static void test_check_free_block(void)
{
Heap_Block *block = NULL;
Heap_Block *next_block = NULL;
Heap_Block *first_free_block = NULL;
Heap_Block *secound_free_block = NULL;
void *p1 = NULL;
puts( "test the _Heap_Walk_check_free_block() function" );
puts( "\tset a previous size for the next block which is not equal to the size of the actual block" );
test_heap_init_default();
block = _Heap_Free_list_first( &TestHeap );
next_block = _Heap_Block_at( block, _Heap_Block_size( block ) );
next_block->prev_size = _Heap_Block_size( block ) - 1;
test_call_heap_walk( false );
puts( "\tclear the previous_used flag of the first free block after an used block" );
test_heap_init_default();
p1 = test_allocate_block();
block = _Heap_Block_of_alloc_area( (uintptr_t) p1, TestHeap.page_size );
first_free_block = _Heap_Free_list_first( &TestHeap );
first_free_block->size_and_flag &= ~HEAP_PREV_BLOCK_USED;
first_free_block->prev_size = _Heap_Block_size( block );
_Heap_Free_list_insert_after( first_free_block, block );
test_call_heap_walk( false );
puts( "\ttake a free block out of the free list" );
test_heap_init_custom();
test_create_heap_with_gaps();
first_free_block = _Heap_Free_list_first( &TestHeap );
secound_free_block = first_free_block->next;
_Heap_Free_list_remove( secound_free_block );
test_call_heap_walk( false );
}
static void test_heap_do_block_allocate( int variant, void *p2 )
{
Heap_Block *const block =
_Heap_Block_of_alloc_area( (uintptr_t) p2, test_page_size());
uintptr_t const alloc_box_begin = _Heap_Alloc_area_of_block( block );
uintptr_t const alloc_box_size = _Heap_Block_size( block );
uintptr_t const alloc_box_end = alloc_box_begin + alloc_box_size;
uintptr_t alloc_begin = 0;
uintptr_t alloc_size = 0;
puts( "\tallocate block at the beginning");
alloc_begin = alloc_box_begin;
alloc_size = 0;
test_block_alloc( variant, 0, alloc_begin, alloc_size );
puts( "\tallocate block full space");
alloc_begin = alloc_box_begin;
alloc_size = alloc_box_size + HEAP_ALLOC_BONUS
- HEAP_BLOCK_HEADER_SIZE;
test_block_alloc( variant, 1, alloc_begin, alloc_size );
puts( "\tallocate block in the middle");
alloc_begin = alloc_box_begin + TEST_DEFAULT_PAGE_SIZE;
alloc_size = 0;
test_block_alloc( variant, 2, alloc_begin, alloc_size );
puts( "\tallocate block at the end");
alloc_begin = alloc_box_end - TEST_DEFAULT_PAGE_SIZE;
alloc_size = TEST_DEFAULT_PAGE_SIZE + HEAP_ALLOC_BONUS
- HEAP_BLOCK_HEADER_SIZE;
test_block_alloc( variant, 3, alloc_begin, alloc_size );
}
Heap_Resize_status _Heap_Resize_block(
Heap_Control *heap,
void *alloc_begin_ptr,
uintptr_t new_alloc_size,
uintptr_t *old_size,
uintptr_t *new_size
)
{
uintptr_t const page_size = heap->page_size;
uintptr_t const alloc_begin = (uintptr_t) alloc_begin_ptr;
Heap_Block *const block = _Heap_Block_of_alloc_area( alloc_begin, page_size );
*old_size = 0;
*new_size = 0;
if ( _Heap_Is_block_in_heap( heap, block ) ) {
_Heap_Protection_block_check( heap, block );
return _Heap_Resize_block_checked(
heap,
block,
alloc_begin,
new_alloc_size,
old_size,
new_size
);
}
return HEAP_RESIZE_FATAL_ERROR;
}
static uintptr_t _Heap_Check_block(
const Heap_Control *heap,
const Heap_Block *block,
uintptr_t alloc_size,
uintptr_t alignment,
uintptr_t boundary
)
{
uintptr_t const page_size = heap->page_size;
uintptr_t const min_block_size = heap->min_block_size;
uintptr_t const block_begin = (uintptr_t) block;
uintptr_t const block_size = _Heap_Block_size( block );
uintptr_t const block_end = block_begin + block_size;
uintptr_t const alloc_begin_floor = _Heap_Alloc_area_of_block( block );
uintptr_t const alloc_begin_ceiling = block_end - min_block_size
+ HEAP_BLOCK_HEADER_SIZE + page_size - 1;
uintptr_t alloc_end = block_end + HEAP_ALLOC_BONUS;
uintptr_t alloc_begin = alloc_end - alloc_size;
alloc_begin = _Heap_Align_down( alloc_begin, alignment );
/* Ensure that the we have a valid new block at the end */
if ( alloc_begin > alloc_begin_ceiling ) {
alloc_begin = _Heap_Align_down( alloc_begin_ceiling, alignment );
}
alloc_end = alloc_begin + alloc_size;
/* Ensure boundary constaint */
if ( boundary != 0 ) {
uintptr_t const boundary_floor = alloc_begin_floor + alloc_size;
uintptr_t boundary_line = _Heap_Align_down( alloc_end, boundary );
while ( alloc_begin < boundary_line && boundary_line < alloc_end ) {
if ( boundary_line < boundary_floor ) {
return 0;
}
alloc_begin = boundary_line - alloc_size;
alloc_begin = _Heap_Align_down( alloc_begin, alignment );
alloc_end = alloc_begin + alloc_size;
boundary_line = _Heap_Align_down( alloc_end, boundary );
}
}
/* Ensure that the we have a valid new block at the beginning */
if ( alloc_begin >= alloc_begin_floor ) {
uintptr_t const alloc_block_begin =
(uintptr_t) _Heap_Block_of_alloc_area( alloc_begin, page_size );
uintptr_t const free_size = alloc_block_begin - block_begin;
if ( free_size >= min_block_size || free_size == 0 ) {
return alloc_begin;
}
}
return 0;
}
bool _Heap_Size_of_alloc_area(
Heap_Control *heap,
void *alloc_begin_ptr,
uintptr_t *alloc_size
)
{
uintptr_t const page_size = heap->page_size;
uintptr_t const alloc_begin = (uintptr_t) alloc_begin_ptr;
Heap_Block *block = _Heap_Block_of_alloc_area( alloc_begin, page_size );
Heap_Block *next_block = NULL;
uintptr_t block_size = 0;
if ( !_Heap_Is_block_in_heap( heap, block ) ) {
return false;
}
block_size = _Heap_Block_size( block );
next_block = _Heap_Block_at( block, block_size );
if (
!_Heap_Is_block_in_heap( heap, next_block )
|| !_Heap_Is_prev_used( next_block )
) {
return false;
}
*alloc_size = (uintptr_t) next_block + HEAP_BLOCK_SIZE_OFFSET - alloc_begin;
return true;
}
static Heap_Block *_Heap_Block_allocate_from_end(
Heap_Control *heap,
Heap_Block *block,
Heap_Block *free_list_anchor,
uintptr_t alloc_begin,
uintptr_t alloc_size
)
{
Heap_Statistics *const stats = &heap->stats;
uintptr_t block_begin = (uintptr_t) block;
uintptr_t block_size = _Heap_Block_size( block );
uintptr_t block_end = block_begin + block_size;
Heap_Block *const new_block =
_Heap_Block_of_alloc_area( alloc_begin, heap->page_size );
uintptr_t const new_block_begin = (uintptr_t) new_block;
uintptr_t const new_block_size = block_end - new_block_begin;
block_end = new_block_begin;
block_size = block_end - block_begin;
_HAssert( block_size >= heap->min_block_size );
_HAssert( new_block_size >= heap->min_block_size );
/* Statistics */
stats->free_size += block_size;
if ( _Heap_Is_prev_used( block ) ) {
_Heap_Free_list_insert_after( free_list_anchor, block );
free_list_anchor = block;
/* Statistics */
++stats->free_blocks;
} else {
Heap_Block *const prev_block = _Heap_Prev_block( block );
uintptr_t const prev_block_size = _Heap_Block_size( prev_block );
block = prev_block;
block_begin = (uintptr_t) block;
block_size += prev_block_size;
}
block->size_and_flag = block_size | HEAP_PREV_BLOCK_USED;
new_block->prev_size = block_size;
new_block->size_and_flag = new_block_size;
_Heap_Block_split( heap, new_block, free_list_anchor, alloc_size );
return new_block;
}
static void test_check_free_list(void)
{
void *p1 = NULL;
Heap_Block *first_free_block = NULL;
Heap_Block *secound_free_block = NULL;
Heap_Block *third_free_block = NULL;
Heap_Block *used_block = NULL;
puts( "testing the _Heap_Walk_check_free_list() function" );
puts( "\tno free blocks" );
test_heap_init_custom();
test_fill_heap();
test_call_heap_walk( true );
puts( "\tcreate a loop in the free list" );
test_heap_init_default();
test_create_heap_with_gaps();
/* find free blocks */
first_free_block = _Heap_Free_list_first( &TestHeap );
secound_free_block = first_free_block->next;
third_free_block = secound_free_block->next;
/* create a loop */
third_free_block->next = secound_free_block;
secound_free_block->prev = third_free_block;
test_call_heap_walk( false );
puts( "\tput a block outside the heap to the free list" );
test_heap_init_default();
first_free_block = _Heap_Free_list_first( &TestHeap );
first_free_block->next = TestHeap.first_block - 1;
test_call_heap_walk( false );
puts( "\tput a block on the free list, which is not page-aligned" );
test_heap_init_custom();
test_create_heap_with_gaps();
first_free_block = _Heap_Free_list_first( &TestHeap );
first_free_block->next = (Heap_Block *) ((uintptr_t) first_free_block->next + CPU_ALIGNMENT);
first_free_block->next->prev = first_free_block;
test_call_heap_walk( false );
puts( "\tput a used block on the free list" );
test_heap_init_custom();
test_create_heap_with_gaps();
p1 = test_allocate_block();
first_free_block = _Heap_Free_list_first( &TestHeap );
used_block = _Heap_Block_of_alloc_area( (uintptr_t) p1, TestHeap.page_size );
_Heap_Free_list_insert_after( first_free_block, used_block );
test_call_heap_walk( false );
}
Heap_Block *_Heap_Greedy_allocate(
Heap_Control *heap,
const uintptr_t *block_sizes,
size_t block_count
)
{
Heap_Block *const free_list_tail = _Heap_Free_list_tail( heap );
Heap_Block *allocated_blocks = NULL;
Heap_Block *blocks = NULL;
Heap_Block *current;
size_t i;
_Heap_Protection_free_all_delayed_blocks( heap );
for (i = 0; i < block_count; ++i) {
void *next = _Heap_Allocate( heap, block_sizes [i] );
if ( next != NULL ) {
Heap_Block *next_block = _Heap_Block_of_alloc_area(
(uintptr_t) next,
heap->page_size
);
next_block->next = allocated_blocks;
allocated_blocks = next_block;
}
}
while ( (current = _Heap_Free_list_first( heap )) != free_list_tail ) {
_Heap_Block_allocate(
heap,
current,
_Heap_Alloc_area_of_block( current ),
_Heap_Block_size( current ) - HEAP_BLOCK_HEADER_SIZE
);
current->next = blocks;
blocks = current;
}
while ( allocated_blocks != NULL ) {
current = allocated_blocks;
allocated_blocks = allocated_blocks->next;
_Heap_Free( heap, (void *) _Heap_Alloc_area_of_block( current ) );
}
return blocks;
}
static void test_heap_free(void)
{
Heap_Control *heap = &TestHeap;
void *p;
Heap_Block *block;
bool ok;
_Heap_Initialize( heap, &TestHeapMemory[0], sizeof(TestHeapMemory), 0 );
p = _Heap_Allocate( heap, 1 );
rtems_test_assert( p != NULL );
block = _Heap_Block_of_alloc_area( (uintptr_t) p, heap->page_size );
/*
* This will kick the next block outside of the heap area and the next
* _Heap_Free() will detect this.
*/
block->size_and_flag += sizeof(TestHeapMemory);
ok = _Heap_Free( heap, p );
rtems_test_assert( !ok );
}
static void test_heap_resize_block(void)
{
void *p1, *p2, *p3;
uintptr_t new_alloc_size = 0;
Heap_Block *block = NULL;
puts( "run tests for _Heap_Resize_Block()" );
puts( "\tgive a block outside the heap to the function" );
test_heap_init( TEST_DEFAULT_PAGE_SIZE );
p1 = TestHeap.first_block - TEST_DEFAULT_PAGE_SIZE;
new_alloc_size = 1;
test_simple_resize_block( p1, new_alloc_size, HEAP_RESIZE_FATAL_ERROR );
puts( "\tincrease size");
puts( "\t\tlet the next block be used alredy and try to get a size bigger than the actual block" );
test_heap_init( TEST_DEFAULT_PAGE_SIZE );
p1 = test_alloc_one_page();
rtems_test_assert( p1 );
p2 = test_alloc_one_page();
rtems_test_assert( p2 );
new_alloc_size = 3 * TEST_DEFAULT_PAGE_SIZE / 2;
test_simple_resize_block( p1, new_alloc_size, HEAP_RESIZE_UNSATISFIED );
puts( "\t\tnext block not used and try to set the new allocation size between the page-alignments" );
test_heap_init( TEST_DEFAULT_PAGE_SIZE );
p1 = test_alloc_one_page();
new_alloc_size = 3 * TEST_DEFAULT_PAGE_SIZE / 2;
test_simple_resize_block( p1, new_alloc_size, HEAP_RESIZE_SUCCESSFUL );
puts( "\t\tlet the block after the next be used and try to allocate more then one pagesize more" );
test_heap_init( TEST_DEFAULT_PAGE_SIZE );
p1 = test_alloc_one_page();
rtems_test_assert( p1 );
p2 = test_alloc_one_page();
rtems_test_assert( p2 );
p3 = test_alloc_one_page();
rtems_test_assert( p3 );
test_free( p2 );
new_alloc_size = 5 * TEST_DEFAULT_PAGE_SIZE / 2;
test_simple_resize_block( p1, new_alloc_size, HEAP_RESIZE_UNSATISFIED );
puts( "\ttry to resize to the same size" );
test_heap_init( TEST_DEFAULT_PAGE_SIZE );
p1 = test_alloc_one_page();
block = _Heap_Block_of_alloc_area( (uintptr_t) p1, TestHeap.page_size );
new_alloc_size = _Heap_Block_size( block );
test_simple_resize_block( p1, new_alloc_size, HEAP_RESIZE_SUCCESSFUL );
puts( "\tdecrease size");
puts( "\t\tdecrease a block with two pages to one page" );
test_heap_init( TEST_DEFAULT_PAGE_SIZE );
p1 = test_alloc_two_pages();
new_alloc_size = 1;
test_simple_resize_block( p1, new_alloc_size, HEAP_RESIZE_SUCCESSFUL );
puts( "\t\tresize the block to the size 0" );
test_heap_init( TEST_DEFAULT_PAGE_SIZE );
p1 = test_alloc_one_page();
new_alloc_size = 0;
test_simple_resize_block( p1, new_alloc_size, HEAP_RESIZE_SUCCESSFUL );
}
static void test_block_alloc(
int free_variant,
int alloc_variant,
uintptr_t alloc_begin,
uintptr_t alloc_size
)
{
void *p1 = NULL;
void *p2 = NULL;
void *p3 = NULL;
uintptr_t size_fresh_heap = 0;
uintptr_t pages_per_default_block = 0;
uint32_t exp_free_pages = 0;
uint32_t exp_free_blocks = 0;
uint32_t exp_used_blocks = 0;
test_heap_init( TEST_DEFAULT_PAGE_SIZE );
size_fresh_heap = _Heap_Get_size( &TestHeap );
exp_free_pages = size_fresh_heap / TestHeap.page_size;
p1 = test_create_used_block();
p2 = test_create_used_block();
p3 = test_create_used_block();
pages_per_default_block = _Heap_Block_size(
_Heap_Block_of_alloc_area( (uintptr_t) p1, TestHeap.page_size )
) / TestHeap.page_size;
if (free_variant == 1) {
test_free( p1 );
} else if (free_variant == 2) {
test_free( p3 );
} else if (free_variant == 3) {
test_free( p2 );
test_free( p3 );
}
_Heap_Block_allocate(
&TestHeap,
_Heap_Block_of_alloc_area( (uintptr_t) p2, test_page_size()),
alloc_begin,
alloc_size
);
test_check_alloc_simple( (void *) alloc_begin, alloc_size, 0, 0 );
/* check statistics */
switch( free_variant ) {
case 1:
exp_free_pages = exp_free_pages - 2 * pages_per_default_block;
exp_used_blocks = 2;
switch( alloc_variant ) {
case 1:
/* allocate block full space */
exp_free_blocks = 2;
break;
case 2:
/* allocate block in the middle */
exp_free_pages = exp_free_pages + pages_per_default_block - 1;
exp_free_blocks = 3;
break;
case 3:
/* allocate block at the end */
exp_free_pages = exp_free_pages + pages_per_default_block - 2;
exp_free_blocks = 2;
break;
default:
/* allocate block at the beginning */
exp_free_pages = exp_free_pages + pages_per_default_block - 1;
exp_free_blocks = 3;
break;
}
break;
case 2:
exp_free_pages = exp_free_pages - 2 * pages_per_default_block;
exp_used_blocks = 2;
switch( alloc_variant ) {
case 1:
/* allocate block full space */
exp_free_blocks = 1;
break;
case 2:
/* allocate block in the middle */
exp_free_pages = exp_free_pages + pages_per_default_block - 1;
exp_free_blocks = 2;
break;
case 3:
/* allocate block at the end */
exp_free_pages = exp_free_pages + pages_per_default_block - 1;
exp_free_blocks = 2;
break;
default:
/* allocate block at the beginning */
exp_free_pages = exp_free_pages + pages_per_default_block - 1;
exp_free_blocks = 1;
break;
}
break;
case 3:
exp_free_pages = exp_free_pages - pages_per_default_block;
exp_used_blocks = 2;
switch( alloc_variant ) {
case 1:
/* allocate block full space */
exp_free_pages = exp_free_pages - pages_per_default_block;
exp_free_blocks = 1;
break;
case 2:
/* allocate block in the middle */
exp_free_pages = exp_free_pages - 1;
exp_free_blocks = 2;
break;
case 3:
/* allocate block at the end */
exp_free_pages = exp_free_pages - 2;
exp_free_blocks = 2;
break;
default:
/* allocate block at the beginning */
exp_free_pages = exp_free_pages - 1;
exp_free_blocks = 1;
break;
}
break;
default:
exp_free_pages = exp_free_pages - 3 * pages_per_default_block;
exp_used_blocks = 3;
switch( alloc_variant ) {
case 1:
/* allocate block full space */
exp_free_blocks = 1;
break;
case 2:
/* allocate block in the middle */
exp_free_blocks = 3;
exp_free_pages = exp_free_pages + pages_per_default_block - 1;
break;
case 3:
/* allocate block at the end */
exp_free_blocks = 2;
exp_free_pages = exp_free_pages + pages_per_default_block - 1;
break;
default:
/* allocate block at the beginning */
exp_free_blocks = 2;
exp_free_pages = exp_free_pages + pages_per_default_block - 1;
}
}
rtems_test_assert( TestHeap.stats.free_size == exp_free_pages * TestHeap.page_size );
rtems_test_assert( TestHeap.stats.free_blocks == exp_free_blocks );
rtems_test_assert( TestHeap.stats.used_blocks == exp_used_blocks );
}
static void test_check_alloc(
void *alloc_begin_ptr,
void *expected_alloc_begin_ptr,
uintptr_t alloc_size,
uintptr_t alignment,
uintptr_t boundary
)
{
uintptr_t const min_block_size = TestHeap.min_block_size;
uintptr_t const page_size = TestHeap.page_size;
rtems_test_assert( alloc_begin_ptr == expected_alloc_begin_ptr );
if( expected_alloc_begin_ptr != NULL ) {
uintptr_t const alloc_begin = (uintptr_t ) alloc_begin_ptr;
uintptr_t const alloc_end = alloc_begin + alloc_size;
uintptr_t const alloc_area_begin = _Heap_Align_down( alloc_begin, page_size );
uintptr_t const alloc_area_offset = alloc_begin - alloc_area_begin;
#if UNUSED
uintptr_t const alloc_area_size = alloc_area_offset + alloc_size;
#endif
Heap_Block *block = _Heap_Block_of_alloc_area( alloc_area_begin, page_size );
uintptr_t const block_begin = (uintptr_t ) block;
uintptr_t const block_size = _Heap_Block_size( block );
uintptr_t const block_end = block_begin + block_size;
rtems_test_assert( block_size >= min_block_size );
rtems_test_assert( block_begin < block_end );
rtems_test_assert(
_Heap_Is_aligned( block_begin + HEAP_BLOCK_HEADER_SIZE, page_size )
);
rtems_test_assert(
_Heap_Is_aligned( block_size, page_size )
);
rtems_test_assert( alloc_end <= block_end + HEAP_ALLOC_BONUS );
rtems_test_assert( alloc_area_begin > block_begin );
rtems_test_assert( alloc_area_offset < page_size );
rtems_test_assert( _Heap_Is_aligned( alloc_area_begin, page_size ) );
if ( alignment == 0 ) {
rtems_test_assert( alloc_begin == alloc_area_begin );
} else {
rtems_test_assert( _Heap_Is_aligned( alloc_begin, alignment ) );
}
if ( boundary != 0 ) {
uintptr_t boundary_line = _Heap_Align_down( alloc_end, boundary );
rtems_test_assert( alloc_size <= boundary );
rtems_test_assert(
boundary_line <= alloc_begin
|| alloc_end <= boundary_line
);
}
}
rtems_test_assert(
page_size < CPU_ALIGNMENT
|| _Heap_Walk( &TestHeap, 0, false )
);
}
bool _Heap_Free( Heap_Control *heap, void *alloc_begin_ptr )
{
Heap_Statistics *const stats = &heap->stats;
uintptr_t alloc_begin = (uintptr_t) alloc_begin_ptr;
Heap_Block *block =
_Heap_Block_of_alloc_area( alloc_begin, heap->page_size );
Heap_Block *next_block = NULL;
uintptr_t block_size = 0;
uintptr_t next_block_size = 0;
bool next_is_free = false;
if ( !_Heap_Is_block_in_heap( heap, block ) ) {
return false;
}
block_size = _Heap_Block_size( block );
next_block = _Heap_Block_at( block, block_size );
if ( !_Heap_Is_block_in_heap( heap, next_block ) ) {
_HAssert( false );
return false;
}
if ( !_Heap_Is_prev_used( next_block ) ) {
_HAssert( false );
return false;
}
next_block_size = _Heap_Block_size( next_block );
next_is_free = next_block != heap->last_block
&& !_Heap_Is_prev_used( _Heap_Block_at( next_block, next_block_size ));
if ( !_Heap_Is_prev_used( block ) ) {
uintptr_t const prev_size = block->prev_size;
Heap_Block * const prev_block = _Heap_Block_at( block, -prev_size );
if ( !_Heap_Is_block_in_heap( heap, prev_block ) ) {
_HAssert( false );
return( false );
}
/* As we always coalesce free blocks, the block that preceedes prev_block
must have been used. */
if ( !_Heap_Is_prev_used ( prev_block) ) {
_HAssert( false );
return( false );
}
if ( next_is_free ) { /* coalesce both */
uintptr_t const size = block_size + prev_size + next_block_size;
_Heap_Free_list_remove( next_block );
stats->free_blocks -= 1;
prev_block->size_and_flag = size | HEAP_PREV_BLOCK_USED;
next_block = _Heap_Block_at( prev_block, size );
_HAssert(!_Heap_Is_prev_used( next_block));
next_block->prev_size = size;
} else { /* coalesce prev */
uintptr_t const size = block_size + prev_size;
prev_block->size_and_flag = size | HEAP_PREV_BLOCK_USED;
next_block->size_and_flag &= ~HEAP_PREV_BLOCK_USED;
next_block->prev_size = size;
}
} else if ( next_is_free ) { /* coalesce next */
uintptr_t const size = block_size + next_block_size;
_Heap_Free_list_replace( next_block, block );
block->size_and_flag = size | HEAP_PREV_BLOCK_USED;
next_block = _Heap_Block_at( block, size );
next_block->prev_size = size;
} else { /* no coalesce */
/* Add 'block' to the head of the free blocks list as it tends to
produce less fragmentation than adding to the tail. */
_Heap_Free_list_insert_after( _Heap_Free_list_head( heap), block );
block->size_and_flag = block_size | HEAP_PREV_BLOCK_USED;
next_block->size_and_flag &= ~HEAP_PREV_BLOCK_USED;
next_block->prev_size = block_size;
/* Statistics */
++stats->free_blocks;
if ( stats->max_free_blocks < stats->free_blocks ) {
stats->max_free_blocks = stats->free_blocks;
}
}
/* Statistics */
--stats->used_blocks;
++stats->frees;
stats->free_size += block_size;
return( true );
}
uintptr_t _Heap_Extend(
Heap_Control *heap,
void *extend_area_begin_ptr,
uintptr_t extend_area_size,
uintptr_t unused __attribute__((unused))
)
{
Heap_Statistics *const stats = &heap->stats;
Heap_Block *const first_block = heap->first_block;
Heap_Block *start_block = first_block;
Heap_Block *merge_below_block = NULL;
Heap_Block *merge_above_block = NULL;
Heap_Block *link_below_block = NULL;
Heap_Block *link_above_block = NULL;
Heap_Block *extend_first_block = NULL;
Heap_Block *extend_last_block = NULL;
uintptr_t const page_size = heap->page_size;
uintptr_t const min_block_size = heap->min_block_size;
uintptr_t const extend_area_begin = (uintptr_t) extend_area_begin_ptr;
uintptr_t const extend_area_end = extend_area_begin + extend_area_size;
uintptr_t const free_size = stats->free_size;
uintptr_t extend_first_block_size = 0;
uintptr_t extended_size = 0;
bool extend_area_ok = false;
if ( extend_area_end < extend_area_begin ) {
return 0;
}
extend_area_ok = _Heap_Get_first_and_last_block(
extend_area_begin,
extend_area_size,
page_size,
min_block_size,
&extend_first_block,
&extend_last_block
);
if (!extend_area_ok ) {
/* For simplicity we reject extend areas that are too small */
return 0;
}
do {
uintptr_t const sub_area_begin = (start_block != first_block) ?
(uintptr_t) start_block : heap->area_begin;
uintptr_t const sub_area_end = start_block->prev_size;
Heap_Block *const end_block =
_Heap_Block_of_alloc_area( sub_area_end, page_size );
if (
sub_area_end > extend_area_begin && extend_area_end > sub_area_begin
) {
return 0;
}
if ( extend_area_end == sub_area_begin ) {
merge_below_block = start_block;
} else if ( extend_area_end < sub_area_end ) {
link_below_block = start_block;
}
if ( sub_area_end == extend_area_begin ) {
start_block->prev_size = extend_area_end;
merge_above_block = end_block;
} else if ( sub_area_end < extend_area_begin ) {
link_above_block = end_block;
}
start_block = _Heap_Block_at( end_block, _Heap_Block_size( end_block ) );
} while ( start_block != first_block );
if ( extend_area_begin < heap->area_begin ) {
heap->area_begin = extend_area_begin;
} else if ( heap->area_end < extend_area_end ) {
heap->area_end = extend_area_end;
}
extend_first_block_size =
(uintptr_t) extend_last_block - (uintptr_t) extend_first_block;
extend_first_block->prev_size = extend_area_end;
extend_first_block->size_and_flag =
extend_first_block_size | HEAP_PREV_BLOCK_USED;
_Heap_Protection_block_initialize( heap, extend_first_block );
extend_last_block->prev_size = extend_first_block_size;
extend_last_block->size_and_flag = 0;
_Heap_Protection_block_initialize( heap, extend_last_block );
if ( (uintptr_t) extend_first_block < (uintptr_t) heap->first_block ) {
heap->first_block = extend_first_block;
} else if ( (uintptr_t) extend_last_block > (uintptr_t) heap->last_block ) {
heap->last_block = extend_last_block;
}
if ( merge_below_block != NULL ) {
_Heap_Merge_below( heap, extend_area_begin, merge_below_block );
} else if ( link_below_block != NULL ) {
_Heap_Link_below(
link_below_block,
extend_last_block
);
}
if ( merge_above_block != NULL ) {
_Heap_Merge_above( heap, merge_above_block, extend_area_end );
} else if ( link_above_block != NULL ) {
_Heap_Link_above(
link_above_block,
extend_first_block,
extend_last_block
);
}
if ( merge_below_block == NULL && merge_above_block == NULL ) {
_Heap_Free_block( heap, extend_first_block );
}
_Heap_Set_last_block_size( heap );
extended_size = stats->free_size - free_size;
/* Statistics */
stats->size += extended_size;
return extended_size;
}
static void test_main_loop(void)
{
void *p1 = NULL;
void *p2 = NULL;
Heap_Block *block = NULL;
Heap_Block *next_block = NULL;
puts( "Test the main loop" );
puts( "\tset the blocksize so, that the next block is outside the heap" );
test_heap_init_custom();
/* use all blocks */
p1 = test_fill_heap();
block = _Heap_Block_of_alloc_area( (uintptr_t) p1, TestHeap.page_size );
block->size_and_flag = ( 2 * _Heap_Block_size( block ) ) | HEAP_PREV_BLOCK_USED;
test_call_heap_walk( false );
puts( "\twalk a heap with blocks with different states of the previous-used flag" );
test_heap_init_custom();
test_create_heap_with_gaps();
test_allocate_block(); /* fill one gap */
test_call_heap_walk( true );
puts( "\tcreate a block with a not page aligned size" );
test_heap_init_custom();
p1 = test_allocate_block();
p2 = test_allocate_block();
_Heap_Free( &TestHeap, p1 );
block = _Heap_Block_of_alloc_area( (uintptr_t) p2, TestHeap.page_size );
block->size_and_flag = (3 * TestHeap.page_size / 2) & ~HEAP_PREV_BLOCK_USED;
test_call_heap_walk( false );
puts( "\tcreate a block with a size smaller than the min_block_size" );
test_heap_init_default();
p1 = test_allocate_block();
p2 = test_allocate_block();
_Heap_Free( &TestHeap, p1 );
block = _Heap_Block_of_alloc_area( (uintptr_t) p2, TestHeap.page_size );
block->size_and_flag = 0;
test_call_heap_walk( false );
puts( "\tmake a block with a size, so that the block reaches into the next block" );
test_heap_init_default();
p1 = test_allocate_block();
p2 = test_allocate_block();
block = _Heap_Block_of_alloc_area( (uintptr_t) p1, TestHeap.page_size );
block->size_and_flag = ( 3 * _Heap_Block_size( block ) / 2 ) | HEAP_PREV_BLOCK_USED;
test_call_heap_walk( false );
puts( "\tcreate a block with invalid successor" );
test_heap_init_default();
test_allocate_block();
p1 = test_allocate_block();
block = _Heap_Block_of_alloc_area( (uintptr_t) p1, TestHeap.page_size );
block->size_and_flag = (0 - TestHeap.page_size) | HEAP_PREV_BLOCK_USED;
test_call_heap_walk( false );
puts( "\tmake a block with a size, so that it includes the next block" );
test_heap_init_default();
p1 = test_allocate_block();
p2 = test_allocate_block();
block = _Heap_Block_of_alloc_area( (uintptr_t) p1, TestHeap.page_size );
next_block = _Heap_Block_at( block, _Heap_Block_size( block ) );
block->size_and_flag = ( _Heap_Block_size( block ) + _Heap_Block_size( next_block ) ) | HEAP_PREV_BLOCK_USED;
test_call_heap_walk( true );
}
bool _Heap_Free( Heap_Control *heap, void *alloc_begin_ptr )
{
Heap_Statistics *const stats = &heap->stats;
uintptr_t alloc_begin;
Heap_Block *block;
Heap_Block *next_block = NULL;
uintptr_t block_size = 0;
uintptr_t next_block_size = 0;
bool next_is_free = false;
/*
* If NULL return true so a free on NULL is considered a valid release. This
* is a special case that could be handled by the in heap check how-ever that
* would result in false being returned which is wrong.
*/
if ( alloc_begin_ptr == NULL ) {
return true;
}
alloc_begin = (uintptr_t) alloc_begin_ptr;
block = _Heap_Block_of_alloc_area( alloc_begin, heap->page_size );
if ( !_Heap_Is_block_in_heap( heap, block ) ) {
return false;
}
_Heap_Protection_block_check( heap, block );
block_size = _Heap_Block_size( block );
next_block = _Heap_Block_at( block, block_size );
if ( !_Heap_Is_block_in_heap( heap, next_block ) ) {
return false;
}
_Heap_Protection_block_check( heap, next_block );
if ( !_Heap_Is_prev_used( next_block ) ) {
_Heap_Protection_block_error( heap, block );
return false;
}
if ( !_Heap_Protection_determine_block_free( heap, block ) ) {
return true;
}
next_block_size = _Heap_Block_size( next_block );
next_is_free = next_block != heap->last_block
&& !_Heap_Is_prev_used( _Heap_Block_at( next_block, next_block_size ));
if ( !_Heap_Is_prev_used( block ) ) {
uintptr_t const prev_size = block->prev_size;
Heap_Block * const prev_block = _Heap_Block_at( block, -prev_size );
if ( !_Heap_Is_block_in_heap( heap, prev_block ) ) {
_HAssert( false );
return( false );
}
/* As we always coalesce free blocks, the block that preceedes prev_block
must have been used. */
if ( !_Heap_Is_prev_used ( prev_block) ) {
_HAssert( false );
return( false );
}
if ( next_is_free ) { /* coalesce both */
uintptr_t const size = block_size + prev_size + next_block_size;
_Heap_Free_list_remove( next_block );
stats->free_blocks -= 1;
prev_block->size_and_flag = size | HEAP_PREV_BLOCK_USED;
next_block = _Heap_Block_at( prev_block, size );
_HAssert(!_Heap_Is_prev_used( next_block));
next_block->prev_size = size;
} else { /* coalesce prev */
uintptr_t const size = block_size + prev_size;
prev_block->size_and_flag = size | HEAP_PREV_BLOCK_USED;
next_block->size_and_flag &= ~HEAP_PREV_BLOCK_USED;
next_block->prev_size = size;
}
} else if ( next_is_free ) { /* coalesce next */
uintptr_t const size = block_size + next_block_size;
_Heap_Free_list_replace( next_block, block );
block->size_and_flag = size | HEAP_PREV_BLOCK_USED;
next_block = _Heap_Block_at( block, size );
next_block->prev_size = size;
} else { /* no coalesce */
/* Add 'block' to the head of the free blocks list as it tends to
produce less fragmentation than adding to the tail. */
_Heap_Free_list_insert_after( _Heap_Free_list_head( heap), block );
block->size_and_flag = block_size | HEAP_PREV_BLOCK_USED;
next_block->size_and_flag &= ~HEAP_PREV_BLOCK_USED;
next_block->prev_size = block_size;
/* Statistics */
++stats->free_blocks;
if ( stats->max_free_blocks < stats->free_blocks ) {
stats->max_free_blocks = stats->free_blocks;
}
}
/* Statistics */
--stats->used_blocks;
++stats->frees;
stats->free_size += block_size;
return( true );
}