static gboolean
ms_alloc_block (int size_index, gboolean pinned, gboolean has_references)
{
int size = block_obj_sizes [size_index];
int count = MS_BLOCK_FREE / size;
MSBlockInfo *info;
#ifndef FIXED_HEAP
MSBlockHeader *header;
#endif
MSBlockInfo **free_blocks = FREE_BLOCKS (pinned, has_references);
char *obj_start;
int i;
if (!mono_sgen_try_alloc_space (MS_BLOCK_SIZE, SPACE_MAJOR))
return FALSE;
#ifdef FIXED_HEAP
info = ms_get_empty_block ();
#else
info = mono_sgen_alloc_internal (INTERNAL_MEM_MS_BLOCK_INFO);
#endif
DEBUG (9, g_assert (count >= 2));
info->obj_size = size;
info->obj_size_index = size_index;
info->pinned = pinned;
info->has_references = has_references;
info->has_pinned = pinned;
info->is_to_space = (mono_sgen_get_current_collection_generation () == GENERATION_OLD);
#ifndef FIXED_HEAP
info->block = ms_get_empty_block ();
header = (MSBlockHeader*) info->block;
header->info = info;
#endif
update_heap_boundaries_for_block (info);
/* build free list */
obj_start = info->block + MS_BLOCK_SKIP;
info->free_list = (void**)obj_start;
/* we're skipping the last one - it must be nulled */
for (i = 0; i < count - 1; ++i) {
char *next_obj_start = obj_start + size;
*(void**)obj_start = next_obj_start;
obj_start = next_obj_start;
}
/* the last one */
*(void**)obj_start = NULL;
info->next_free = free_blocks [size_index];
free_blocks [size_index] = info;
info->next = all_blocks;
all_blocks = info;
++num_major_sections;
return TRUE;
}
static void
ms_alloc_block (int size_index, gboolean pinned, gboolean has_references)
{
int size = block_obj_sizes [size_index];
int count = MS_BLOCK_FREE / size;
#ifdef FIXED_HEAP
MSBlockInfo *info = ms_get_empty_block ();
#else
MSBlockInfo *info = mono_sgen_alloc_internal (INTERNAL_MEM_MS_BLOCK_INFO);
MSBlockHeader *header;
#endif
MSBlockInfo **free_blocks = FREE_BLOCKS (pinned, has_references);
char *obj_start;
int i;
DEBUG (9, g_assert (count >= 2));
info->obj_size = size;
info->pinned = pinned;
info->has_references = has_references;
#ifndef FIXED_HEAP
info->block = ms_get_empty_block ();
header = (MSBlockHeader*) info->block;
header->info = info;
#endif
/* build free list */
obj_start = info->block + MS_BLOCK_SKIP;
info->free_list = (void**)obj_start;
/* we're skipping the last one - it must be nulled */
for (i = 0; i < count - 1; ++i) {
char *next_obj_start = obj_start + size;
*(void**)obj_start = next_obj_start;
obj_start = next_obj_start;
}
/* the last one */
*(void**)obj_start = NULL;
info->next_free = free_blocks [size_index];
free_blocks [size_index] = info;
#ifndef FIXED_HEAP
info->next = all_blocks;
all_blocks = info;
#endif
++num_major_sections;
}
static void*
alloc_obj (int size, gboolean pinned, gboolean has_references)
{
int size_index = MS_BLOCK_OBJ_SIZE_INDEX (size);
MSBlockInfo **free_blocks = FREE_BLOCKS (pinned, has_references);
MSBlockInfo *block;
void *obj;
/* FIXME: try to do this without locking */
LOCK_MS_BLOCK_LIST;
g_assert (!ms_sweep_in_progress);
if (!free_blocks [size_index]) {
if (G_UNLIKELY (!ms_alloc_block (size_index, pinned, has_references))) {
UNLOCK_MS_BLOCK_LIST;
return NULL;
}
}
block = free_blocks [size_index];
DEBUG (9, g_assert (block));
obj = block->free_list;
DEBUG (9, g_assert (obj));
block->free_list = *(void**)obj;
if (!block->free_list) {
free_blocks [size_index] = block->next_free;
block->next_free = NULL;
}
UNLOCK_MS_BLOCK_LIST;
/*
* FIXME: This should not be necessary because it'll be
* overwritten by the vtable immediately.
*/
*(void**)obj = NULL;
return obj;
}
/*
* We're not freeing the block if it's empty. We leave that work for
* the next major collection.
*
* This is just called from the domain clearing code, which runs in a
* single thread and has the GC lock, so we don't need an extra lock.
*/
static void
free_object (char *obj, size_t size, gboolean pinned)
{
MSBlockInfo *block = MS_BLOCK_FOR_OBJ (obj);
int word, bit;
DEBUG (9, g_assert ((pinned && block->pinned) || (!pinned && !block->pinned)));
DEBUG (9, g_assert (MS_OBJ_ALLOCED (obj, block)));
MS_CALC_MARK_BIT (word, bit, obj);
DEBUG (9, g_assert (!MS_MARK_BIT (block, word, bit)));
if (!block->free_list) {
MSBlockInfo **free_blocks = FREE_BLOCKS (pinned, block->has_references);
int size_index = MS_BLOCK_OBJ_SIZE_INDEX (size);
DEBUG (9, g_assert (!block->next_free));
block->next_free = free_blocks [size_index];
free_blocks [size_index] = block;
}
memset (obj, 0, size);
*(void**)obj = block->free_list;
block->free_list = (void**)obj;
}
static void
major_sweep (void)
{
int i;
#ifdef FIXED_HEAP
int j;
#else
MSBlockInfo **iter;
#endif
/* clear all the free lists */
for (i = 0; i < MS_BLOCK_TYPE_MAX; ++i) {
MSBlockInfo **free_blocks = free_block_lists [i];
int j;
for (j = 0; j < num_block_obj_sizes; ++j)
free_blocks [j] = NULL;
}
/* traverse all blocks, free and zero unmarked objects */
#ifdef FIXED_HEAP
for (j = 0; j < ms_heap_num_blocks; ++j) {
MSBlockInfo *block = &block_infos [j];
#else
iter = &all_blocks;
while (*iter) {
MSBlockInfo *block = *iter;
#endif
int count;
gboolean have_live = FALSE;
int obj_index;
#ifdef FIXED_HEAP
if (!block->used)
continue;
#endif
count = MS_BLOCK_FREE / block->obj_size;
block->free_list = NULL;
for (obj_index = 0; obj_index < count; ++obj_index) {
int word, bit;
void *obj = MS_BLOCK_OBJ (block, obj_index);
MS_CALC_MARK_BIT (word, bit, obj);
if (MS_MARK_BIT (block, word, bit)) {
DEBUG (9, g_assert (MS_OBJ_ALLOCED (obj, block)));
have_live = TRUE;
} else {
/* an unmarked object */
if (MS_OBJ_ALLOCED (obj, block)) {
binary_protocol_empty (obj, block->obj_size);
memset (obj, 0, block->obj_size);
}
*(void**)obj = block->free_list;
block->free_list = obj;
}
}
/* reset mark bits */
memset (block->mark_words, 0, sizeof (mword) * MS_NUM_MARK_WORDS);
/*
* FIXME: reverse free list so that it's in address
* order
*/
if (have_live) {
#ifndef FIXED_HEAP
iter = &block->next;
#endif
/*
* If there are free slots in the block, add
* the block to the corresponding free list.
*/
if (block->free_list) {
MSBlockInfo **free_blocks = FREE_BLOCKS (block->pinned, block->has_references);
int index = MS_BLOCK_OBJ_SIZE_INDEX (block->obj_size);
block->next_free = free_blocks [index];
free_blocks [index] = block;
}
} else {
/*
* Blocks without live objects are removed from the
* block list and freed.
*/
#ifdef FIXED_HEAP
ms_free_block (block);
#else
*iter = block->next;
ms_free_block (block->block);
mono_sgen_free_internal (block, INTERNAL_MEM_MS_BLOCK_INFO);
#endif
--num_major_sections;
}
}
}
static int count_pinned_ref;
static int count_pinned_nonref;
static int count_nonpinned_ref;
static int count_nonpinned_nonref;
static void
count_nonpinned_callback (char *obj, size_t size, void *data)
{
MonoVTable *vtable = (MonoVTable*)LOAD_VTABLE (obj);
if (vtable->klass->has_references)
++count_nonpinned_ref;
else
++count_nonpinned_nonref;
}
static void
ms_sweep (void)
{
int i;
MSBlockInfo **iter;
/* statistics for evacuation */
int *slots_available = alloca (sizeof (int) * num_block_obj_sizes);
int *slots_used = alloca (sizeof (int) * num_block_obj_sizes);
int *num_blocks = alloca (sizeof (int) * num_block_obj_sizes);
for (i = 0; i < num_block_obj_sizes; ++i)
slots_available [i] = slots_used [i] = num_blocks [i] = 0;
/* clear all the free lists */
for (i = 0; i < MS_BLOCK_TYPE_MAX; ++i) {
MSBlockInfo **free_blocks = free_block_lists [i];
int j;
for (j = 0; j < num_block_obj_sizes; ++j)
free_blocks [j] = NULL;
}
/* traverse all blocks, free and zero unmarked objects */
iter = &all_blocks;
while (*iter) {
MSBlockInfo *block = *iter;
int count;
gboolean have_live = FALSE;
gboolean has_pinned;
int obj_index;
int obj_size_index;
obj_size_index = block->obj_size_index;
has_pinned = block->has_pinned;
block->has_pinned = block->pinned;
block->is_to_space = FALSE;
count = MS_BLOCK_FREE / block->obj_size;
block->free_list = NULL;
for (obj_index = 0; obj_index < count; ++obj_index) {
int word, bit;
void *obj = MS_BLOCK_OBJ (block, obj_index);
MS_CALC_MARK_BIT (word, bit, obj);
if (MS_MARK_BIT (block, word, bit)) {
DEBUG (9, g_assert (MS_OBJ_ALLOCED (obj, block)));
have_live = TRUE;
if (!has_pinned)
++slots_used [obj_size_index];
} else {
/* an unmarked object */
if (MS_OBJ_ALLOCED (obj, block)) {
binary_protocol_empty (obj, block->obj_size);
memset (obj, 0, block->obj_size);
}
*(void**)obj = block->free_list;
block->free_list = obj;
}
}
/* reset mark bits */
memset (block->mark_words, 0, sizeof (mword) * MS_NUM_MARK_WORDS);
/*
* FIXME: reverse free list so that it's in address
* order
*/
if (have_live) {
if (!has_pinned) {
++num_blocks [obj_size_index];
slots_available [obj_size_index] += count;
}
iter = &block->next;
/*
* If there are free slots in the block, add
* the block to the corresponding free list.
*/
if (block->free_list) {
MSBlockInfo **free_blocks = FREE_BLOCKS (block->pinned, block->has_references);
int index = MS_BLOCK_OBJ_SIZE_INDEX (block->obj_size);
block->next_free = free_blocks [index];
free_blocks [index] = block;
}
update_heap_boundaries_for_block (block);
} else {
/*
* Blocks without live objects are removed from the
* block list and freed.
*/
*iter = block->next;
#ifdef FIXED_HEAP
ms_free_block (block);
#else
ms_free_block (block->block);
mono_sgen_free_internal (block, INTERNAL_MEM_MS_BLOCK_INFO);
#endif
--num_major_sections;
}
}
for (i = 0; i < num_block_obj_sizes; ++i) {
float usage = (float)slots_used [i] / (float)slots_available [i];
if (num_blocks [i] > 5 && usage < evacuation_threshold) {
evacuate_block_obj_sizes [i] = TRUE;
/*
g_print ("slot size %d - %d of %d used\n",
block_obj_sizes [i], slots_used [i], slots_available [i]);
*/
} else {
evacuate_block_obj_sizes [i] = FALSE;
}
}
have_swept = TRUE;
}
