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-rw-r--r--mm/swap.c106
1 files changed, 68 insertions, 38 deletions
diff --git a/mm/swap.c b/mm/swap.c
index dfd7d71d6841..4a1d0d2c52fa 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -34,10 +34,13 @@
#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);
@@ -384,6 +387,7 @@ static void __activate_page(struct page *page, struct lruvec *lruvec,
SetPageActive(page);
lru += LRU_ACTIVE;
add_page_to_lru_list(page, lruvec, lru);
+ trace_mm_lru_activate(page, page_to_pfn(page));
__count_vm_event(PGACTIVATE);
update_page_reclaim_stat(lruvec, file, 1);
@@ -428,6 +432,33 @@ void activate_page(struct page *page)
}
#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.
*
@@ -438,8 +469,18 @@ 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);
} else if (!PageReferenced(page)) {
SetPageReferenced(page);
@@ -448,42 +489,37 @@ void mark_page_accessed(struct page *page)
EXPORT_SYMBOL(mark_page_accessed);
/*
- * Order of operations is important: flush the pagevec when it's already
- * full, not when adding the last page, to make sure that last page is
- * not added to the LRU directly when passed to this function. Because
- * mark_page_accessed() (called after this when writing) only activates
- * pages that are on the LRU, linear writes in subpage chunks would see
- * every PAGEVEC_SIZE page activated, which is unexpected.
+ * 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, enum lru_list lru)
+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_space(pvec))
- __pagevec_lru_add(pvec, lru);
+ __pagevec_lru_add(pvec);
pagevec_add(pvec, page);
- put_cpu_var(lru_add_pvecs);
+ put_cpu_var(lru_add_pvec);
}
EXPORT_SYMBOL(__lru_cache_add);
/**
- * lru_cache_add_lru - add a page to a page list
+ * lru_cache_add - 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.
*/
-void lru_cache_add_lru(struct page *page, enum lru_list lru)
+void lru_cache_add(struct page *page)
{
if (PageActive(page)) {
VM_BUG_ON(PageUnevictable(page));
- ClearPageActive(page);
} else if (PageUnevictable(page)) {
VM_BUG_ON(PageActive(page));
- ClearPageUnevictable(page);
}
- VM_BUG_ON(PageLRU(page) || PageActive(page) || PageUnevictable(page));
- __lru_cache_add(page, lru);
+ VM_BUG_ON(PageLRU(page));
+ __lru_cache_add(page);
}
/**
@@ -583,15 +619,10 @@ static void lru_deactivate_fn(struct page *page, struct lruvec *lruvec,
*/
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)) {
@@ -708,6 +739,9 @@ void release_pages(struct page **pages, int nr, int cold)
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)
@@ -795,30 +829,26 @@ void lru_add_page_tail(struct page *page, struct page *page_tail,
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);
+ 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));
SetPageLRU(page);
- if (active)
- SetPageActive(page);
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);