Merge branch 'sched/urgent' into sched/core to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>

13 files changed, 130 insertions, 70 deletions

diff --git a/mm/compaction.c b/mm/compaction.c
index ccf97b02b85f..8fa254043801 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -852,16 +852,8 @@ isolate_migratepages_range(struct compact_control *cc, unsigned long start_pfn,
 		pfn = isolate_migratepages_block(cc, pfn, block_end_pfn,
 							ISOLATE_UNEVICTABLE);
 
-		/*
-		 * In case of fatal failure, release everything that might
-		 * have been isolated in the previous iteration, and signal
-		 * the failure back to caller.
-		 */
-		if (!pfn) {
-			putback_movable_pages(&cc->migratepages);
-			cc->nr_migratepages = 0;
+		if (!pfn)
 			break;
-		}
 
 		if (cc->nr_migratepages == COMPACT_CLUSTER_MAX)
 			break;
@@ -1741,7 +1733,7 @@ void compaction_unregister_node(struct node *node)
 
 static inline bool kcompactd_work_requested(pg_data_t *pgdat)
 {
-	return pgdat->kcompactd_max_order > 0;
+	return pgdat->kcompactd_max_order > 0 || kthread_should_stop();
 }
 
 static bool kcompactd_node_suitable(pg_data_t *pgdat)
@@ -1805,6 +1797,8 @@ static void kcompactd_do_work(pg_data_t *pgdat)
 		INIT_LIST_HEAD(&cc.freepages);
 		INIT_LIST_HEAD(&cc.migratepages);
 
+		if (kthread_should_stop())
+			return;
 		status = compact_zone(zone, &cc);
 
 		if (zone_watermark_ok(zone, cc.order, low_wmark_pages(zone),
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 86f9f8b82f8e..f7daa7de8f48 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -232,7 +232,7 @@ retry:
 	return READ_ONCE(huge_zero_page);
 }
 
-static void put_huge_zero_page(void)
+void put_huge_zero_page(void)
 {
 	/*
 	 * Counter should never go to zero here. Only shrinker can put
@@ -1684,12 +1684,12 @@ int zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
 	if (vma_is_dax(vma)) {
 		spin_unlock(ptl);
 		if (is_huge_zero_pmd(orig_pmd))
-			put_huge_zero_page();
+			tlb_remove_page(tlb, pmd_page(orig_pmd));
 	} else if (is_huge_zero_pmd(orig_pmd)) {
 		pte_free(tlb->mm, pgtable_trans_huge_withdraw(tlb->mm, pmd));
 		atomic_long_dec(&tlb->mm->nr_ptes);
 		spin_unlock(ptl);
-		put_huge_zero_page();
+		tlb_remove_page(tlb, pmd_page(orig_pmd));
 	} else {
 		struct page *page = pmd_page(orig_pmd);
 		page_remove_rmap(page, true);
@@ -1960,10 +1960,9 @@ int khugepaged_enter_vma_merge(struct vm_area_struct *vma,
 		 * page fault if needed.
 		 */
 		return 0;
-	if (vma->vm_ops)
+	if (vma->vm_ops || (vm_flags & VM_NO_THP))
 		/* khugepaged not yet working on file or special mappings */
 		return 0;
-	VM_BUG_ON_VMA(vm_flags & VM_NO_THP, vma);
 	hstart = (vma->vm_start + ~HPAGE_PMD_MASK) & HPAGE_PMD_MASK;
 	hend = vma->vm_end & HPAGE_PMD_MASK;
 	if (hstart < hend)
@@ -2352,8 +2351,7 @@ static bool hugepage_vma_check(struct vm_area_struct *vma)
 		return false;
 	if (is_vma_temporary_stack(vma))
 		return false;
-	VM_BUG_ON_VMA(vma->vm_flags & VM_NO_THP, vma);
-	return true;
+	return !(vma->vm_flags & VM_NO_THP);
 }
 
 static void collapse_huge_page(struct mm_struct *mm,
@@ -3454,7 +3452,7 @@ next:
 		}
 	}
 
-	pr_info("%lu of %lu THP split", split, total);
+	pr_info("%lu of %lu THP split\n", split, total);
 
 	return 0;
 }
@@ -3465,7 +3463,7 @@ static int __init split_huge_pages_debugfs(void)
 {
 	void *ret;
 
-	ret = debugfs_create_file("split_huge_pages", 0644, NULL, NULL,
+	ret = debugfs_create_file("split_huge_pages", 0200, NULL, NULL,
 			&split_huge_pages_fops);
 	if (!ret)
 		pr_warn("Failed to create split_huge_pages in debugfs");
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 36db05fa8acb..fe787f5c41bd 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -207,6 +207,7 @@ static void mem_cgroup_oom_notify(struct mem_cgroup *memcg);
 /* "mc" and its members are protected by cgroup_mutex */
 static struct move_charge_struct {
 	spinlock_t	  lock; /* for from, to */
+	struct mm_struct  *mm;
 	struct mem_cgroup *from;
 	struct mem_cgroup *to;
 	unsigned long flags;
@@ -4667,6 +4668,8 @@ static void __mem_cgroup_clear_mc(void)
 
 static void mem_cgroup_clear_mc(void)
 {
+	struct mm_struct *mm = mc.mm;
+
 	/*
 	 * we must clear moving_task before waking up waiters at the end of
 	 * task migration.
@@ -4676,7 +4679,10 @@ static void mem_cgroup_clear_mc(void)
 	spin_lock(&mc.lock);
 	mc.from = NULL;
 	mc.to = NULL;
+	mc.mm = NULL;
 	spin_unlock(&mc.lock);
+
+	mmput(mm);
 }
 
 static int mem_cgroup_can_attach(struct cgroup_taskset *tset)
@@ -4733,6 +4739,7 @@ static int mem_cgroup_can_attach(struct cgroup_taskset *tset)
 		VM_BUG_ON(mc.moved_swap);
 
 		spin_lock(&mc.lock);
+		mc.mm = mm;
 		mc.from = from;
 		mc.to = memcg;
 		mc.flags = move_flags;
@@ -4742,8 +4749,9 @@ static int mem_cgroup_can_attach(struct cgroup_taskset *tset)
 		ret = mem_cgroup_precharge_mc(mm);
 		if (ret)
 			mem_cgroup_clear_mc();
+	} else {
+		mmput(mm);
 	}
-	mmput(mm);
 	return ret;
 }
 
@@ -4852,11 +4860,11 @@ put:			/* get_mctgt_type() gets the page */
 	return ret;
 }
 
-static void mem_cgroup_move_charge(struct mm_struct *mm)
+static void mem_cgroup_move_charge(void)
 {
 	struct mm_walk mem_cgroup_move_charge_walk = {
 		.pmd_entry = mem_cgroup_move_charge_pte_range,
-		.mm = mm,
+		.mm = mc.mm,
 	};
 
 	lru_add_drain_all();
@@ -4868,7 +4876,7 @@ static void mem_cgroup_move_charge(struct mm_struct *mm)
 	atomic_inc(&mc.from->moving_account);
 	synchronize_rcu();
 retry:
-	if (unlikely(!down_read_trylock(&mm->mmap_sem))) {
+	if (unlikely(!down_read_trylock(&mc.mm->mmap_sem))) {
 		/*
 		 * Someone who are holding the mmap_sem might be waiting in
 		 * waitq. So we cancel all extra charges, wake up all waiters,
@@ -4885,23 +4893,16 @@ retry:
 	 * additional charge, the page walk just aborts.
 	 */
 	walk_page_range(0, ~0UL, &mem_cgroup_move_charge_walk);
-	up_read(&mm->mmap_sem);
+	up_read(&mc.mm->mmap_sem);
 	atomic_dec(&mc.from->moving_account);
 }
 
-static void mem_cgroup_move_task(struct cgroup_taskset *tset)
+static void mem_cgroup_move_task(void)
 {
-	struct cgroup_subsys_state *css;
-	struct task_struct *p = cgroup_taskset_first(tset, &css);
-	struct mm_struct *mm = get_task_mm(p);
-
-	if (mm) {
-		if (mc.to)
-			mem_cgroup_move_charge(mm);
-		mmput(mm);
-	}
-	if (mc.to)
+	if (mc.to) {
+		mem_cgroup_move_charge();
 		mem_cgroup_clear_mc();
+	}
 }
 #else	/* !CONFIG_MMU */
 static int mem_cgroup_can_attach(struct cgroup_taskset *tset)
@@ -4911,7 +4912,7 @@ static int mem_cgroup_can_attach(struct cgroup_taskset *tset)
 static void mem_cgroup_cancel_attach(struct cgroup_taskset *tset)
 {
 }
-static void mem_cgroup_move_task(struct cgroup_taskset *tset)
+static void mem_cgroup_move_task(void)
 {
 }
 #endif
@@ -5195,7 +5196,7 @@ struct cgroup_subsys memory_cgrp_subsys = {
 	.css_reset = mem_cgroup_css_reset,
 	.can_attach = mem_cgroup_can_attach,
 	.cancel_attach = mem_cgroup_cancel_attach,
-	.attach = mem_cgroup_move_task,
+	.post_attach = mem_cgroup_move_task,
 	.bind = mem_cgroup_bind,
 	.dfl_cftypes = memory_files,
 	.legacy_cftypes = mem_cgroup_legacy_files,
diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index 78f5f2641b91..ca5acee53b7a 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -888,7 +888,15 @@ int get_hwpoison_page(struct page *page)
 		}
 	}
 
-	return get_page_unless_zero(head);
+	if (get_page_unless_zero(head)) {
+		if (head == compound_head(page))
+			return 1;
+
+		pr_info("MCE: %#lx cannot catch tail\n", page_to_pfn(page));
+		put_page(head);
+	}
+
+	return 0;
 }
 EXPORT_SYMBOL_GPL(get_hwpoison_page);
 
diff --git a/mm/memory.c b/mm/memory.c
index 93897f23cc11..52c218e2b724 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -789,6 +789,46 @@ out:
 	return pfn_to_page(pfn);
 }
 
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+struct page *vm_normal_page_pmd(struct vm_area_struct *vma, unsigned long addr,
+				pmd_t pmd)
+{
+	unsigned long pfn = pmd_pfn(pmd);
+
+	/*
+	 * There is no pmd_special() but there may be special pmds, e.g.
+	 * in a direct-access (dax) mapping, so let's just replicate the
+	 * !HAVE_PTE_SPECIAL case from vm_normal_page() here.
+	 */
+	if (unlikely(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP))) {
+		if (vma->vm_flags & VM_MIXEDMAP) {
+			if (!pfn_valid(pfn))
+				return NULL;
+			goto out;
+		} else {
+			unsigned long off;
+			off = (addr - vma->vm_start) >> PAGE_SHIFT;
+			if (pfn == vma->vm_pgoff + off)
+				return NULL;
+			if (!is_cow_mapping(vma->vm_flags))
+				return NULL;
+		}
+	}
+
+	if (is_zero_pfn(pfn))
+		return NULL;
+	if (unlikely(pfn > highest_memmap_pfn))
+		return NULL;
+
+	/*
+	 * NOTE! We still have PageReserved() pages in the page tables.
+	 * eg. VDSO mappings can cause them to exist.
+	 */
+out:
+	return pfn_to_page(pfn);
+}
+#endif
+
 /*
  * copy one vm_area from one task to the other. Assumes the page tables
  * already present in the new task to be cleared in the whole range
@@ -1182,15 +1222,8 @@ static inline unsigned long zap_pmd_range(struct mmu_gather *tlb,
 		next = pmd_addr_end(addr, end);
 		if (pmd_trans_huge(*pmd) || pmd_devmap(*pmd)) {
 			if (next - addr != HPAGE_PMD_SIZE) {
-#ifdef CONFIG_DEBUG_VM
-				if (!rwsem_is_locked(&tlb->mm->mmap_sem)) {
-					pr_err("%s: mmap_sem is unlocked! addr=0x%lx end=0x%lx vma->vm_start=0x%lx vma->vm_end=0x%lx\n",
-						__func__, addr, end,
-						vma->vm_start,
-						vma->vm_end);
-					BUG();
-				}
-#endif
+				VM_BUG_ON_VMA(vma_is_anonymous(vma) &&
+				    !rwsem_is_locked(&tlb->mm->mmap_sem), vma);
 				split_huge_pmd(vma, pmd, addr);
 			} else if (zap_huge_pmd(tlb, vma, pmd, addr))
 				goto next;
diff --git a/mm/migrate.c b/mm/migrate.c
index 6c822a7b27e0..f9dfb18a4eba 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -975,7 +975,13 @@ out:
 		dec_zone_page_state(page, NR_ISOLATED_ANON +
 				page_is_file_cache(page));
 		/* Soft-offlined page shouldn't go through lru cache list */
-		if (reason == MR_MEMORY_FAILURE) {
+		if (reason == MR_MEMORY_FAILURE && rc == MIGRATEPAGE_SUCCESS) {
+			/*
+			 * With this release, we free successfully migrated
+			 * page and set PG_HWPoison on just freed page
+			 * intentionally. Although it's rather weird, it's how
+			 * HWPoison flag works at the moment.
+			 */
 			put_page(page);
 			if (!test_set_page_hwpoison(page))
 				num_poisoned_pages_inc();
diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 999792d35ccc..bc5149d5ec38 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -1910,7 +1910,8 @@ bool wb_over_bg_thresh(struct bdi_writeback *wb)
 	if (gdtc->dirty > gdtc->bg_thresh)
 		return true;
 
-	if (wb_stat(wb, WB_RECLAIMABLE) > __wb_calc_thresh(gdtc))
+	if (wb_stat(wb, WB_RECLAIMABLE) >
+	    wb_calc_thresh(gdtc->wb, gdtc->bg_thresh))
 		return true;
 
 	if (mdtc) {
@@ -1924,7 +1925,8 @@ bool wb_over_bg_thresh(struct bdi_writeback *wb)
 		if (mdtc->dirty > mdtc->bg_thresh)
 			return true;
 
-		if (wb_stat(wb, WB_RECLAIMABLE) > __wb_calc_thresh(mdtc))
+		if (wb_stat(wb, WB_RECLAIMABLE) >
+		    wb_calc_thresh(mdtc->wb, mdtc->bg_thresh))
 			return true;
 	}
 
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 59de90d5d3a3..c1069efcc4d7 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -6485,7 +6485,7 @@ int __meminit init_per_zone_wmark_min(void)
 	setup_per_zone_inactive_ratio();
 	return 0;
 }
-module_init(init_per_zone_wmark_min)
+core_initcall(init_per_zone_wmark_min)
 
 /*
  * min_free_kbytes_sysctl_handler - just a wrapper around proc_dointvec() so
diff --git a/mm/page_io.c b/mm/page_io.c
index cd92e3d67a32..985f23cfa79b 100644
--- a/mm/page_io.c
+++ b/mm/page_io.c
@@ -353,7 +353,11 @@ int swap_readpage(struct page *page)
 
 	ret = bdev_read_page(sis->bdev, swap_page_sector(page), page);
 	if (!ret) {
-		swap_slot_free_notify(page);
+		if (trylock_page(page)) {
+			swap_slot_free_notify(page);
+			unlock_page(page);
+		}
+
 		count_vm_event(PSWPIN);
 		return 0;
 	}
diff --git a/mm/swap.c b/mm/swap.c
index a0bc206b4ac6..03aacbcb013f 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -728,6 +728,11 @@ void release_pages(struct page **pages, int nr, bool cold)
 			zone = NULL;
 		}
 
+		if (is_huge_zero_page(page)) {
+			put_huge_zero_page();
+			continue;
+		}
+
 		page = compound_head(page);
 		if (!put_page_testzero(page))
 			continue;
diff --git a/mm/vmscan.c b/mm/vmscan.c
index b934223eaa45..142cb61f4822 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -2553,7 +2553,7 @@ static bool shrink_zones(struct zonelist *zonelist, struct scan_control *sc)
 		sc->gfp_mask |= __GFP_HIGHMEM;
 
 	for_each_zone_zonelist_nodemask(zone, z, zonelist,
-					requested_highidx, sc->nodemask) {
+					gfp_zone(sc->gfp_mask), sc->nodemask) {
 		enum zone_type classzone_idx;
 
 		if (!populated_zone(zone))
@@ -3318,6 +3318,20 @@ static void kswapd_try_to_sleep(pg_data_t *pgdat, int order,
 	/* Try to sleep for a short interval */
 	if (prepare_kswapd_sleep(pgdat, order, remaining,
 						balanced_classzone_idx)) {
+		/*
+		 * Compaction records what page blocks it recently failed to
+		 * isolate pages from and skips them in the future scanning.
+		 * When kswapd is going to sleep, it is reasonable to assume
+		 * that pages and compaction may succeed so reset the cache.
+		 */
+		reset_isolation_suitable(pgdat);
+
+		/*
+		 * We have freed the memory, now we should compact it to make
+		 * allocation of the requested order possible.
+		 */
+		wakeup_kcompactd(pgdat, order, classzone_idx);
+
 		remaining = schedule_timeout(HZ/10);
 		finish_wait(&pgdat->kswapd_wait, &wait);
 		prepare_to_wait(&pgdat->kswapd_wait, &wait, TASK_INTERRUPTIBLE);
@@ -3341,20 +3355,6 @@ static void kswapd_try_to_sleep(pg_data_t *pgdat, int order,
 		 */
 		set_pgdat_percpu_threshold(pgdat, calculate_normal_threshold);
 
-		/*
-		 * Compaction records what page blocks it recently failed to
-		 * isolate pages from and skips them in the future scanning.
-		 * When kswapd is going to sleep, it is reasonable to assume
-		 * that pages and compaction may succeed so reset the cache.
-		 */
-		reset_isolation_suitable(pgdat);
-
-		/*
-		 * We have freed the memory, now we should compact it to make
-		 * allocation of the requested order possible.
-		 */
-		wakeup_kcompactd(pgdat, order, classzone_idx);
-
 		if (!kthread_should_stop())
 			schedule();
 
diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
index e72efb109fde..fe47fbba995a 100644
--- a/mm/zsmalloc.c
+++ b/mm/zsmalloc.c
@@ -1735,10 +1735,13 @@ static struct page *isolate_source_page(struct size_class *class)
 static unsigned long zs_can_compact(struct size_class *class)
 {
 	unsigned long obj_wasted;
+	unsigned long obj_allocated = zs_stat_get(class, OBJ_ALLOCATED);
+	unsigned long obj_used = zs_stat_get(class, OBJ_USED);
 
-	obj_wasted = zs_stat_get(class, OBJ_ALLOCATED) -
-		zs_stat_get(class, OBJ_USED);
+	if (obj_allocated <= obj_used)
+		return 0;
 
+	obj_wasted = obj_allocated - obj_used;
 	obj_wasted /= get_maxobj_per_zspage(class->size,
 			class->pages_per_zspage);
 
diff --git a/mm/zswap.c b/mm/zswap.c
index 91dad80d068b..de0f119b1780 100644
--- a/mm/zswap.c
+++ b/mm/zswap.c
@@ -170,6 +170,8 @@ static struct zswap_tree *zswap_trees[MAX_SWAPFILES];
 static LIST_HEAD(zswap_pools);
 /* protects zswap_pools list modification */
 static DEFINE_SPINLOCK(zswap_pools_lock);
+/* pool counter to provide unique names to zpool */
+static atomic_t zswap_pools_count = ATOMIC_INIT(0);
 
 /* used by param callback function */
 static bool zswap_init_started;
@@ -565,6 +567,7 @@ static struct zswap_pool *zswap_pool_find_get(char *type, char *compressor)
 static struct zswap_pool *zswap_pool_create(char *type, char *compressor)
 {
 	struct zswap_pool *pool;
+	char name[38]; /* 'zswap' + 32 char (max) num + \0 */
 	gfp_t gfp = __GFP_NORETRY | __GFP_NOWARN | __GFP_KSWAPD_RECLAIM;
 
 	pool = kzalloc(sizeof(*pool), GFP_KERNEL);
@@ -573,7 +576,10 @@ static struct zswap_pool *zswap_pool_create(char *type, char *compressor)
 		return NULL;
 	}
 
-	pool->zpool = zpool_create_pool(type, "zswap", gfp, &zswap_zpool_ops);
+	/* unique name for each pool specifically required by zsmalloc */
+	snprintf(name, 38, "zswap%x", atomic_inc_return(&zswap_pools_count));
+
+	pool->zpool = zpool_create_pool(type, name, gfp, &zswap_zpool_ops);
 	if (!pool->zpool) {
 		pr_err("%s zpool not available\n", type);
 		goto error;