/*
* Mark a page as having seen activity.
*
* inactive,unreferenced -> inactive,referenced
* inactive,referenced -> active,unreferenced
* active,unreferenced -> active,referenced
*
* When a newly allocated page is not yet visible, so safe for non-atomic ops,
* __SetPageReferenced(page) may be substituted for mark_page_accessed(page).
*/
void mark_page_accessed(struct page *page)
{
page = compound_head(page);
if (!PageActive(page) && !PageUnevictable(page) &&
PageReferenced(page)) {
/*
* If the page is on the LRU, queue it for activation via
* activate_page_pvecs. Otherwise, assume the page is on a
* pagevec, mark it active and it'll be moved to the active
* LRU on the next drain.
*/
if (PageLRU(page))
activate_page(page);
else
__lru_cache_activate_page(page);
ClearPageReferenced(page);
if (page_is_file_cache(page))
workingset_activation(page);
} else if (!PageReferenced(page)) {
SetPageReferenced(page);
}
if (page_is_idle(page))
clear_page_idle(page);
}
/*
* This moves pages from the active list to
* the inactive list.
*
* We move them the other way when we see the
* reference bit on the page.
*/
static void refill_inactive(int nr_pages)
{
struct list_head * entry;
spin_lock(&pagemap_lru_lock);
entry = active_list.prev;
while (nr_pages && entry != &active_list) {
struct page * page;
page = list_entry(entry, struct page, lru);
entry = entry->prev;
if (PageTestandClearReferenced(page)) {
list_del(&page->lru);
list_add(&page->lru, &active_list);
continue;
}
nr_pages--;
del_page_from_active_list(page);
add_page_to_inactive_list(page);
SetPageReferenced(page);
}
spin_unlock(&pagemap_lru_lock);
}
/*
* This moves pages from the active list to
* the inactive list.
*
* We move them the other way when we see the
* reference bit on the page.
*/
static void refill_inactive(int nr_pages, zone_t * classzone)
{
struct list_head * entry;
unsigned long ratio;
ratio = (unsigned long) nr_pages * classzone->nr_active_pages / (((unsigned long) classzone->nr_inactive_pages * vm_lru_balance_ratio) + 1);
entry = active_list.prev;
while (ratio && entry != &active_list) {
struct page * page;
page = list_entry(entry, struct page, lru);
entry = entry->prev;
if (PageTestandClearReferenced(page)) {
list_del(&page->lru);
list_add(&page->lru, &active_list);
continue;
}
ratio--;
del_page_from_active_list(page);
add_page_to_inactive_list(page);
SetPageReferenced(page);
}
if (entry != &active_list) {
list_del(&active_list);
list_add(&active_list, entry);
}
}
/*
* Mark a page as having seen activity.
*
* inactive,unreferenced -> inactive,referenced
* inactive,referenced -> active,unreferenced
* active,unreferenced -> active,referenced
*/
void fastcall mark_page_accessed(struct page *page)
{
if (!PageActive(page) && PageReferenced(page) && PageLRU(page)) {
activate_page(page);
ClearPageReferenced(page);
} else if (!PageReferenced(page)) {
SetPageReferenced(page);
}
}
/*
* Mark a page as having seen activity.
*
* inactive,unreferenced -> inactive,referenced
* inactive,referenced -> active,unreferenced
* active,unreferenced -> active,referenced
*/
void mark_page_accessed(struct page *page)
{
if (!PageActive(page) && !PageUnevictable(page) &&
PageReferenced(page) && PageLRU(page)) {
activate_page(page);
ClearPageReferenced(page);
} else if (!PageReferenced(page)) {
SetPageReferenced(page);
}
}
/*
* mark_page_accessed：页访问的状态变化
* 非活动页的第一次访问状态变化: inactive,unreferenced -> inactive,referenced
* 非活动页的第二次访问状态变化: inactive,referenced -> active,unreferenced
* 活动页的第一次访问状态变化: active,unreferenced -> active,referenced
*/
void mark_page_accessed(struct page *page)
{
if (!PageActive(page) && !PageUnevictable(page) &&
PageReferenced(page) && PageLRU(page)) {
/* 非活动页的第二次访问:
* 将会使页从非活动链表移动到
* 活动链表,并且设置unreference*/
activate_page(page);
ClearPageReferenced(page);
} else if (!PageReferenced(page)) {
/*第一次访问非活动page或者访问活动页时只设置PG_reference*/
SetPageReferenced(page);
}
}
/*
* Mark a page as having seen activity.
*
* inactive,unreferenced -> inactive,referenced
* inactive,referenced -> active,unreferenced
* active,unreferenced -> active,referenced
*/
void mark_page_accessed(struct page *page)
{
if (!PageActive(page) && !PageUnevictable(page) &&
PageReferenced(page)) {
if (PageLRU(page))
activate_page(page);
else if (PageIONBacked(page))
SetPageActive(page);
else
return;
ClearPageReferenced(page);
} else if (!PageReferenced(page)) {
SetPageReferenced(page);
if (PageIONBacked(page) && PageActive(page))
ion_activate_page(page);
}
}
