void
mem_buddy_test() {
as_mem_buddy_t *b = buddy_new(4);
unsigned x = buddy_alloc(b, 4);
buddy_alloc(b, 8);
buddy_alloc(b, 2);
buddy_free(b, x);
buddy_print(b);
buddy_destroy(b);
}
int main()
{
struct Node * tempNode1, *tempNode2, *tempNode3;
int size = 10;
struct HeadNode * tempHead = buddy_new(size);
if (tempHead!=NULL)
{
//注意申请的空间最大不是2^k, 而是2^k - 1
tempNode1 = buddy_alloc(tempHead,size,511);
buddy_print(tempHead, size);
tempNode2 = buddy_alloc(tempHead,size,10);
buddy_print(tempHead, size);
tempNode3 = buddy_alloc(tempHead,size,10);
buddy_print(tempHead, size);
buddy_combine(tempHead, size, tempNode3);
buddy_print(tempHead, size);
buddy_combine(tempHead, size, tempNode2);
buddy_print(tempHead, size);
buddy_combine(tempHead, size, tempNode1);
buddy_print(tempHead, size);
}
buddy_free(tempHead);
getchar();
return 0;
}
void init_palloc()
{
kprintf("Initializing page frame allocator\n");
// Initialize bucket list
int j, k;
for (j = 0; j < PALLOC_BUCKET_COUNT; j++) {
buckets[j].bucket_tag = j;
buckets[j].total_pages = 0;
buckets[j].avail_pages = 0;
for (k = 0; k < PALLOC_ORDER_COUNT; k++) {
buckets[j].buddies[k].value = 0;
}
spin_init(&buckets[j].lock);
}
// Calculate total number of nodes - 1 page needs 1 node
ulong node_count = hal->paddr_space_end / PAGE_SIZE;
ulong node_size = node_count * sizeof(struct palloc_node);
kprintf("\tPalloc node size: %d KB, pages: %d\n", node_size / 1024, node_size / PAGE_SIZE);
// Allocate and reserve memory
nodes = (struct palloc_node *)hal->free_mem_start_addr;
reserve_pfndb_mem(hal->free_mem_start_addr, node_size);
hal->free_mem_start_addr += node_size;
// Initialize all nodes
ulong i;
for (i = 0; i < node_count; i++) {
nodes[i].avail = 0;
nodes[i].tag = PALLOC_DUMMY_BUCKET;
}
// Go through PFN database to construct tags array
struct pfndb_entry *entry = get_pfn_entry_by_paddr(0);
int cur_tag = entry->tag;
int recording = 0;
ulong cur_bucket_start = 0;
for (i = 0; i < hal->paddr_space_end; i += PAGE_SIZE) {
entry = get_pfn_entry_by_paddr(i);
// End of a bucket
if (
recording &&
(!entry->usable || entry->inuse || cur_tag != entry->tag)
) {
init_bucket(cur_bucket_start, i - cur_bucket_start, cur_tag);
recording = 0;
}
// Start of a bucket
else if (
!recording &&
(entry->usable && !entry->inuse && entry->tag != PALLOC_DUMMY_BUCKET)
) {
cur_bucket_start = i;
cur_tag = entry->tag;
recording = 1;
}
}
// Take care of the last bucket
if (recording) {
init_bucket(cur_bucket_start, hal->paddr_space_end - cur_bucket_start, cur_tag);
}
// Print the buddy
buddy_print();
}
