Merge branch 'akpm' (Andrew's patch-bomb)

Merge first batch of patches from Andrew Morton:
 "A few misc things and all the MM queue"

* emailed from Andrew Morton <akpm@linux-foundation.org>: (92 commits)
  memcg: avoid THP split in task migration
  thp: add HPAGE_PMD_* definitions for !CONFIG_TRANSPARENT_HUGEPAGE
  memcg: clean up existing move charge code
  mm/memcontrol.c: remove unnecessary 'break' in mem_cgroup_read()
  mm/memcontrol.c: remove redundant BUG_ON() in mem_cgroup_usage_unregister_event()
  mm/memcontrol.c: s/stealed/stolen/
  memcg: fix performance of mem_cgroup_begin_update_page_stat()
  memcg: remove PCG_FILE_MAPPED
  memcg: use new logic for page stat accounting
  memcg: remove PCG_MOVE_LOCK flag from page_cgroup
  memcg: simplify move_account() check
  memcg: remove EXPORT_SYMBOL(mem_cgroup_update_page_stat)
  memcg: kill dead prev_priority stubs
  memcg: remove PCG_CACHE page_cgroup flag
  memcg: let css_get_next() rely upon rcu_read_lock()
  cgroup: revert ss_id_lock to spinlock
  idr: make idr_get_next() good for rcu_read_lock()
  memcg: remove unnecessary thp check in page stat accounting
  memcg: remove redundant returns
  memcg: enum lru_list lru
  ...

1 files changed, 2 insertions, 56 deletions

diff --git a/mm/swapfile.c b/mm/swapfile.c
index 6bf67ab6e46..dae42f380d6 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -932,9 +932,7 @@ static inline int unuse_pmd_range(struct vm_area_struct *vma, pud_t *pud,
 	pmd = pmd_offset(pud, addr);
 	do {
 		next = pmd_addr_end(addr, end);
-		if (unlikely(pmd_trans_huge(*pmd)))
-			continue;
-		if (pmd_none_or_clear_bad(pmd))
+		if (pmd_none_or_trans_huge_or_clear_bad(pmd))
 			continue;
 		ret = unuse_pte_range(vma, pmd, addr, next, entry, page);
 		if (ret)
@@ -2107,7 +2105,7 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
 			p->flags |= SWP_SOLIDSTATE;
 			p->cluster_next = 1 + (random32() % p->highest_bit);
 		}
-		if (discard_swap(p) == 0 && (swap_flags & SWAP_FLAG_DISCARD))
+		if ((swap_flags & SWAP_FLAG_DISCARD) && discard_swap(p) == 0)
 			p->flags |= SWP_DISCARDABLE;
 	}
 
@@ -2292,58 +2290,6 @@ int swapcache_prepare(swp_entry_t entry)
 }
 
 /*
- * swap_lock prevents swap_map being freed. Don't grab an extra
- * reference on the swaphandle, it doesn't matter if it becomes unused.
- */
-int valid_swaphandles(swp_entry_t entry, unsigned long *offset)
-{
-	struct swap_info_struct *si;
-	int our_page_cluster = page_cluster;
-	pgoff_t target, toff;
-	pgoff_t base, end;
-	int nr_pages = 0;
-
-	if (!our_page_cluster)	/* no readahead */
-		return 0;
-
-	si = swap_info[swp_type(entry)];
-	target = swp_offset(entry);
-	base = (target >> our_page_cluster) << our_page_cluster;
-	end = base + (1 << our_page_cluster);
-	if (!base)		/* first page is swap header */
-		base++;
-
-	spin_lock(&swap_lock);
-	if (end > si->max)	/* don't go beyond end of map */
-		end = si->max;
-
-	/* Count contiguous allocated slots above our target */
-	for (toff = target; ++toff < end; nr_pages++) {
-		/* Don't read in free or bad pages */
-		if (!si->swap_map[toff])
-			break;
-		if (swap_count(si->swap_map[toff]) == SWAP_MAP_BAD)
-			break;
-	}
-	/* Count contiguous allocated slots below our target */
-	for (toff = target; --toff >= base; nr_pages++) {
-		/* Don't read in free or bad pages */
-		if (!si->swap_map[toff])
-			break;
-		if (swap_count(si->swap_map[toff]) == SWAP_MAP_BAD)
-			break;
-	}
-	spin_unlock(&swap_lock);
-
-	/*
-	 * Indicate starting offset, and return number of pages to get:
-	 * if only 1, say 0, since there's then no readahead to be done.
-	 */
-	*offset = ++toff;
-	return nr_pages? ++nr_pages: 0;
-}
-
-/*
  * add_swap_count_continuation - called when a swap count is duplicated
  * beyond SWAP_MAP_MAX, it allocates a new page and links that to the entry's
  * page of the original vmalloc'ed swap_map, to hold the continuation count