/*
* Batched page_cache_release(). Decrement the reference count on all the
* passed pages. If it fell to zero then remove the page from the LRU and
* free it.
*
* Avoid taking zone->lru_lock if possible, but if it is taken, retain it
* for the remainder of the operation.
*
* The locking in this function is against shrink_inactive_list(): we recheck
* the page count inside the lock to see whether shrink_inactive_list()
* grabbed the page via the LRU. If it did, give up: shrink_inactive_list()
* will free it.
*/
void release_pages(struct page **pages, int nr, int cold)
{
int i;
LIST_HEAD(pages_to_free);
struct zone *zone = NULL;
struct lruvec *lruvec;
unsigned long uninitialized_var(flags);
for (i = 0; i < nr; i++) {
struct page *page = pages[i];
if (unlikely(PageCompound(page))) {
if (zone) {
spin_unlock_irqrestore(&zone->lru_lock, flags);
zone = NULL;
}
put_compound_page(page);
continue;
}
if (!put_page_testzero(page))
continue;
if (PageLRU(page)) {
struct zone *pagezone = page_zone(page);
if (pagezone != zone) {
if (zone)
spin_unlock_irqrestore(&zone->lru_lock,
flags);
zone = pagezone;
spin_lock_irqsave(&zone->lru_lock, flags);
}
lruvec = mem_cgroup_page_lruvec(page, zone);
VM_BUG_ON(!PageLRU(page));
__ClearPageLRU(page);
del_page_from_lru_list(page, lruvec, page_off_lru(page));
}
/* Clear Active bit in case of parallel mark_page_accessed */
ClearPageActive(page);
list_add(&page->lru, &pages_to_free);
}
if (zone)
spin_unlock_irqrestore(&zone->lru_lock, flags);
free_hot_cold_page_list(&pages_to_free, cold);
}
/*
* Batched page_cache_release(). Decrement the reference count on all the
* passed pages. If it fell to zero then remove the page from the LRU and
* free it.
*
* Avoid taking zone->lru_lock if possible, but if it is taken, retain it
* for the remainder of the operation.
*
* The locking in this function is against shrink_inactive_list(): we recheck
* the page count inside the lock to see whether shrink_inactive_list()
* grabbed the page via the LRU. If it did, give up: shrink_inactive_list()
* will free it.
*/
void release_pages(struct page **pages, int nr, int cold)
{
int i;
LIST_HEAD(pages_to_free);
struct zone *zone = NULL;
unsigned long uninitialized_var(flags);
for (i = 0; i < nr; i++) {
struct page *page = pages[i];
if (unlikely(PageCompound(page))) {
if (zone) {
spin_unlock_irqrestore(&zone->lru_lock, flags);
zone = NULL;
}
put_compound_page(page);
continue;
}
if (!put_page_testzero(page))
continue;
if (PageLRU(page)) {
struct zone *pagezone = page_zone(page);
if (pagezone != zone) {
if (zone)
spin_unlock_irqrestore(&zone->lru_lock,
flags);
zone = pagezone;
spin_lock_irqsave(&zone->lru_lock, flags);
}
VM_BUG_ON(!PageLRU(page));
__ClearPageLRU(page);
del_page_from_lru_list(zone, page, page_off_lru(page));
}
list_add(&page->lru, &pages_to_free);
}
if (zone)
spin_unlock_irqrestore(&zone->lru_lock, flags);
free_hot_cold_page_list(&pages_to_free, cold);
}
/**
* release_pages - batched page_cache_release()
* @pages: array of pages to release
* @nr: number of pages
* @cold: whether the pages are cache cold
*
* Decrement the reference count on all the pages in @pages. If it
* fell to zero, remove the page from the LRU and free it.
*/
void release_pages(struct page **pages, int nr, bool cold)
{
int i;
LIST_HEAD(pages_to_free);
struct zone *zone = NULL;
struct lruvec *lruvec;
unsigned long uninitialized_var(flags);
unsigned int uninitialized_var(lock_batch);
for (i = 0; i < nr; i++) {
struct page *page = pages[i];
if (unlikely(PageCompound(page))) {
if (zone) {
spin_unlock_irqrestore(&zone->lru_lock, flags);
zone = NULL;
}
put_compound_page(page);
continue;
}
/*
* Make sure the IRQ-safe lock-holding time does not get
* excessive with a continuous string of pages from the
* same zone. The lock is held only if zone != NULL.
*/
if (zone && ++lock_batch == SWAP_CLUSTER_MAX) {
spin_unlock_irqrestore(&zone->lru_lock, flags);
zone = NULL;
}
if (!put_page_testzero(page))
continue;
if (PageLRU(page)) {
struct zone *pagezone = page_zone(page);
if (pagezone != zone) {
if (zone)
spin_unlock_irqrestore(&zone->lru_lock,
flags);
lock_batch = 0;
zone = pagezone;
spin_lock_irqsave(&zone->lru_lock, flags);
}
lruvec = mem_cgroup_page_lruvec(page, zone);
VM_BUG_ON_PAGE(!PageLRU(page), page);
__ClearPageLRU(page);
del_page_from_lru_list(page, lruvec, page_off_lru(page));
}
/* Clear Active bit in case of parallel mark_page_accessed */
__ClearPageActive(page);
list_add(&page->lru, &pages_to_free);
}
if (zone)
spin_unlock_irqrestore(&zone->lru_lock, flags);
mem_cgroup_uncharge_list(&pages_to_free);
free_hot_cold_page_list(&pages_to_free, cold);
}
