Function rte_bitmap_init

dpdk/lib/eal/include/rte_bitmap.h:169–203

* Bitmap initialization * * @param n_bits * Number of pre-allocated bits in array2. * @param mem * Base address of array1 and array2. * @param mem_size * Minimum expected size of bitmap. * @return * Handle to bitmap instance. */

 *   Handle to bitmap instance.
 */
static inline struct rte_bitmap *
rte_bitmap_init(uint32_t n_bits, uint8_t *mem, uint32_t mem_size)
{
	struct rte_bitmap *bmp;
	uint32_t array1_byte_offset, array1_slabs, array2_byte_offset, array2_slabs;
	uint32_t size;

	/* Check input arguments */
	if (n_bits == 0) {
		return NULL;
	}

	if ((mem == NULL) || (((uintptr_t) mem) & RTE_CACHE_LINE_MASK)) {
		return NULL;
	}

	size = __rte_bitmap_get_memory_footprint(n_bits,
		&array1_byte_offset, &array1_slabs,
		&array2_byte_offset, &array2_slabs);
	if (size > mem_size)
		return NULL;

	/* Setup bitmap */
	memset(mem, 0, size);
	bmp = (struct rte_bitmap *) mem;

	bmp->array1 = (uint64_t *) &mem[array1_byte_offset];
	bmp->array1_size = array1_slabs;
	bmp->array2 = (uint64_t *) &mem[array2_byte_offset];
	bmp->array2_size = array2_slabs;

	__rte_bitmap_scan_init(bmp);

	return bmp;
}

/**
 * Bitmap clear slab overhead bits.