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

Merge misc VM changes from Andrew Morton:
 "The rest of most-of-MM.  The other MM bits await a slab merge.

  This patch includes the addition of a huge zero_page.  Not a
  performance boost but it an save large amounts of physical memory in
  some situations.

  Also a bunch of Fujitsu engineers are working on memory hotplug.
  Which, as it turns out, was badly broken.  About half of their patches
  are included here; the remainder are 3.8 material."

However, this merge disables CONFIG_MOVABLE_NODE, which was totally
broken.  We don't add new features with "default y", nor do we add
Kconfig questions that are incomprehensible to most people without any
help text.  Does the feature even make sense without compaction or
memory hotplug?

* akpm: (54 commits)
  mm/bootmem.c: remove unused wrapper function reserve_bootmem_generic()
  mm/memory.c: remove unused code from do_wp_page()
  asm-generic, mm: pgtable: consolidate zero page helpers
  mm/hugetlb.c: fix warning on freeing hwpoisoned hugepage
  hwpoison, hugetlbfs: fix RSS-counter warning
  hwpoison, hugetlbfs: fix "bad pmd" warning in unmapping hwpoisoned hugepage
  mm: protect against concurrent vma expansion
  memcg: do not check for mm in __mem_cgroup_count_vm_event
  tmpfs: support SEEK_DATA and SEEK_HOLE (reprise)
  mm: provide more accurate estimation of pages occupied by memmap
  fs/buffer.c: remove redundant initialization in alloc_page_buffers()
  fs/buffer.c: do not inline exported function
  writeback: fix a typo in comment
  mm: introduce new field "managed_pages" to struct zone
  mm, oom: remove statically defined arch functions of same name
  mm, oom: remove redundant sleep in pagefault oom handler
  mm, oom: cleanup pagefault oom handler
  memory_hotplug: allow online/offline memory to result movable node
  numa: add CONFIG_MOVABLE_NODE for movable-dedicated node
  mm, memcg: avoid unnecessary function call when memcg is disabled
  ...

Documentation/cgroups/cpusets.txt

@@ -218,7 +218,7 @@ and name space for cpusets, with a minimum of additional kernel code.
 The cpus and mems files in the root (top_cpuset) cpuset are
 read-only.  The cpus file automatically tracks the value of
 cpu_online_mask using a CPU hotplug notifier, and the mems file
-automatically tracks the value of node_states[N_HIGH_MEMORY]--i.e.,
+automatically tracks the value of node_states[N_MEMORY]--i.e.,
 nodes with memory--using the cpuset_track_online_nodes() hook.
 
 

Documentation/memory-hotplug.txt

@@ -390,6 +390,7 @@ struct memory_notify {
        unsigned long start_pfn;
        unsigned long nr_pages;
        int status_change_nid_normal;
+       int status_change_nid_high;
        int status_change_nid;
 }
 
@@ -397,7 +398,9 @@ start_pfn is start_pfn of online/offline memory.
 nr_pages is # of pages of online/offline memory.
 status_change_nid_normal is set node id when N_NORMAL_MEMORY of nodemask
 is (will be) set/clear, if this is -1, then nodemask status is not changed.
-status_change_nid is set node id when N_HIGH_MEMORY of nodemask is (will be)
+status_change_nid_high is set node id when N_HIGH_MEMORY of nodemask
+is (will be) set/clear, if this is -1, then nodemask status is not changed.
+status_change_nid is set node id when N_MEMORY of nodemask is (will be)
 set/clear. It means a new(memoryless) node gets new memory by online and a
 node loses all memory. If this is -1, then nodemask status is not changed.
 If status_changed_nid* >= 0, callback should create/discard structures for the

Documentation/vm/transhuge.txt

@@ -116,6 +116,13 @@ echo always >/sys/kernel/mm/transparent_hugepage/defrag
 echo madvise >/sys/kernel/mm/transparent_hugepage/defrag
 echo never >/sys/kernel/mm/transparent_hugepage/defrag
 
+By default kernel tries to use huge zero page on read page fault.
+It's possible to disable huge zero page by writing 0 or enable it
+back by writing 1:
+
+echo 0 >/sys/kernel/mm/transparent_hugepage/khugepaged/use_zero_page
+echo 1 >/sys/kernel/mm/transparent_hugepage/khugepaged/use_zero_page
+
 khugepaged will be automatically started when
 transparent_hugepage/enabled is set to "always" or "madvise, and it'll
 be automatically shutdown if it's set to "never".
@@ -197,6 +204,14 @@ thp_split is incremented every time a huge page is split into base
 	pages. This can happen for a variety of reasons but a common
 	reason is that a huge page is old and is being reclaimed.
 
+thp_zero_page_alloc is incremented every time a huge zero page is
+	successfully allocated. It includes allocations which where
+	dropped due race with other allocation. Note, it doesn't count
+	every map of the huge zero page, only its allocation.
+
+thp_zero_page_alloc_failed is incremented if kernel fails to allocate
+	huge zero page and falls back to using small pages.
+
 As the system ages, allocating huge pages may be expensive as the
 system uses memory compaction to copy data around memory to free a
 huge page for use. There are some counters in /proc/vmstat to help
@@ -276,7 +291,7 @@ unaffected. libhugetlbfs will also work fine as usual.
 == Graceful fallback ==
 
 Code walking pagetables but unware about huge pmds can simply call
-split_huge_page_pmd(mm, pmd) where the pmd is the one returned by
+split_huge_page_pmd(vma, addr, pmd) where the pmd is the one returned by
 pmd_offset. It's trivial to make the code transparent hugepage aware
 by just grepping for "pmd_offset" and adding split_huge_page_pmd where
 missing after pmd_offset returns the pmd. Thanks to the graceful
@@ -299,7 +314,7 @@ diff --git a/mm/mremap.c b/mm/mremap.c
 		return NULL;
 
 	pmd = pmd_offset(pud, addr);
-+	split_huge_page_pmd(mm, pmd);
++	split_huge_page_pmd(vma, addr, pmd);
 	if (pmd_none_or_clear_bad(pmd))
 		return NULL;
 

arch/mips/include/asm/pgtable.h

@@ -76,16 +76,7 @@ extern unsigned long zero_page_mask;
 
 #define ZERO_PAGE(vaddr) \
 	(virt_to_page((void *)(empty_zero_page + (((unsigned long)(vaddr)) & zero_page_mask))))
-
-#define is_zero_pfn is_zero_pfn
-static inline int is_zero_pfn(unsigned long pfn)
-{
-	extern unsigned long zero_pfn;
-	unsigned long offset_from_zero_pfn = pfn - zero_pfn;
-	return offset_from_zero_pfn <= (zero_page_mask >> PAGE_SHIFT);
-}
-
-#define my_zero_pfn(addr)	page_to_pfn(ZERO_PAGE(addr))
+#define __HAVE_COLOR_ZERO_PAGE
 
 extern void paging_init(void);
 

arch/powerpc/mm/fault.c

@@ -113,19 +113,6 @@ static int store_updates_sp(struct pt_regs *regs)
 #define MM_FAULT_CONTINUE	-1
 #define MM_FAULT_ERR(sig)	(sig)
 
-static int out_of_memory(struct pt_regs *regs)
-{
-	/*
-	 * We ran out of memory, or some other thing happened to us that made
-	 * us unable to handle the page fault gracefully.
-	 */
-	up_read(&current->mm->mmap_sem);
-	if (!user_mode(regs))
-		return MM_FAULT_ERR(SIGKILL);
-	pagefault_out_of_memory();
-	return MM_FAULT_RETURN;
-}
-
 static int do_sigbus(struct pt_regs *regs, unsigned long address)
 {
 	siginfo_t info;
@@ -169,8 +156,18 @@ static int mm_fault_error(struct pt_regs *regs, unsigned long addr, int fault)
 		return MM_FAULT_CONTINUE;
 
 	/* Out of memory */
-	if (fault & VM_FAULT_OOM)
-		return out_of_memory(regs);
+	if (fault & VM_FAULT_OOM) {
+		up_read(&current->mm->mmap_sem);
+
+		/*
+		 * We ran out of memory, or some other thing happened to us that
+		 * made us unable to handle the page fault gracefully.
+		 */
+		if (!user_mode(regs))
+			return MM_FAULT_ERR(SIGKILL);
+		pagefault_out_of_memory();
+		return MM_FAULT_RETURN;
+	}
 
 	/* Bus error. x86 handles HWPOISON here, we'll add this if/when
 	 * we support the feature in HW

arch/s390/include/asm/pgtable.h

@@ -55,16 +55,7 @@ extern unsigned long zero_page_mask;
 #define ZERO_PAGE(vaddr) \
 	(virt_to_page((void *)(empty_zero_page + \
 	 (((unsigned long)(vaddr)) &zero_page_mask))))
-
-#define is_zero_pfn is_zero_pfn
-static inline int is_zero_pfn(unsigned long pfn)
-{
-	extern unsigned long zero_pfn;
-	unsigned long offset_from_zero_pfn = pfn - zero_pfn;
-	return offset_from_zero_pfn <= (zero_page_mask >> PAGE_SHIFT);
-}
-
-#define my_zero_pfn(addr)	page_to_pfn(ZERO_PAGE(addr))
+#define __HAVE_COLOR_ZERO_PAGE
 
 #endif /* !__ASSEMBLY__ */
 

arch/sh/mm/fault.c

@@ -301,17 +301,6 @@ bad_area_access_error(struct pt_regs *regs, unsigned long error_code,
 	__bad_area(regs, error_code, address, SEGV_ACCERR);
 }
 
-static void out_of_memory(void)
-{
-	/*
-	 * We ran out of memory, call the OOM killer, and return the userspace
-	 * (which will retry the fault, or kill us if we got oom-killed):
-	 */
-	up_read(&current->mm->mmap_sem);
-
-	pagefault_out_of_memory();
-}
-
 static void
 do_sigbus(struct pt_regs *regs, unsigned long error_code, unsigned long address)
 {
@@ -353,8 +342,14 @@ mm_fault_error(struct pt_regs *regs, unsigned long error_code,
 			no_context(regs, error_code, address);
 			return 1;
 		}
+		up_read(&current->mm->mmap_sem);
 
-		out_of_memory();
+		/*
+		 * We ran out of memory, call the OOM killer, and return the
+		 * userspace (which will retry the fault, or kill us if we got
+		 * oom-killed):
+		 */
+		pagefault_out_of_memory();
 	} else {
 		if (fault & VM_FAULT_SIGBUS)
 			do_sigbus(regs, error_code, address);

arch/x86/kernel/vm86_32.c

@@ -182,7 +182,7 @@ static void mark_screen_rdonly(struct mm_struct *mm)
 	if (pud_none_or_clear_bad(pud))
 		goto out;
 	pmd = pmd_offset(pud, 0xA0000);
-	split_huge_page_pmd(mm, pmd);
+	split_huge_page_pmd_mm(mm, 0xA0000, pmd);
 	if (pmd_none_or_clear_bad(pmd))
 		goto out;
 	pte = pte_offset_map_lock(mm, pmd, 0xA0000, &ptl);

arch/x86/mm/fault.c

@@ -803,20 +803,6 @@ bad_area_access_error(struct pt_regs *regs, unsigned long error_code,
 	__bad_area(regs, error_code, address, SEGV_ACCERR);
 }
 
-/* TODO: fixup for "mm-invoke-oom-killer-from-page-fault.patch" */
-static void
-out_of_memory(struct pt_regs *regs, unsigned long error_code,
-	      unsigned long address)
-{
-	/*
-	 * We ran out of memory, call the OOM killer, and return the userspace
-	 * (which will retry the fault, or kill us if we got oom-killed):
-	 */
-	up_read(&current->mm->mmap_sem);
-
-	pagefault_out_of_memory();
-}
-
 static void
 do_sigbus(struct pt_regs *regs, unsigned long error_code, unsigned long address,
 	  unsigned int fault)
@@ -879,7 +865,14 @@ mm_fault_error(struct pt_regs *regs, unsigned long error_code,
 			return 1;
 		}
 
-		out_of_memory(regs, error_code, address);
+		up_read(&current->mm->mmap_sem);
+
+		/*
+		 * We ran out of memory, call the OOM killer, and return the
+		 * userspace (which will retry the fault, or kill us if we got
+		 * oom-killed):
+		 */
+		pagefault_out_of_memory();
 	} else {
 		if (fault & (VM_FAULT_SIGBUS|VM_FAULT_HWPOISON|
 			     VM_FAULT_HWPOISON_LARGE))

arch/x86/mm/init_64.c

@@ -630,7 +630,9 @@ void __init paging_init(void)
 	 *	 numa support is not compiled in, and later node_set_state
 	 *	 will not set it back.
 	 */
-	node_clear_state(0, N_NORMAL_MEMORY);
+	node_clear_state(0, N_MEMORY);
+	if (N_MEMORY != N_NORMAL_MEMORY)
+		node_clear_state(0, N_NORMAL_MEMORY);
 
 	zone_sizes_init();
 }

drivers/base/node.c

@@ -227,7 +227,7 @@ static node_registration_func_t __hugetlb_unregister_node;
 static inline bool hugetlb_register_node(struct node *node)
 {
 	if (__hugetlb_register_node &&
-			node_state(node->dev.id, N_HIGH_MEMORY)) {
+			node_state(node->dev.id, N_MEMORY)) {
 		__hugetlb_register_node(node);
 		return true;
 	}
@@ -643,6 +643,9 @@ static struct node_attr node_state_attr[] = {
 	[N_NORMAL_MEMORY] = _NODE_ATTR(has_normal_memory, N_NORMAL_MEMORY),
 #ifdef CONFIG_HIGHMEM
 	[N_HIGH_MEMORY] = _NODE_ATTR(has_high_memory, N_HIGH_MEMORY),
+#endif
+#ifdef CONFIG_MOVABLE_NODE
+	[N_MEMORY] = _NODE_ATTR(has_memory, N_MEMORY),
 #endif
 	[N_CPU] = _NODE_ATTR(has_cpu, N_CPU),
 };
@@ -653,6 +656,9 @@ static struct attribute *node_state_attrs[] = {
 	&node_state_attr[N_NORMAL_MEMORY].attr.attr,
 #ifdef CONFIG_HIGHMEM
 	&node_state_attr[N_HIGH_MEMORY].attr.attr,
+#endif
+#ifdef CONFIG_MOVABLE_NODE
+	&node_state_attr[N_MEMORY].attr.attr,
 #endif
 	&node_state_attr[N_CPU].attr.attr,
 	NULL

fs/buffer.c

@@ -46,8 +46,7 @@ static int fsync_buffers_list(spinlock_t *lock, struct list_head *list);
 
 #define BH_ENTRY(list) list_entry((list), struct buffer_head, b_assoc_buffers)
 
-inline void
-init_buffer(struct buffer_head *bh, bh_end_io_t *handler, void *private)
+void init_buffer(struct buffer_head *bh, bh_end_io_t *handler, void *private)
 {
 	bh->b_end_io = handler;
 	bh->b_private = private;
@@ -850,13 +849,10 @@ try_again:
 		if (!bh)
 			goto no_grow;
 
-		bh->b_bdev = NULL;
 		bh->b_this_page = head;
 		bh->b_blocknr = -1;
 		head = bh;
 
-		bh->b_state = 0;
-		atomic_set(&bh->b_count, 0);
 		bh->b_size = size;
 
 		/* Link the buffer to its page */

fs/fs-writeback.c

@@ -1034,7 +1034,7 @@ int bdi_writeback_thread(void *data)
 	while (!kthread_freezable_should_stop(NULL)) {
 		/*
 		 * Remove own delayed wake-up timer, since we are already awake
-		 * and we'll take care of the preriodic write-back.
+		 * and we'll take care of the periodic write-back.
 		 */
 		del_timer(&wb->wakeup_timer);
 

fs/proc/kcore.c

@@ -249,7 +249,7 @@ static int kcore_update_ram(void)
 	/* Not inialized....update now */
 	/* find out "max pfn" */
 	end_pfn = 0;
-	for_each_node_state(nid, N_HIGH_MEMORY) {
+	for_each_node_state(nid, N_MEMORY) {
 		unsigned long node_end;
 		node_end  = NODE_DATA(nid)->node_start_pfn +
 			NODE_DATA(nid)->node_spanned_pages;

fs/proc/task_mmu.c

@@ -643,7 +643,7 @@ static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr,
 	spinlock_t *ptl;
 	struct page *page;
 
-	split_huge_page_pmd(walk->mm, pmd);
+	split_huge_page_pmd(vma, addr, pmd);
 	if (pmd_trans_unstable(pmd))
 		return 0;
 
@@ -1126,7 +1126,7 @@ static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma,
 		return NULL;
 
 	nid = page_to_nid(page);
-	if (!node_isset(nid, node_states[N_HIGH_MEMORY]))
+	if (!node_isset(nid, node_states[N_MEMORY]))
 		return NULL;
 
 	return page;
@@ -1279,7 +1279,7 @@ static int show_numa_map(struct seq_file *m, void *v, int is_pid)
 	if (md->writeback)
 		seq_printf(m, " writeback=%lu", md->writeback);
 
-	for_each_node_state(n, N_HIGH_MEMORY)
+	for_each_node_state(n, N_MEMORY)
 		if (md->node[n])
 			seq_printf(m, " N%d=%lu", n, md->node[n]);
 out:

include/asm-generic/pgtable.h

@@ -449,6 +449,32 @@ extern void untrack_pfn(struct vm_area_struct *vma, unsigned long pfn,
 			unsigned long size);
 #endif
 
+#ifdef __HAVE_COLOR_ZERO_PAGE
+static inline int is_zero_pfn(unsigned long pfn)
+{
+	extern unsigned long zero_pfn;
+	unsigned long offset_from_zero_pfn = pfn - zero_pfn;
+	return offset_from_zero_pfn <= (zero_page_mask >> PAGE_SHIFT);
+}
+
+static inline unsigned long my_zero_pfn(unsigned long addr)
+{
+	return page_to_pfn(ZERO_PAGE(addr));
+}
+#else
+static inline int is_zero_pfn(unsigned long pfn)
+{
+	extern unsigned long zero_pfn;
+	return pfn == zero_pfn;
+}
+
+static inline unsigned long my_zero_pfn(unsigned long addr)
+{
+	extern unsigned long zero_pfn;
+	return zero_pfn;
+}
+#endif
+
 #ifdef CONFIG_MMU
 
 #ifndef CONFIG_TRANSPARENT_HUGEPAGE

include/linux/bootmem.h

@@ -137,9 +137,6 @@ extern void *__alloc_bootmem_low_node(pg_data_t *pgdat,
 #define alloc_bootmem_low_pages_node(pgdat, x) \
 	__alloc_bootmem_low_node(pgdat, x, PAGE_SIZE, 0)
 
-extern int reserve_bootmem_generic(unsigned long addr, unsigned long size,
-				   int flags);
-
 #ifdef CONFIG_HAVE_ARCH_ALLOC_REMAP
 extern void *alloc_remap(int nid, unsigned long size);
 #else

include/linux/cpuset.h

@@ -144,7 +144,7 @@ static inline nodemask_t cpuset_mems_allowed(struct task_struct *p)
 	return node_possible_map;
 }
 
-#define cpuset_current_mems_allowed (node_states[N_HIGH_MEMORY])
+#define cpuset_current_mems_allowed (node_states[N_MEMORY])
 static inline void cpuset_init_current_mems_allowed(void) {}
 
 static inline int cpuset_nodemask_valid_mems_allowed(nodemask_t *nodemask)

include/linux/gfp.h

@@ -34,6 +34,7 @@ struct vm_area_struct;
 #define ___GFP_NO_KSWAPD	0x400000u
 #define ___GFP_OTHER_NODE	0x800000u
 #define ___GFP_WRITE		0x1000000u
+/* If the above are modified, __GFP_BITS_SHIFT may need updating */
 
 /*
  * GFP bitmasks..

include/linux/huge_mm.h

@@ -39,6 +39,7 @@ enum transparent_hugepage_flag {
 	TRANSPARENT_HUGEPAGE_DEFRAG_FLAG,
 	TRANSPARENT_HUGEPAGE_DEFRAG_REQ_MADV_FLAG,
 	TRANSPARENT_HUGEPAGE_DEFRAG_KHUGEPAGED_FLAG,
+	TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG,
 #ifdef CONFIG_DEBUG_VM
 	TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG,
 #endif
@@ -78,6 +79,9 @@ extern bool is_vma_temporary_stack(struct vm_area_struct *vma);
 	 (transparent_hugepage_flags &					\
 	  (1<<TRANSPARENT_HUGEPAGE_DEFRAG_REQ_MADV_FLAG) &&		\
 	  (__vma)->vm_flags & VM_HUGEPAGE))
+#define transparent_hugepage_use_zero_page()				\
+	(transparent_hugepage_flags &					\
+	 (1<<TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG))
 #ifdef CONFIG_DEBUG_VM
 #define transparent_hugepage_debug_cow()				\
 	(transparent_hugepage_flags &					\
@@ -95,12 +99,14 @@ extern int handle_pte_fault(struct mm_struct *mm,
 			    struct vm_area_struct *vma, unsigned long address,
 			    pte_t *pte, pmd_t *pmd, unsigned int flags);
 extern int split_huge_page(struct page *page);
-extern void __split_huge_page_pmd(struct mm_struct *mm, pmd_t *pmd);
-#define split_huge_page_pmd(__mm, __pmd)				\
+extern void __split_huge_page_pmd(struct vm_area_struct *vma,
+		unsigned long address, pmd_t *pmd);
+#define split_huge_page_pmd(__vma, __address, __pmd)			\
 	do {								\
 		pmd_t *____pmd = (__pmd);				\
 		if (unlikely(pmd_trans_huge(*____pmd)))			\
-			__split_huge_page_pmd(__mm, ____pmd);		\
+			__split_huge_page_pmd(__vma, __address,		\
+					____pmd);			\
 	}  while (0)
 #define wait_split_huge_page(__anon_vma, __pmd)				\
 	do {								\
@@ -110,6 +116,8 @@ extern void __split_huge_page_pmd(struct mm_struct *mm, pmd_t *pmd);
 		BUG_ON(pmd_trans_splitting(*____pmd) ||			\
 		       pmd_trans_huge(*____pmd));			\
 	} while (0)
+extern void split_huge_page_pmd_mm(struct mm_struct *mm, unsigned long address,
+		pmd_t *pmd);
 #if HPAGE_PMD_ORDER > MAX_ORDER
 #error "hugepages can't be allocated by the buddy allocator"
 #endif
@@ -177,10 +185,12 @@ static inline int split_huge_page(struct page *page)
 {
 	return 0;
 }
-#define split_huge_page_pmd(__mm, __pmd)	\
+#define split_huge_page_pmd(__vma, __address, __pmd)	\
 	do { } while (0)
 #define wait_split_huge_page(__anon_vma, __pmd)	\
 	do { } while (0)
+#define split_huge_page_pmd_mm(__mm, __address, __pmd)	\
+	do { } while (0)
 #define compound_trans_head(page) compound_head(page)
 static inline int hugepage_madvise(struct vm_area_struct *vma,
 				   unsigned long *vm_flags, int advice)

include/linux/memcontrol.h

@@ -181,7 +181,14 @@ unsigned long mem_cgroup_soft_limit_reclaim(struct zone *zone, int order,
 						gfp_t gfp_mask,
 						unsigned long *total_scanned);
 
-void mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx);
+void __mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx);
+static inline void mem_cgroup_count_vm_event(struct mm_struct *mm,
+					     enum vm_event_item idx)
+{
+	if (mem_cgroup_disabled())
+		return;
+	__mem_cgroup_count_vm_event(mm, idx);
+}
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 void mem_cgroup_split_huge_fixup(struct page *head);
 #endif

include/linux/memory.h

@@ -54,6 +54,7 @@ struct memory_notify {
 	unsigned long start_pfn;
 	unsigned long nr_pages;
 	int status_change_nid_normal;
+	int status_change_nid_high;
 	int status_change_nid;
 };
 

include/linux/mmzone.h

@@ -460,17 +460,44 @@ struct zone {
 	unsigned long		zone_start_pfn;
 
 	/*
-	 * zone_start_pfn, spanned_pages and present_pages are all
-	 * protected by span_seqlock.  It is a seqlock because it has
-	 * to be read outside of zone->lock, and it is done in the main
-	 * allocator path.  But, it is written quite infrequently.
+	 * spanned_pages is the total pages spanned by the zone, including
+	 * holes, which is calculated as:
+	 * 	spanned_pages = zone_end_pfn - zone_start_pfn;
 	 *
-	 * The lock is declared along with zone->lock because it is
+	 * present_pages is physical pages existing within the zone, which
+	 * is calculated as:
+	 *	present_pages = spanned_pages - absent_pages(pags in holes);
+	 *
+	 * managed_pages is present pages managed by the buddy system, which
+	 * is calculated as (reserved_pages includes pages allocated by the
+	 * bootmem allocator):
+	 *	managed_pages = present_pages - reserved_pages;
+	 *
+	 * So present_pages may be used by memory hotplug or memory power
+	 * management logic to figure out unmanaged pages by checking
+	 * (present_pages - managed_pages). And managed_pages should be used
+	 * by page allocator and vm scanner to calculate all kinds of watermarks
+	 * and thresholds.
+	 *
+	 * Locking rules:
+	 *
+	 * zone_start_pfn and spanned_pages are protected by span_seqlock.
+	 * It is a seqlock because it has to be read outside of zone->lock,
+	 * and it is done in the main allocator path.  But, it is written
+	 * quite infrequently.
+	 *
+	 * The span_seq lock is declared along with zone->lock because it is
 	 * frequently read in proximity to zone->lock.  It's good to
 	 * give them a chance of being in the same cacheline.
+	 *
+	 * Write access to present_pages and managed_pages at runtime should
+	 * be protected by lock_memory_hotplug()/unlock_memory_hotplug().
+	 * Any reader who can't tolerant drift of present_pages and
+	 * managed_pages should hold memory hotplug lock to get a stable value.
 	 */
-	unsigned long		spanned_pages;	/* total size, including holes */
-	unsigned long		present_pages;	/* amount of memory (excluding holes) */
+	unsigned long		spanned_pages;
+	unsigned long		present_pages;
+	unsigned long		managed_pages;
 
 	/*
 	 * rarely used fields:

include/linux/nodemask.h

@@ -379,6 +379,11 @@ enum node_states {
 	N_HIGH_MEMORY,		/* The node has regular or high memory */
 #else
 	N_HIGH_MEMORY = N_NORMAL_MEMORY,
+#endif
+#ifdef CONFIG_MOVABLE_NODE
+	N_MEMORY,		/* The node has memory(regular, high, movable) */
+#else
+	N_MEMORY = N_HIGH_MEMORY,
 #endif
 	N_CPU,		/* The node has one or more cpus */
 	NR_NODE_STATES

include/linux/res_counter.h

@@ -74,14 +74,9 @@ ssize_t res_counter_read(struct res_counter *counter, int member,
 		const char __user *buf, size_t nbytes, loff_t *pos,
 		int (*read_strategy)(unsigned long long val, char *s));
 
-typedef int (*write_strategy_fn)(const char *buf, unsigned long long *val);
-
 int res_counter_memparse_write_strategy(const char *buf,
 					unsigned long long *res);
 
-int res_counter_write(struct res_counter *counter, int member,
-		      const char *buffer, write_strategy_fn write_strategy);
-
 /*
  * the field descriptors. one for each member of res_counter
  */

include/linux/vm_event_item.h

@@ -58,6 +58,8 @@ enum vm_event_item { PGPGIN, PGPGOUT, PSWPIN, PSWPOUT,
 		THP_COLLAPSE_ALLOC,
 		THP_COLLAPSE_ALLOC_FAILED,
 		THP_SPLIT,
+		THP_ZERO_PAGE_ALLOC,
+		THP_ZERO_PAGE_ALLOC_FAILED,
 #endif
 		NR_VM_EVENT_ITEMS
 };

init/main.c

@@ -857,7 +857,7 @@ static void __init kernel_init_freeable(void)
 	/*
 	 * init can allocate pages on any node
 	 */
-	set_mems_allowed(node_states[N_HIGH_MEMORY]);
+	set_mems_allowed(node_states[N_MEMORY]);
 	/*
 	 * init can run on any cpu.
 	 */

kernel/cpuset.c

@@ -302,10 +302,10 @@ static void guarantee_online_cpus(const struct cpuset *cs,
  * are online, with memory.  If none are online with memory, walk
  * up the cpuset hierarchy until we find one that does have some
  * online mems.  If we get all the way to the top and still haven't
- * found any online mems, return node_states[N_HIGH_MEMORY].
+ * found any online mems, return node_states[N_MEMORY].
  *
  * One way or another, we guarantee to return some non-empty subset
- * of node_states[N_HIGH_MEMORY].
+ * of node_states[N_MEMORY].
  *
  * Call with callback_mutex held.
  */
@@ -313,14 +313,14 @@ static void guarantee_online_cpus(const struct cpuset *cs,
 static void guarantee_online_mems(const struct cpuset *cs, nodemask_t *pmask)
 {
 	while (cs && !nodes_intersects(cs->mems_allowed,
-					node_states[N_HIGH_MEMORY]))
+					node_states[N_MEMORY]))
 		cs = cs->parent;
 	if (cs)
 		nodes_and(*pmask, cs->mems_allowed,
-					node_states[N_HIGH_MEMORY]);
+					node_states[N_MEMORY]);
 	else
-		*pmask = node_states[N_HIGH_MEMORY];
-	BUG_ON(!nodes_intersects(*pmask, node_states[N_HIGH_MEMORY]));
+		*pmask = node_states[N_MEMORY];
+	BUG_ON(!nodes_intersects(*pmask, node_states[N_MEMORY]));
 }
 
 /*
@@ -1100,7 +1100,7 @@ static int update_nodemask(struct cpuset *cs, struct cpuset *trialcs,
 		return -ENOMEM;
 
 	/*
-	 * top_cpuset.mems_allowed tracks node_stats[N_HIGH_MEMORY];
+	 * top_cpuset.mems_allowed tracks node_stats[N_MEMORY];
 	 * it's read-only
 	 */
 	if (cs == &top_cpuset) {
@@ -1122,7 +1122,7 @@ static int update_nodemask(struct cpuset *cs, struct cpuset *trialcs,
 			goto done;
 
 		if (!nodes_subset(trialcs->mems_allowed,
-				node_states[N_HIGH_MEMORY])) {
+				node_states[N_MEMORY])) {
 			retval =  -EINVAL;
 			goto done;
 		}
@@ -2026,7 +2026,7 @@ static struct cpuset *cpuset_next(struct list_head *queue)
  * before dropping down to the next.  It always processes a node before
  * any of its children.
  *
- * In the case of memory hot-unplug, it will remove nodes from N_HIGH_MEMORY
+ * In the case of memory hot-unplug, it will remove nodes from N_MEMORY
  * if all present pages from a node are offlined.
  */
 static void
@@ -2065,7 +2065,7 @@ scan_cpusets_upon_hotplug(struct cpuset *root, enum hotplug_event event)
 
 			/* Continue past cpusets with all mems online */
 			if (nodes_subset(cp->mems_allowed,
-					node_states[N_HIGH_MEMORY]))
+					node_states[N_MEMORY]))
 				continue;
 
 			oldmems = cp->mems_allowed;
@@ -2073,7 +2073,7 @@ scan_cpusets_upon_hotplug(struct cpuset *root, enum hotplug_event event)
 			/* Remove offline mems from this cpuset. */
 			mutex_lock(&callback_mutex);
 			nodes_and(cp->mems_allowed, cp->mems_allowed,
-						node_states[N_HIGH_MEMORY]);
+						node_states[N_MEMORY]);
 			mutex_unlock(&callback_mutex);
 
 			/* Move tasks from the empty cpuset to a parent */
@@ -2126,8 +2126,8 @@ void cpuset_update_active_cpus(bool cpu_online)
 
 #ifdef CONFIG_MEMORY_HOTPLUG
 /*
- * Keep top_cpuset.mems_allowed tracking node_states[N_HIGH_MEMORY].
- * Call this routine anytime after node_states[N_HIGH_MEMORY] changes.
+ * Keep top_cpuset.mems_allowed tracking node_states[N_MEMORY].
+ * Call this routine anytime after node_states[N_MEMORY] changes.
  * See cpuset_update_active_cpus() for CPU hotplug handling.
  */
 static int cpuset_track_online_nodes(struct notifier_block *self,
@@ -2140,7 +2140,7 @@ static int cpuset_track_online_nodes(struct notifier_block *self,
 	case MEM_ONLINE:
 		oldmems = top_cpuset.mems_allowed;
 		mutex_lock(&callback_mutex);
-		top_cpuset.mems_allowed = node_states[N_HIGH_MEMORY];
+		top_cpuset.mems_allowed = node_states[N_MEMORY];
 		mutex_unlock(&callback_mutex);
 		update_tasks_nodemask(&top_cpuset, &oldmems, NULL);
 		break;
@@ -2169,7 +2169,7 @@ static int cpuset_track_online_nodes(struct notifier_block *self,
 void __init cpuset_init_smp(void)
 {
 	cpumask_copy(top_cpuset.cpus_allowed, cpu_active_mask);
-	top_cpuset.mems_allowed = node_states[N_HIGH_MEMORY];
+	top_cpuset.mems_allowed = node_states[N_MEMORY];
 
 	hotplug_memory_notifier(cpuset_track_online_nodes, 10);
 
@@ -2237,7 +2237,7 @@ void cpuset_init_current_mems_allowed(void)
  *
  * Description: Returns the nodemask_t mems_allowed of the cpuset
  * attached to the specified @tsk.  Guaranteed to return some non-empty
- * subset of node_states[N_HIGH_MEMORY], even if this means going outside the
+ * subset of node_states[N_MEMORY], even if this means going outside the
  * tasks cpuset.
  **/
 

kernel/kthread.c

@@ -428,7 +428,7 @@ int kthreadd(void *unused)
 	set_task_comm(tsk, "kthreadd");
 	ignore_signals(tsk);
 	set_cpus_allowed_ptr(tsk, cpu_all_mask);
-	set_mems_allowed(node_states[N_HIGH_MEMORY]);
+	set_mems_allowed(node_states[N_MEMORY]);
 
 	current->flags |= PF_NOFREEZE;
 

kernel/res_counter.c

@@ -192,25 +192,3 @@ int res_counter_memparse_write_strategy(const char *buf,
 	*res = PAGE_ALIGN(*res);
 	return 0;
 }
-
-int res_counter_write(struct res_counter *counter, int member,
-		      const char *buf, write_strategy_fn write_strategy)
-{
-	char *end;
-	unsigned long flags;
-	unsigned long long tmp, *val;
-
-	if (write_strategy) {
-		if (write_strategy(buf, &tmp))
-			return -EINVAL;
-	} else {
-		tmp = simple_strtoull(buf, &end, 10);
-		if (*end != '\0')
-			return -EINVAL;
-	}
-	spin_lock_irqsave(&counter->lock, flags);
-	val = res_counter_member(counter, member);
-	*val = tmp;
-	spin_unlock_irqrestore(&counter->lock, flags);
-	return 0;
-}

mm/Kconfig

@@ -143,6 +143,14 @@ config NO_BOOTMEM
 config MEMORY_ISOLATION
 	boolean
 
+config MOVABLE_NODE
+	boolean "Enable to assign a node which has only movable memory"
+	depends on HAVE_MEMBLOCK
+	depends on NO_BOOTMEM
+	depends on X86_64
+	depends on NUMA
+	depends on BROKEN
+
 # eventually, we can have this option just 'select SPARSEMEM'
 config MEMORY_HOTPLUG
 	bool "Allow for memory hot-add"

mm/bootmem.c

@@ -229,6 +229,22 @@ static unsigned long __init free_all_bootmem_core(bootmem_data_t *bdata)
 	return count;
 }
 
+static void reset_node_lowmem_managed_pages(pg_data_t *pgdat)
+{
+	struct zone *z;
+
+	/*
+	 * In free_area_init_core(), highmem zone's managed_pages is set to
+	 * present_pages, and bootmem allocator doesn't allocate from highmem
+	 * zones. So there's no need to recalculate managed_pages because all
+	 * highmem pages will be managed by the buddy system. Here highmem
+	 * zone also includes highmem movable zone.
+	 */
+	for (z = pgdat->node_zones; z < pgdat->node_zones + MAX_NR_ZONES; z++)
+		if (!is_highmem(z))
+			z->managed_pages = 0;
+}
+
 /**
  * free_all_bootmem_node - release a node's free pages to the buddy allocator
  * @pgdat: node to be released
@@ -238,6 +254,7 @@ static unsigned long __init free_all_bootmem_core(bootmem_data_t *bdata)
 unsigned long __init free_all_bootmem_node(pg_data_t *pgdat)
 {
 	register_page_bootmem_info_node(pgdat);
+	reset_node_lowmem_managed_pages(pgdat);
 	return free_all_bootmem_core(pgdat->bdata);
 }
 
@@ -250,6 +267,10 @@ unsigned long __init free_all_bootmem(void)
 {
 	unsigned long total_pages = 0;
 	bootmem_data_t *bdata;
+	struct pglist_data *pgdat;
+
+	for_each_online_pgdat(pgdat)
+		reset_node_lowmem_managed_pages(pgdat);
 
 	list_for_each_entry(bdata, &bdata_list, list)
 		total_pages += free_all_bootmem_core(bdata);
@@ -439,12 +460,6 @@ int __init reserve_bootmem(unsigned long addr, unsigned long size,
 	return mark_bootmem(start, end, 1, flags);
 }
 
-int __weak __init reserve_bootmem_generic(unsigned long phys, unsigned long len,
-				   int flags)
-{
-	return reserve_bootmem(phys, len, flags);
-}
-
 static unsigned long __init align_idx(struct bootmem_data *bdata,
 				      unsigned long idx, unsigned long step)
 {
@@ -575,27 +590,6 @@ find_block:
 	return NULL;
 }
 
-static void * __init alloc_arch_preferred_bootmem(bootmem_data_t *bdata,
-					unsigned long size, unsigned long align,
-					unsigned long goal, unsigned long limit)
-{
-	if (WARN_ON_ONCE(slab_is_available()))
-		return kzalloc(size, GFP_NOWAIT);
-
-#ifdef CONFIG_HAVE_ARCH_BOOTMEM
-	{
-		bootmem_data_t *p_bdata;
-
-		p_bdata = bootmem_arch_preferred_node(bdata, size, align,
-							goal, limit);
-		if (p_bdata)
-			return alloc_bootmem_bdata(p_bdata, size, align,
-							goal, limit);
-	}
-#endif
-	return NULL;
-}
-
 static void * __init alloc_bootmem_core(unsigned long size,
 					unsigned long align,
 					unsigned long goal,
@@ -604,9 +598,8 @@ static void * __init alloc_bootmem_core(unsigned long size,
 	bootmem_data_t *bdata;
 	void *region;
 
-	region = alloc_arch_preferred_bootmem(NULL, size, align, goal, limit);
-	if (region)
-		return region;
+	if (WARN_ON_ONCE(slab_is_available()))
+		return kzalloc(size, GFP_NOWAIT);
 
 	list_for_each_entry(bdata, &bdata_list, list) {
 		if (goal && bdata->node_low_pfn <= PFN_DOWN(goal))
@@ -704,11 +697,9 @@ void * __init ___alloc_bootmem_node_nopanic(pg_data_t *pgdat,
 {
 	void *ptr;
 
+	if (WARN_ON_ONCE(slab_is_available()))
+		return kzalloc(size, GFP_NOWAIT);
 again:
-	ptr = alloc_arch_preferred_bootmem(pgdat->bdata, size,
-					   align, goal, limit);
-	if (ptr)
-		return ptr;
 
 	/* do not panic in alloc_bootmem_bdata() */
 	if (limit && goal + size > limit)

mm/compaction.c

@@ -215,60 +215,6 @@ static bool suitable_migration_target(struct page *page)
 	return false;
 }
 
-static void compact_capture_page(struct compact_control *cc)
-{
-	unsigned long flags;
-	int mtype, mtype_low, mtype_high;
-
-	if (!cc->page || *cc->page)
-		return;
-
-	/*
-	 * For MIGRATE_MOVABLE allocations we capture a suitable page ASAP
-	 * regardless of the migratetype of the freelist is is captured from.
-	 * This is fine because the order for a high-order MIGRATE_MOVABLE
-	 * allocation is typically at least a pageblock size and overall
-	 * fragmentation is not impaired. Other allocation types must
-	 * capture pages from their own migratelist because otherwise they
-	 * could pollute other pageblocks like MIGRATE_MOVABLE with
-	 * difficult to move pages and making fragmentation worse overall.
-	 */
-	if (cc->migratetype == MIGRATE_MOVABLE) {
-		mtype_low = 0;
-		mtype_high = MIGRATE_PCPTYPES;
-	} else {
-		mtype_low = cc->migratetype;
-		mtype_high = cc->migratetype + 1;
-	}
-
-	/* Speculatively examine the free lists without zone lock */
-	for (mtype = mtype_low; mtype < mtype_high; mtype++) {
-		int order;
-		for (order = cc->order; order < MAX_ORDER; order++) {
-			struct page *page;
-			struct free_area *area;
-			area = &(cc->zone->free_area[order]);
-			if (list_empty(&area->free_list[mtype]))
-				continue;
-
-			/* Take the lock and attempt capture of the page */
-			if (!compact_trylock_irqsave(&cc->zone->lock, &flags, cc))
-				return;
-			if (!list_empty(&area->free_list[mtype])) {
-				page = list_entry(area->free_list[mtype].next,
-							struct page, lru);
-				if (capture_free_page(page, cc->order, mtype)) {
-					spin_unlock_irqrestore(&cc->zone->lock,
-									flags);
-					*cc->page = page;
-					return;
-				}
-			}
-			spin_unlock_irqrestore(&cc->zone->lock, flags);
-		}
-	}
-}
-
 /*
  * Isolate free pages onto a private freelist. Caller must hold zone->lock.
  * If @strict is true, will abort returning 0 on any invalid PFNs or non-free
@@ -953,6 +899,60 @@ unsigned long compaction_suitable(struct zone *zone, int order)
 	return COMPACT_CONTINUE;
 }
 
+static void compact_capture_page(struct compact_control *cc)
+{
+	unsigned long flags;
+	int mtype, mtype_low, mtype_high;
+
+	if (!cc->page || *cc->page)
+		return;
+
+	/*
+	 * For MIGRATE_MOVABLE allocations we capture a suitable page ASAP
+	 * regardless of the migratetype of the freelist is is captured from.
+	 * This is fine because the order for a high-order MIGRATE_MOVABLE
+	 * allocation is typically at least a pageblock size and overall
+	 * fragmentation is not impaired. Other allocation types must
+	 * capture pages from their own migratelist because otherwise they
+	 * could pollute other pageblocks like MIGRATE_MOVABLE with
+	 * difficult to move pages and making fragmentation worse overall.
+	 */
+	if (cc->migratetype == MIGRATE_MOVABLE) {
+		mtype_low = 0;
+		mtype_high = MIGRATE_PCPTYPES;
+	} else {
+		mtype_low = cc->migratetype;
+		mtype_high = cc->migratetype + 1;
+	}
+
+	/* Speculatively examine the free lists without zone lock */
+	for (mtype = mtype_low; mtype < mtype_high; mtype++) {
+		int order;
+		for (order = cc->order; order < MAX_ORDER; order++) {
+			struct page *page;
+			struct free_area *area;
+			area = &(cc->zone->free_area[order]);
+			if (list_empty(&area->free_list[mtype]))
+				continue;
+
+			/* Take the lock and attempt capture of the page */
+			if (!compact_trylock_irqsave(&cc->zone->lock, &flags, cc))
+				return;
+			if (!list_empty(&area->free_list[mtype])) {
+				page = list_entry(area->free_list[mtype].next,
+							struct page, lru);
+				if (capture_free_page(page, cc->order, mtype)) {
+					spin_unlock_irqrestore(&cc->zone->lock,
+									flags);
+					*cc->page = page;
+					return;
+				}
+			}
+			spin_unlock_irqrestore(&cc->zone->lock, flags);
+		}
+	}
+}
+
 static int compact_zone(struct zone *zone, struct compact_control *cc)
 {
 	int ret;

mm/huge_memory.c

@@ -12,12 +12,14 @@
 #include <linux/mmu_notifier.h>
 #include <linux/rmap.h>
 #include <linux/swap.h>
+#include <linux/shrinker.h>
 #include <linux/mm_inline.h>
 #include <linux/kthread.h>
 #include <linux/khugepaged.h>
 #include <linux/freezer.h>
 #include <linux/mman.h>
 #include <linux/pagemap.h>
+
 #include <asm/tlb.h>
 #include <asm/pgalloc.h>
 #include "internal.h"
@@ -37,7 +39,8 @@ unsigned long transparent_hugepage_flags __read_mostly =
 	(1<<TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG)|
 #endif
 	(1<<TRANSPARENT_HUGEPAGE_DEFRAG_FLAG)|
-	(1<<TRANSPARENT_HUGEPAGE_DEFRAG_KHUGEPAGED_FLAG);
+	(1<<TRANSPARENT_HUGEPAGE_DEFRAG_KHUGEPAGED_FLAG)|
+	(1<<TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG);
 
 /* default scan 8*512 pte (or vmas) every 30 second */
 static unsigned int khugepaged_pages_to_scan __read_mostly = HPAGE_PMD_NR*8;
@@ -159,6 +162,77 @@ static int start_khugepaged(void)
 	return err;
 }
 
+static atomic_t huge_zero_refcount;
+static unsigned long huge_zero_pfn __read_mostly;
+
+static inline bool is_huge_zero_pfn(unsigned long pfn)
+{
+	unsigned long zero_pfn = ACCESS_ONCE(huge_zero_pfn);
+	return zero_pfn && pfn == zero_pfn;
+}
+
+static inline bool is_huge_zero_pmd(pmd_t pmd)
+{
+	return is_huge_zero_pfn(pmd_pfn(pmd));
+}
+
+static unsigned long get_huge_zero_page(void)
+{
+	struct page *zero_page;
+retry:
+	if (likely(atomic_inc_not_zero(&huge_zero_refcount)))
+		return ACCESS_ONCE(huge_zero_pfn);
+
+	zero_page = alloc_pages((GFP_TRANSHUGE | __GFP_ZERO) & ~__GFP_MOVABLE,
+			HPAGE_PMD_ORDER);
+	if (!zero_page) {
+		count_vm_event(THP_ZERO_PAGE_ALLOC_FAILED);
+		return 0;
+	}
+	count_vm_event(THP_ZERO_PAGE_ALLOC);
+	preempt_disable();
+	if (cmpxchg(&huge_zero_pfn, 0, page_to_pfn(zero_page))) {
+		preempt_enable();
+		__free_page(zero_page);
+		goto retry;
+	}
+
+	/* We take additional reference here. It will be put back by shrinker */
+	atomic_set(&huge_zero_refcount, 2);
+	preempt_enable();
+	return ACCESS_ONCE(huge_zero_pfn);
+}
+
+static void put_huge_zero_page(void)
+{
+	/*
+	 * Counter should never go to zero here. Only shrinker can put
+	 * last reference.
+	 */
+	BUG_ON(atomic_dec_and_test(&huge_zero_refcount));
+}
+
+static int shrink_huge_zero_page(struct shrinker *shrink,
+		struct shrink_control *sc)
+{
+	if (!sc->nr_to_scan)
+		/* we can free zero page only if last reference remains */
+		return atomic_read(&huge_zero_refcount) == 1 ? HPAGE_PMD_NR : 0;
+
+	if (atomic_cmpxchg(&huge_zero_refcount, 1, 0) == 1) {
+		unsigned long zero_pfn = xchg(&huge_zero_pfn, 0);
+		BUG_ON(zero_pfn == 0);
+		__free_page(__pfn_to_page(zero_pfn));
+	}
+
+	return 0;
+}
+
+static struct shrinker huge_zero_page_shrinker = {
+	.shrink = shrink_huge_zero_page,
+	.seeks = DEFAULT_SEEKS,
+};
+
 #ifdef CONFIG_SYSFS
 
 static ssize_t double_flag_show(struct kobject *kobj,
@@ -284,6 +358,20 @@ static ssize_t defrag_store(struct kobject *kobj,
 static struct kobj_attribute defrag_attr =
 	__ATTR(defrag, 0644, defrag_show, defrag_store);
 
+static ssize_t use_zero_page_show(struct kobject *kobj,
+		struct kobj_attribute *attr, char *buf)
+{
+	return single_flag_show(kobj, attr, buf,
+				TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG);
+}
+static ssize_t use_zero_page_store(struct kobject *kobj,
+		struct kobj_attribute *attr, const char *buf, size_t count)
+{
+	return single_flag_store(kobj, attr, buf, count,
+				 TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG);
+}
+static struct kobj_attribute use_zero_page_attr =
+	__ATTR(use_zero_page, 0644, use_zero_page_show, use_zero_page_store);
 #ifdef CONFIG_DEBUG_VM
 static ssize_t debug_cow_show(struct kobject *kobj,
 				struct kobj_attribute *attr, char *buf)
@@ -305,6 +393,7 @@ static struct kobj_attribute debug_cow_attr =
 static struct attribute *hugepage_attr[] = {
 	&enabled_attr.attr,
 	&defrag_attr.attr,
+	&use_zero_page_attr.attr,
 #ifdef CONFIG_DEBUG_VM
 	&debug_cow_attr.attr,
 #endif
@@ -550,6 +639,8 @@ static int __init hugepage_init(void)
 		goto out;
 	}
 
+	register_shrinker(&huge_zero_page_shrinker);
+
 	/*
 	 * By default disable transparent hugepages on smaller systems,
 	 * where the extra memory used could hurt more than TLB overhead
@@ -678,6 +769,22 @@ static inline struct page *alloc_hugepage(int defrag)
 }
 #endif
 
+static bool set_huge_zero_page(pgtable_t pgtable, struct mm_struct *mm,
+		struct vm_area_struct *vma, unsigned long haddr, pmd_t *pmd,
+		unsigned long zero_pfn)
+{
+	pmd_t entry;
+	if (!pmd_none(*pmd))
+		return false;
+	entry = pfn_pmd(zero_pfn, vma->vm_page_prot);
+	entry = pmd_wrprotect(entry);
+	entry = pmd_mkhuge(entry);
+	set_pmd_at(mm, haddr, pmd, entry);
+	pgtable_trans_huge_deposit(mm, pgtable);
+	mm->nr_ptes++;
+	return true;
+}
+
 int do_huge_pmd_anonymous_page(struct mm_struct *mm, struct vm_area_struct *vma,
 			       unsigned long address, pmd_t *pmd,
 			       unsigned int flags)
@@ -691,6 +798,30 @@ int do_huge_pmd_anonymous_page(struct mm_struct *mm, struct vm_area_struct *vma,
 			return VM_FAULT_OOM;
 		if (unlikely(khugepaged_enter(vma)))
 			return VM_FAULT_OOM;
+		if (!(flags & FAULT_FLAG_WRITE) &&
+				transparent_hugepage_use_zero_page()) {
+			pgtable_t pgtable;
+			unsigned long zero_pfn;
+			bool set;
+			pgtable = pte_alloc_one(mm, haddr);
+			if (unlikely(!pgtable))
+				return VM_FAULT_OOM;
+			zero_pfn = get_huge_zero_page();
+			if (unlikely(!zero_pfn)) {
+				pte_free(mm, pgtable);
+				count_vm_event(THP_FAULT_FALLBACK);
+				goto out;
+			}
+			spin_lock(&mm->page_table_lock);
+			set = set_huge_zero_page(pgtable, mm, vma, haddr, pmd,
+					zero_pfn);
+			spin_unlock(&mm->page_table_lock);
+			if (!set) {
+				pte_free(mm, pgtable);
+				put_huge_zero_page();
+			}
+			return 0;
+		}
 		page = alloc_hugepage_vma(transparent_hugepage_defrag(vma),
 					  vma, haddr, numa_node_id(), 0);
 		if (unlikely(!page)) {
@@ -755,6 +886,26 @@ int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm,
 		pte_free(dst_mm, pgtable);
 		goto out_unlock;
 	}
+	/*
+	 * mm->page_table_lock is enough to be sure that huge zero pmd is not
+	 * under splitting since we don't split the page itself, only pmd to
+	 * a page table.
+	 */
+	if (is_huge_zero_pmd(pmd)) {
+		unsigned long zero_pfn;
+		bool set;
+		/*
+		 * get_huge_zero_page() will never allocate a new page here,
+		 * since we already have a zero page to copy. It just takes a
+		 * reference.
+		 */
+		zero_pfn = get_huge_zero_page();
+		set = set_huge_zero_page(pgtable, dst_mm, vma, addr, dst_pmd,
+				zero_pfn);
+		BUG_ON(!set); /* unexpected !pmd_none(dst_pmd) */
+		ret = 0;
+		goto out_unlock;
+	}
 	if (unlikely(pmd_trans_splitting(pmd))) {
 		/* split huge page running from under us */
 		spin_unlock(&src_mm->page_table_lock);
@@ -806,6 +957,80 @@ unlock:
 	spin_unlock(&mm->page_table_lock);
 }
 
+static int do_huge_pmd_wp_zero_page_fallback(struct mm_struct *mm,
+		struct vm_area_struct *vma, unsigned long address,
+		pmd_t *pmd, pmd_t orig_pmd, unsigned long haddr)
+{
+	pgtable_t pgtable;
+	pmd_t _pmd;
+	struct page *page;
+	int i, ret = 0;
+	unsigned long mmun_start;	/* For mmu_notifiers */
+	unsigned long mmun_end;		/* For mmu_notifiers */
+
+	page = alloc_page_vma(GFP_HIGHUSER_MOVABLE, vma, address);
+	if (!page) {
+		ret |= VM_FAULT_OOM;
+		goto out;
+	}
+
+	if (mem_cgroup_newpage_charge(page, mm, GFP_KERNEL)) {
+		put_page(page);
+		ret |= VM_FAULT_OOM;
+		goto out;
+	}
+
+	clear_user_highpage(page, address);
+	__SetPageUptodate(page);
+
+	mmun_start = haddr;
+	mmun_end   = haddr + HPAGE_PMD_SIZE;
+	mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end);
+
+	spin_lock(&mm->page_table_lock);
+	if (unlikely(!pmd_same(*pmd, orig_pmd)))
+		goto out_free_page;
+
+	pmdp_clear_flush(vma, haddr, pmd);
+	/* leave pmd empty until pte is filled */
+
+	pgtable = pgtable_trans_huge_withdraw(mm);
+	pmd_populate(mm, &_pmd, pgtable);
+
+	for (i = 0; i < HPAGE_PMD_NR; i++, haddr += PAGE_SIZE) {
+		pte_t *pte, entry;
+		if (haddr == (address & PAGE_MASK)) {
+			entry = mk_pte(page, vma->vm_page_prot);
+			entry = maybe_mkwrite(pte_mkdirty(entry), vma);
+			page_add_new_anon_rmap(page, vma, haddr);
+		} else {
+			entry = pfn_pte(my_zero_pfn(haddr), vma->vm_page_prot);
+			entry = pte_mkspecial(entry);
+		}
+		pte = pte_offset_map(&_pmd, haddr);
+		VM_BUG_ON(!pte_none(*pte));
+		set_pte_at(mm, haddr, pte, entry);
+		pte_unmap(pte);
+	}
+	smp_wmb(); /* make pte visible before pmd */
+	pmd_populate(mm, pmd, pgtable);
+	spin_unlock(&mm->page_table_lock);
+	put_huge_zero_page();
+	inc_mm_counter(mm, MM_ANONPAGES);
+
+	mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
+
+	ret |= VM_FAULT_WRITE;
+out:
+	return ret;
+out_free_page:
+	spin_unlock(&mm->page_table_lock);
+	mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
+	mem_cgroup_uncharge_page(page);
+	put_page(page);
+	goto out;
+}
+
 static int do_huge_pmd_wp_page_fallback(struct mm_struct *mm,
 					struct vm_area_struct *vma,
 					unsigned long address,
@@ -912,19 +1137,21 @@ int do_huge_pmd_wp_page(struct mm_struct *mm, struct vm_area_struct *vma,
 			unsigned long address, pmd_t *pmd, pmd_t orig_pmd)
 {
 	int ret = 0;
-	struct page *page, *new_page;
+	struct page *page = NULL, *new_page;
 	unsigned long haddr;
 	unsigned long mmun_start;	/* For mmu_notifiers */
 	unsigned long mmun_end;		/* For mmu_notifiers */
 
 	VM_BUG_ON(!vma->anon_vma);
+	haddr = address & HPAGE_PMD_MASK;
+	if (is_huge_zero_pmd(orig_pmd))
+		goto alloc;
 	spin_lock(&mm->page_table_lock);
 	if (unlikely(!pmd_same(*pmd, orig_pmd)))
 		goto out_unlock;
 
 	page = pmd_page(orig_pmd);
 	VM_BUG_ON(!PageCompound(page) || !PageHead(page));
-	haddr = address & HPAGE_PMD_MASK;
 	if (page_mapcount(page) == 1) {
 		pmd_t entry;
 		entry = pmd_mkyoung(orig_pmd);
@@ -936,7 +1163,7 @@ int do_huge_pmd_wp_page(struct mm_struct *mm, struct vm_area_struct *vma,
 	}
 	get_page(page);
 	spin_unlock(&mm->page_table_lock);
-
+alloc:
 	if (transparent_hugepage_enabled(vma) &&
 	    !transparent_hugepage_debug_cow())
 		new_page = alloc_hugepage_vma(transparent_hugepage_defrag(vma),
@@ -946,24 +1173,34 @@ int do_huge_pmd_wp_page(struct mm_struct *mm, struct vm_area_struct *vma,
 
 	if (unlikely(!new_page)) {
 		count_vm_event(THP_FAULT_FALLBACK);
-		ret = do_huge_pmd_wp_page_fallback(mm, vma, address,
-						   pmd, orig_pmd, page, haddr);
-		if (ret & VM_FAULT_OOM)
-			split_huge_page(page);
-		put_page(page);
+		if (is_huge_zero_pmd(orig_pmd)) {
+			ret = do_huge_pmd_wp_zero_page_fallback(mm, vma,
+					address, pmd, orig_pmd, haddr);
+		} else {
+			ret = do_huge_pmd_wp_page_fallback(mm, vma, address,
+					pmd, orig_pmd, page, haddr);
+			if (ret & VM_FAULT_OOM)
+				split_huge_page(page);
+			put_page(page);
+		}
 		goto out;
 	}
 	count_vm_event(THP_FAULT_ALLOC);
 
 	if (unlikely(mem_cgroup_newpage_charge(new_page, mm, GFP_KERNEL))) {
 		put_page(new_page);
-		split_huge_page(page);
-		put_page(page);
+		if (page) {
+			split_huge_page(page);
+			put_page(page);
+		}
 		ret |= VM_FAULT_OOM;
 		goto out;
 	}
 
-	copy_user_huge_page(new_page, page, haddr, vma, HPAGE_PMD_NR);
+	if (is_huge_zero_pmd(orig_pmd))
+		clear_huge_page(new_page, haddr, HPAGE_PMD_NR);
+	else
+		copy_user_huge_page(new_page, page, haddr, vma, HPAGE_PMD_NR);
 	__SetPageUptodate(new_page);
 
 	mmun_start = haddr;
@@ -971,7 +1208,8 @@ int do_huge_pmd_wp_page(struct mm_struct *mm, struct vm_area_struct *vma,
 	mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end);
 
 	spin_lock(&mm->page_table_lock);
-	put_page(page);
+	if (page)
+		put_page(page);
 	if (unlikely(!pmd_same(*pmd, orig_pmd))) {
 		spin_unlock(&mm->page_table_lock);
 		mem_cgroup_uncharge_page(new_page);
@@ -979,14 +1217,19 @@ int do_huge_pmd_wp_page(struct mm_struct *mm, struct vm_area_struct *vma,
 		goto out_mn;
 	} else {
 		pmd_t entry;
-		VM_BUG_ON(!PageHead(page));
 		entry = mk_huge_pmd(new_page, vma);
 		pmdp_clear_flush(vma, haddr, pmd);
 		page_add_new_anon_rmap(new_page, vma, haddr);
 		set_pmd_at(mm, haddr, pmd, entry);
 		update_mmu_cache_pmd(vma, address, pmd);
-		page_remove_rmap(page);
-		put_page(page);
+		if (is_huge_zero_pmd(orig_pmd)) {
+			add_mm_counter(mm, MM_ANONPAGES, HPAGE_PMD_NR);
+			put_huge_zero_page();
+		} else {
+			VM_BUG_ON(!PageHead(page));
+			page_remove_rmap(page);
+			put_page(page);
+		}
 		ret |= VM_FAULT_WRITE;
 	}
 	spin_unlock(&mm->page_table_lock);
@@ -1055,15 +1298,21 @@ int zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
 		pmd_t orig_pmd;
 		pgtable = pgtable_trans_huge_withdraw(tlb->mm);
 		orig_pmd = pmdp_get_and_clear(tlb->mm, addr, pmd);
-		page = pmd_page(orig_pmd);
 		tlb_remove_pmd_tlb_entry(tlb, pmd, addr);
-		page_remove_rmap(page);
-		VM_BUG_ON(page_mapcount(page) < 0);
-		add_mm_counter(tlb->mm, MM_ANONPAGES, -HPAGE_PMD_NR);
-		VM_BUG_ON(!PageHead(page));
-		tlb->mm->nr_ptes--;
-		spin_unlock(&tlb->mm->page_table_lock);
-		tlb_remove_page(tlb, page);
+		if (is_huge_zero_pmd(orig_pmd)) {
+			tlb->mm->nr_ptes--;
+			spin_unlock(&tlb->mm->page_table_lock);
+			put_huge_zero_page();
+		} else {
+			page = pmd_page(orig_pmd);
+			page_remove_rmap(page);
+			VM_BUG_ON(page_mapcount(page) < 0);
+			add_mm_counter(tlb->mm, MM_ANONPAGES, -HPAGE_PMD_NR);
+			VM_BUG_ON(!PageHead(page));
+			tlb->mm->nr_ptes--;
+			spin_unlock(&tlb->mm->page_table_lock);
+			tlb_remove_page(tlb, page);
+		}
 		pte_free(tlb->mm, pgtable);
 		ret = 1;
 	}
@@ -1135,6 +1384,7 @@ int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
 		pmd_t entry;
 		entry = pmdp_get_and_clear(mm, addr, pmd);
 		entry = pmd_modify(entry, newprot);
+		BUG_ON(pmd_write(entry));
 		set_pmd_at(mm, addr, pmd, entry);
 		spin_unlock(&vma->vm_mm->page_table_lock);
 		ret = 1;
@@ -1477,6 +1727,7 @@ int split_huge_page(struct page *page)
 	struct anon_vma *anon_vma;
 	int ret = 1;
 
+	BUG_ON(is_huge_zero_pfn(page_to_pfn(page)));
 	BUG_ON(!PageAnon(page));
 	anon_vma = page_lock_anon_vma(page);
 	if (!anon_vma)
@@ -2336,19 +2587,65 @@ static int khugepaged(void *none)
 	return 0;
 }
 
-void __split_huge_page_pmd(struct mm_struct *mm, pmd_t *pmd)
+static void __split_huge_zero_page_pmd(struct vm_area_struct *vma,
+		unsigned long haddr, pmd_t *pmd)
+{
+	struct mm_struct *mm = vma->vm_mm;
+	pgtable_t pgtable;
+	pmd_t _pmd;
+	int i;
+
+	pmdp_clear_flush(vma, haddr, pmd);
+	/* leave pmd empty until pte is filled */
+
+	pgtable = pgtable_trans_huge_withdraw(mm);
+	pmd_populate(mm, &_pmd, pgtable);
+
+	for (i = 0; i < HPAGE_PMD_NR; i++, haddr += PAGE_SIZE) {
+		pte_t *pte, entry;
+		entry = pfn_pte(my_zero_pfn(haddr), vma->vm_page_prot);
+		entry = pte_mkspecial(entry);
+		pte = pte_offset_map(&_pmd, haddr);
+		VM_BUG_ON(!pte_none(*pte));
+		set_pte_at(mm, haddr, pte, entry);
+		pte_unmap(pte);
+	}
+	smp_wmb(); /* make pte visible before pmd */
+	pmd_populate(mm, pmd, pgtable);
+	put_huge_zero_page();
+}
+
+void __split_huge_page_pmd(struct vm_area_struct *vma, unsigned long address,
+		pmd_t *pmd)
 {
 	struct page *page;
+	struct mm_struct *mm = vma->vm_mm;
+	unsigned long haddr = address & HPAGE_PMD_MASK;
+	unsigned long mmun_start;	/* For mmu_notifiers */
+	unsigned long mmun_end;		/* For mmu_notifiers */
+
+	BUG_ON(vma->vm_start > haddr || vma->vm_end < haddr + HPAGE_PMD_SIZE);
 
+	mmun_start = haddr;
+	mmun_end   = haddr + HPAGE_PMD_SIZE;
+	mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end);
 	spin_lock(&mm->page_table_lock);
 	if (unlikely(!pmd_trans_huge(*pmd))) {
 		spin_unlock(&mm->page_table_lock);
+		mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
+		return;
+	}
+	if (is_huge_zero_pmd(*pmd)) {
+		__split_huge_zero_page_pmd(vma, haddr, pmd);
+		spin_unlock(&mm->page_table_lock);
+		mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
 		return;
 	}
 	page = pmd_page(*pmd);
 	VM_BUG_ON(!page_count(page));
 	get_page(page);
 	spin_unlock(&mm->page_table_lock);
+	mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
 
 	split_huge_page(page);
 
@@ -2356,6 +2653,16 @@ void __split_huge_page_pmd(struct mm_struct *mm, pmd_t *pmd)
 	BUG_ON(pmd_trans_huge(*pmd));
 }
 
+void split_huge_page_pmd_mm(struct mm_struct *mm, unsigned long address,
+		pmd_t *pmd)
+{
+	struct vm_area_struct *vma;
+
+	vma = find_vma(mm, address);
+	BUG_ON(vma == NULL);
+	split_huge_page_pmd(vma, address, pmd);
+}
+
 static void split_huge_page_address(struct mm_struct *mm,
 				    unsigned long address)
 {
@@ -2370,7 +2677,7 @@ static void split_huge_page_address(struct mm_struct *mm,
 	 * Caller holds the mmap_sem write mode, so a huge pmd cannot
 	 * materialize from under us.
 	 */
-	split_huge_page_pmd(mm, pmd);
+	split_huge_page_pmd_mm(mm, address, pmd);
 }
 
 void __vma_adjust_trans_huge(struct vm_area_struct *vma,

mm/hugetlb.c

@@ -1057,7 +1057,7 @@ static void return_unused_surplus_pages(struct hstate *h,
 	 * on-line nodes with memory and will handle the hstate accounting.
 	 */
 	while (nr_pages--) {
-		if (!free_pool_huge_page(h, &node_states[N_HIGH_MEMORY], 1))
+		if (!free_pool_huge_page(h, &node_states[N_MEMORY], 1))
 			break;
 	}
 }
@@ -1180,14 +1180,14 @@ static struct page *alloc_huge_page(struct vm_area_struct *vma,
 int __weak alloc_bootmem_huge_page(struct hstate *h)
 {
 	struct huge_bootmem_page *m;
-	int nr_nodes = nodes_weight(node_states[N_HIGH_MEMORY]);
+	int nr_nodes = nodes_weight(node_states[N_MEMORY]);
 
 	while (nr_nodes) {
 		void *addr;
 
 		addr = __alloc_bootmem_node_nopanic(
 				NODE_DATA(hstate_next_node_to_alloc(h,
-						&node_states[N_HIGH_MEMORY])),
+						&node_states[N_MEMORY])),
 				huge_page_size(h), huge_page_size(h), 0);
 
 		if (addr) {
@@ -1259,7 +1259,7 @@ static void __init hugetlb_hstate_alloc_pages(struct hstate *h)
 			if (!alloc_bootmem_huge_page(h))
 				break;
 		} else if (!alloc_fresh_huge_page(h,
-					 &node_states[N_HIGH_MEMORY]))
+					 &node_states[N_MEMORY]))
 			break;
 	}
 	h->max_huge_pages = i;
@@ -1527,7 +1527,7 @@ static ssize_t nr_hugepages_store_common(bool obey_mempolicy,
 		if (!(obey_mempolicy &&
 				init_nodemask_of_mempolicy(nodes_allowed))) {
 			NODEMASK_FREE(nodes_allowed);
-			nodes_allowed = &node_states[N_HIGH_MEMORY];
+			nodes_allowed = &node_states[N_MEMORY];
 		}
 	} else if (nodes_allowed) {
 		/*
@@ -1537,11 +1537,11 @@ static ssize_t nr_hugepages_store_common(bool obey_mempolicy,
 		count += h->nr_huge_pages - h->nr_huge_pages_node[nid];
 		init_nodemask_of_node(nodes_allowed, nid);
 	} else
-		nodes_allowed = &node_states[N_HIGH_MEMORY];
+		nodes_allowed = &node_states[N_MEMORY];
 
 	h->max_huge_pages = set_max_huge_pages(h, count, nodes_allowed);
 
-	if (nodes_allowed != &node_states[N_HIGH_MEMORY])
+	if (nodes_allowed != &node_states[N_MEMORY])
 		NODEMASK_FREE(nodes_allowed);
 
 	return len;
@@ -1844,7 +1844,7 @@ static void hugetlb_register_all_nodes(void)
 {
 	int nid;
 
-	for_each_node_state(nid, N_HIGH_MEMORY) {
+	for_each_node_state(nid, N_MEMORY) {
 		struct node *node = node_devices[nid];
 		if (node->dev.id == nid)
 			hugetlb_register_node(node);
@@ -1939,8 +1939,8 @@ void __init hugetlb_add_hstate(unsigned order)
 	for (i = 0; i < MAX_NUMNODES; ++i)
 		INIT_LIST_HEAD(&h->hugepage_freelists[i]);
 	INIT_LIST_HEAD(&h->hugepage_activelist);
-	h->next_nid_to_alloc = first_node(node_states[N_HIGH_MEMORY]);
-	h->next_nid_to_free = first_node(node_states[N_HIGH_MEMORY]);
+	h->next_nid_to_alloc = first_node(node_states[N_MEMORY]);
+	h->next_nid_to_free = first_node(node_states[N_MEMORY]);
 	snprintf(h->name, HSTATE_NAME_LEN, "hugepages-%lukB",
 					huge_page_size(h)/1024);
 	/*
@@ -2035,11 +2035,11 @@ static int hugetlb_sysctl_handler_common(bool obey_mempolicy,
 		if (!(obey_mempolicy &&
 			       init_nodemask_of_mempolicy(nodes_allowed))) {
 			NODEMASK_FREE(nodes_allowed);
-			nodes_allowed = &node_states[N_HIGH_MEMORY];
+			nodes_allowed = &node_states[N_MEMORY];
 		}
 		h->max_huge_pages = set_max_huge_pages(h, tmp, nodes_allowed);
 
-		if (nodes_allowed != &node_states[N_HIGH_MEMORY])
+		if (nodes_allowed != &node_states[N_MEMORY])
 			NODEMASK_FREE(nodes_allowed);
 	}
 out:
@@ -2386,8 +2386,10 @@ again:
 		/*
 		 * HWPoisoned hugepage is already unmapped and dropped reference
 		 */
-		if (unlikely(is_hugetlb_entry_hwpoisoned(pte)))
+		if (unlikely(is_hugetlb_entry_hwpoisoned(pte))) {
+			pte_clear(mm, address, ptep);
 			continue;
+		}
 
 		page = pte_page(pte);
 		/*
@@ -3170,7 +3172,13 @@ int dequeue_hwpoisoned_huge_page(struct page *hpage)
 
 	spin_lock(&hugetlb_lock);
 	if (is_hugepage_on_freelist(hpage)) {
-		list_del(&hpage->lru);
+		/*
+		 * Hwpoisoned hugepage isn't linked to activelist or freelist,
+		 * but dangling hpage->lru can trigger list-debug warnings
+		 * (this happens when we call unpoison_memory() on it),
+		 * so let it point to itself with list_del_init().
+		 */
+		list_del_init(&hpage->lru);
 		set_page_refcounted(hpage);
 		h->free_huge_pages--;
 		h->free_huge_pages_node[nid]--;

mm/memcontrol.c

@@ -59,6 +59,8 @@
 #include <trace/events/vmscan.h>
 
 struct cgroup_subsys mem_cgroup_subsys __read_mostly;
+EXPORT_SYMBOL(mem_cgroup_subsys);
+
 #define MEM_CGROUP_RECLAIM_RETRIES	5
 static struct mem_cgroup *root_mem_cgroup __read_mostly;
 
@@ -800,7 +802,7 @@ static unsigned long mem_cgroup_nr_lru_pages(struct mem_cgroup *memcg,
 	int nid;
 	u64 total = 0;
 
-	for_each_node_state(nid, N_HIGH_MEMORY)
+	for_each_node_state(nid, N_MEMORY)
 		total += mem_cgroup_node_nr_lru_pages(memcg, nid, lru_mask);
 	return total;
 }
@@ -1015,13 +1017,10 @@ void mem_cgroup_iter_break(struct mem_cgroup *root,
 	     iter != NULL;				\
 	     iter = mem_cgroup_iter(NULL, iter, NULL))
 
-void mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx)
+void __mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx)
 {
 	struct mem_cgroup *memcg;
 
-	if (!mm)
-		return;
-
 	rcu_read_lock();
 	memcg = mem_cgroup_from_task(rcu_dereference(mm->owner));
 	if (unlikely(!memcg))
@@ -1040,7 +1039,7 @@ void mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx)
 out:
 	rcu_read_unlock();
 }
-EXPORT_SYMBOL(mem_cgroup_count_vm_event);
+EXPORT_SYMBOL(__mem_cgroup_count_vm_event);
 
 /**
  * mem_cgroup_zone_lruvec - get the lru list vector for a zone and memcg
@@ -1644,9 +1643,9 @@ static void mem_cgroup_may_update_nodemask(struct mem_cgroup *memcg)
 		return;
 
 	/* make a nodemask where this memcg uses memory from */
-	memcg->scan_nodes = node_states[N_HIGH_MEMORY];
+	memcg->scan_nodes = node_states[N_MEMORY];
 
-	for_each_node_mask(nid, node_states[N_HIGH_MEMORY]) {
+	for_each_node_mask(nid, node_states[N_MEMORY]) {
 
 		if (!test_mem_cgroup_node_reclaimable(memcg, nid, false))
 			node_clear(nid, memcg->scan_nodes);
@@ -1717,7 +1716,7 @@ static bool mem_cgroup_reclaimable(struct mem_cgroup *memcg, bool noswap)
 	/*
 	 * Check rest of nodes.
 	 */
-	for_each_node_state(nid, N_HIGH_MEMORY) {
+	for_each_node_state(nid, N_MEMORY) {
 		if (node_isset(nid, memcg->scan_nodes))
 			continue;
 		if (test_mem_cgroup_node_reclaimable(memcg, nid, noswap))
@@ -3776,7 +3775,7 @@ static void mem_cgroup_reparent_charges(struct mem_cgroup *memcg)
 		lru_add_drain_all();
 		drain_all_stock_sync(memcg);
 		mem_cgroup_start_move(memcg);
-		for_each_node_state(node, N_HIGH_MEMORY) {
+		for_each_node_state(node, N_MEMORY) {
 			for (zid = 0; zid < MAX_NR_ZONES; zid++) {
 				enum lru_list lru;
 				for_each_lru(lru) {
@@ -4122,7 +4121,7 @@ static int memcg_numa_stat_show(struct cgroup *cont, struct cftype *cft,
 
 	total_nr = mem_cgroup_nr_lru_pages(memcg, LRU_ALL);
 	seq_printf(m, "total=%lu", total_nr);
-	for_each_node_state(nid, N_HIGH_MEMORY) {
+	for_each_node_state(nid, N_MEMORY) {
 		node_nr = mem_cgroup_node_nr_lru_pages(memcg, nid, LRU_ALL);
 		seq_printf(m, " N%d=%lu", nid, node_nr);
 	}
@@ -4130,7 +4129,7 @@ static int memcg_numa_stat_show(struct cgroup *cont, struct cftype *cft,
 
 	file_nr = mem_cgroup_nr_lru_pages(memcg, LRU_ALL_FILE);
 	seq_printf(m, "file=%lu", file_nr);
-	for_each_node_state(nid, N_HIGH_MEMORY) {
+	for_each_node_state(nid, N_MEMORY) {
 		node_nr = mem_cgroup_node_nr_lru_pages(memcg, nid,
 				LRU_ALL_FILE);
 		seq_printf(m, " N%d=%lu", nid, node_nr);
@@ -4139,7 +4138,7 @@ static int memcg_numa_stat_show(struct cgroup *cont, struct cftype *cft,
 
 	anon_nr = mem_cgroup_nr_lru_pages(memcg, LRU_ALL_ANON);
 	seq_printf(m, "anon=%lu", anon_nr);
-	for_each_node_state(nid, N_HIGH_MEMORY) {
+	for_each_node_state(nid, N_MEMORY) {
 		node_nr = mem_cgroup_node_nr_lru_pages(memcg, nid,
 				LRU_ALL_ANON);
 		seq_printf(m, " N%d=%lu", nid, node_nr);
@@ -4148,7 +4147,7 @@ static int memcg_numa_stat_show(struct cgroup *cont, struct cftype *cft,
 
 	unevictable_nr = mem_cgroup_nr_lru_pages(memcg, BIT(LRU_UNEVICTABLE));
 	seq_printf(m, "unevictable=%lu", unevictable_nr);
-	for_each_node_state(nid, N_HIGH_MEMORY) {
+	for_each_node_state(nid, N_MEMORY) {
 		node_nr = mem_cgroup_node_nr_lru_pages(memcg, nid,
 				BIT(LRU_UNEVICTABLE));
 		seq_printf(m, " N%d=%lu", nid, node_nr);

mm/memory.c

@@ -717,20 +717,6 @@ static inline bool is_cow_mapping(vm_flags_t flags)
 	return (flags & (VM_SHARED | VM_MAYWRITE)) == VM_MAYWRITE;
 }
 
-#ifndef is_zero_pfn
-static inline int is_zero_pfn(unsigned long pfn)
-{
-	return pfn == zero_pfn;
-}
-#endif
-
-#ifndef my_zero_pfn
-static inline unsigned long my_zero_pfn(unsigned long addr)
-{
-	return zero_pfn;
-}
-#endif
-
 /*
  * vm_normal_page -- This function gets the "struct page" associated with a pte.
  *
@@ -1250,7 +1236,7 @@ static inline unsigned long zap_pmd_range(struct mmu_gather *tlb,
 					BUG();
 				}
 #endif
-				split_huge_page_pmd(vma->vm_mm, pmd);
+				split_huge_page_pmd(vma, addr, pmd);
 			} else if (zap_huge_pmd(tlb, vma, pmd, addr))
 				goto next;
 			/* fall through */
@@ -1519,7 +1505,7 @@ struct page *follow_page(struct vm_area_struct *vma, unsigned long address,
 	}
 	if (pmd_trans_huge(*pmd)) {
 		if (flags & FOLL_SPLIT) {
-			split_huge_page_pmd(mm, pmd);
+			split_huge_page_pmd(vma, address, pmd);
 			goto split_fallthrough;
 		}
 		spin_lock(&mm->page_table_lock);
@@ -2794,13 +2780,8 @@ unlock:
 oom_free_new:
 	page_cache_release(new_page);
 oom:
-	if (old_page) {
-		if (page_mkwrite) {
-			unlock_page(old_page);
-			page_cache_release(old_page);
-		}
+	if (old_page)
 		page_cache_release(old_page);
-	}
 	return VM_FAULT_OOM;
 
 unwritable_page:

mm/memory_hotplug.c

@@ -106,6 +106,7 @@ static void get_page_bootmem(unsigned long info,  struct page *page,
 void __ref put_page_bootmem(struct page *page)
 {
 	unsigned long type;
+	static DEFINE_MUTEX(ppb_lock);
 
 	type = (unsigned long) page->lru.next;
 	BUG_ON(type < MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE ||
@@ -115,7 +116,14 @@ void __ref put_page_bootmem(struct page *page)
 		ClearPagePrivate(page);
 		set_page_private(page, 0);
 		INIT_LIST_HEAD(&page->lru);
+
+		/*
+		 * Please refer to comment for __free_pages_bootmem()
+		 * for why we serialize here.
+		 */
+		mutex_lock(&ppb_lock);
 		__free_pages_bootmem(page, 0);
+		mutex_unlock(&ppb_lock);
 	}
 
 }
@@ -581,11 +589,19 @@ static int online_pages_range(unsigned long start_pfn, unsigned long nr_pages,
 	return 0;
 }
 
+#ifdef CONFIG_MOVABLE_NODE
+/* when CONFIG_MOVABLE_NODE, we allow online node don't have normal memory */
+static bool can_online_high_movable(struct zone *zone)
+{
+	return true;
+}
+#else /* #ifdef CONFIG_MOVABLE_NODE */
 /* ensure every online node has NORMAL memory */
 static bool can_online_high_movable(struct zone *zone)
 {
 	return node_state(zone_to_nid(zone), N_NORMAL_MEMORY);
 }
+#endif /* #ifdef CONFIG_MOVABLE_NODE */
 
 /* check which state of node_states will be changed when online memory */
 static void node_states_check_changes_online(unsigned long nr_pages,
@@ -595,13 +611,15 @@ static void node_states_check_changes_online(unsigned long nr_pages,
 	enum zone_type zone_last = ZONE_NORMAL;
 
 	/*
-	 * If we have HIGHMEM, node_states[N_NORMAL_MEMORY] contains nodes
-	 * which have 0...ZONE_NORMAL, set zone_last to ZONE_NORMAL.
+	 * If we have HIGHMEM or movable node, node_states[N_NORMAL_MEMORY]
+	 * contains nodes which have zones of 0...ZONE_NORMAL,
+	 * set zone_last to ZONE_NORMAL.
 	 *
-	 * If we don't have HIGHMEM, node_states[N_NORMAL_MEMORY] contains nodes
-	 * which have 0...ZONE_MOVABLE, set zone_last to ZONE_MOVABLE.
+	 * If we don't have HIGHMEM nor movable node,
+	 * node_states[N_NORMAL_MEMORY] contains nodes which have zones of
+	 * 0...ZONE_MOVABLE, set zone_last to ZONE_MOVABLE.
 	 */
-	if (N_HIGH_MEMORY == N_NORMAL_MEMORY)
+	if (N_MEMORY == N_NORMAL_MEMORY)
 		zone_last = ZONE_MOVABLE;
 
 	/*
@@ -615,12 +633,34 @@ static void node_states_check_changes_online(unsigned long nr_pages,
 	else
 		arg->status_change_nid_normal = -1;
 
+#ifdef CONFIG_HIGHMEM
+	/*
+	 * If we have movable node, node_states[N_HIGH_MEMORY]
+	 * contains nodes which have zones of 0...ZONE_HIGHMEM,
+	 * set zone_last to ZONE_HIGHMEM.
+	 *
+	 * If we don't have movable node, node_states[N_NORMAL_MEMORY]
+	 * contains nodes which have zones of 0...ZONE_MOVABLE,
+	 * set zone_last to ZONE_MOVABLE.
+	 */
+	zone_last = ZONE_HIGHMEM;
+	if (N_MEMORY == N_HIGH_MEMORY)
+		zone_last = ZONE_MOVABLE;
+
+	if (zone_idx(zone) <= zone_last && !node_state(nid, N_HIGH_MEMORY))
+		arg->status_change_nid_high = nid;
+	else
+		arg->status_change_nid_high = -1;
+#else
+	arg->status_change_nid_high = arg->status_change_nid_normal;
+#endif
+
 	/*
 	 * if the node don't have memory befor online, we will need to
-	 * set the node to node_states[N_HIGH_MEMORY] after the memory
+	 * set the node to node_states[N_MEMORY] after the memory
 	 * is online.
 	 */
-	if (!node_state(nid, N_HIGH_MEMORY))
+	if (!node_state(nid, N_MEMORY))
 		arg->status_change_nid = nid;
 	else
 		arg->status_change_nid = -1;
@@ -631,7 +671,10 @@ static void node_states_set_node(int node, struct memory_notify *arg)
 	if (arg->status_change_nid_normal >= 0)
 		node_set_state(node, N_NORMAL_MEMORY);
 
-	node_set_state(node, N_HIGH_MEMORY);
+	if (arg->status_change_nid_high >= 0)
+		node_set_state(node, N_HIGH_MEMORY);
+
+	node_set_state(node, N_MEMORY);
 }
 
 
@@ -713,6 +756,7 @@ int __ref online_pages(unsigned long pfn, unsigned long nr_pages, int online_typ
 		return ret;
 	}
 
+	zone->managed_pages += onlined_pages;
 	zone->present_pages += onlined_pages;
 	zone->zone_pgdat->node_present_pages += onlined_pages;
 	if (onlined_pages) {
@@ -1066,6 +1110,13 @@ check_pages_isolated(unsigned long start_pfn, unsigned long end_pfn)
 	return offlined;
 }
 
+#ifdef CONFIG_MOVABLE_NODE
+/* when CONFIG_MOVABLE_NODE, we allow online node don't have normal memory */
+static bool can_offline_normal(struct zone *zone, unsigned long nr_pages)
+{
+	return true;
+}
+#else /* #ifdef CONFIG_MOVABLE_NODE */
 /* ensure the node has NORMAL memory if it is still online */
 static bool can_offline_normal(struct zone *zone, unsigned long nr_pages)
 {
@@ -1089,6 +1140,7 @@ static bool can_offline_normal(struct zone *zone, unsigned long nr_pages)
 	 */
 	return present_pages == 0;
 }
+#endif /* #ifdef CONFIG_MOVABLE_NODE */
 
 /* check which state of node_states will be changed when offline memory */
 static void node_states_check_changes_offline(unsigned long nr_pages,
@@ -1099,13 +1151,15 @@ static void node_states_check_changes_offline(unsigned long nr_pages,
 	enum zone_type zt, zone_last = ZONE_NORMAL;
 
 	/*
-	 * If we have HIGHMEM, node_states[N_NORMAL_MEMORY] contains nodes
-	 * which have 0...ZONE_NORMAL, set zone_last to ZONE_NORMAL.
+	 * If we have HIGHMEM or movable node, node_states[N_NORMAL_MEMORY]
+	 * contains nodes which have zones of 0...ZONE_NORMAL,
+	 * set zone_last to ZONE_NORMAL.
 	 *
-	 * If we don't have HIGHMEM, node_states[N_NORMAL_MEMORY] contains nodes
-	 * which have 0...ZONE_MOVABLE, set zone_last to ZONE_MOVABLE.
+	 * If we don't have HIGHMEM nor movable node,
+	 * node_states[N_NORMAL_MEMORY] contains nodes which have zones of
+	 * 0...ZONE_MOVABLE, set zone_last to ZONE_MOVABLE.
 	 */
-	if (N_HIGH_MEMORY == N_NORMAL_MEMORY)
+	if (N_MEMORY == N_NORMAL_MEMORY)
 		zone_last = ZONE_MOVABLE;
 
 	/*
@@ -1122,6 +1176,30 @@ static void node_states_check_changes_offline(unsigned long nr_pages,
 	else
 		arg->status_change_nid_normal = -1;
 
+#ifdef CONFIG_HIGHMEM
+	/*
+	 * If we have movable node, node_states[N_HIGH_MEMORY]
+	 * contains nodes which have zones of 0...ZONE_HIGHMEM,
+	 * set zone_last to ZONE_HIGHMEM.
+	 *
+	 * If we don't have movable node, node_states[N_NORMAL_MEMORY]
+	 * contains nodes which have zones of 0...ZONE_MOVABLE,
+	 * set zone_last to ZONE_MOVABLE.
+	 */
+	zone_last = ZONE_HIGHMEM;
+	if (N_MEMORY == N_HIGH_MEMORY)
+		zone_last = ZONE_MOVABLE;
+
+	for (; zt <= zone_last; zt++)
+		present_pages += pgdat->node_zones[zt].present_pages;
+	if (zone_idx(zone) <= zone_last && nr_pages >= present_pages)
+		arg->status_change_nid_high = zone_to_nid(zone);
+	else
+		arg->status_change_nid_high = -1;
+#else
+	arg->status_change_nid_high = arg->status_change_nid_normal;
+#endif
+
 	/*
 	 * node_states[N_HIGH_MEMORY] contains nodes which have 0...ZONE_MOVABLE
 	 */
@@ -1146,9 +1224,13 @@ static void node_states_clear_node(int node, struct memory_notify *arg)
 	if (arg->status_change_nid_normal >= 0)
 		node_clear_state(node, N_NORMAL_MEMORY);
 
-	if ((N_HIGH_MEMORY != N_NORMAL_MEMORY) &&
-	    (arg->status_change_nid >= 0))
+	if ((N_MEMORY != N_NORMAL_MEMORY) &&
+	    (arg->status_change_nid_high >= 0))
 		node_clear_state(node, N_HIGH_MEMORY);
+
+	if ((N_MEMORY != N_HIGH_MEMORY) &&
+	    (arg->status_change_nid >= 0))
+		node_clear_state(node, N_MEMORY);
 }
 
 static int __ref __offline_pages(unsigned long start_pfn,
@@ -1248,6 +1330,7 @@ repeat:
 	/* reset pagetype flags and makes migrate type to be MOVABLE */
 	undo_isolate_page_range(start_pfn, end_pfn, MIGRATE_MOVABLE);
 	/* removal success */
+	zone->managed_pages -= offlined_pages;
 	zone->present_pages -= offlined_pages;
 	zone->zone_pgdat->node_present_pages -= offlined_pages;
 	totalram_pages -= offlined_pages;

mm/mempolicy.c

@@ -212,9 +212,9 @@ static int mpol_set_nodemask(struct mempolicy *pol,
 	/* if mode is MPOL_DEFAULT, pol is NULL. This is right. */
 	if (pol == NULL)
 		return 0;
-	/* Check N_HIGH_MEMORY */
+	/* Check N_MEMORY */
 	nodes_and(nsc->mask1,
-		  cpuset_current_mems_allowed, node_states[N_HIGH_MEMORY]);
+		  cpuset_current_mems_allowed, node_states[N_MEMORY]);
 
 	VM_BUG_ON(!nodes);
 	if (pol->mode == MPOL_PREFERRED && nodes_empty(*nodes))
@@ -511,7 +511,7 @@ static inline int check_pmd_range(struct vm_area_struct *vma, pud_t *pud,
 	pmd = pmd_offset(pud, addr);
 	do {
 		next = pmd_addr_end(addr, end);
-		split_huge_page_pmd(vma->vm_mm, pmd);
+		split_huge_page_pmd(vma, addr, pmd);
 		if (pmd_none_or_trans_huge_or_clear_bad(pmd))
 			continue;
 		if (check_pte_range(vma, pmd, addr, next, nodes,
@@ -1388,7 +1388,7 @@ SYSCALL_DEFINE4(migrate_pages, pid_t, pid, unsigned long, maxnode,
 		goto out_put;
 	}
 
-	if (!nodes_subset(*new, node_states[N_HIGH_MEMORY])) {
+	if (!nodes_subset(*new, node_states[N_MEMORY])) {
 		err = -EINVAL;
 		goto out_put;
 	}
@@ -2326,7 +2326,7 @@ void __init numa_policy_init(void)
 	 * fall back to the largest node if they're all smaller.
 	 */
 	nodes_clear(interleave_nodes);
-	for_each_node_state(nid, N_HIGH_MEMORY) {
+	for_each_node_state(nid, N_MEMORY) {
 		unsigned long total_pages = node_present_pages(nid);
 
 		/* Preserve the largest node */
@@ -2407,7 +2407,7 @@ int mpol_parse_str(char *str, struct mempolicy **mpol, int no_context)
 		*nodelist++ = '\0';
 		if (nodelist_parse(nodelist, nodes))
 			goto out;
-		if (!nodes_subset(nodes, node_states[N_HIGH_MEMORY]))
+		if (!nodes_subset(nodes, node_states[N_MEMORY]))
 			goto out;
 	} else
 		nodes_clear(nodes);
@@ -2441,7 +2441,7 @@ int mpol_parse_str(char *str, struct mempolicy **mpol, int no_context)
 		 * Default to online nodes with memory if no nodelist
 		 */
 		if (!nodelist)
-			nodes = node_states[N_HIGH_MEMORY];
+			nodes = node_states[N_MEMORY];
 		break;
 	case MPOL_LOCAL:
 		/*

mm/migrate.c

@@ -1238,7 +1238,7 @@ static int do_pages_move(struct mm_struct *mm, nodemask_t task_nodes,
 			if (node < 0 || node >= MAX_NUMNODES)
 				goto out_pm;
 
-			if (!node_state(node, N_HIGH_MEMORY))
+			if (!node_state(node, N_MEMORY))
 				goto out_pm;
 
 			err = -EACCES;

mm/mmap.c

@@ -1488,7 +1488,11 @@ munmap_back:
 		 *
 		 * Answer: Yes, several device drivers can do it in their
 		 *         f_op->mmap method. -DaveM
+		 * Bug: If addr is changed, prev, rb_link, rb_parent should
+		 *      be updated for vma_link()
 		 */
+		WARN_ON_ONCE(addr != vma->vm_start);
+
 		addr = vma->vm_start;
 		pgoff = vma->vm_pgoff;
 		vm_flags = vma->vm_flags;
@@ -2065,6 +2069,18 @@ int expand_upwards(struct vm_area_struct *vma, unsigned long address)
 		if (vma->vm_pgoff + (size >> PAGE_SHIFT) >= vma->vm_pgoff) {
 			error = acct_stack_growth(vma, size, grow);
 			if (!error) {
+				/*
+				 * vma_gap_update() doesn't support concurrent
+				 * updates, but we only hold a shared mmap_sem
+				 * lock here, so we need to protect against
+				 * concurrent vma expansions.
+				 * vma_lock_anon_vma() doesn't help here, as
+				 * we don't guarantee that all growable vmas
+				 * in a mm share the same root anon vma.
+				 * So, we reuse mm->page_table_lock to guard
+				 * against concurrent vma expansions.
+				 */
+				spin_lock(&vma->vm_mm->page_table_lock);
 				anon_vma_interval_tree_pre_update_vma(vma);
 				vma->vm_end = address;
 				anon_vma_interval_tree_post_update_vma(vma);
@@ -2072,6 +2088,8 @@ int expand_upwards(struct vm_area_struct *vma, unsigned long address)
 					vma_gap_update(vma->vm_next);
 				else
 					vma->vm_mm->highest_vm_end = address;
+				spin_unlock(&vma->vm_mm->page_table_lock);
+
 				perf_event_mmap(vma);
 			}
 		}
@@ -2122,11 +2140,25 @@ int expand_downwards(struct vm_area_struct *vma,
 		if (grow <= vma->vm_pgoff) {
 			error = acct_stack_growth(vma, size, grow);
 			if (!error) {
+				/*
+				 * vma_gap_update() doesn't support concurrent
+				 * updates, but we only hold a shared mmap_sem
+				 * lock here, so we need to protect against
+				 * concurrent vma expansions.
+				 * vma_lock_anon_vma() doesn't help here, as
+				 * we don't guarantee that all growable vmas
+				 * in a mm share the same root anon vma.
+				 * So, we reuse mm->page_table_lock to guard
+				 * against concurrent vma expansions.
+				 */
+				spin_lock(&vma->vm_mm->page_table_lock);
 				anon_vma_interval_tree_pre_update_vma(vma);
 				vma->vm_start = address;
 				vma->vm_pgoff -= grow;
 				anon_vma_interval_tree_post_update_vma(vma);
 				vma_gap_update(vma);
+				spin_unlock(&vma->vm_mm->page_table_lock);
+
 				perf_event_mmap(vma);
 			}
 		}

mm/mprotect.c

@@ -90,7 +90,7 @@ static inline void change_pmd_range(struct vm_area_struct *vma, pud_t *pud,
 		next = pmd_addr_end(addr, end);
 		if (pmd_trans_huge(*pmd)) {
 			if (next - addr != HPAGE_PMD_SIZE)
-				split_huge_page_pmd(vma->vm_mm, pmd);
+				split_huge_page_pmd(vma, addr, pmd);
 			else if (change_huge_pmd(vma, pmd, addr, newprot))
 				continue;
 			/* fall through */

mm/mremap.c

@@ -182,7 +182,7 @@ unsigned long move_page_tables(struct vm_area_struct *vma,
 				need_flush = true;
 				continue;
 			} else if (!err) {
-				split_huge_page_pmd(vma->vm_mm, old_pmd);
+				split_huge_page_pmd(vma, old_addr, old_pmd);
 			}
 			VM_BUG_ON(pmd_trans_huge(*old_pmd));
 		}

mm/nobootmem.c

@@ -137,6 +137,22 @@ unsigned long __init free_low_memory_core_early(int nodeid)
 	return count;
 }
 
+static void reset_node_lowmem_managed_pages(pg_data_t *pgdat)
+{
+	struct zone *z;
+
+	/*
+	 * In free_area_init_core(), highmem zone's managed_pages is set to
+	 * present_pages, and bootmem allocator doesn't allocate from highmem
+	 * zones. So there's no need to recalculate managed_pages because all
+	 * highmem pages will be managed by the buddy system. Here highmem
+	 * zone also includes highmem movable zone.
+	 */
+	for (z = pgdat->node_zones; z < pgdat->node_zones + MAX_NR_ZONES; z++)
+		if (!is_highmem(z))
+			z->managed_pages = 0;
+}
+
 /**
  * free_all_bootmem_node - release a node's free pages to the buddy allocator
  * @pgdat: node to be released
@@ -146,6 +162,7 @@ unsigned long __init free_low_memory_core_early(int nodeid)
 unsigned long __init free_all_bootmem_node(pg_data_t *pgdat)
 {
 	register_page_bootmem_info_node(pgdat);
+	reset_node_lowmem_managed_pages(pgdat);
 
 	/* free_low_memory_core_early(MAX_NUMNODES) will be called later */
 	return 0;
@@ -158,6 +175,11 @@ unsigned long __init free_all_bootmem_node(pg_data_t *pgdat)
  */
 unsigned long __init free_all_bootmem(void)
 {
+	struct pglist_data *pgdat;
+
+	for_each_online_pgdat(pgdat)
+		reset_node_lowmem_managed_pages(pgdat);
+
 	/*
 	 * We need to use MAX_NUMNODES instead of NODE_DATA(0)->node_id
 	 *  because in some case like Node0 doesn't have RAM installed

mm/oom_kill.c

@@ -215,7 +215,7 @@ static enum oom_constraint constrained_alloc(struct zonelist *zonelist,
 	 * the page allocator means a mempolicy is in effect.  Cpuset policy
 	 * is enforced in get_page_from_freelist().
 	 */
-	if (nodemask && !nodes_subset(node_states[N_HIGH_MEMORY], *nodemask)) {
+	if (nodemask && !nodes_subset(node_states[N_MEMORY], *nodemask)) {
 		*totalpages = total_swap_pages;
 		for_each_node_mask(nid, *nodemask)
 			*totalpages += node_spanned_pages(nid);
@@ -591,43 +591,6 @@ void clear_zonelist_oom(struct zonelist *zonelist, gfp_t gfp_mask)
 	spin_unlock(&zone_scan_lock);
 }
 
-/*
- * Try to acquire the oom killer lock for all system zones.  Returns zero if a
- * parallel oom killing is taking place, otherwise locks all zones and returns
- * non-zero.
- */
-static int try_set_system_oom(void)
-{
-	struct zone *zone;
-	int ret = 1;
-
-	spin_lock(&zone_scan_lock);
-	for_each_populated_zone(zone)
-		if (zone_is_oom_locked(zone)) {
-			ret = 0;
-			goto out;
-		}
-	for_each_populated_zone(zone)
-		zone_set_flag(zone, ZONE_OOM_LOCKED);
-out:
-	spin_unlock(&zone_scan_lock);
-	return ret;
-}
-
-/*
- * Clears ZONE_OOM_LOCKED for all system zones so that failed allocation
- * attempts or page faults may now recall the oom killer, if necessary.
- */
-static void clear_system_oom(void)
-{
-	struct zone *zone;
-
-	spin_lock(&zone_scan_lock);
-	for_each_populated_zone(zone)
-		zone_clear_flag(zone, ZONE_OOM_LOCKED);
-	spin_unlock(&zone_scan_lock);
-}
-
 /**
  * out_of_memory - kill the "best" process when we run out of memory
  * @zonelist: zonelist pointer
@@ -708,15 +671,16 @@ out:
 
 /*
  * The pagefault handler calls here because it is out of memory, so kill a
- * memory-hogging task.  If a populated zone has ZONE_OOM_LOCKED set, a parallel
- * oom killing is already in progress so do nothing.  If a task is found with
- * TIF_MEMDIE set, it has been killed so do nothing and allow it to exit.
+ * memory-hogging task.  If any populated zone has ZONE_OOM_LOCKED set, a
+ * parallel oom killing is already in progress so do nothing.
  */
 void pagefault_out_of_memory(void)
 {
-	if (try_set_system_oom()) {
+	struct zonelist *zonelist = node_zonelist(first_online_node,
+						  GFP_KERNEL);
+
+	if (try_set_zonelist_oom(zonelist, GFP_KERNEL)) {
 		out_of_memory(NULL, 0, 0, NULL, false);
-		clear_system_oom();
+		clear_zonelist_oom(zonelist, GFP_KERNEL);
 	}
-	schedule_timeout_killable(1);
 }

mm/page_alloc.c

@@ -89,6 +89,9 @@ nodemask_t node_states[NR_NODE_STATES] __read_mostly = {
 	[N_NORMAL_MEMORY] = { { [0] = 1UL } },
 #ifdef CONFIG_HIGHMEM
 	[N_HIGH_MEMORY] = { { [0] = 1UL } },
+#endif
+#ifdef CONFIG_MOVABLE_NODE
+	[N_MEMORY] = { { [0] = 1UL } },
 #endif
 	[N_CPU] = { { [0] = 1UL } },
 #endif	/* NUMA */
@@ -732,6 +735,13 @@ static void __free_pages_ok(struct page *page, unsigned int order)
 	local_irq_restore(flags);
 }
 
+/*
+ * Read access to zone->managed_pages is safe because it's unsigned long,
+ * but we still need to serialize writers. Currently all callers of
+ * __free_pages_bootmem() except put_page_bootmem() should only be used
+ * at boot time. So for shorter boot time, we shift the burden to
+ * put_page_bootmem() to serialize writers.
+ */
 void __meminit __free_pages_bootmem(struct page *page, unsigned int order)
 {
 	unsigned int nr_pages = 1 << order;
@@ -747,6 +757,7 @@ void __meminit __free_pages_bootmem(struct page *page, unsigned int order)
 		set_page_count(p, 0);
 	}
 
+	page_zone(page)->managed_pages += 1 << order;
 	set_page_refcounted(page);
 	__free_pages(page, order);
 }
@@ -1695,7 +1706,7 @@ bool zone_watermark_ok_safe(struct zone *z, int order, unsigned long mark,
  *
  * If the zonelist cache is present in the passed in zonelist, then
  * returns a pointer to the allowed node mask (either the current
- * tasks mems_allowed, or node_states[N_HIGH_MEMORY].)
+ * tasks mems_allowed, or node_states[N_MEMORY].)
  *
  * If the zonelist cache is not available for this zonelist, does
  * nothing and returns NULL.
@@ -1724,7 +1735,7 @@ static nodemask_t *zlc_setup(struct zonelist *zonelist, int alloc_flags)
 
 	allowednodes = !in_interrupt() && (alloc_flags & ALLOC_CPUSET) ?
 					&cpuset_current_mems_allowed :
-					&node_states[N_HIGH_MEMORY];
+					&node_states[N_MEMORY];
 	return allowednodes;
 }
 
@@ -2981,6 +2992,7 @@ void show_free_areas(unsigned int filter)
 			" isolated(anon):%lukB"
 			" isolated(file):%lukB"
 			" present:%lukB"
+			" managed:%lukB"
 			" mlocked:%lukB"
 			" dirty:%lukB"
 			" writeback:%lukB"
@@ -3010,6 +3022,7 @@ void show_free_areas(unsigned int filter)
 			K(zone_page_state(zone, NR_ISOLATED_ANON)),
 			K(zone_page_state(zone, NR_ISOLATED_FILE)),
 			K(zone->present_pages),
+			K(zone->managed_pages),
 			K(zone_page_state(zone, NR_MLOCK)),
 			K(zone_page_state(zone, NR_FILE_DIRTY)),
 			K(zone_page_state(zone, NR_WRITEBACK)),
@@ -3238,7 +3251,7 @@ static int find_next_best_node(int node, nodemask_t *used_node_mask)
 		return node;
 	}
 
-	for_each_node_state(n, N_HIGH_MEMORY) {
+	for_each_node_state(n, N_MEMORY) {
 
 		/* Don't want a node to appear more than once */
 		if (node_isset(n, *used_node_mask))
@@ -3380,7 +3393,7 @@ static int default_zonelist_order(void)
  	 * local memory, NODE_ORDER may be suitable.
          */
 	average_size = total_size /
-				(nodes_weight(node_states[N_HIGH_MEMORY]) + 1);
+				(nodes_weight(node_states[N_MEMORY]) + 1);
 	for_each_online_node(nid) {
 		low_kmem_size = 0;
 		total_size = 0;
@@ -4476,6 +4489,26 @@ void __init set_pageblock_order(void)
 
 #endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
 
+static unsigned long __paginginit calc_memmap_size(unsigned long spanned_pages,
+						   unsigned long present_pages)
+{
+	unsigned long pages = spanned_pages;
+
+	/*
+	 * Provide a more accurate estimation if there are holes within
+	 * the zone and SPARSEMEM is in use. If there are holes within the
+	 * zone, each populated memory region may cost us one or two extra
+	 * memmap pages due to alignment because memmap pages for each
+	 * populated regions may not naturally algined on page boundary.
+	 * So the (present_pages >> 4) heuristic is a tradeoff for that.
+	 */
+	if (spanned_pages > present_pages + (present_pages >> 4) &&
+	    IS_ENABLED(CONFIG_SPARSEMEM))
+		pages = present_pages;
+
+	return PAGE_ALIGN(pages * sizeof(struct page)) >> PAGE_SHIFT;
+}
+
 /*
  * Set up the zone data structures:
  *   - mark all pages reserved
@@ -4499,48 +4532,56 @@ static void __paginginit free_area_init_core(struct pglist_data *pgdat,
 
 	for (j = 0; j < MAX_NR_ZONES; j++) {
 		struct zone *zone = pgdat->node_zones + j;
-		unsigned long size, realsize, memmap_pages;
+		unsigned long size, realsize, freesize, memmap_pages;
 
 		size = zone_spanned_pages_in_node(nid, j, zones_size);
-		realsize = size - zone_absent_pages_in_node(nid, j,
+		realsize = freesize = size - zone_absent_pages_in_node(nid, j,
 								zholes_size);
 
 		/*
-		 * Adjust realsize so that it accounts for how much memory
+		 * Adjust freesize so that it accounts for how much memory
 		 * is used by this zone for memmap. This affects the watermark
 		 * and per-cpu initialisations
 		 */
-		memmap_pages =
-			PAGE_ALIGN(size * sizeof(struct page)) >> PAGE_SHIFT;
-		if (realsize >= memmap_pages) {
-			realsize -= memmap_pages;
+		memmap_pages = calc_memmap_size(size, realsize);
+		if (freesize >= memmap_pages) {
+			freesize -= memmap_pages;
 			if (memmap_pages)
 				printk(KERN_DEBUG
 				       "  %s zone: %lu pages used for memmap\n",
 				       zone_names[j], memmap_pages);
 		} else
 			printk(KERN_WARNING
-				"  %s zone: %lu pages exceeds realsize %lu\n",
-				zone_names[j], memmap_pages, realsize);
+				"  %s zone: %lu pages exceeds freesize %lu\n",
+				zone_names[j], memmap_pages, freesize);
 
 		/* Account for reserved pages */
-		if (j == 0 && realsize > dma_reserve) {
-			realsize -= dma_reserve;
+		if (j == 0 && freesize > dma_reserve) {
+			freesize -= dma_reserve;
 			printk(KERN_DEBUG "  %s zone: %lu pages reserved\n",
 					zone_names[0], dma_reserve);
 		}
 
 		if (!is_highmem_idx(j))
-			nr_kernel_pages += realsize;
-		nr_all_pages += realsize;
+			nr_kernel_pages += freesize;
+		/* Charge for highmem memmap if there are enough kernel pages */
+		else if (nr_kernel_pages > memmap_pages * 2)
+			nr_kernel_pages -= memmap_pages;
+		nr_all_pages += freesize;
 
 		zone->spanned_pages = size;
-		zone->present_pages = realsize;
+		zone->present_pages = freesize;
+		/*
+		 * Set an approximate value for lowmem here, it will be adjusted
+		 * when the bootmem allocator frees pages into the buddy system.
+		 * And all highmem pages will be managed by the buddy system.
+		 */
+		zone->managed_pages = is_highmem_idx(j) ? realsize : freesize;
 #ifdef CONFIG_NUMA
 		zone->node = nid;
-		zone->min_unmapped_pages = (realsize*sysctl_min_unmapped_ratio)
+		zone->min_unmapped_pages = (freesize*sysctl_min_unmapped_ratio)
 						/ 100;
-		zone->min_slab_pages = (realsize * sysctl_min_slab_ratio) / 100;
+		zone->min_slab_pages = (freesize * sysctl_min_slab_ratio) / 100;
 #endif
 		zone->name = zone_names[j];
 		spin_lock_init(&zone->lock);
@@ -4731,7 +4772,7 @@ unsigned long __init find_min_pfn_with_active_regions(void)
 /*
  * early_calculate_totalpages()
  * Sum pages in active regions for movable zone.
- * Populate N_HIGH_MEMORY for calculating usable_nodes.
+ * Populate N_MEMORY for calculating usable_nodes.
  */
 static unsigned long __init early_calculate_totalpages(void)
 {
@@ -4744,7 +4785,7 @@ static unsigned long __init early_calculate_totalpages(void)
 
 		totalpages += pages;
 		if (pages)
-			node_set_state(nid, N_HIGH_MEMORY);
+			node_set_state(nid, N_MEMORY);
 	}
   	return totalpages;
 }
@@ -4761,9 +4802,9 @@ static void __init find_zone_movable_pfns_for_nodes(void)
 	unsigned long usable_startpfn;
 	unsigned long kernelcore_node, kernelcore_remaining;
 	/* save the state before borrow the nodemask */
-	nodemask_t saved_node_state = node_states[N_HIGH_MEMORY];
+	nodemask_t saved_node_state = node_states[N_MEMORY];
 	unsigned long totalpages = early_calculate_totalpages();
-	int usable_nodes = nodes_weight(node_states[N_HIGH_MEMORY]);
+	int usable_nodes = nodes_weight(node_states[N_MEMORY]);
 
 	/*
 	 * If movablecore was specified, calculate what size of
@@ -4798,7 +4839,7 @@ static void __init find_zone_movable_pfns_for_nodes(void)
 restart:
 	/* Spread kernelcore memory as evenly as possible throughout nodes */
 	kernelcore_node = required_kernelcore / usable_nodes;
-	for_each_node_state(nid, N_HIGH_MEMORY) {
+	for_each_node_state(nid, N_MEMORY) {
 		unsigned long start_pfn, end_pfn;
 
 		/*
@@ -4890,23 +4931,27 @@ restart:
 
 out:
 	/* restore the node_state */
-	node_states[N_HIGH_MEMORY] = saved_node_state;
+	node_states[N_MEMORY] = saved_node_state;
 }
 
-/* Any regular memory on that node ? */
-static void __init check_for_regular_memory(pg_data_t *pgdat)
+/* Any regular or high memory on that node ? */
+static void check_for_memory(pg_data_t *pgdat, int nid)
 {
-#ifdef CONFIG_HIGHMEM
 	enum zone_type zone_type;
 
-	for (zone_type = 0; zone_type <= ZONE_NORMAL; zone_type++) {
+	if (N_MEMORY == N_NORMAL_MEMORY)
+		return;
+
+	for (zone_type = 0; zone_type <= ZONE_MOVABLE - 1; zone_type++) {
 		struct zone *zone = &pgdat->node_zones[zone_type];
 		if (zone->present_pages) {
-			node_set_state(zone_to_nid(zone), N_NORMAL_MEMORY);
+			node_set_state(nid, N_HIGH_MEMORY);
+			if (N_NORMAL_MEMORY != N_HIGH_MEMORY &&
+			    zone_type <= ZONE_NORMAL)
+				node_set_state(nid, N_NORMAL_MEMORY);
 			break;
 		}
 	}
-#endif
 }
 
 /**
@@ -4989,8 +5034,8 @@ void __init free_area_init_nodes(unsigned long *max_zone_pfn)
 
 		/* Any memory on that node */
 		if (pgdat->node_present_pages)
-			node_set_state(nid, N_HIGH_MEMORY);
-		check_for_regular_memory(pgdat);
+			node_set_state(nid, N_MEMORY);
+		check_for_memory(pgdat, nid);
 	}
 }
 
@@ -5727,7 +5772,7 @@ static int __alloc_contig_migrate_range(struct compact_control *cc,
 	unsigned int tries = 0;
 	int ret = 0;
 
-	migrate_prep_local();
+	migrate_prep();
 
 	while (pfn < end || !list_empty(&cc->migratepages)) {
 		if (fatal_signal_pending(current)) {

mm/page_cgroup.c

@@ -274,7 +274,7 @@ void __init page_cgroup_init(void)
 	if (mem_cgroup_disabled())
 		return;
 
-	for_each_node_state(nid, N_HIGH_MEMORY) {
+	for_each_node_state(nid, N_MEMORY) {
 		unsigned long start_pfn, end_pfn;
 
 		start_pfn = node_start_pfn(nid);

mm/pagewalk.c

@@ -58,7 +58,7 @@ again:
 		if (!walk->pte_entry)
 			continue;
 
-		split_huge_page_pmd(walk->mm, pmd);
+		split_huge_page_pmd_mm(walk->mm, addr, pmd);
 		if (pmd_none_or_trans_huge_or_clear_bad(pmd))
 			goto again;
 		err = walk_pte_range(pmd, addr, next, walk);

mm/rmap.c

@@ -1249,12 +1249,14 @@ int try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
 	update_hiwater_rss(mm);
 
 	if (PageHWPoison(page) && !(flags & TTU_IGNORE_HWPOISON)) {
-		if (PageAnon(page))
-			dec_mm_counter(mm, MM_ANONPAGES);
-		else
-			dec_mm_counter(mm, MM_FILEPAGES);
+		if (!PageHuge(page)) {
+			if (PageAnon(page))
+				dec_mm_counter(mm, MM_ANONPAGES);
+			else
+				dec_mm_counter(mm, MM_FILEPAGES);
+		}
 		set_pte_at(mm, address, pte,
-				swp_entry_to_pte(make_hwpoison_entry(page)));
+			   swp_entry_to_pte(make_hwpoison_entry(page)));
 	} else if (PageAnon(page)) {
 		swp_entry_t entry = { .val = page_private(page) };
 

mm/shmem.c

@@ -1715,6 +1715,96 @@ static ssize_t shmem_file_splice_read(struct file *in, loff_t *ppos,
 	return error;
 }
 
+/*
+ * llseek SEEK_DATA or SEEK_HOLE through the radix_tree.
+ */
+static pgoff_t shmem_seek_hole_data(struct address_space *mapping,
+				    pgoff_t index, pgoff_t end, int origin)
+{
+	struct page *page;
+	struct pagevec pvec;
+	pgoff_t indices[PAGEVEC_SIZE];
+	bool done = false;
+	int i;
+
+	pagevec_init(&pvec, 0);
+	pvec.nr = 1;		/* start small: we may be there already */
+	while (!done) {
+		pvec.nr = shmem_find_get_pages_and_swap(mapping, index,
+					pvec.nr, pvec.pages, indices);
+		if (!pvec.nr) {
+			if (origin == SEEK_DATA)
+				index = end;
+			break;
+		}
+		for (i = 0; i < pvec.nr; i++, index++) {
+			if (index < indices[i]) {
+				if (origin == SEEK_HOLE) {
+					done = true;
+					break;
+				}
+				index = indices[i];
+			}
+			page = pvec.pages[i];
+			if (page && !radix_tree_exceptional_entry(page)) {
+				if (!PageUptodate(page))
+					page = NULL;
+			}
+			if (index >= end ||
+			    (page && origin == SEEK_DATA) ||
+			    (!page && origin == SEEK_HOLE)) {
+				done = true;
+				break;
+			}
+		}
+		shmem_deswap_pagevec(&pvec);
+		pagevec_release(&pvec);
+		pvec.nr = PAGEVEC_SIZE;
+		cond_resched();
+	}
+	return index;
+}
+
+static loff_t shmem_file_llseek(struct file *file, loff_t offset, int origin)
+{
+	struct address_space *mapping = file->f_mapping;
+	struct inode *inode = mapping->host;
+	pgoff_t start, end;
+	loff_t new_offset;
+
+	if (origin != SEEK_DATA && origin != SEEK_HOLE)
+		return generic_file_llseek_size(file, offset, origin,
+					MAX_LFS_FILESIZE, i_size_read(inode));
+	mutex_lock(&inode->i_mutex);
+	/* We're holding i_mutex so we can access i_size directly */
+
+	if (offset < 0)
+		offset = -EINVAL;
+	else if (offset >= inode->i_size)
+		offset = -ENXIO;
+	else {
+		start = offset >> PAGE_CACHE_SHIFT;
+		end = (inode->i_size + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
+		new_offset = shmem_seek_hole_data(mapping, start, end, origin);
+		new_offset <<= PAGE_CACHE_SHIFT;
+		if (new_offset > offset) {
+			if (new_offset < inode->i_size)
+				offset = new_offset;
+			else if (origin == SEEK_DATA)
+				offset = -ENXIO;
+			else
+				offset = inode->i_size;
+		}
+	}
+
+	if (offset >= 0 && offset != file->f_pos) {
+		file->f_pos = offset;
+		file->f_version = 0;
+	}
+	mutex_unlock(&inode->i_mutex);
+	return offset;
+}
+
 static long shmem_fallocate(struct file *file, int mode, loff_t offset,
 							 loff_t len)
 {
@@ -2586,7 +2676,7 @@ static const struct address_space_operations shmem_aops = {
 static const struct file_operations shmem_file_operations = {
 	.mmap		= shmem_mmap,
 #ifdef CONFIG_TMPFS
-	.llseek		= generic_file_llseek,
+	.llseek		= shmem_file_llseek,
 	.read		= do_sync_read,
 	.write		= do_sync_write,
 	.aio_read	= shmem_file_aio_read,

mm/vmscan.c

@@ -3131,7 +3131,7 @@ static int __devinit cpu_callback(struct notifier_block *nfb,
 	int nid;
 
 	if (action == CPU_ONLINE || action == CPU_ONLINE_FROZEN) {
-		for_each_node_state(nid, N_HIGH_MEMORY) {
+		for_each_node_state(nid, N_MEMORY) {
 			pg_data_t *pgdat = NODE_DATA(nid);
 			const struct cpumask *mask;
 
@@ -3187,7 +3187,7 @@ static int __init kswapd_init(void)
 	int nid;
 
 	swap_setup();
-	for_each_node_state(nid, N_HIGH_MEMORY)
+	for_each_node_state(nid, N_MEMORY)
  		kswapd_run(nid);
 	hotcpu_notifier(cpu_callback, 0);
 	return 0;

mm/vmstat.c

@@ -801,6 +801,8 @@ const char * const vmstat_text[] = {
 	"thp_collapse_alloc",
 	"thp_collapse_alloc_failed",
 	"thp_split",
+	"thp_zero_page_alloc",
+	"thp_zero_page_alloc_failed",
 #endif
 
 #endif /* CONFIG_VM_EVENTS_COUNTERS */
@@ -930,7 +932,7 @@ static int pagetypeinfo_show(struct seq_file *m, void *arg)
 	pg_data_t *pgdat = (pg_data_t *)arg;
 
 	/* check memoryless node */
-	if (!node_state(pgdat->node_id, N_HIGH_MEMORY))
+	if (!node_state(pgdat->node_id, N_MEMORY))
 		return 0;
 
 	seq_printf(m, "Page block order: %d\n", pageblock_order);
@@ -992,14 +994,16 @@ static void zoneinfo_show_print(struct seq_file *m, pg_data_t *pgdat,
 		   "\n        high     %lu"
 		   "\n        scanned  %lu"
 		   "\n        spanned  %lu"
-		   "\n        present  %lu",
+		   "\n        present  %lu"
+		   "\n        managed  %lu",
 		   zone_page_state(zone, NR_FREE_PAGES),
 		   min_wmark_pages(zone),
 		   low_wmark_pages(zone),
 		   high_wmark_pages(zone),
 		   zone->pages_scanned,
 		   zone->spanned_pages,
-		   zone->present_pages);
+		   zone->present_pages,
+		   zone->managed_pages);
 
 	for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
 		seq_printf(m, "\n    %-12s %lu", vmstat_text[i],
@@ -1292,7 +1296,7 @@ static int unusable_show(struct seq_file *m, void *arg)
 	pg_data_t *pgdat = (pg_data_t *)arg;
 
 	/* check memoryless node */
-	if (!node_state(pgdat->node_id, N_HIGH_MEMORY))
+	if (!node_state(pgdat->node_id, N_MEMORY))
 		return 0;
 
 	walk_zones_in_node(m, pgdat, unusable_show_print);