Merge branch 'akpm' (patches from Andrew)

Merge second patchbomb from Andrew Morton:

 - the rest of MM

 - various misc bits

 - add ability to run /sbin/reboot at reboot time

 - printk/vsprintf changes

 - fiddle with seq_printf() return value

* akpm: (114 commits)
  parisc: remove use of seq_printf return value
  lru_cache: remove use of seq_printf return value
  tracing: remove use of seq_printf return value
  cgroup: remove use of seq_printf return value
  proc: remove use of seq_printf return value
  s390: remove use of seq_printf return value
  cris fasttimer: remove use of seq_printf return value
  cris: remove use of seq_printf return value
  openrisc: remove use of seq_printf return value
  ARM: plat-pxa: remove use of seq_printf return value
  nios2: cpuinfo: remove use of seq_printf return value
  microblaze: mb: remove use of seq_printf return value
  ipc: remove use of seq_printf return value
  rtc: remove use of seq_printf return value
  power: wakeup: remove use of seq_printf return value
  x86: mtrr: if: remove use of seq_printf return value
  linux/bitmap.h: improve BITMAP_{LAST,FIRST}_WORD_MASK
  MAINTAINERS: CREDITS: remove Stefano Brivio from B43
  .mailmap: add Ricardo Ribalda
  CREDITS: add Ricardo Ribalda Delgado
  ...

1 files changed, 38 insertions, 22 deletions

diff --git a/mm/compaction.c b/mm/compaction.c
index a18201a8124e..018f08da99a2 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -391,28 +391,6 @@ static inline bool compact_should_abort(struct compact_control *cc)
         return false;
 }
 
-/* Returns true if the page is within a block suitable for migration to */
-static bool suitable_migration_target(struct page *page)
-{
-        /* If the page is a large free page, then disallow migration */
-        if (PageBuddy(page)) {
-                /*
-                 * We are checking page_order without zone->lock taken. But
-                 * the only small danger is that we skip a potentially suitable
-                 * pageblock, so it's not worth to check order for valid range.
-                 */
-                if (page_order_unsafe(page) >= pageblock_order)
-                        return false;
-        }
-
-        /* If the block is MIGRATE_MOVABLE or MIGRATE_CMA, allow migration */
-        if (migrate_async_suitable(get_pageblock_migratetype(page)))
-                return true;
-
-        /* Otherwise skip the block */
-        return false;
-}
-
 /*
  * Isolate free pages onto a private freelist. If @strict is true, will abort
  * returning 0 on any invalid PFNs or non-free pages inside of the pageblock
@@ -896,6 +874,29 @@ isolate_migratepages_range(struct compact_control *cc, unsigned long start_pfn,
 
 #endif /* CONFIG_COMPACTION || CONFIG_CMA */
 #ifdef CONFIG_COMPACTION
+
+/* Returns true if the page is within a block suitable for migration to */
+static bool suitable_migration_target(struct page *page)
+{
+        /* If the page is a large free page, then disallow migration */
+        if (PageBuddy(page)) {
+                /*
+                 * We are checking page_order without zone->lock taken. But
+                 * the only small danger is that we skip a potentially suitable
+                 * pageblock, so it's not worth to check order for valid range.
+                 */
+                if (page_order_unsafe(page) >= pageblock_order)
+                        return false;
+        }
+
+        /* If the block is MIGRATE_MOVABLE or MIGRATE_CMA, allow migration */
+        if (migrate_async_suitable(get_pageblock_migratetype(page)))
+                return true;
+
+        /* Otherwise skip the block */
+        return false;
+}
+
 /*
  * Based on information in the current compact_control, find blocks
  * suitable for isolating free pages from and then isolate them.
@@ -1047,6 +1048,12 @@ typedef enum {
 } isolate_migrate_t;
 
 /*
+ * Allow userspace to control policy on scanning the unevictable LRU for
+ * compactable pages.
+ */
+int sysctl_compact_unevictable_allowed __read_mostly = 1;
+
+/*
  * Isolate all pages that can be migrated from the first suitable block,
  * starting at the block pointed to by the migrate scanner pfn within
  * compact_control.
@@ -1057,6 +1064,7 @@ static isolate_migrate_t isolate_migratepages(struct zone *zone,
         unsigned long low_pfn, end_pfn;
         struct page *page;
         const isolate_mode_t isolate_mode =
+                (sysctl_compact_unevictable_allowed ? ISOLATE_UNEVICTABLE : 0) |
                 (cc->mode == MIGRATE_ASYNC ? ISOLATE_ASYNC_MIGRATE : 0);
 
         /*
@@ -1598,6 +1606,14 @@ static void __compact_pgdat(pg_data_t *pgdat, struct compact_control *cc)
                 INIT_LIST_HEAD(&cc->freepages);
                 INIT_LIST_HEAD(&cc->migratepages);
 
+                /*
+                 * When called via /proc/sys/vm/compact_memory
+                 * this makes sure we compact the whole zone regardless of
+                 * cached scanner positions.
+                 */
+                if (cc->order == -1)
+                        __reset_isolation_suitable(zone);
+
                 if (cc->order == -1 || !compaction_deferred(zone, cc->order))
                         compact_zone(zone, cc);