Merge branch 'akpm' (fixes from Andrew Morton)

Merge patch-bomb from Andrew Morton:
 - part of OCFS2 (review is laggy again)
 - procfs
 - slab
 - all of MM
 - zram, zbud
 - various other random things: arch, filesystems.

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (164 commits)
  nosave: consolidate __nosave_{begin,end} in <asm/sections.h>
  include/linux/screen_info.h: remove unused ORIG_* macros
  kernel/sys.c: compat sysinfo syscall: fix undefined behavior
  kernel/sys.c: whitespace fixes
  acct: eliminate compile warning
  kernel/async.c: switch to pr_foo()
  include/linux/blkdev.h: use NULL instead of zero
  include/linux/kernel.h: deduplicate code implementing clamp* macros
  include/linux/kernel.h: rewrite min3, max3 and clamp using min and max
  alpha: use Kbuild logic to include <asm-generic/sections.h>
  frv: remove deprecated IRQF_DISABLED
  frv: remove unused cpuinfo_frv and friends to fix future build error
  zbud: avoid accessing last unused freelist
  zsmalloc: simplify init_zspage free obj linking
  mm/zsmalloc.c: correct comment for fullness group computation
  zram: use notify_free to account all free notifications
  zram: report maximum used memory
  zram: zram memory size limitation
  zsmalloc: change return value unit of zs_get_total_size_bytes
  zsmalloc: move pages_allocated to zs_pool
  ...

1 files changed, 28 insertions, 84 deletions

diff --git a/mm/vmscan.c b/mm/vmscan.c
index 2836b5373b2e..dcb47074ae03 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -920,7 +920,7 @@ static unsigned long shrink_page_list(struct list_head *page_list,
 			/* Case 1 above */
 			if (current_is_kswapd() &&
 			    PageReclaim(page) &&
-			    zone_is_reclaim_writeback(zone)) {
+			    test_bit(ZONE_WRITEBACK, &zone->flags)) {
 				nr_immediate++;
 				goto keep_locked;
 
@@ -1002,7 +1002,7 @@ static unsigned long shrink_page_list(struct list_head *page_list,
 			 */
 			if (page_is_file_cache(page) &&
 					(!current_is_kswapd() ||
-					 !zone_is_reclaim_dirty(zone))) {
+					 !test_bit(ZONE_DIRTY, &zone->flags))) {
 				/*
 				 * Immediately reclaim when written back.
 				 * Similar in principal to deactivate_page()
@@ -1563,7 +1563,7 @@ shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec,
 	 * are encountered in the nr_immediate check below.
 	 */
 	if (nr_writeback && nr_writeback == nr_taken)
-		zone_set_flag(zone, ZONE_WRITEBACK);
+		set_bit(ZONE_WRITEBACK, &zone->flags);
 
 	/*
 	 * memcg will stall in page writeback so only consider forcibly
@@ -1575,16 +1575,16 @@ shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec,
 		 * backed by a congested BDI and wait_iff_congested will stall.
 		 */
 		if (nr_dirty && nr_dirty == nr_congested)
-			zone_set_flag(zone, ZONE_CONGESTED);
+			set_bit(ZONE_CONGESTED, &zone->flags);
 
 		/*
 		 * If dirty pages are scanned that are not queued for IO, it
 		 * implies that flushers are not keeping up. In this case, flag
-		 * the zone ZONE_TAIL_LRU_DIRTY and kswapd will start writing
-		 * pages from reclaim context.
+		 * the zone ZONE_DIRTY and kswapd will start writing pages from
+		 * reclaim context.
 		 */
 		if (nr_unqueued_dirty == nr_taken)
-			zone_set_flag(zone, ZONE_TAIL_LRU_DIRTY);
+			set_bit(ZONE_DIRTY, &zone->flags);
 
 		/*
 		 * If kswapd scans pages marked marked for immediate
@@ -2315,7 +2315,10 @@ static bool shrink_zone(struct zone *zone, struct scan_control *sc)
 	return reclaimable;
 }
 
-/* Returns true if compaction should go ahead for a high-order request */
+/*
+ * Returns true if compaction should go ahead for a high-order request, or
+ * the high-order allocation would succeed without compaction.
+ */
 static inline bool compaction_ready(struct zone *zone, int order)
 {
 	unsigned long balance_gap, watermark;
@@ -2339,8 +2342,11 @@ static inline bool compaction_ready(struct zone *zone, int order)
 	if (compaction_deferred(zone, order))
 		return watermark_ok;
 
-	/* If compaction is not ready to start, keep reclaiming */
-	if (!compaction_suitable(zone, order))
+	/*
+	 * If compaction is not ready to start and allocation is not likely
+	 * to succeed without it, then keep reclaiming.
+	 */
+	if (compaction_suitable(zone, order) == COMPACT_SKIPPED)
 		return false;
 
 	return watermark_ok;
@@ -2753,21 +2759,22 @@ unsigned long mem_cgroup_shrink_node_zone(struct mem_cgroup *memcg,
 }
 
 unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *memcg,
+					   unsigned long nr_pages,
 					   gfp_t gfp_mask,
-					   bool noswap)
+					   bool may_swap)
 {
 	struct zonelist *zonelist;
 	unsigned long nr_reclaimed;
 	int nid;
 	struct scan_control sc = {
-		.nr_to_reclaim = SWAP_CLUSTER_MAX,
+		.nr_to_reclaim = max(nr_pages, SWAP_CLUSTER_MAX),
 		.gfp_mask = (gfp_mask & GFP_RECLAIM_MASK) |
 				(GFP_HIGHUSER_MOVABLE & ~GFP_RECLAIM_MASK),
 		.target_mem_cgroup = memcg,
 		.priority = DEF_PRIORITY,
 		.may_writepage = !laptop_mode,
 		.may_unmap = 1,
-		.may_swap = !noswap,
+		.may_swap = may_swap,
 	};
 
 	/*
@@ -2818,7 +2825,7 @@ static bool zone_balanced(struct zone *zone, int order,
 		return false;
 
 	if (IS_ENABLED(CONFIG_COMPACTION) && order &&
-	    !compaction_suitable(zone, order))
+	    compaction_suitable(zone, order) == COMPACT_SKIPPED)
 		return false;
 
 	return true;
@@ -2978,7 +2985,7 @@ static bool kswapd_shrink_zone(struct zone *zone,
 	/* Account for the number of pages attempted to reclaim */
 	*nr_attempted += sc->nr_to_reclaim;
 
-	zone_clear_flag(zone, ZONE_WRITEBACK);
+	clear_bit(ZONE_WRITEBACK, &zone->flags);
 
 	/*
 	 * If a zone reaches its high watermark, consider it to be no longer
@@ -2988,8 +2995,8 @@ static bool kswapd_shrink_zone(struct zone *zone,
 	 */
 	if (zone_reclaimable(zone) &&
 	    zone_balanced(zone, testorder, 0, classzone_idx)) {
-		zone_clear_flag(zone, ZONE_CONGESTED);
-		zone_clear_flag(zone, ZONE_TAIL_LRU_DIRTY);
+		clear_bit(ZONE_CONGESTED, &zone->flags);
+		clear_bit(ZONE_DIRTY, &zone->flags);
 	}
 
 	return sc->nr_scanned >= sc->nr_to_reclaim;
@@ -3080,8 +3087,8 @@ static unsigned long balance_pgdat(pg_data_t *pgdat, int order,
 				 * If balanced, clear the dirty and congested
 				 * flags
 				 */
-				zone_clear_flag(zone, ZONE_CONGESTED);
-				zone_clear_flag(zone, ZONE_TAIL_LRU_DIRTY);
+				clear_bit(ZONE_CONGESTED, &zone->flags);
+				clear_bit(ZONE_DIRTY, &zone->flags);
 			}
 		}
 
@@ -3708,11 +3715,11 @@ int zone_reclaim(struct zone *zone, gfp_t gfp_mask, unsigned int order)
 	if (node_state(node_id, N_CPU) && node_id != numa_node_id())
 		return ZONE_RECLAIM_NOSCAN;
 
-	if (zone_test_and_set_flag(zone, ZONE_RECLAIM_LOCKED))
+	if (test_and_set_bit(ZONE_RECLAIM_LOCKED, &zone->flags))
 		return ZONE_RECLAIM_NOSCAN;
 
 	ret = __zone_reclaim(zone, gfp_mask, order);
-	zone_clear_flag(zone, ZONE_RECLAIM_LOCKED);
+	clear_bit(ZONE_RECLAIM_LOCKED, &zone->flags);
 
 	if (!ret)
 		count_vm_event(PGSCAN_ZONE_RECLAIM_FAILED);
@@ -3791,66 +3798,3 @@ void check_move_unevictable_pages(struct page **pages, int nr_pages)
 	}
 }
 #endif /* CONFIG_SHMEM */
-
-static void warn_scan_unevictable_pages(void)
-{
-	printk_once(KERN_WARNING
-		    "%s: The scan_unevictable_pages sysctl/node-interface has been "
-		    "disabled for lack of a legitimate use case.  If you have "
-		    "one, please send an email to linux-mm@kvack.org.\n",
-		    current->comm);
-}
-
-/*
- * scan_unevictable_pages [vm] sysctl handler.  On demand re-scan of
- * all nodes' unevictable lists for evictable pages
- */
-unsigned long scan_unevictable_pages;
-
-int scan_unevictable_handler(struct ctl_table *table, int write,
-			   void __user *buffer,
-			   size_t *length, loff_t *ppos)
-{
-	warn_scan_unevictable_pages();
-	proc_doulongvec_minmax(table, write, buffer, length, ppos);
-	scan_unevictable_pages = 0;
-	return 0;
-}
-
-#ifdef CONFIG_NUMA
-/*
- * per node 'scan_unevictable_pages' attribute.  On demand re-scan of
- * a specified node's per zone unevictable lists for evictable pages.
- */
-
-static ssize_t read_scan_unevictable_node(struct device *dev,
-					  struct device_attribute *attr,
-					  char *buf)
-{
-	warn_scan_unevictable_pages();
-	return sprintf(buf, "0\n");	/* always zero; should fit... */
-}
-
-static ssize_t write_scan_unevictable_node(struct device *dev,
-					   struct device_attribute *attr,
-					const char *buf, size_t count)
-{
-	warn_scan_unevictable_pages();
-	return 1;
-}
-
-
-static DEVICE_ATTR(scan_unevictable_pages, S_IRUGO | S_IWUSR,
-			read_scan_unevictable_node,
-			write_scan_unevictable_node);
-
-int scan_unevictable_register_node(struct node *node)
-{
-	return device_create_file(&node->dev, &dev_attr_scan_unevictable_pages);
-}
-
-void scan_unevictable_unregister_node(struct node *node)
-{
-	device_remove_file(&node->dev, &dev_attr_scan_unevictable_pages);
-}
-#endif