Speeding up procedure for getting start of a heap block's data space for one-chunked blocks, removing general blocks support from the procedure.

- heap area is aligned on heap chunk size;
 - mem_heap_get_block_start is renamed to mem_heap_get_chunked_block_start,
   now this interface is applicable only to one-chunked blocks,
   and is significantly faster - instead of iterating list of heap blocks
   to find block header, it just aligns value of pointer to heap chunk size.

JerryScript-DCO-1.0-Signed-off-by: Ruben Ayrapetyan r.ayrapetyan@samsung.com
This commit is contained in:
Ruben Ayrapetyan 2015-05-14 22:15:45 +03:00
parent 253e172127
commit 82f9afcde9
4 changed files with 77 additions and 39 deletions

View File

@ -30,7 +30,8 @@
/** /**
* Area for heap * Area for heap
*/ */
static uint8_t mem_heap_area[ MEM_HEAP_AREA_SIZE ] __attribute__ ((aligned (MEM_ALIGNMENT))); static uint8_t mem_heap_area[ MEM_HEAP_AREA_SIZE ] __attribute__ ((aligned (JERRY_MAX (MEM_ALIGNMENT,
MEM_HEAP_CHUNK_SIZE))));
/** /**
* The 'try to give memory back' callback * The 'try to give memory back' callback

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@ -396,6 +396,9 @@ mem_is_block_free (const mem_block_header_t *block_header_p) /**< block header *
/** /**
* Startup initialization of heap * Startup initialization of heap
*
* Note:
* heap start and size should be aligned on MEM_HEAP_CHUNK_SIZE
*/ */
void void
mem_heap_init (uint8_t *heap_start, /**< first address of heap space */ mem_heap_init (uint8_t *heap_start, /**< first address of heap space */
@ -403,8 +406,12 @@ mem_heap_init (uint8_t *heap_start, /**< first address of heap space */
{ {
JERRY_ASSERT (heap_start != NULL); JERRY_ASSERT (heap_start != NULL);
JERRY_ASSERT (heap_size != 0); JERRY_ASSERT (heap_size != 0);
JERRY_ASSERT (heap_size % MEM_HEAP_CHUNK_SIZE == 0);
JERRY_STATIC_ASSERT ((MEM_HEAP_CHUNK_SIZE & (MEM_HEAP_CHUNK_SIZE - 1u)) == 0);
JERRY_ASSERT ((uintptr_t) heap_start % MEM_ALIGNMENT == 0); JERRY_ASSERT ((uintptr_t) heap_start % MEM_ALIGNMENT == 0);
JERRY_ASSERT ((uintptr_t) heap_start % MEM_HEAP_CHUNK_SIZE == 0);
JERRY_ASSERT (heap_size % MEM_HEAP_CHUNK_SIZE == 0);
JERRY_ASSERT (heap_size <= (1u << MEM_HEAP_OFFSET_LOG)); JERRY_ASSERT (heap_size <= (1u << MEM_HEAP_OFFSET_LOG));
mem_heap.heap_start = heap_start; mem_heap.heap_start = heap_start;
@ -800,6 +807,7 @@ mem_heap_free_block (void *ptr) /**< pointer to beginning of data space of the b
/* marking the block free */ /* marking the block free */
block_p->allocated_bytes = 0; block_p->allocated_bytes = 0;
block_p->length_type = mem_block_length_type_t::GENERAL;
if (next_block_p != NULL) if (next_block_p != NULL)
{ {
@ -866,12 +874,12 @@ mem_heap_free_block (void *ptr) /**< pointer to beginning of data space of the b
} /* mem_heap_free_block */ } /* mem_heap_free_block */
/** /**
* Find beginning of user data in a block from pointer, * Find beginning of user data in a one-chunked block from pointer,
* pointing into it, i.e. into [block_data_space_start; block_data_space_end) range. * pointing into it, i.e. into [block_data_space_start; block_data_space_end) range.
* *
* Note: * Note:
* Pointer must point to the memory region which was previously allocated * Pointer must point to the one-chunked memory region which was previously allocated
* with mem_heap_alloc_block and is currently valid. * with mem_heap_alloc_chunked_block and is currently valid.
* *
* Note: * Note:
* The interface should only be used for determining where the user space of heap-allocated block begins. * The interface should only be used for determining where the user space of heap-allocated block begins.
@ -880,49 +888,59 @@ mem_heap_free_block (void *ptr) /**< pointer to beginning of data space of the b
* @return beginning of user data space of block identified by the pointer * @return beginning of user data space of block identified by the pointer
*/ */
void* void*
mem_heap_get_block_start (void *ptr) /**< pointer into a block */ mem_heap_get_chunked_block_start (void *ptr) /**< pointer into a block */
{ {
mem_check_heap (); JERRY_STATIC_ASSERT ((MEM_HEAP_CHUNK_SIZE & (MEM_HEAP_CHUNK_SIZE - 1u)) == 0);
JERRY_ASSERT (((uintptr_t) mem_heap.heap_start % MEM_HEAP_CHUNK_SIZE) == 0);
/*
* PERF: consider introducing bitmap of block beginnings
*/
JERRY_ASSERT (mem_heap.heap_start <= ptr JERRY_ASSERT (mem_heap.heap_start <= ptr
&& ptr < mem_heap.heap_start + mem_heap.heap_size); && ptr < mem_heap.heap_start + mem_heap.heap_size);
const mem_block_header_t *block_p = mem_heap.first_block_p; uintptr_t uintptr = (uintptr_t) ptr;
uintptr_t uintptr_chunk_aligned = JERRY_ALIGNDOWN (uintptr, MEM_HEAP_CHUNK_SIZE);
JERRY_ASSERT (uintptr > uintptr_chunk_aligned);
mem_block_header_t *block_p = (mem_block_header_t *) uintptr_chunk_aligned;
JERRY_ASSERT (block_p->length_type == mem_block_length_type_t::ONE_CHUNKED);
#ifndef JERRY_NDEBUG
const mem_block_header_t *block_iter_p = mem_heap.first_block_p;
bool is_found = false;
/* searching for corresponding block */ /* searching for corresponding block */
while (block_p != NULL) while (block_iter_p != NULL)
{ {
VALGRIND_DEFINED_STRUCT (block_p); VALGRIND_DEFINED_STRUCT (block_iter_p);
const mem_block_header_t *next_block_p = mem_get_next_block_by_direction (block_p, const mem_block_header_t *next_block_p = mem_get_next_block_by_direction (block_iter_p,
MEM_DIRECTION_NEXT); MEM_DIRECTION_NEXT);
bool is_found = (ptr > block_p is_found = (ptr > block_iter_p
&& (ptr < next_block_p && (ptr < next_block_p
|| next_block_p == NULL)); || next_block_p == NULL));
if (is_found) if (is_found)
{ {
JERRY_ASSERT (!mem_is_block_free (block_p)); JERRY_ASSERT (!mem_is_block_free (block_iter_p));
JERRY_ASSERT (block_p + 1 <= ptr); JERRY_ASSERT (block_iter_p + 1 <= ptr);
JERRY_ASSERT (ptr < ((uint8_t*) (block_p + 1) + block_p->allocated_bytes)); JERRY_ASSERT (ptr < ((uint8_t*) (block_iter_p + 1) + block_iter_p->allocated_bytes));
} }
VALGRIND_NOACCESS_STRUCT (block_p); VALGRIND_NOACCESS_STRUCT (block_iter_p);
if (is_found) if (is_found)
{ {
break;
}
block_iter_p = next_block_p;
}
JERRY_ASSERT (is_found && block_p == block_iter_p);
#endif /* !JERRY_NDEBUG */
return (void*) (block_p + 1); return (void*) (block_p + 1);
} } /* mem_heap_get_chunked_block_start */
block_p = next_block_p;
}
JERRY_UNREACHABLE ();
} /* mem_heap_get_block_start */
/** /**
* Get size of one-chunked block data space * Get size of one-chunked block data space

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@ -44,7 +44,7 @@ extern void mem_heap_finalize (void);
extern void* mem_heap_alloc_block (size_t size_in_bytes, mem_heap_alloc_term_t alloc_term); extern void* mem_heap_alloc_block (size_t size_in_bytes, mem_heap_alloc_term_t alloc_term);
extern void* mem_heap_alloc_chunked_block (mem_heap_alloc_term_t alloc_term); extern void* mem_heap_alloc_chunked_block (mem_heap_alloc_term_t alloc_term);
extern void mem_heap_free_block (void *ptr); extern void mem_heap_free_block (void *ptr);
extern void* mem_heap_get_block_start (void *ptr); extern void* mem_heap_get_chunked_block_start (void *ptr);
extern size_t mem_heap_get_chunked_block_data_size (void); extern size_t mem_heap_get_chunked_block_data_size (void);
extern size_t __attr_pure___ mem_heap_recommend_allocation_size (size_t minimum_allocation_size); extern size_t __attr_pure___ mem_heap_recommend_allocation_size (size_t minimum_allocation_size);
extern void mem_heap_print (bool dump_block_headers, bool dump_block_data, bool dump_stats); extern void mem_heap_print (bool dump_block_headers, bool dump_block_data, bool dump_stats);

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@ -39,6 +39,7 @@ extern "C"
uint8_t *ptrs[test_sub_iters]; uint8_t *ptrs[test_sub_iters];
size_t sizes[test_sub_iters]; size_t sizes[test_sub_iters];
bool is_one_chunked[test_sub_iters];
static void static void
test_heap_give_some_memory_back (mem_try_give_memory_back_severity_t severity) test_heap_give_some_memory_back (mem_try_give_memory_back_severity_t severity)
@ -82,12 +83,13 @@ test_heap_give_some_memory_back (mem_try_give_memory_back_severity_t severity)
} }
} /* test_heap_give_some_memory_back */ } /* test_heap_give_some_memory_back */
uint8_t test_native_heap[test_heap_size] __attribute__ ((aligned (JERRY_MAX (MEM_ALIGNMENT,
MEM_HEAP_CHUNK_SIZE))));
int int
main (int __attr_unused___ argc, main (int __attr_unused___ argc,
char __attr_unused___ **argv) char __attr_unused___ **argv)
{ {
uint8_t test_native_heap[test_heap_size];
mem_heap_init (test_native_heap, sizeof (test_native_heap)); mem_heap_init (test_native_heap, sizeof (test_native_heap));
srand ((unsigned int) time (NULL)); srand ((unsigned int) time (NULL));
@ -102,18 +104,32 @@ main (int __attr_unused___ argc,
for (uint32_t i = 0; i < test_iters; i++) for (uint32_t i = 0; i < test_iters; i++)
{ {
for (uint32_t j = 0; j < test_sub_iters; j++) for (uint32_t j = 0; j < test_sub_iters; j++)
{
if (rand () % 2)
{ {
size_t size = (size_t) rand () % test_threshold_block_size; size_t size = (size_t) rand () % test_threshold_block_size;
ptrs[j] = (uint8_t*) mem_heap_alloc_block (size, ptrs[j] = (uint8_t*) mem_heap_alloc_block (size,
(rand () % 2) ? (rand () % 2) ?
MEM_HEAP_ALLOC_LONG_TERM : MEM_HEAP_ALLOC_SHORT_TERM); MEM_HEAP_ALLOC_LONG_TERM : MEM_HEAP_ALLOC_SHORT_TERM);
sizes[j] = size; sizes[j] = size;
is_one_chunked[j] = false;
}
else
{
ptrs[j] = (uint8_t*) mem_heap_alloc_chunked_block ((rand () % 2) ?
MEM_HEAP_ALLOC_LONG_TERM : MEM_HEAP_ALLOC_SHORT_TERM);
sizes[j] = mem_heap_get_chunked_block_data_size ();
is_one_chunked[j] = true;
}
JERRY_ASSERT (size == 0 || ptrs[j] != NULL); JERRY_ASSERT (sizes[j] == 0 || ptrs[j] != NULL);
memset (ptrs[j], 0, sizes[j]); memset (ptrs[j], 0, sizes[j]);
JERRY_ASSERT (ptrs[j] == NULL if (is_one_chunked[j])
|| mem_heap_get_block_start (ptrs[j] + (size_t) rand () % sizes[j]) == ptrs[j]); {
JERRY_ASSERT (ptrs[j] != NULL
&& mem_heap_get_chunked_block_start (ptrs[j] + (size_t) rand () % sizes[j]) == ptrs[j]);
}
} }
// mem_heap_print (true); // mem_heap_print (true);
@ -127,8 +143,11 @@ main (int __attr_unused___ argc,
JERRY_ASSERT (ptrs[j][k] == 0); JERRY_ASSERT (ptrs[j][k] == 0);
} }
if (is_one_chunked[j])
{
JERRY_ASSERT (sizes[j] == 0 JERRY_ASSERT (sizes[j] == 0
|| mem_heap_get_block_start (ptrs[j] + (size_t) rand () % sizes[j]) == ptrs[j]); || mem_heap_get_chunked_block_start (ptrs[j] + (size_t) rand () % sizes[j]) == ptrs[j]);
}
mem_heap_free_block (ptrs[j]); mem_heap_free_block (ptrs[j]);