Merge branch 'akpm' (incoming from Andrew Morton)

Merge misc fixes from Andrew Morton:
 "21 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (21 commits)
  mm/balloon_compaction: fix deflation when compaction is disabled
  sh: fix sh770x SCIF memory regions
  zram: avoid NULL pointer access in concurrent situation
  mm/slab_common: don't check for duplicate cache names
  ocfs2: fix d_splice_alias() return code checking
  mm: rmap: split out page_remove_file_rmap()
  mm: memcontrol: fix missed end-writeback page accounting
  mm: page-writeback: inline account_page_dirtied() into single caller
  lib/bitmap.c: fix undefined shift in __bitmap_shift_{left|right}()
  drivers/rtc/rtc-bq32k.c: fix register value
  memory-hotplug: clear pgdat which is allocated by bootmem in try_offline_node()
  drivers/rtc/rtc-s3c.c: fix initialization failure without rtc source clock
  kernel/kmod: fix use-after-free of the sub_info structure
  drivers/rtc/rtc-pm8xxx.c: rework to support pm8941 rtc
  mm, thp: fix collapsing of hugepages on madvise
  drivers: of: add return value to of_reserved_mem_device_init()
  mm: free compound page with correct order
  gcov: add ARM64 to GCOV_PROFILE_ALL
  fsnotify: next_i is freed during fsnotify_unmount_inodes.
  mm/compaction.c: avoid premature range skip in isolate_migratepages_range
  ...

1 files changed, 51 insertions, 37 deletions

diff --git a/mm/rmap.c b/mm/rmap.c
index 116a5053415b..19886fb2f13a 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -1042,15 +1042,46 @@ void page_add_new_anon_rmap(struct page *page,
  */
 void page_add_file_rmap(struct page *page)
 {
-        bool locked;
+        struct mem_cgroup *memcg;
         unsigned long flags;
+        bool locked;
 
-        mem_cgroup_begin_update_page_stat(page, &locked, &flags);
+        memcg = mem_cgroup_begin_page_stat(page, &locked, &flags);
         if (atomic_inc_and_test(&page->_mapcount)) {
                 __inc_zone_page_state(page, NR_FILE_MAPPED);
-                mem_cgroup_inc_page_stat(page, MEM_CGROUP_STAT_FILE_MAPPED);
+                mem_cgroup_inc_page_stat(memcg, MEM_CGROUP_STAT_FILE_MAPPED);
         }
-        mem_cgroup_end_update_page_stat(page, &locked, &flags);
+        mem_cgroup_end_page_stat(memcg, locked, flags);
+}
+
+static void page_remove_file_rmap(struct page *page)
+{
+        struct mem_cgroup *memcg;
+        unsigned long flags;
+        bool locked;
+
+        memcg = mem_cgroup_begin_page_stat(page, &locked, &flags);
+
+        /* page still mapped by someone else? */
+        if (!atomic_add_negative(-1, &page->_mapcount))
+                goto out;
+
+        /* Hugepages are not counted in NR_FILE_MAPPED for now. */
+        if (unlikely(PageHuge(page)))
+                goto out;
+
+        /*
+         * We use the irq-unsafe __{inc|mod}_zone_page_stat because
+         * these counters are not modified in interrupt context, and
+         * pte lock(a spinlock) is held, which implies preemption disabled.
+         */
+        __dec_zone_page_state(page, NR_FILE_MAPPED);
+        mem_cgroup_dec_page_stat(memcg, MEM_CGROUP_STAT_FILE_MAPPED);
+
+        if (unlikely(PageMlocked(page)))
+                clear_page_mlock(page);
+out:
+        mem_cgroup_end_page_stat(memcg, locked, flags);
 }
 
 /**
@@ -1061,46 +1092,33 @@ void page_add_file_rmap(struct page *page)
  */
 void page_remove_rmap(struct page *page)
 {
-        bool anon = PageAnon(page);
-        bool locked;
-        unsigned long flags;
-
-        /*
-         * The anon case has no mem_cgroup page_stat to update; but may
-         * uncharge_page() below, where the lock ordering can deadlock if
-         * we hold the lock against page_stat move: so avoid it on anon.
-         */
-        if (!anon)
-                mem_cgroup_begin_update_page_stat(page, &locked, &flags);
+        if (!PageAnon(page)) {
+                page_remove_file_rmap(page);
+                return;
+        }
 
         /* page still mapped by someone else? */
         if (!atomic_add_negative(-1, &page->_mapcount))
-                goto out;
+                return;
+
+        /* Hugepages are not counted in NR_ANON_PAGES for now. */
+        if (unlikely(PageHuge(page)))
+                return;
 
         /*
-         * Hugepages are not counted in NR_ANON_PAGES nor NR_FILE_MAPPED
-         * and not charged by memcg for now.
-         *
          * We use the irq-unsafe __{inc|mod}_zone_page_stat because
          * these counters are not modified in interrupt context, and
-         * these counters are not modified in interrupt context, and
          * pte lock(a spinlock) is held, which implies preemption disabled.
          */
-        if (unlikely(PageHuge(page)))
-                goto out;
-        if (anon) {
-                if (PageTransHuge(page))
-                        __dec_zone_page_state(page,
-                                              NR_ANON_TRANSPARENT_HUGEPAGES);
-                __mod_zone_page_state(page_zone(page), NR_ANON_PAGES,
-                                -hpage_nr_pages(page));
-        } else {
-                __dec_zone_page_state(page, NR_FILE_MAPPED);
-                mem_cgroup_dec_page_stat(page, MEM_CGROUP_STAT_FILE_MAPPED);
-                mem_cgroup_end_update_page_stat(page, &locked, &flags);
-        }
+        if (PageTransHuge(page))
+                __dec_zone_page_state(page, NR_ANON_TRANSPARENT_HUGEPAGES);
+
+        __mod_zone_page_state(page_zone(page), NR_ANON_PAGES,
+                              -hpage_nr_pages(page));
+
         if (unlikely(PageMlocked(page)))
                 clear_page_mlock(page);
+
         /*
          * It would be tidy to reset the PageAnon mapping here,
          * but that might overwrite a racing page_add_anon_rmap
@@ -1110,10 +1128,6 @@ void page_remove_rmap(struct page *page)
          * Leaving it set also helps swapoff to reinstate ptes
          * faster for those pages still in swapcache.
          */
-        return;
-out:
-        if (!anon)
-                mem_cgroup_end_update_page_stat(page, &locked, &flags);
 }
 
 /*