Function malloc_elem_free

dpdk/lib/eal/common/malloc_elem.c:569–605

* free a malloc_elem block by adding it to the free list. If the * blocks either immediately before or immediately after newly freed block * are also free, the blocks are merged together. */

 * are also free, the blocks are merged together.
 */
struct malloc_elem *
malloc_elem_free(struct malloc_elem *elem)
{
	void *ptr;
	size_t data_len;

	ptr = RTE_PTR_ADD(elem, MALLOC_ELEM_HEADER_LEN);
	data_len = elem->size - MALLOC_ELEM_OVERHEAD;

	/*
	 * Consider the element clean for the purposes of joining.
	 * If both neighbors are clean or non-existent,
	 * the joint element will be clean,
	 * which means the memory should be cleared.
	 * There is no need to clear the memory if the joint element is dirty.
	 */
	elem->dirty = false;
	elem = malloc_elem_join_adjacent_free(elem);

	malloc_elem_free_list_insert(elem);

	elem->pad = 0;

	/* decrease heap's count of allocated elements */
	elem->heap->alloc_count--;

#ifndef RTE_MALLOC_DEBUG
	/* Normally clear the memory when needed. */
	if (!elem->dirty)
		memset(ptr, 0, data_len);
#else
	/* Always poison the memory in debug mode. */
	memset(ptr, MALLOC_POISON, data_len);
#endif

	return elem;
}

/* assume all checks were already done */
void