net/mlx4_en: Fix mixed PFC and Global pause user control requests

[pandora-kernel.git] / mm / vmscan.c

diff --git a/mm/vmscan.c b/mm/vmscan.c
index b9eaa06..4de949b 100644 (file)
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1085,6 +1085,7 @@ int __isolate_lru_page(struct page *page, isolate_mode_t mode, int file)
 
                if (PageDirty(page)) {
                        struct address_space *mapping;
+                       bool migrate_dirty;
 
                        /* ISOLATE_CLEAN means only clean pages */
                        if (mode & ISOLATE_CLEAN)
@@ -1093,10 +1094,19 @@ int __isolate_lru_page(struct page *page, isolate_mode_t mode, int file)
                        /*
                         * Only pages without mappings or that have a
                         * ->migratepage callback are possible to migrate
-                        * without blocking
+                        * without blocking. However, we can be racing with
+                        * truncation so it's necessary to lock the page
+                        * to stabilise the mapping as truncation holds
+                        * the page lock until after the page is removed
+                        * from the page cache.
                         */
+                       if (!trylock_page(page))
+                               return ret;
+
                        mapping = page_mapping(page);
-                       if (mapping && !mapping->a_ops->migratepage)
+                       migrate_dirty = mapping && mapping->a_ops->migratepage;
+                       unlock_page(page);
+                       if (!migrate_dirty)
                                return ret;
                }
        }
@@ -1911,7 +1921,8 @@ static void get_scan_count(struct zone *zone, struct scan_control *sc,
         * latencies, so it's better to scan a minimum amount there as
         * well.
         */
-       if (scanning_global_lru(sc) && current_is_kswapd())
+       if (scanning_global_lru(sc) && current_is_kswapd() &&
+           zone->all_unreclaimable)
                force_scan = true;
        if (!scanning_global_lru(sc))
                force_scan = true;
@@ -1976,10 +1987,10 @@ static void get_scan_count(struct zone *zone, struct scan_control *sc,
         * proportional to the fraction of recently scanned pages on
         * each list that were recently referenced and in active use.
         */
-       ap = (anon_prio + 1) * (reclaim_stat->recent_scanned[0] + 1);
+       ap = anon_prio * (reclaim_stat->recent_scanned[0] + 1);
        ap /= reclaim_stat->recent_rotated[0] + 1;
 
-       fp = (file_prio + 1) * (reclaim_stat->recent_scanned[1] + 1);
+       fp = file_prio * (reclaim_stat->recent_scanned[1] + 1);
        fp /= reclaim_stat->recent_rotated[1] + 1;
        spin_unlock_irq(&zone->lru_lock);
 
@@ -1992,7 +2003,7 @@ out:
                unsigned long scan;
 
                scan = zone_nr_lru_pages(zone, sc, l);
-               if (priority || noswap) {
+               if (priority || noswap || !vmscan_swappiness(sc)) {
                        scan >>= priority;
                        if (!scan && force_scan)
                                scan = SWAP_CLUSTER_MAX;
@@ -2294,7 +2305,6 @@ static unsigned long do_try_to_free_pages(struct zonelist *zonelist,
        unsigned long writeback_threshold;
        bool aborted_reclaim;
 
-       get_mems_allowed();
        delayacct_freepages_start();
 
        if (scanning_global_lru(sc))
@@ -2358,7 +2368,6 @@ static unsigned long do_try_to_free_pages(struct zonelist *zonelist,
 
 out:
        delayacct_freepages_end();
-       put_mems_allowed();
 
        if (sc->nr_reclaimed)
                return sc->nr_reclaimed;
@@ -3016,6 +3025,11 @@ static int kswapd(void *p)
                                                &balanced_classzone_idx);
                }
        }
+
+       tsk->flags &= ~(PF_MEMALLOC | PF_SWAPWRITE | PF_KSWAPD);
+       current->reclaim_state = NULL;
+       lockdep_clear_current_reclaim_state();
+
        return 0;
 }