1 files changed, 37 insertions, 6 deletions

diff --git a/mm/vmscan.c b/mm/vmscan.c
index d16bf5a53266..1ee4b69a28a5 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -674,8 +674,10 @@ static enum page_references page_check_references(struct page *page,
 static unsigned long shrink_page_list(struct list_head *page_list,
                                       struct zone *zone,
                                       struct scan_control *sc,
+                                      enum ttu_flags ttu_flags,
                                       unsigned long *ret_nr_dirty,
-                                      unsigned long *ret_nr_writeback)
+                                      unsigned long *ret_nr_writeback,
+                                      bool force_reclaim)
 {
         LIST_HEAD(ret_pages);
         LIST_HEAD(free_pages);
@@ -689,10 +691,10 @@ static unsigned long shrink_page_list(struct list_head *page_list,
 
         mem_cgroup_uncharge_start();
         while (!list_empty(page_list)) {
-                enum page_references references;
                 struct address_space *mapping;
                 struct page *page;
                 int may_enter_fs;
+                enum page_references references = PAGEREF_RECLAIM_CLEAN;
 
                 cond_resched();
 
@@ -758,7 +760,9 @@ static unsigned long shrink_page_list(struct list_head *page_list,
                         wait_on_page_writeback(page);
                 }
 
-                references = page_check_references(page, sc);
+                if (!force_reclaim)
+                        references = page_check_references(page, sc);
+
                 switch (references) {
                 case PAGEREF_ACTIVATE:
                         goto activate_locked;
@@ -788,7 +792,7 @@ static unsigned long shrink_page_list(struct list_head *page_list,
                  * processes. Try to unmap it here.
                  */
                 if (page_mapped(page) && mapping) {
-                        switch (try_to_unmap(page, TTU_UNMAP)) {
+                        switch (try_to_unmap(page, ttu_flags)) {
                         case SWAP_FAIL:
                                 goto activate_locked;
                         case SWAP_AGAIN:
@@ -960,6 +964,33 @@ keep:
         return nr_reclaimed;
 }
 
+unsigned long reclaim_clean_pages_from_list(struct zone *zone,
+                                            struct list_head *page_list)
+{
+        struct scan_control sc = {
+                .gfp_mask = GFP_KERNEL,
+                .priority = DEF_PRIORITY,
+                .may_unmap = 1,
+        };
+        unsigned long ret, dummy1, dummy2;
+        struct page *page, *next;
+        LIST_HEAD(clean_pages);
+
+        list_for_each_entry_safe(page, next, page_list, lru) {
+                if (page_is_file_cache(page) && !PageDirty(page)) {
+                        ClearPageActive(page);
+                        list_move(&page->lru, &clean_pages);
+                }
+        }
+
+        ret = shrink_page_list(&clean_pages, zone, &sc,
+                                TTU_UNMAP|TTU_IGNORE_ACCESS,
+                                &dummy1, &dummy2, true);
+        list_splice(&clean_pages, page_list);
+        __mod_zone_page_state(zone, NR_ISOLATED_FILE, -ret);
+        return ret;
+}
+
 /*
  * Attempt to remove the specified page from its LRU.  Only take this page
  * if it is of the appropriate PageActive status.  Pages which are being
@@ -1278,8 +1309,8 @@ shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec,
         if (nr_taken == 0)
                 return 0;
 
-        nr_reclaimed = shrink_page_list(&page_list, zone, sc,
-                                                &nr_dirty, &nr_writeback);
+        nr_reclaimed = shrink_page_list(&page_list, zone, sc, TTU_UNMAP,
+                                        &nr_dirty, &nr_writeback, false);
 
         spin_lock_irq(&zone->lru_lock);