aboutsummaryrefslogtreecommitdiff
path: root/mm/swap.c
diff options
context:
space:
mode:
Diffstat (limited to 'mm/swap.c')
-rw-r--r--mm/swap.c688
1 files changed, 514 insertions, 174 deletions
diff --git a/mm/swap.c b/mm/swap.c
index fff1ff7fb9a..9e8e3472248 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -30,13 +30,17 @@
#include <linux/backing-dev.h>
#include <linux/memcontrol.h>
#include <linux/gfp.h>
+#include <linux/uio.h>
#include "internal.h"
+#define CREATE_TRACE_POINTS
+#include <trace/events/pagemap.h>
+
/* How many pages do we try to swap or page in/out together? */
int page_cluster;
-static DEFINE_PER_CPU(struct pagevec[NR_LRU_LISTS], lru_add_pvecs);
+static DEFINE_PER_CPU(struct pagevec, lru_add_pvec);
static DEFINE_PER_CPU(struct pagevec, lru_rotate_pvecs);
static DEFINE_PER_CPU(struct pagevec, lru_deactivate_pvecs);
@@ -47,13 +51,15 @@ static DEFINE_PER_CPU(struct pagevec, lru_deactivate_pvecs);
static void __page_cache_release(struct page *page)
{
if (PageLRU(page)) {
- unsigned long flags;
struct zone *zone = page_zone(page);
+ struct lruvec *lruvec;
+ unsigned long flags;
spin_lock_irqsave(&zone->lru_lock, flags);
- VM_BUG_ON(!PageLRU(page));
+ lruvec = mem_cgroup_page_lruvec(page, zone);
+ VM_BUG_ON_PAGE(!PageLRU(page), page);
__ClearPageLRU(page);
- del_page_from_lru_list(zone, page, page_off_lru(page));
+ del_page_from_lru_list(page, lruvec, page_off_lru(page));
spin_unlock_irqrestore(&zone->lru_lock, flags);
}
}
@@ -61,7 +67,7 @@ static void __page_cache_release(struct page *page)
static void __put_single_page(struct page *page)
{
__page_cache_release(page);
- free_hot_cold_page(page, 0);
+ free_hot_cold_page(page, false);
}
static void __put_compound_page(struct page *page)
@@ -73,67 +79,187 @@ static void __put_compound_page(struct page *page)
(*dtor)(page);
}
-static void put_compound_page(struct page *page)
+/**
+ * Two special cases here: we could avoid taking compound_lock_irqsave
+ * and could skip the tail refcounting(in _mapcount).
+ *
+ * 1. Hugetlbfs page:
+ *
+ * PageHeadHuge will remain true until the compound page
+ * is released and enters the buddy allocator, and it could
+ * not be split by __split_huge_page_refcount().
+ *
+ * So if we see PageHeadHuge set, and we have the tail page pin,
+ * then we could safely put head page.
+ *
+ * 2. Slab THP page:
+ *
+ * PG_slab is cleared before the slab frees the head page, and
+ * tail pin cannot be the last reference left on the head page,
+ * because the slab code is free to reuse the compound page
+ * after a kfree/kmem_cache_free without having to check if
+ * there's any tail pin left. In turn all tail pinsmust be always
+ * released while the head is still pinned by the slab code
+ * and so we know PG_slab will be still set too.
+ *
+ * So if we see PageSlab set, and we have the tail page pin,
+ * then we could safely put head page.
+ */
+static __always_inline
+void put_unrefcounted_compound_page(struct page *page_head, struct page *page)
{
- if (unlikely(PageTail(page))) {
- /* __split_huge_page_refcount can run under us */
- struct page *page_head = compound_trans_head(page);
-
- if (likely(page != page_head &&
- get_page_unless_zero(page_head))) {
- unsigned long flags;
- /*
- * page_head wasn't a dangling pointer but it
- * may not be a head page anymore by the time
- * we obtain the lock. That is ok as long as it
- * can't be freed from under us.
- */
- flags = compound_lock_irqsave(page_head);
- if (unlikely(!PageTail(page))) {
- /* __split_huge_page_refcount run before us */
- compound_unlock_irqrestore(page_head, flags);
- VM_BUG_ON(PageHead(page_head));
- if (put_page_testzero(page_head))
- __put_single_page(page_head);
- out_put_single:
- if (put_page_testzero(page))
- __put_single_page(page);
- return;
- }
- VM_BUG_ON(page_head != page->first_page);
+ /*
+ * If @page is a THP tail, we must read the tail page
+ * flags after the head page flags. The
+ * __split_huge_page_refcount side enforces write memory barriers
+ * between clearing PageTail and before the head page
+ * can be freed and reallocated.
+ */
+ smp_rmb();
+ if (likely(PageTail(page))) {
+ /*
+ * __split_huge_page_refcount cannot race
+ * here, see the comment above this function.
+ */
+ VM_BUG_ON_PAGE(!PageHead(page_head), page_head);
+ VM_BUG_ON_PAGE(page_mapcount(page) != 0, page);
+ if (put_page_testzero(page_head)) {
/*
- * We can release the refcount taken by
- * get_page_unless_zero() now that
- * __split_huge_page_refcount() is blocked on
- * the compound_lock.
+ * If this is the tail of a slab THP page,
+ * the tail pin must not be the last reference
+ * held on the page, because the PG_slab cannot
+ * be cleared before all tail pins (which skips
+ * the _mapcount tail refcounting) have been
+ * released.
+ *
+ * If this is the tail of a hugetlbfs page,
+ * the tail pin may be the last reference on
+ * the page instead, because PageHeadHuge will
+ * not go away until the compound page enters
+ * the buddy allocator.
*/
- if (put_page_testzero(page_head))
- VM_BUG_ON(1);
- /* __split_huge_page_refcount will wait now */
- VM_BUG_ON(page_mapcount(page) <= 0);
- atomic_dec(&page->_mapcount);
- VM_BUG_ON(atomic_read(&page_head->_count) <= 0);
- VM_BUG_ON(atomic_read(&page->_count) != 0);
+ VM_BUG_ON_PAGE(PageSlab(page_head), page_head);
+ __put_compound_page(page_head);
+ }
+ } else
+ /*
+ * __split_huge_page_refcount run before us,
+ * @page was a THP tail. The split @page_head
+ * has been freed and reallocated as slab or
+ * hugetlbfs page of smaller order (only
+ * possible if reallocated as slab on x86).
+ */
+ if (put_page_testzero(page))
+ __put_single_page(page);
+}
+
+static __always_inline
+void put_refcounted_compound_page(struct page *page_head, struct page *page)
+{
+ if (likely(page != page_head && get_page_unless_zero(page_head))) {
+ unsigned long flags;
+
+ /*
+ * @page_head wasn't a dangling pointer but it may not
+ * be a head page anymore by the time we obtain the
+ * lock. That is ok as long as it can't be freed from
+ * under us.
+ */
+ flags = compound_lock_irqsave(page_head);
+ if (unlikely(!PageTail(page))) {
+ /* __split_huge_page_refcount run before us */
compound_unlock_irqrestore(page_head, flags);
if (put_page_testzero(page_head)) {
+ /*
+ * The @page_head may have been freed
+ * and reallocated as a compound page
+ * of smaller order and then freed
+ * again. All we know is that it
+ * cannot have become: a THP page, a
+ * compound page of higher order, a
+ * tail page. That is because we
+ * still hold the refcount of the
+ * split THP tail and page_head was
+ * the THP head before the split.
+ */
if (PageHead(page_head))
__put_compound_page(page_head);
else
__put_single_page(page_head);
}
- } else {
- /* page_head is a dangling pointer */
- VM_BUG_ON(PageTail(page));
- goto out_put_single;
+out_put_single:
+ if (put_page_testzero(page))
+ __put_single_page(page);
+ return;
}
- } else if (put_page_testzero(page)) {
- if (PageHead(page))
- __put_compound_page(page);
- else
- __put_single_page(page);
+ VM_BUG_ON_PAGE(page_head != page->first_page, page);
+ /*
+ * We can release the refcount taken by
+ * get_page_unless_zero() now that
+ * __split_huge_page_refcount() is blocked on the
+ * compound_lock.
+ */
+ if (put_page_testzero(page_head))
+ VM_BUG_ON_PAGE(1, page_head);
+ /* __split_huge_page_refcount will wait now */
+ VM_BUG_ON_PAGE(page_mapcount(page) <= 0, page);
+ atomic_dec(&page->_mapcount);
+ VM_BUG_ON_PAGE(atomic_read(&page_head->_count) <= 0, page_head);
+ VM_BUG_ON_PAGE(atomic_read(&page->_count) != 0, page);
+ compound_unlock_irqrestore(page_head, flags);
+
+ if (put_page_testzero(page_head)) {
+ if (PageHead(page_head))
+ __put_compound_page(page_head);
+ else
+ __put_single_page(page_head);
+ }
+ } else {
+ /* @page_head is a dangling pointer */
+ VM_BUG_ON_PAGE(PageTail(page), page);
+ goto out_put_single;
}
}
+static void put_compound_page(struct page *page)
+{
+ struct page *page_head;
+
+ /*
+ * We see the PageCompound set and PageTail not set, so @page maybe:
+ * 1. hugetlbfs head page, or
+ * 2. THP head page.
+ */
+ if (likely(!PageTail(page))) {
+ if (put_page_testzero(page)) {
+ /*
+ * By the time all refcounts have been released
+ * split_huge_page cannot run anymore from under us.
+ */
+ if (PageHead(page))
+ __put_compound_page(page);
+ else
+ __put_single_page(page);
+ }
+ return;
+ }
+
+ /*
+ * We see the PageCompound set and PageTail set, so @page maybe:
+ * 1. a tail hugetlbfs page, or
+ * 2. a tail THP page, or
+ * 3. a split THP page.
+ *
+ * Case 3 is possible, as we may race with
+ * __split_huge_page_refcount tearing down a THP page.
+ */
+ page_head = compound_head_by_tail(page);
+ if (!__compound_tail_refcounted(page_head))
+ put_unrefcounted_compound_page(page_head, page);
+ else
+ put_refcounted_compound_page(page_head, page);
+}
+
void put_page(struct page *page)
{
if (unlikely(PageCompound(page)))
@@ -158,9 +284,36 @@ bool __get_page_tail(struct page *page)
* split_huge_page().
*/
unsigned long flags;
- bool got = false;
- struct page *page_head = compound_trans_head(page);
+ bool got;
+ struct page *page_head = compound_head(page);
+ /* Ref to put_compound_page() comment. */
+ if (!__compound_tail_refcounted(page_head)) {
+ smp_rmb();
+ if (likely(PageTail(page))) {
+ /*
+ * This is a hugetlbfs page or a slab
+ * page. __split_huge_page_refcount
+ * cannot race here.
+ */
+ VM_BUG_ON_PAGE(!PageHead(page_head), page_head);
+ __get_page_tail_foll(page, true);
+ return true;
+ } else {
+ /*
+ * __split_huge_page_refcount run
+ * before us, "page" was a THP
+ * tail. The split page_head has been
+ * freed and reallocated as slab or
+ * hugetlbfs page of smaller order
+ * (only possible if reallocated as
+ * slab on x86).
+ */
+ return false;
+ }
+ }
+
+ got = false;
if (likely(page != page_head && get_page_unless_zero(page_head))) {
/*
* page_head wasn't a dangling pointer but it
@@ -201,12 +354,65 @@ void put_pages_list(struct list_head *pages)
}
EXPORT_SYMBOL(put_pages_list);
+/*
+ * get_kernel_pages() - pin kernel pages in memory
+ * @kiov: An array of struct kvec structures
+ * @nr_segs: number of segments to pin
+ * @write: pinning for read/write, currently ignored
+ * @pages: array that receives pointers to the pages pinned.
+ * Should be at least nr_segs long.
+ *
+ * Returns number of pages pinned. This may be fewer than the number
+ * requested. If nr_pages is 0 or negative, returns 0. If no pages
+ * were pinned, returns -errno. Each page returned must be released
+ * with a put_page() call when it is finished with.
+ */
+int get_kernel_pages(const struct kvec *kiov, int nr_segs, int write,
+ struct page **pages)
+{
+ int seg;
+
+ for (seg = 0; seg < nr_segs; seg++) {
+ if (WARN_ON(kiov[seg].iov_len != PAGE_SIZE))
+ return seg;
+
+ pages[seg] = kmap_to_page(kiov[seg].iov_base);
+ page_cache_get(pages[seg]);
+ }
+
+ return seg;
+}
+EXPORT_SYMBOL_GPL(get_kernel_pages);
+
+/*
+ * get_kernel_page() - pin a kernel page in memory
+ * @start: starting kernel address
+ * @write: pinning for read/write, currently ignored
+ * @pages: array that receives pointer to the page pinned.
+ * Must be at least nr_segs long.
+ *
+ * Returns 1 if page is pinned. If the page was not pinned, returns
+ * -errno. The page returned must be released with a put_page() call
+ * when it is finished with.
+ */
+int get_kernel_page(unsigned long start, int write, struct page **pages)
+{
+ const struct kvec kiov = {
+ .iov_base = (void *)start,
+ .iov_len = PAGE_SIZE
+ };
+
+ return get_kernel_pages(&kiov, 1, write, pages);
+}
+EXPORT_SYMBOL_GPL(get_kernel_page);
+
static void pagevec_lru_move_fn(struct pagevec *pvec,
- void (*move_fn)(struct page *page, void *arg),
- void *arg)
+ void (*move_fn)(struct page *page, struct lruvec *lruvec, void *arg),
+ void *arg)
{
int i;
struct zone *zone = NULL;
+ struct lruvec *lruvec;
unsigned long flags = 0;
for (i = 0; i < pagevec_count(pvec); i++) {
@@ -220,7 +426,8 @@ static void pagevec_lru_move_fn(struct pagevec *pvec,
spin_lock_irqsave(&zone->lru_lock, flags);
}
- (*move_fn)(page, arg);
+ lruvec = mem_cgroup_page_lruvec(page, zone);
+ (*move_fn)(page, lruvec, arg);
}
if (zone)
spin_unlock_irqrestore(&zone->lru_lock, flags);
@@ -228,16 +435,13 @@ static void pagevec_lru_move_fn(struct pagevec *pvec,
pagevec_reinit(pvec);
}
-static void pagevec_move_tail_fn(struct page *page, void *arg)
+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);
- struct lruvec *lruvec;
-
- lruvec = mem_cgroup_lru_move_lists(page_zone(page),
- page, lru, lru);
list_move_tail(&page->lru, &lruvec->lists[lru]);
(*pgmoved)++;
}
@@ -269,48 +473,38 @@ void rotate_reclaimable_page(struct page *page)
page_cache_get(page);
local_irq_save(flags);
- pvec = &__get_cpu_var(lru_rotate_pvecs);
+ pvec = this_cpu_ptr(&lru_rotate_pvecs);
if (!pagevec_add(pvec, page))
pagevec_move_tail(pvec);
local_irq_restore(flags);
}
}
-static void update_page_reclaim_stat(struct zone *zone, struct page *page,
+static void update_page_reclaim_stat(struct lruvec *lruvec,
int file, int rotated)
{
- struct zone_reclaim_stat *reclaim_stat = &zone->reclaim_stat;
- struct zone_reclaim_stat *memcg_reclaim_stat;
-
- memcg_reclaim_stat = mem_cgroup_get_reclaim_stat_from_page(page);
+ struct zone_reclaim_stat *reclaim_stat = &lruvec->reclaim_stat;
reclaim_stat->recent_scanned[file]++;
if (rotated)
reclaim_stat->recent_rotated[file]++;
-
- if (!memcg_reclaim_stat)
- return;
-
- memcg_reclaim_stat->recent_scanned[file]++;
- if (rotated)
- memcg_reclaim_stat->recent_rotated[file]++;
}
-static void __activate_page(struct page *page, void *arg)
+static void __activate_page(struct page *page, struct lruvec *lruvec,
+ void *arg)
{
- struct zone *zone = page_zone(page);
-
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);
+ del_page_from_lru_list(page, lruvec, lru);
SetPageActive(page);
lru += LRU_ACTIVE;
- add_page_to_lru_list(zone, page, lru);
- __count_vm_event(PGACTIVATE);
+ add_page_to_lru_list(page, lruvec, lru);
+ trace_mm_lru_activate(page, page_to_pfn(page));
- update_page_reclaim_stat(zone, page, file, 1);
+ __count_vm_event(PGACTIVATE);
+ update_page_reclaim_stat(lruvec, file, 1);
}
}
@@ -325,6 +519,11 @@ static void activate_page_drain(int cpu)
pagevec_lru_move_fn(pvec, __activate_page, NULL);
}
+static bool need_activate_page_drain(int cpu)
+{
+ return pagevec_count(&per_cpu(activate_page_pvecs, cpu)) != 0;
+}
+
void activate_page(struct page *page)
{
if (PageLRU(page) && !PageActive(page) && !PageUnevictable(page)) {
@@ -342,16 +541,48 @@ static inline void activate_page_drain(int cpu)
{
}
+static bool need_activate_page_drain(int cpu)
+{
+ return false;
+}
+
void activate_page(struct page *page)
{
struct zone *zone = page_zone(page);
spin_lock_irq(&zone->lru_lock);
- __activate_page(page, NULL);
+ __activate_page(page, mem_cgroup_page_lruvec(page, zone), NULL);
spin_unlock_irq(&zone->lru_lock);
}
#endif
+static void __lru_cache_activate_page(struct page *page)
+{
+ struct pagevec *pvec = &get_cpu_var(lru_add_pvec);
+ int i;
+
+ /*
+ * Search backwards on the optimistic assumption that the page being
+ * activated has just been added to this pagevec. Note that only
+ * the local pagevec is examined as a !PageLRU page could be in the
+ * process of being released, reclaimed, migrated or on a remote
+ * pagevec that is currently being drained. Furthermore, marking
+ * a remote pagevec's page PageActive potentially hits a race where
+ * a page is marked PageActive just after it is added to the inactive
+ * list causing accounting errors and BUG_ON checks to trigger.
+ */
+ for (i = pagevec_count(pvec) - 1; i >= 0; i--) {
+ struct page *pagevec_page = pvec->pages[i];
+
+ if (pagevec_page == page) {
+ SetPageActive(page);
+ break;
+ }
+ }
+
+ put_cpu_var(lru_add_pvec);
+}
+
/*
* Mark a page as having seen activity.
*
@@ -362,43 +593,82 @@ void activate_page(struct page *page)
void mark_page_accessed(struct page *page)
{
if (!PageActive(page) && !PageUnevictable(page) &&
- PageReferenced(page) && PageLRU(page)) {
- activate_page(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);
}
}
EXPORT_SYMBOL(mark_page_accessed);
-void __lru_cache_add(struct page *page, enum lru_list lru)
+/*
+ * Used to mark_page_accessed(page) that is not visible yet and when it is
+ * still safe to use non-atomic ops
+ */
+void init_page_accessed(struct page *page)
+{
+ if (!PageReferenced(page))
+ __SetPageReferenced(page);
+}
+EXPORT_SYMBOL(init_page_accessed);
+
+static void __lru_cache_add(struct page *page)
{
- struct pagevec *pvec = &get_cpu_var(lru_add_pvecs)[lru];
+ struct pagevec *pvec = &get_cpu_var(lru_add_pvec);
page_cache_get(page);
- if (!pagevec_add(pvec, page))
- __pagevec_lru_add(pvec, lru);
- put_cpu_var(lru_add_pvecs);
+ if (!pagevec_space(pvec))
+ __pagevec_lru_add(pvec);
+ pagevec_add(pvec, page);
+ put_cpu_var(lru_add_pvec);
}
-EXPORT_SYMBOL(__lru_cache_add);
/**
- * lru_cache_add_lru - add a page to a page list
- * @page: the page to be added to the LRU.
- * @lru: the LRU list to which the page is added.
+ * lru_cache_add: add a page to the page lists
+ * @page: the page to add
*/
-void lru_cache_add_lru(struct page *page, enum lru_list lru)
+void lru_cache_add_anon(struct page *page)
{
- if (PageActive(page)) {
- VM_BUG_ON(PageUnevictable(page));
+ if (PageActive(page))
ClearPageActive(page);
- } else if (PageUnevictable(page)) {
- VM_BUG_ON(PageActive(page));
- ClearPageUnevictable(page);
- }
+ __lru_cache_add(page);
+}
- VM_BUG_ON(PageLRU(page) || PageActive(page) || PageUnevictable(page));
- __lru_cache_add(page, lru);
+void lru_cache_add_file(struct page *page)
+{
+ if (PageActive(page))
+ ClearPageActive(page);
+ __lru_cache_add(page);
+}
+EXPORT_SYMBOL(lru_cache_add_file);
+
+/**
+ * lru_cache_add - add a page to a page list
+ * @page: the page to be added to the LRU.
+ *
+ * Queue the page for addition to the LRU via pagevec. The decision on whether
+ * to add the page to the [in]active [file|anon] list is deferred until the
+ * pagevec is drained. This gives a chance for the caller of lru_cache_add()
+ * have the page added to the active list using mark_page_accessed().
+ */
+void lru_cache_add(struct page *page)
+{
+ VM_BUG_ON_PAGE(PageActive(page) && PageUnevictable(page), page);
+ VM_BUG_ON_PAGE(PageLRU(page), page);
+ __lru_cache_add(page);
}
/**
@@ -414,11 +684,14 @@ void lru_cache_add_lru(struct page *page, enum lru_list lru)
void add_page_to_unevictable_list(struct page *page)
{
struct zone *zone = page_zone(page);
+ struct lruvec *lruvec;
spin_lock_irq(&zone->lru_lock);
+ lruvec = mem_cgroup_page_lruvec(page, zone);
+ ClearPageActive(page);
SetPageUnevictable(page);
SetPageLRU(page);
- add_page_to_lru_list(zone, page, LRU_UNEVICTABLE);
+ add_page_to_lru_list(page, lruvec, LRU_UNEVICTABLE);
spin_unlock_irq(&zone->lru_lock);
}
@@ -443,11 +716,11 @@ void add_page_to_unevictable_list(struct page *page)
* 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)
+static void lru_deactivate_fn(struct page *page, struct lruvec *lruvec,
+ void *arg)
{
int lru, file;
bool active;
- struct zone *zone = page_zone(page);
if (!PageLRU(page))
return;
@@ -460,13 +733,13 @@ static void lru_deactivate_fn(struct page *page, void *arg)
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);
+
+ del_page_from_lru_list(page, lruvec, lru + active);
ClearPageActive(page);
ClearPageReferenced(page);
- add_page_to_lru_list(zone, page, lru);
+ add_page_to_lru_list(page, lruvec, lru);
if (PageWriteback(page) || PageDirty(page)) {
/*
@@ -476,19 +749,17 @@ static void lru_deactivate_fn(struct page *page, void *arg)
*/
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);
+ update_page_reclaim_stat(lruvec, file, 0);
}
/*
@@ -496,17 +767,12 @@ static void lru_deactivate_fn(struct page *page, void *arg)
* Either "cpu" is the current CPU, and preemption has already been
* disabled; or "cpu" is being hot-unplugged, and is already dead.
*/
-static void drain_cpu_pagevecs(int cpu)
+void lru_add_drain_cpu(int cpu)
{
- struct pagevec *pvecs = per_cpu(lru_add_pvecs, cpu);
- struct pagevec *pvec;
- int lru;
+ struct pagevec *pvec = &per_cpu(lru_add_pvec, cpu);
- for_each_lru(lru) {
- pvec = &pvecs[lru - LRU_BASE];
- if (pagevec_count(pvec))
- __pagevec_lru_add(pvec, lru);
- }
+ if (pagevec_count(pvec))
+ __pagevec_lru_add(pvec);
pvec = &per_cpu(lru_rotate_pvecs, cpu);
if (pagevec_count(pvec)) {
@@ -553,7 +819,7 @@ void deactivate_page(struct page *page)
void lru_add_drain(void)
{
- drain_cpu_pagevecs(get_cpu());
+ lru_add_drain_cpu(get_cpu());
put_cpu();
}
@@ -562,12 +828,36 @@ static void lru_add_drain_per_cpu(struct work_struct *dummy)
lru_add_drain();
}
-/*
- * Returns 0 for success
- */
-int lru_add_drain_all(void)
+static DEFINE_PER_CPU(struct work_struct, lru_add_drain_work);
+
+void lru_add_drain_all(void)
{
- return schedule_on_each_cpu(lru_add_drain_per_cpu);
+ static DEFINE_MUTEX(lock);
+ static struct cpumask has_work;
+ int cpu;
+
+ mutex_lock(&lock);
+ get_online_cpus();
+ cpumask_clear(&has_work);
+
+ for_each_online_cpu(cpu) {
+ struct work_struct *work = &per_cpu(lru_add_drain_work, cpu);
+
+ if (pagevec_count(&per_cpu(lru_add_pvec, cpu)) ||
+ pagevec_count(&per_cpu(lru_rotate_pvecs, cpu)) ||
+ pagevec_count(&per_cpu(lru_deactivate_pvecs, cpu)) ||
+ need_activate_page_drain(cpu)) {
+ INIT_WORK(work, lru_add_drain_per_cpu);
+ schedule_work_on(cpu, work);
+ cpumask_set_cpu(cpu, &has_work);
+ }
+ }
+
+ for_each_cpu(cpu, &has_work)
+ flush_work(&per_cpu(lru_add_drain_work, cpu));
+
+ put_online_cpus();
+ mutex_unlock(&lock);
}
/*
@@ -583,11 +873,12 @@ int lru_add_drain_all(void)
* 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)
+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);
for (i = 0; i < nr; i++) {
@@ -615,11 +906,16 @@ void release_pages(struct page **pages, int nr, int cold)
zone = pagezone;
spin_lock_irqsave(&zone->lru_lock, flags);
}
- VM_BUG_ON(!PageLRU(page));
+
+ lruvec = mem_cgroup_page_lruvec(page, zone);
+ VM_BUG_ON_PAGE(!PageLRU(page), page);
__ClearPageLRU(page);
- del_page_from_lru_list(zone, page, page_off_lru(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)
@@ -649,38 +945,27 @@ EXPORT_SYMBOL(__pagevec_release);
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
/* used by __split_huge_page_refcount() */
-void lru_add_page_tail(struct zone* zone,
- struct page *page, struct page *page_tail)
+void lru_add_page_tail(struct page *page, struct page *page_tail,
+ struct lruvec *lruvec, struct list_head *list)
{
- int 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(&zone->lru_lock));
+ 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_zone(lruvec)->lru_lock));
- SetPageLRU(page_tail);
-
- if (page_evictable(page_tail, NULL)) {
- if (PageActive(page)) {
- SetPageActive(page_tail);
- active = 1;
- lru = LRU_ACTIVE_ANON;
- } else {
- active = 0;
- lru = LRU_INACTIVE_ANON;
- }
- update_page_reclaim_stat(zone, page_tail, file, active);
- } else {
- SetPageUnevictable(page_tail);
- lru = LRU_UNEVICTABLE;
- }
+ if (!list)
+ SetPageLRU(page_tail);
if (likely(PageLRU(page)))
list_add_tail(&page_tail->lru, &page->lru);
- else {
+ 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,
@@ -689,44 +974,93 @@ void lru_add_page_tail(struct zone* zone,
* 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(zone, page_tail, lru);
+ 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));
}
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
-static void __pagevec_lru_add_fn(struct page *page, void *arg)
+static void __pagevec_lru_add_fn(struct page *page, struct lruvec *lruvec,
+ void *arg)
{
- enum lru_list lru = (enum lru_list)arg;
- struct zone *zone = page_zone(page);
- int file = is_file_lru(lru);
- int active = is_active_lru(lru);
+ int file = page_is_file_cache(page);
+ int active = PageActive(page);
+ enum lru_list lru = page_lru(page);
- VM_BUG_ON(PageActive(page));
- VM_BUG_ON(PageUnevictable(page));
- VM_BUG_ON(PageLRU(page));
+ VM_BUG_ON_PAGE(PageLRU(page), page);
SetPageLRU(page);
- if (active)
- SetPageActive(page);
- update_page_reclaim_stat(zone, page, file, active);
- add_page_to_lru_list(zone, page, lru);
+ add_page_to_lru_list(page, lruvec, lru);
+ update_page_reclaim_stat(lruvec, file, active);
+ trace_mm_lru_insertion(page, page_to_pfn(page), lru, trace_pagemap_flags(page));
}
/*
* Add the passed pages to the LRU, then drop the caller's refcount
* on them. Reinitialises the caller's pagevec.
*/
-void __pagevec_lru_add(struct pagevec *pvec, enum lru_list lru)
+void __pagevec_lru_add(struct pagevec *pvec)
{
- VM_BUG_ON(is_unevictable_lru(lru));
-
- pagevec_lru_move_fn(pvec, __pagevec_lru_add_fn, (void *)lru);
+ pagevec_lru_move_fn(pvec, __pagevec_lru_add_fn, NULL);
}
EXPORT_SYMBOL(__pagevec_lru_add);
/**
+ * pagevec_lookup_entries - gang pagecache lookup
+ * @pvec: Where the resulting entries are placed
+ * @mapping: The address_space to search
+ * @start: The starting entry index
+ * @nr_entries: The maximum number of entries
+ * @indices: The cache indices corresponding to the entries in @pvec
+ *
+ * pagevec_lookup_entries() will search for and return a group of up
+ * to @nr_entries pages and shadow entries in the mapping. All
+ * entries are placed in @pvec. pagevec_lookup_entries() takes a
+ * reference against actual pages in @pvec.
+ *
+ * The search returns a group of mapping-contiguous entries with
+ * ascending indexes. There may be holes in the indices due to
+ * not-present entries.
+ *
+ * pagevec_lookup_entries() returns the number of entries which were
+ * found.
+ */
+unsigned pagevec_lookup_entries(struct pagevec *pvec,
+ struct address_space *mapping,
+ pgoff_t start, unsigned nr_pages,
+ pgoff_t *indices)
+{
+ pvec->nr = find_get_entries(mapping, start, nr_pages,
+ pvec->pages, indices);
+ return pagevec_count(pvec);
+}
+
+/**
+ * pagevec_remove_exceptionals - pagevec exceptionals pruning
+ * @pvec: The pagevec to prune
+ *
+ * pagevec_lookup_entries() fills both pages and exceptional radix
+ * tree entries into the pagevec. This function prunes all
+ * exceptionals from @pvec without leaving holes, so that it can be
+ * passed on to page-only pagevec operations.
+ */
+void pagevec_remove_exceptionals(struct pagevec *pvec)
+{
+ int i, j;
+
+ for (i = 0, j = 0; i < pagevec_count(pvec); i++) {
+ struct page *page = pvec->pages[i];
+ if (!radix_tree_exceptional_entry(page))
+ pvec->pages[j++] = page;
+ }
+ pvec->nr = j;
+}
+
+/**
* pagevec_lookup - gang pagecache lookup
* @pvec: Where the resulting pages are placed
* @mapping: The address_space to search
@@ -765,9 +1099,15 @@ EXPORT_SYMBOL(pagevec_lookup_tag);
void __init swap_setup(void)
{
unsigned long megs = totalram_pages >> (20 - PAGE_SHIFT);
-
#ifdef CONFIG_SWAP
- bdi_init(swapper_space.backing_dev_info);
+ int i;
+
+ if (bdi_init(swapper_spaces[0].backing_dev_info))
+ panic("Failed to init swap bdi");
+ for (i = 0; i < MAX_SWAPFILES; i++) {
+ spin_lock_init(&swapper_spaces[i].tree_lock);
+ INIT_LIST_HEAD(&swapper_spaces[i].i_mmap_nonlinear);
+ }
#endif
/* Use a smaller cluster for small-memory machines */