1 files changed, 75 insertions, 45 deletions

diff --git a/mm/vmscan.c b/mm/vmscan.c
index 399d54e8a82c..d9fc2dce93af 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -51,6 +51,12 @@
 #define CREATE_TRACE_POINTS
 #include <trace/events/vmscan.h>
 
+enum lumpy_mode {
+        LUMPY_MODE_NONE,
+        LUMPY_MODE_ASYNC,
+        LUMPY_MODE_SYNC,
+};
+
 struct scan_control {
         /* Incremented by the number of inactive pages that were scanned */
         unsigned long nr_scanned;
@@ -82,7 +88,7 @@ struct scan_control {
          * Intend to reclaim enough continuous memory rather than reclaim
          * enough amount of memory. i.e, mode for high order allocation.
          */
-        bool lumpy_reclaim_mode;
+        enum lumpy_mode lumpy_reclaim_mode;
 
         /* Which cgroup do we reclaim from */
         struct mem_cgroup *mem_cgroup;
@@ -265,6 +271,36 @@ unsigned long shrink_slab(unsigned long scanned, gfp_t gfp_mask,
         return ret;
 }
 
+static void set_lumpy_reclaim_mode(int priority, struct scan_control *sc,
+                                   bool sync)
+{
+        enum lumpy_mode mode = sync ? LUMPY_MODE_SYNC : LUMPY_MODE_ASYNC;
+
+        /*
+         * Some reclaim have alredy been failed. No worth to try synchronous
+         * lumpy reclaim.
+         */
+        if (sync && sc->lumpy_reclaim_mode == LUMPY_MODE_NONE)
+                return;
+
+        /*
+         * If we need a large contiguous chunk of memory, or have
+         * trouble getting a small set of contiguous pages, we
+         * will reclaim both active and inactive pages.
+         */
+        if (sc->order > PAGE_ALLOC_COSTLY_ORDER)
+                sc->lumpy_reclaim_mode = mode;
+        else if (sc->order && priority < DEF_PRIORITY - 2)
+                sc->lumpy_reclaim_mode = mode;
+        else
+                sc->lumpy_reclaim_mode = LUMPY_MODE_NONE;
+}
+
+static void disable_lumpy_reclaim_mode(struct scan_control *sc)
+{
+        sc->lumpy_reclaim_mode = LUMPY_MODE_NONE;
+}
+
 static inline int is_page_cache_freeable(struct page *page)
 {
         /*
@@ -275,7 +311,8 @@ static inline int is_page_cache_freeable(struct page *page)
         return page_count(page) - page_has_private(page) == 2;
 }
 
-static int may_write_to_queue(struct backing_dev_info *bdi)
+static int may_write_to_queue(struct backing_dev_info *bdi,
+                              struct scan_control *sc)
 {
         if (current->flags & PF_SWAPWRITE)
                 return 1;
@@ -283,6 +320,10 @@ static int may_write_to_queue(struct backing_dev_info *bdi)
                 return 1;
         if (bdi == current->backing_dev_info)
                 return 1;
+
+        /* lumpy reclaim for hugepage often need a lot of write */
+        if (sc->order > PAGE_ALLOC_COSTLY_ORDER)
+                return 1;
         return 0;
 }
 
@@ -307,12 +348,6 @@ static void handle_write_error(struct address_space *mapping,
         unlock_page(page);
 }
 
-/* Request for sync pageout. */
-enum pageout_io {
-        PAGEOUT_IO_ASYNC,
-        PAGEOUT_IO_SYNC,
-};
-
 /* possible outcome of pageout() */
 typedef enum {
         /* failed to write page out, page is locked */
@@ -330,7 +365,7 @@ typedef enum {
  * Calls ->writepage().
  */
 static pageout_t pageout(struct page *page, struct address_space *mapping,
-                                                enum pageout_io sync_writeback)
+                         struct scan_control *sc)
 {
         /*
          * If the page is dirty, only perform writeback if that write
@@ -366,8 +401,10 @@ static pageout_t pageout(struct page *page, struct address_space *mapping,
         }
         if (mapping->a_ops->writepage == NULL)
                 return PAGE_ACTIVATE;
-        if (!may_write_to_queue(mapping->backing_dev_info))
+        if (!may_write_to_queue(mapping->backing_dev_info, sc)) {
+                disable_lumpy_reclaim_mode(sc);
                 return PAGE_KEEP;
+        }
 
         if (clear_page_dirty_for_io(page)) {
                 int res;
@@ -393,7 +430,8 @@ static pageout_t pageout(struct page *page, struct address_space *mapping,
                  * direct reclaiming a large contiguous area and the
                  * first attempt to free a range of pages fails.
                  */
-                if (PageWriteback(page) && sync_writeback == PAGEOUT_IO_SYNC)
+                if (PageWriteback(page) &&
+                    sc->lumpy_reclaim_mode == LUMPY_MODE_SYNC)
                         wait_on_page_writeback(page);
 
                 if (!PageWriteback(page)) {
@@ -401,7 +439,7 @@ static pageout_t pageout(struct page *page, struct address_space *mapping,
                         ClearPageReclaim(page);
                 }
                 trace_mm_vmscan_writepage(page,
-                        trace_reclaim_flags(page, sync_writeback));
+                        trace_reclaim_flags(page, sc->lumpy_reclaim_mode));
                 inc_zone_page_state(page, NR_VMSCAN_WRITE);
                 return PAGE_SUCCESS;
         }
@@ -579,7 +617,7 @@ static enum page_references page_check_references(struct page *page,
         referenced_page = TestClearPageReferenced(page);
 
         /* Lumpy reclaim - ignore references */
-        if (sc->lumpy_reclaim_mode)
+        if (sc->lumpy_reclaim_mode != LUMPY_MODE_NONE)
                 return PAGEREF_RECLAIM;
 
         /*
@@ -643,8 +681,7 @@ static noinline_for_stack void free_page_list(struct list_head *free_pages)
  * shrink_page_list() returns the number of reclaimed pages
  */
 static unsigned long shrink_page_list(struct list_head *page_list,
-                                        struct scan_control *sc,
-                                        enum pageout_io sync_writeback)
+                                      struct scan_control *sc)
 {
         LIST_HEAD(ret_pages);
         LIST_HEAD(free_pages);
@@ -693,10 +730,13 @@ static unsigned long shrink_page_list(struct list_head *page_list,
                          * for any page for which writeback has already
                          * started.
                          */
-                        if (sync_writeback == PAGEOUT_IO_SYNC && may_enter_fs)
+                        if (sc->lumpy_reclaim_mode == LUMPY_MODE_SYNC &&
+                            may_enter_fs)
                                 wait_on_page_writeback(page);
-                        else
-                                goto keep_locked;
+                        else {
+                                unlock_page(page);
+                                goto keep_lumpy;
+                        }
                 }
 
                 references = page_check_references(page, sc);
@@ -750,14 +790,17 @@ static unsigned long shrink_page_list(struct list_head *page_list,
                                 goto keep_locked;
 
                         /* Page is dirty, try to write it out here */
-                        switch (pageout(page, mapping, sync_writeback)) {
+                        switch (pageout(page, mapping, sc)) {
                         case PAGE_KEEP:
                                 goto keep_locked;
                         case PAGE_ACTIVATE:
                                 goto activate_locked;
                         case PAGE_SUCCESS:
-                                if (PageWriteback(page) || PageDirty(page))
+                                if (PageWriteback(page))
+                                        goto keep_lumpy;
+                                if (PageDirty(page))
                                         goto keep;
+
                                 /*
                                  * A synchronous write - probably a ramdisk.  Go
                                  * ahead and try to reclaim the page.
@@ -840,6 +883,7 @@ cull_mlocked:
                         try_to_free_swap(page);
                 unlock_page(page);
                 putback_lru_page(page);
+                disable_lumpy_reclaim_mode(sc);
                 continue;
 
 activate_locked:
@@ -852,6 +896,8 @@ activate_locked:
 keep_locked:
                 unlock_page(page);
 keep:
+                disable_lumpy_reclaim_mode(sc);
+keep_lumpy:
                 list_add(&page->lru, &ret_pages);
                 VM_BUG_ON(PageLRU(page) || PageUnevictable(page));
         }
@@ -1252,7 +1298,7 @@ static inline bool should_reclaim_stall(unsigned long nr_taken,
                 return false;
 
         /* Only stall on lumpy reclaim */
-        if (!sc->lumpy_reclaim_mode)
+        if (sc->lumpy_reclaim_mode == LUMPY_MODE_NONE)
                 return false;
 
         /* If we have relaimed everything on the isolated list, no stall */
@@ -1297,15 +1343,15 @@ shrink_inactive_list(unsigned long nr_to_scan, struct zone *zone,
                         return SWAP_CLUSTER_MAX;
         }
 
-
+        set_lumpy_reclaim_mode(priority, sc, false);
         lru_add_drain();
         spin_lock_irq(&zone->lru_lock);
 
         if (scanning_global_lru(sc)) {
                 nr_taken = isolate_pages_global(nr_to_scan,
                         &page_list, &nr_scanned, sc->order,
-                        sc->lumpy_reclaim_mode ?
-                                ISOLATE_BOTH : ISOLATE_INACTIVE,
+                        sc->lumpy_reclaim_mode == LUMPY_MODE_NONE ?
+                                        ISOLATE_INACTIVE : ISOLATE_BOTH,
                         zone, 0, file);
                 zone->pages_scanned += nr_scanned;
                 if (current_is_kswapd())
@@ -1317,8 +1363,8 @@ shrink_inactive_list(unsigned long nr_to_scan, struct zone *zone,
         } else {
                 nr_taken = mem_cgroup_isolate_pages(nr_to_scan,
                         &page_list, &nr_scanned, sc->order,
-                        sc->lumpy_reclaim_mode ?
-                                ISOLATE_BOTH : ISOLATE_INACTIVE,
+                        sc->lumpy_reclaim_mode == LUMPY_MODE_NONE ?
+                                        ISOLATE_INACTIVE : ISOLATE_BOTH,
                         zone, sc->mem_cgroup,
                         0, file);
                 /*
@@ -1336,7 +1382,7 @@ shrink_inactive_list(unsigned long nr_to_scan, struct zone *zone,
 
         spin_unlock_irq(&zone->lru_lock);
 
-        nr_reclaimed = shrink_page_list(&page_list, sc, PAGEOUT_IO_ASYNC);
+        nr_reclaimed = shrink_page_list(&page_list, sc);
 
         /* Check if we should syncronously wait for writeback */
         if (should_reclaim_stall(nr_taken, nr_reclaimed, priority, sc)) {
@@ -1347,7 +1393,8 @@ shrink_inactive_list(unsigned long nr_to_scan, struct zone *zone,
                 nr_active = clear_active_flags(&page_list, NULL);
                 count_vm_events(PGDEACTIVATE, nr_active);
 
-                nr_reclaimed += shrink_page_list(&page_list, sc, PAGEOUT_IO_SYNC);
+                set_lumpy_reclaim_mode(priority, sc, true);
+                nr_reclaimed += shrink_page_list(&page_list, sc);
         }
 
         local_irq_disable();
@@ -1739,21 +1786,6 @@ out:
         }
 }
 
-static void set_lumpy_reclaim_mode(int priority, struct scan_control *sc)
-{
-        /*
-         * If we need a large contiguous chunk of memory, or have
-         * trouble getting a small set of contiguous pages, we
-         * will reclaim both active and inactive pages.
-         */
-        if (sc->order > PAGE_ALLOC_COSTLY_ORDER)
-                sc->lumpy_reclaim_mode = 1;
-        else if (sc->order && priority < DEF_PRIORITY - 2)
-                sc->lumpy_reclaim_mode = 1;
-        else
-                sc->lumpy_reclaim_mode = 0;
-}
-
 /*
  * This is a basic per-zone page freer.  Used by both kswapd and direct reclaim.
  */
@@ -1768,8 +1800,6 @@ static void shrink_zone(int priority, struct zone *zone,
 
         get_scan_count(zone, sc, nr, priority);
 
-        set_lumpy_reclaim_mode(priority, sc);
-
         while (nr[LRU_INACTIVE_ANON] || nr[LRU_ACTIVE_FILE] ||
                                         nr[LRU_INACTIVE_FILE]) {
                 for_each_evictable_lru(l) {