist(block_size(block) >= block_size_min && "block not minimum size");
|
|
|
|
mapping_insert(block_size(block), &fli, &sli);
|
|
tlsf_insist(fli == i && sli == j && "block size indexed in wrong list");
|
|
block = block->next_free;
|
|
}
|
|
}
|
|
}
|
|
|
|
return status;
|
|
}
|
|
|
|
#undef tlsf_insist
|
|
|
|
static void default_walker(void* ptr, size_t size, int used, void* user)
|
|
{
|
|
(void)user;
|
|
printf("\t%p %s size: %x (%p)\n", ptr, used ? "used" : "free", (unsigned int)size, block_from_ptr(ptr));
|
|
}
|
|
|
|
void tlsf_walk_heap(tlsf_pool pool, tlsf_walker walker, void* user)
|
|
{
|
|
tlsf_walker heap_walker = walker ? walker : default_walker;
|
|
block_header_t* block =
|
|
offset_to_block(pool, sizeof(pool_t) - block_header_overhead);
|
|
|
|
while (block && !block_is_last(block))
|
|
{
|
|
heap_walker(
|
|
block_to_ptr(block),
|
|
block_size(block),
|
|
!block_is_free(block),
|
|
user);
|
|
block = block_next(block);
|
|
}
|
|
}
|
|
|
|
size_t tlsf_block_size(void* ptr)
|
|
{
|
|
size_t size = 0;
|
|
if (ptr)
|
|
{
|
|
const block_header_t* block = block_from_ptr(ptr);
|
|
size = block_size(block);
|
|
}
|
|
return size;
|
|
}
|
|
|
|
/*
|
|
** Overhead of the TLSF structures in a given memory block passed to
|
|
** tlsf_create, equal to the size of a pool_t plus overhead of the initial
|
|
** free block and the sentinel block.
|
|
*/
|
|
size_t tlsf_overhead()
|
|
{
|
|
const size_t pool_overhead = sizeof(pool_t) + 2 * block_header_overhead;
|
|
return pool_overhead;
|
|
}
|
|
|
|
/*
|
|
** TLSF main interface. Right out of the white paper.
|
|
*/
|
|
|
|
tlsf_pool tlsf_create(void* mem, size_t bytes)
|
|
{
|
|
block_header_t* block;
|
|
block_header_t* next;
|
|
|
|
const size_t pool_overhead = tlsf_overhead();
|
|
const size_t pool_bytes = align_down(bytes - pool_overhead, ALIGN_SIZE);
|
|
pool_t* pool = tlsf_cast(pool_t*, mem);
|
|
|
|
#ifdef DEBUG
|
|
/* Verify ffs/fls work properly. */
|
|
int rv = 0;
|
|
rv += (tlsf_ffs(0) == -1) ? 0 : 0x1;
|
|
rv += (tlsf_fls(0) == -1) ? 0 : 0x2;
|
|
rv += (tlsf_ffs(1) == 0) ? 0 : 0x4;
|
|
rv += (tlsf_fls(1) == 0) ? 0 : 0x8;
|
|
rv += (tlsf_ffs(0x80000000) == 31) ? 0 : 0x10;
|
|
rv += (tlsf_ffs(0x80008000) == 15) ? 0 : 0x20;
|
|
rv += (tlsf_fls(0x80000008) == 31) ? 0 : 0x40;
|
|
rv += (tlsf_fls(0x7FFFFFFF) == 30) ? 0 : 0x80;
|
|
|
|
#if defined (TLSF_64BIT)
|
|
rv += (tlsf_fls_sizet(0x80000000) == 31) ? 0 : 0x100;
|
|
rv += (tlsf_fls_sizet(0x100000000) == 32) ? 0 : 0x200;
|
|
rv += (tlsf_fls_sizet(0xffffffffffffffff) == 63) ? 0 : 0x400;
|
|
if (rv)
|
|
{
|
|
printf("tlsf_create: %x ffs/fls tests failed!\n", rv);
|
|
return 0;
|
|
}
|
|
#endif
|
|
#endif
|
|
|
|
if (pool_bytes < block_size_min || pool_bytes > block_size_max)
|
|
{
|
|
#if defined (TLSF_64BIT)
|
|
printf("tlsf_create: Pool size must be at least %d bytes.\n",
|
|
(unsigned int)(pool_overhead + block_size_min));
|
|
#else
|
|
printf("tlsf_create: Pool size must be between %u and %u bytes.\n",
|
|
(unsigned int)(pool_overhead + block_size_min),
|
|
(unsigned int)(pool_overhead + block_size_max));
|
|
#endif
|
|
return 0;
|
|
}
|
|
|
|
/* Construct a valid pool object. */
|
|
pool_construct(pool);
|
|
|
|
/*
|
|
** Create the main free block. Offset the start of the block slightly
|
|
** so that the prev_phys_block field falls inside of the pool
|
|
** structure - it will never be used.
|
|
*/
|
|
block = offset_to_block(
|
|
tlsf_cast(void*, pool), sizeof(pool_t) - block_header_overhead);
|
|
block_set_size(block, pool_bytes);
|
|
block_set_free(block);
|
|
block_set_prev_used(block);
|
|
block_insert(pool, block);
|
|
|
|
/* Split the block to create a zero-size pool sentinel block. */
|
|
next = block_link_next(block);
|
|
block_set_size(next, 0);
|
|
block_set_used(next);
|
|
block_set_prev_free(next);
|
|
|
|
return tlsf_cast(tlsf_pool, pool);
|
|
}
|
|
|
|
void tlsf_destroy(tlsf_pool pool)
|
|
{
|
|
/* Nothing to do. */
|
|
pool = pool;
|
|
}
|
|
|
|
void* tlsf_malloc(tlsf_pool tlsf, size_t size)
|
|
{
|
|
pool_t* pool = tlsf_cast(pool_t*, tlsf);
|
|
const size_t adjust = adjust_request_size(size, ALIGN_SIZE);
|
|
block_header_t* block = block_locate_free(pool, adjust);
|
|
return block_prepare_used(pool, block, adjust);
|
|
}
|
|
|
|
void* tlsf_memalign(tlsf_pool tlsf, size_t align, size_t size)
|
|
{
|
|
pool_t* pool = tlsf_cast(pool_t*, tlsf);
|
|
const size_t adjust = adjust_request_size(size, ALIGN_SIZE);
|
|
|
|
/*
|
|
** We must allocate an additional minimum block size bytes so that if
|
|
** our free block will leave an alignment gap which is smaller, we can
|
|
** trim a leading free block and release it back to the heap. We must
|
|
** do this because the previous physical block is in use, therefore
|
|
** the prev_phys_block field is not valid, and we can't simply adjust
|
|
** the size of that block.
|
|
*/
|
|
const size_t gap_minimum = sizeof(block_header_t);
|
|
const size_t size_with_gap = adjust_request_size(adjust + align + gap_minimum, align);
|
|
|
|
/* If alignment is less than or equals base alignment, we're done. */
|
|
const size_t aligned_size = (align <= ALIGN_SIZE) ? adjust : size_with_gap;
|
|
|
|
block_header_t* block = block_locate_free(pool, aligned_size);
|
|
|
|
/* This can't be a static assert. */
|
|
tlsf_assert(sizeof(block_header_t) == block_size_min + block_header_overhead);
|
|
|
|
if (block)
|
|
{
|
|
void* ptr = block_to_ptr(block);
|
|
void* aligned = align_ptr(ptr, align);
|
|
size_t gap = tlsf_cast(size_t,
|
|
tlsf_cast(tlsfptr_t, aligned) - tlsf_cast(tlsfptr_t, ptr));
|
|
|
|
/* If gap size is too small, offset to next aligned boundary. */
|
|
if (gap && gap < gap_minimum)
|
|
{
|
|
const size_t gap_remain = gap_minimum - gap;
|
|
const size_t offset = tlsf_max(gap_remain, align);
|
|
const void* next_aligned = tlsf_cast(void*,
|
|
tlsf_cast(tlsfptr_t, aligned) + offset);
|
|
|
|
aligned = align_ptr(next_aligned, align);
|
|
gap = tlsf_cast(size_t,
|
|
tlsf_cast(tlsfptr_t, aligned) - tlsf_cast(tlsfptr_t, ptr));
|
|
}
|
|
|
|
if (gap)
|
|
{
|
|
tlsf_assert(gap >= gap_minimum && "gap size too small");
|
|
block = block_trim_free_leading(pool, block, gap);
|
|
}
|
|
}
|
|
|
|
return block_prepare_used(pool, block, adjust);
|
|
}
|
|
|
|
void tlsf_free(tlsf_pool tlsf, void* ptr)
|
|
{
|
|
/* Don't attempt to free a NULL pointer. */
|
|
if (ptr)
|
|
{
|
|
pool_t* pool = tlsf_cast(pool_t*, tlsf);
|
|
block_header_t* block = block_from_ptr(ptr);
|
|
block_mark_as_free(block);
|
|
block = block_merge_prev(pool, block);
|
|
block = block_merge_next(pool, block);
|
|
block_insert(pool, block);
|
|
}
|
|
}
|
|
|
|
/*
|
|
** The TLSF block information provides us with enough information to
|
|
** provide a reasonably intelligent implementation of realloc, growing or
|
|
** shrinking the currently allocated block as required.
|
|
**
|
|
** This routine handles the somewhat esoteric edge cases of realloc:
|
|
** - a non-zero size with a null pointer will behave like malloc
|
|
** - a zero size with a non-null pointer will behave like free
|
|
** - a request that cannot be satisfied will leave the original buffer
|
|
** untouched
|
|
** - an extended buffer size will leave the newly-allocated area with
|
|
** contents undefined
|
|
*/
|
|
void* tlsf_realloc(tlsf_pool tlsf, void* ptr, size_t size)
|
|
{
|
|
pool_t* pool = tlsf_cast(pool_t*, tlsf);
|
|
void* p = 0;
|
|
|
|
/* Zero-size requests are treated as free. */
|
|
if (ptr && size == 0)
|
|
{
|
|
tlsf_free(tlsf, ptr);
|
|
}
|
|
/* Requests with NULL pointers are treated as malloc. */
|
|
else if (!ptr)
|
|
{
|
|
p = tlsf_malloc(tlsf, size);
|
|
}
|
|
else
|
|
{
|
|
block_header_t* block = block_from_ptr(ptr);
|
|
block_header_t* next = block_next(block);
|
|
|
|
const size_t cursize = block_size(block);
|
|
const size_t combined = cursize + block_size(next) + block_header_overhead;
|
|
const size_t adjust = adjust_request_size(size, ALIGN_SIZE);
|
|
|
|
/*
|
|
** If the next block is used, or when combined with the current
|
|
** block, does not offer enough space, we must reallocate and copy.
|
|
*/
|
|
if (adjust > cursize && (!block_is_free(next) || adjust > combined))
|
|
{
|
|
p = tlsf_malloc(tlsf, size);
|
|
if (p)
|
|
{
|
|
const size_t minsize = tlsf_min(cursize, size);
|
|
memcpy(p, ptr, minsize);
|
|
tlsf_free(tlsf, ptr);
|
|
}
|
|
}
|
|
else
|
|
{
|
|
/* Do we need to expand to the next block? */
|
|
if (adjust > cursize)
|
|
{
|
|
block_merge_next(pool, block);
|
|
block_mark_as_used(block);
|
|
}
|
|
|
|
/* Trim the resulting block and return the original pointer. */
|
|
block_trim_used(pool, block, adjust);
|
|
p = ptr;
|
|
}
|
|
}
|
|
|
|
return p;
|
|
}
|