/**
* deactivate_page - deactivate a page
* @page: page to deactivate
*
* deactivate_page() moves @page to the inactive list if @page was on the active
* list and was not an unevictable page. This is done to accelerate the reclaim
* of @page.
*/
void deactivate_page(struct page *page)
{
if (PageLRU(page) && PageActive(page) && !PageUnevictable(page)) {
struct pagevec *pvec = &get_cpu_var(lru_deactivate_pvecs);
get_page(page);
if (!pagevec_add(pvec, page) || PageCompound(page))
pagevec_lru_move_fn(pvec, lru_deactivate_fn, NULL);
put_cpu_var(lru_deactivate_pvecs);
}
}
void activate_page(struct page *page)
{
if (PageLRU(page) && !PageActive(page) && !PageUnevictable(page)) {
struct pagevec *pvec = &get_cpu_var(activate_page_pvecs);
page_cache_get(page);
if (!pagevec_add(pvec, page))
pagevec_lru_move_fn(pvec, __activate_page, NULL);
put_cpu_var(activate_page_pvecs);
}
}
static void pagevec_move_tail_fn(struct page *page, struct lruvec *lruvec,
void *arg)
{
int *pgmoved = arg;
if (PageLRU(page) && !PageActive(page) && !PageUnevictable(page)) {
enum lru_list lru = page_lru_base_type(page);
list_move_tail(&page->lru, &lruvec->lists[lru]);
(*pgmoved)++;
}
}
static void pagevec_move_tail_fn(struct page *page, struct lruvec *lruvec,
void *arg)
{
int *pgmoved = arg;
if (PageLRU(page) && !PageUnevictable(page)) {
del_page_from_lru_list(page, lruvec, page_lru(page));
ClearPageActive(page);
add_page_to_lru_list_tail(page, lruvec, page_lru(page));
(*pgmoved)++;
}
}
void activate_page(struct page *page)
{
page = compound_head(page);
if (PageLRU(page) && !PageActive(page) && !PageUnevictable(page)) {
struct pagevec *pvec = &get_cpu_var(activate_page_pvecs);
get_page(page);
if (!pagevec_add(pvec, page) || PageCompound(page))
pagevec_lru_move_fn(pvec, __activate_page, NULL);
put_cpu_var(activate_page_pvecs);
}
}
static void pagevec_move_tail_fn(struct page *page, void *arg)
{
int *pgmoved = arg;
struct zone *zone = page_zone(page);
if (PageLRU(page) && !PageActive(page) && !PageUnevictable(page)) {
enum lru_list lru = page_lru_base_type(page);
list_move_tail(&page->lru, &zone->lru[lru].list);
mem_cgroup_rotate_reclaimable_page(page);
(*pgmoved)++;
}
}
/* used by __split_huge_page_refcount() */
void lru_add_page_tail(struct page *page, struct page *page_tail,
struct lruvec *lruvec, struct list_head *list)
{
int uninitialized_var(active);
enum lru_list lru;
const int file = 0;
VM_BUG_ON(!PageHead(page));
VM_BUG_ON(PageCompound(page_tail));
VM_BUG_ON(PageLRU(page_tail));
VM_BUG_ON(NR_CPUS != 1 &&
!spin_is_locked(&lruvec_zone(lruvec)->lru_lock));
if (!list)
SetPageLRU(page_tail);
if (page_evictable(page_tail)) {
if (PageActive(page)) {
SetPageActive(page_tail);
active = 1;
lru = LRU_ACTIVE_ANON;
} else {
active = 0;
lru = LRU_INACTIVE_ANON;
}
} else {
SetPageUnevictable(page_tail);
lru = LRU_UNEVICTABLE;
}
if (likely(PageLRU(page)))
list_add_tail(&page_tail->lru, &page->lru);
else if (list) {
/* page reclaim is reclaiming a huge page */
get_page(page_tail);
list_add_tail(&page_tail->lru, list);
} else {
struct list_head *list_head;
/*
* Head page has not yet been counted, as an hpage,
* so we must account for each subpage individually.
*
* Use the standard add function to put page_tail on the list,
* but then correct its position so they all end up in order.
*/
add_page_to_lru_list(page_tail, lruvec, lru);
list_head = page_tail->lru.prev;
list_move_tail(&page_tail->lru, list_head);
}
if (!PageUnevictable(page))
update_page_reclaim_stat(lruvec, file, active);
}
/**
* mark_page_lazyfree - make an anon page lazyfree
* @page: page to deactivate
*
* mark_page_lazyfree() moves @page to the inactive file list.
* This is done to accelerate the reclaim of @page.
*/
void mark_page_lazyfree(struct page *page)
{
if (PageLRU(page) && PageAnon(page) && PageSwapBacked(page) &&
!PageSwapCache(page) && !PageUnevictable(page)) {
struct pagevec *pvec = &get_cpu_var(lru_lazyfree_pvecs);
get_page(page);
if (!pagevec_add(pvec, page) || PageCompound(page))
pagevec_lru_move_fn(pvec, lru_lazyfree_fn, NULL);
put_cpu_var(lru_lazyfree_pvecs);
}
}
/*
* 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);
}
}
/*
* Writeback is about to end against a page which has been marked for immediate
* reclaim. If it still appears to be reclaimable, move it to the tail of the
* inactive list.
*/
void rotate_reclaimable_page(struct page *page)
{
if (!PageLocked(page) && !PageDirty(page) && !PageActive(page) &&
!PageUnevictable(page) && PageLRU(page)) {
struct pagevec *pvec;
unsigned long flags;
page_cache_get(page);
local_irq_save(flags);
pvec = &__get_cpu_var(lru_rotate_pvecs);
if (!pagevec_add(pvec, page))
pagevec_move_tail(pvec);
local_irq_restore(flags);
}
}
/*
* Writeback is about to end against a page which has been marked for immediate
* reclaim. If it still appears to be reclaimable, move it to the tail of the
* inactive list.
*/
void rotate_reclaimable_page(struct page *page)
{
if (!PageLocked(page) && !PageDirty(page) &&
!PageUnevictable(page) && PageLRU(page)) {
struct pagevec *pvec;
unsigned long flags;
get_page(page);
local_irq_save(flags);
pvec = this_cpu_ptr(&lru_rotate_pvecs);
if (!pagevec_add(pvec, page) || PageCompound(page))
pagevec_move_tail(pvec);
local_irq_restore(flags);
}
}
static void __activate_page(struct page *page, struct lruvec *lruvec,
void *arg)
{
if (PageLRU(page) && !PageActive(page) && !PageUnevictable(page)) {
int file = page_is_file_cache(page);
int lru = page_lru_base_type(page);
del_page_from_lru_list(page, lruvec, lru);
SetPageActive(page);
lru += LRU_ACTIVE;
add_page_to_lru_list(page, lruvec, lru);
__count_vm_event(PGACTIVATE);
update_page_reclaim_stat(lruvec, file, 1);
}
}
static void lru_deactivate_fn(struct page *page, struct lruvec *lruvec,
void *arg)
{
if (PageLRU(page) && PageActive(page) && !PageUnevictable(page)) {
int file = page_is_file_cache(page);
int lru = page_lru_base_type(page);
del_page_from_lru_list(page, lruvec, lru + LRU_ACTIVE);
ClearPageActive(page);
ClearPageReferenced(page);
add_page_to_lru_list(page, lruvec, lru);
__count_vm_event(PGDEACTIVATE);
update_page_reclaim_stat(lruvec, file, 0);
}
}
/*
* If the page can not be invalidated, it is moved to the
* inactive list to speed up its reclaim. It is moved to the
* head of the list, rather than the tail, to give the flusher
* threads some time to write it out, as this is much more
* effective than the single-page writeout from reclaim.
*
* If the page isn't page_mapped and dirty/writeback, the page
* could reclaim asap using PG_reclaim.
*
* 1. active, mapped page -> none
* 2. active, dirty/writeback page -> inactive, head, PG_reclaim
* 3. inactive, mapped page -> none
* 4. inactive, dirty/writeback page -> inactive, head, PG_reclaim
* 5. inactive, clean -> inactive, tail
* 6. Others -> none
*
* In 4, why it moves inactive's head, the VM expects the page would
* be write it out by flusher threads as this is much more effective
* than the single-page writeout from reclaim.
*/
static void lru_deactivate_fn(struct page *page, void *arg)
{
int lru, file;
bool active;
struct zone *zone = page_zone(page);
if (!PageLRU(page))
return;
if (PageUnevictable(page))
return;
/* Some processes are using the page */
if (page_mapped(page))
return;
active = PageActive(page);
file = page_is_file_cache(page);
lru = page_lru_base_type(page);
del_page_from_lru_list(zone, page, lru + active);
ClearPageActive(page);
ClearPageReferenced(page);
add_page_to_lru_list(zone, page, lru);
if (PageWriteback(page) || PageDirty(page)) {
/*
* PG_reclaim could be raced with end_page_writeback
* It can make readahead confusing. But race window
* is _really_ small and it's non-critical problem.
*/
SetPageReclaim(page);
} else {
struct lruvec *lruvec;
/*
* The page's writeback ends up during pagevec
* We moves tha page into tail of inactive.
*/
lruvec = mem_cgroup_lru_move_lists(zone, page, lru, lru);
list_move_tail(&page->lru, &lruvec->lists[lru]);
__count_vm_event(PGROTATED);
}
if (active)
__count_vm_event(PGDEACTIVATE);
update_page_reclaim_stat(zone, page, file, 0);
}
/*
* 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);
}
}
/**
* deactivate_page - forcefully deactivate a page
* @page: page to deactivate
*
* This function hints the VM that @page is a good reclaim candidate,
* for example if its invalidation fails due to the page being dirty
* or under writeback.
*/
void deactivate_page(struct page *page)
{
/*
* In a workload with many unevictable page such as mprotect, unevictable
* page deactivation for accelerating reclaim is pointless.
*/
if (PageUnevictable(page))
return;
if (likely(get_page_unless_zero(page))) {
struct pagevec *pvec = &get_cpu_var(lru_deactivate_pvecs);
if (!pagevec_add(pvec, page))
pagevec_lru_move_fn(pvec, lru_deactivate_fn, NULL);
put_cpu_var(lru_deactivate_pvecs);
}
}
static void __pagevec_lru_add_fn(struct page *page, struct lruvec *lruvec,
void *arg)
{
enum lru_list lru = (enum lru_list)arg;
int file = is_file_lru(lru);
int active = is_active_lru(lru);
VM_BUG_ON(PageActive(page));
VM_BUG_ON(PageUnevictable(page));
VM_BUG_ON(PageLRU(page));
SetPageLRU(page);
if (active)
SetPageActive(page);
add_page_to_lru_list(page, lruvec, lru);
update_page_reclaim_stat(lruvec, file, active);
}
/*
* FIXME: speed this up?
*/
void activate_page(struct page *page)
{
struct zone *zone = page_zone(page);
spin_lock_irq(&zone->lru_lock);
if (PageLRU(page) && !PageActive(page) && !PageUnevictable(page)) {
int file = page_is_file_cache(page);
int lru = page_lru_base_type(page);
del_page_from_lru_list(zone, page, lru);
SetPageActive(page);
lru += LRU_ACTIVE;
add_page_to_lru_list(zone, page, lru);
__count_vm_event(PGACTIVATE);
update_page_reclaim_stat(zone, page, file, 1);
}
spin_unlock_irq(&zone->lru_lock);
}
/*
* added by qijiwen.
* put the page on the lru directly
*/
void add_page_to_lru_list_cma(struct page *page, enum lru_list lru)
{
struct zone *zone = page_zone(page);
int file = is_file_lru(lru);
int active = is_active_lru(lru);
unsigned long flags = 0;
VM_BUG_ON(PageActive(page));
VM_BUG_ON(PageUnevictable(page));
VM_BUG_ON(PageLRU(page));
spin_lock_irqsave(&zone->lru_lock, flags);
SetPageLRU(page);
if (active)
SetPageActive(page);
update_page_reclaim_stat(zone, page, file, active);
add_page_to_lru_list(zone, page, lru);
spin_unlock_irqrestore(&zone->lru_lock, flags);
}
/*
* 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 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);
} else if (!PageReferenced(page)) {
SetPageReferenced(page);
}
}
/*
* FIXME: speed this up?
*/
void activate_page(struct page *page)
{
struct zone *zone = page_zone(page);
spin_lock_irq(&zone->lru_lock);
if (PageLRU(page) && !PageActive(page) && !PageUnevictable(page)) {
int file = page_is_file_cache(page);
int lru = LRU_BASE + file;
del_page_from_lru_list(zone, page, lru);
SetPageActive(page);
lru += LRU_ACTIVE;
add_page_to_lru_list(zone, page, lru);
__count_vm_event(PGACTIVATE);
mem_cgroup_move_lists(page, lru);
zone->recent_rotated[!!file]++;
zone->recent_scanned[!!file]++;
}
spin_unlock_irq(&zone->lru_lock);
}
/* used by __split_huge_page_refcount() */
void lru_add_page_tail(struct page *page, struct page *page_tail,
struct lruvec *lruvec, struct list_head *list)
{
const int file = 0;
VM_BUG_ON_PAGE(!PageHead(page), page);
VM_BUG_ON_PAGE(PageCompound(page_tail), page);
VM_BUG_ON_PAGE(PageLRU(page_tail), page);
VM_BUG_ON(NR_CPUS != 1 &&
!spin_is_locked(&lruvec_pgdat(lruvec)->lru_lock));
if (!list)
SetPageLRU(page_tail);
if (likely(PageLRU(page)))
list_add_tail(&page_tail->lru, &page->lru);
else if (list) {
/* page reclaim is reclaiming a huge page */
get_page(page_tail);
list_add_tail(&page_tail->lru, list);
} else {
struct list_head *list_head;
/*
* Head page has not yet been counted, as an hpage,
* so we must account for each subpage individually.
*
* Use the standard add function to put page_tail on the list,
* but then correct its position so they all end up in order.
*/
add_page_to_lru_list(page_tail, lruvec, page_lru(page_tail));
list_head = page_tail->lru.prev;
list_move_tail(&page_tail->lru, list_head);
}
if (!PageUnevictable(page))
update_page_reclaim_stat(lruvec, file, PageActive(page_tail));
}
static void lru_lazyfree_fn(struct page *page, struct lruvec *lruvec,
void *arg)
{
if (PageLRU(page) && PageAnon(page) && PageSwapBacked(page) &&
!PageSwapCache(page) && !PageUnevictable(page)) {
bool active = PageActive(page);
del_page_from_lru_list(page, lruvec,
LRU_INACTIVE_ANON + active);
ClearPageActive(page);
ClearPageReferenced(page);
/*
* lazyfree pages are clean anonymous pages. They have
* SwapBacked flag cleared to distinguish normal anonymous
* pages
*/
ClearPageSwapBacked(page);
add_page_to_lru_list(page, lruvec, LRU_INACTIVE_FILE);
__count_vm_events(PGLAZYFREE, hpage_nr_pages(page));
count_memcg_page_event(page, PGLAZYFREE);
update_page_reclaim_stat(lruvec, 1, 0);
}
}
/**
* ____pagevec_lru_add:将pvec缓存的页加入到zone的lru类型的LRU链表中去
* @ prev:页临时缓存
* @ lru: 页加入到区中LRU链表的类型
*/
void ____pagevec_lru_add(struct pagevec *pvec, enum lru_list lru)
{
int i;
struct zone *zone = NULL;
VM_BUG_ON(is_unevictable_lru(lru));
for (i = 0; i < pagevec_count(pvec); i++) {
struct page *page = pvec->pages[i];
struct zone *pagezone = page_zone(page);
int file;
int active;
if (pagezone != zone) {
if (zone)
spin_unlock_irq(&zone->lru_lock);
zone = pagezone;
spin_lock_irq(&zone->lru_lock);
}
/*页框的属性不能是ACTIVE LRU UNEVICT*/
VM_BUG_ON(PageActive(page));
VM_BUG_ON(PageUnevictable(page));
VM_BUG_ON(PageLRU(page));
SetPageLRU(page);
active = is_active_lru(lru);
file = is_file_lru(lru);
if (active)
SetPageActive(page);
update_page_reclaim_stat(zone, page, file, active);
add_page_to_lru_list(zone, page, lru);
}
if (zone)
spin_unlock_irq(&zone->lru_lock);
release_pages(pvec->pages, pvec->nr, pvec->cold);
pagevec_reinit(pvec);
}
/**
* lru_cache_add - add a page to a page list
* @page: the page to be added to the LRU.
*/
void lru_cache_add(struct page *page)
{
VM_BUG_ON(PageActive(page) && PageUnevictable(page));
VM_BUG_ON(PageLRU(page));
__lru_cache_add(page);
}
static unsigned int shrink_pages(struct mm_struct *mm, struct zone **zone_id_0,
struct list_head *zone0_page_list,
struct zone **zone_id_1,
struct list_head *zone1_page_list,
unsigned int num_to_scan)
{
unsigned long addr;
unsigned int isolate_pages_countter = 0;
struct vm_area_struct *vma = mm->mmap;
while (vma != NULL) {
for (addr = vma->vm_start; addr < vma->vm_end;
addr += PAGE_SIZE) {
struct page *page;
/*get the page address from virtual memory address */
page = follow_page(vma, addr, FOLL_GET);
if (page && !IS_ERR(page)) {
put_page(page);
/* only moveable, anonymous and not dirty pages can be swapped */
if ((!PageUnevictable(page))
&& (!PageDirty(page)) && ((PageAnon(page)))
&& (0 == page_is_file_cache(page))) {
switch (page_zone_id(page)) {
case 0:
if (!isolate_lru_page(page)) {
/* isolate page from LRU and add to temp list */
*zone_id_0 =
page_zone(page);
/*create new page list, it will be used in shrink_page_list */
spin_lock_irq(&(*zone_id_0)->lru_lock);
list_add_tail(&page->lru, zone0_page_list);
spin_unlock_irq(&(*zone_id_0)->lru_lock);
isolate_pages_countter++;
}
break;
case 1:
if (!isolate_lru_page(page)) {
/* isolate page from LRU and add to temp list */
*zone_id_1 =
page_zone(page);
/*create new page list, it will be used in shrink_page_list */
spin_lock_irq(&(*zone_id_1)->lru_lock);
list_add_tail(&page->lru, zone1_page_list);
spin_unlock_irq(&(*zone_id_1)->lru_lock);
isolate_pages_countter++;
}
break;
default:
break;
}
}
}
if (isolate_pages_countter >= num_to_scan) {
return isolate_pages_countter;
}
}
vma = vma->vm_next;
}
return isolate_pages_countter;
}
