Merge branch 'master' of /home/davem/src/GIT/linux-2.6/

Conflicts:
	arch/sparc/Kconfig

14 files changed, 680 insertions, 544 deletions

diff --git a/mm/Makefile b/mm/Makefile
index 5e0bd642669..147a7a7873c 100644
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -8,7 +8,7 @@ mmu-$(CONFIG_MMU)	:= fremap.o highmem.o madvise.o memory.o mincore.o \
 			   vmalloc.o
 
 obj-y			:= bootmem.o filemap.o mempool.o oom_kill.o fadvise.o \
-			   maccess.o page_alloc.o page-writeback.o pdflush.o \
+			   maccess.o page_alloc.o page-writeback.o \
 			   readahead.o swap.o truncate.o vmscan.o shmem.o \
 			   prio_tree.o util.o mmzone.o vmstat.o backing-dev.o \
 			   page_isolation.o mm_init.o $(mmu-y)
diff --git a/mm/backing-dev.c b/mm/backing-dev.c
index c86edd24429..d3ca0dac111 100644
--- a/mm/backing-dev.c
+++ b/mm/backing-dev.c
@@ -1,8 +1,11 @@
 
 #include <linux/wait.h>
 #include <linux/backing-dev.h>
+#include <linux/kthread.h>
+#include <linux/freezer.h>
 #include <linux/fs.h>
 #include <linux/pagemap.h>
+#include <linux/mm.h>
 #include <linux/sched.h>
 #include <linux/module.h>
 #include <linux/writeback.h>
@@ -14,6 +17,7 @@ void default_unplug_io_fn(struct backing_dev_info *bdi, struct page *page)
 EXPORT_SYMBOL(default_unplug_io_fn);
 
 struct backing_dev_info default_backing_dev_info = {
+	.name		= "default",
 	.ra_pages	= VM_MAX_READAHEAD * 1024 / PAGE_CACHE_SIZE,
 	.state		= 0,
 	.capabilities	= BDI_CAP_MAP_COPY,
@@ -22,6 +26,18 @@ struct backing_dev_info default_backing_dev_info = {
 EXPORT_SYMBOL_GPL(default_backing_dev_info);
 
 static struct class *bdi_class;
+DEFINE_SPINLOCK(bdi_lock);
+LIST_HEAD(bdi_list);
+LIST_HEAD(bdi_pending_list);
+
+static struct task_struct *sync_supers_tsk;
+static struct timer_list sync_supers_timer;
+
+static int bdi_sync_supers(void *);
+static void sync_supers_timer_fn(unsigned long);
+static void arm_supers_timer(void);
+
+static void bdi_add_default_flusher_task(struct backing_dev_info *bdi);
 
 #ifdef CONFIG_DEBUG_FS
 #include <linux/debugfs.h>
@@ -37,9 +53,29 @@ static void bdi_debug_init(void)
 static int bdi_debug_stats_show(struct seq_file *m, void *v)
 {
 	struct backing_dev_info *bdi = m->private;
+	struct bdi_writeback *wb;
 	unsigned long background_thresh;
 	unsigned long dirty_thresh;
 	unsigned long bdi_thresh;
+	unsigned long nr_dirty, nr_io, nr_more_io, nr_wb;
+	struct inode *inode;
+
+	/*
+	 * inode lock is enough here, the bdi->wb_list is protected by
+	 * RCU on the reader side
+	 */
+	nr_wb = nr_dirty = nr_io = nr_more_io = 0;
+	spin_lock(&inode_lock);
+	list_for_each_entry(wb, &bdi->wb_list, list) {
+		nr_wb++;
+		list_for_each_entry(inode, &wb->b_dirty, i_list)
+			nr_dirty++;
+		list_for_each_entry(inode, &wb->b_io, i_list)
+			nr_io++;
+		list_for_each_entry(inode, &wb->b_more_io, i_list)
+			nr_more_io++;
+	}
+	spin_unlock(&inode_lock);
 
 	get_dirty_limits(&background_thresh, &dirty_thresh, &bdi_thresh, bdi);
 
@@ -49,12 +85,22 @@ static int bdi_debug_stats_show(struct seq_file *m, void *v)
 		   "BdiReclaimable:   %8lu kB\n"
 		   "BdiDirtyThresh:   %8lu kB\n"
 		   "DirtyThresh:      %8lu kB\n"
-		   "BackgroundThresh: %8lu kB\n",
+		   "BackgroundThresh: %8lu kB\n"
+		   "WriteBack threads:%8lu\n"
+		   "b_dirty:          %8lu\n"
+		   "b_io:             %8lu\n"
+		   "b_more_io:        %8lu\n"
+		   "bdi_list:         %8u\n"
+		   "state:            %8lx\n"
+		   "wb_mask:          %8lx\n"
+		   "wb_list:          %8u\n"
+		   "wb_cnt:           %8u\n",
 		   (unsigned long) K(bdi_stat(bdi, BDI_WRITEBACK)),
 		   (unsigned long) K(bdi_stat(bdi, BDI_RECLAIMABLE)),
-		   K(bdi_thresh),
-		   K(dirty_thresh),
-		   K(background_thresh));
+		   K(bdi_thresh), K(dirty_thresh),
+		   K(background_thresh), nr_wb, nr_dirty, nr_io, nr_more_io,
+		   !list_empty(&bdi->bdi_list), bdi->state, bdi->wb_mask,
+		   !list_empty(&bdi->wb_list), bdi->wb_cnt);
 #undef K
 
 	return 0;
@@ -185,6 +231,13 @@ static int __init default_bdi_init(void)
 {
 	int err;
 
+	sync_supers_tsk = kthread_run(bdi_sync_supers, NULL, "sync_supers");
+	BUG_ON(IS_ERR(sync_supers_tsk));
+
+	init_timer(&sync_supers_timer);
+	setup_timer(&sync_supers_timer, sync_supers_timer_fn, 0);
+	arm_supers_timer();
+
 	err = bdi_init(&default_backing_dev_info);
 	if (!err)
 		bdi_register(&default_backing_dev_info, NULL, "default");
@@ -193,6 +246,248 @@ static int __init default_bdi_init(void)
 }
 subsys_initcall(default_bdi_init);
 
+static void bdi_wb_init(struct bdi_writeback *wb, struct backing_dev_info *bdi)
+{
+	memset(wb, 0, sizeof(*wb));
+
+	wb->bdi = bdi;
+	wb->last_old_flush = jiffies;
+	INIT_LIST_HEAD(&wb->b_dirty);
+	INIT_LIST_HEAD(&wb->b_io);
+	INIT_LIST_HEAD(&wb->b_more_io);
+}
+
+static void bdi_task_init(struct backing_dev_info *bdi,
+			  struct bdi_writeback *wb)
+{
+	struct task_struct *tsk = current;
+
+	spin_lock(&bdi->wb_lock);
+	list_add_tail_rcu(&wb->list, &bdi->wb_list);
+	spin_unlock(&bdi->wb_lock);
+
+	tsk->flags |= PF_FLUSHER | PF_SWAPWRITE;
+	set_freezable();
+
+	/*
+	 * Our parent may run at a different priority, just set us to normal
+	 */
+	set_user_nice(tsk, 0);
+}
+
+static int bdi_start_fn(void *ptr)
+{
+	struct bdi_writeback *wb = ptr;
+	struct backing_dev_info *bdi = wb->bdi;
+	int ret;
+
+	/*
+	 * Add us to the active bdi_list
+	 */
+	spin_lock(&bdi_lock);
+	list_add(&bdi->bdi_list, &bdi_list);
+	spin_unlock(&bdi_lock);
+
+	bdi_task_init(bdi, wb);
+
+	/*
+	 * Clear pending bit and wakeup anybody waiting to tear us down
+	 */
+	clear_bit(BDI_pending, &bdi->state);
+	smp_mb__after_clear_bit();
+	wake_up_bit(&bdi->state, BDI_pending);
+
+	ret = bdi_writeback_task(wb);
+
+	/*
+	 * Remove us from the list
+	 */
+	spin_lock(&bdi->wb_lock);
+	list_del_rcu(&wb->list);
+	spin_unlock(&bdi->wb_lock);
+
+	/*
+	 * Flush any work that raced with us exiting. No new work
+	 * will be added, since this bdi isn't discoverable anymore.
+	 */
+	if (!list_empty(&bdi->work_list))
+		wb_do_writeback(wb, 1);
+
+	wb->task = NULL;
+	return ret;
+}
+
+int bdi_has_dirty_io(struct backing_dev_info *bdi)
+{
+	return wb_has_dirty_io(&bdi->wb);
+}
+
+static void bdi_flush_io(struct backing_dev_info *bdi)
+{
+	struct writeback_control wbc = {
+		.bdi			= bdi,
+		.sync_mode		= WB_SYNC_NONE,
+		.older_than_this	= NULL,
+		.range_cyclic		= 1,
+		.nr_to_write		= 1024,
+	};
+
+	writeback_inodes_wbc(&wbc);
+}
+
+/*
+ * kupdated() used to do this. We cannot do it from the bdi_forker_task()
+ * or we risk deadlocking on ->s_umount. The longer term solution would be
+ * to implement sync_supers_bdi() or similar and simply do it from the
+ * bdi writeback tasks individually.
+ */
+static int bdi_sync_supers(void *unused)
+{
+	set_user_nice(current, 0);
+
+	while (!kthread_should_stop()) {
+		set_current_state(TASK_INTERRUPTIBLE);
+		schedule();
+
+		/*
+		 * Do this periodically, like kupdated() did before.
+		 */
+		sync_supers();
+	}
+
+	return 0;
+}
+
+static void arm_supers_timer(void)
+{
+	unsigned long next;
+
+	next = msecs_to_jiffies(dirty_writeback_interval * 10) + jiffies;
+	mod_timer(&sync_supers_timer, round_jiffies_up(next));
+}
+
+static void sync_supers_timer_fn(unsigned long unused)
+{
+	wake_up_process(sync_supers_tsk);
+	arm_supers_timer();
+}
+
+static int bdi_forker_task(void *ptr)
+{
+	struct bdi_writeback *me = ptr;
+
+	bdi_task_init(me->bdi, me);
+
+	for (;;) {
+		struct backing_dev_info *bdi, *tmp;
+		struct bdi_writeback *wb;
+
+		/*
+		 * Temporary measure, we want to make sure we don't see
+		 * dirty data on the default backing_dev_info
+		 */
+		if (wb_has_dirty_io(me) || !list_empty(&me->bdi->work_list))
+			wb_do_writeback(me, 0);
+
+		spin_lock(&bdi_lock);
+
+		/*
+		 * Check if any existing bdi's have dirty data without
+		 * a thread registered. If so, set that up.
+		 */
+		list_for_each_entry_safe(bdi, tmp, &bdi_list, bdi_list) {
+			if (bdi->wb.task)
+				continue;
+			if (list_empty(&bdi->work_list) &&
+			    !bdi_has_dirty_io(bdi))
+				continue;
+
+			bdi_add_default_flusher_task(bdi);
+		}
+
+		set_current_state(TASK_INTERRUPTIBLE);
+
+		if (list_empty(&bdi_pending_list)) {
+			unsigned long wait;
+
+			spin_unlock(&bdi_lock);
+			wait = msecs_to_jiffies(dirty_writeback_interval * 10);
+			schedule_timeout(wait);
+			try_to_freeze();
+			continue;
+		}
+
+		__set_current_state(TASK_RUNNING);
+
+		/*
+		 * This is our real job - check for pending entries in
+		 * bdi_pending_list, and create the tasks that got added
+		 */
+		bdi = list_entry(bdi_pending_list.next, struct backing_dev_info,
+				 bdi_list);
+		list_del_init(&bdi->bdi_list);
+		spin_unlock(&bdi_lock);
+
+		wb = &bdi->wb;
+		wb->task = kthread_run(bdi_start_fn, wb, "flush-%s",
+					dev_name(bdi->dev));
+		/*
+		 * If task creation fails, then readd the bdi to
+		 * the pending list and force writeout of the bdi
+		 * from this forker thread. That will free some memory
+		 * and we can try again.
+		 */
+		if (IS_ERR(wb->task)) {
+			wb->task = NULL;
+
+			/*
+			 * Add this 'bdi' to the back, so we get
+			 * a chance to flush other bdi's to free
+			 * memory.
+			 */
+			spin_lock(&bdi_lock);
+			list_add_tail(&bdi->bdi_list, &bdi_pending_list);
+			spin_unlock(&bdi_lock);
+
+			bdi_flush_io(bdi);
+		}
+	}
+
+	return 0;
+}
+
+/*
+ * Add the default flusher task that gets created for any bdi
+ * that has dirty data pending writeout
+ */
+void static bdi_add_default_flusher_task(struct backing_dev_info *bdi)
+{
+	if (!bdi_cap_writeback_dirty(bdi))
+		return;
+
+	if (WARN_ON(!test_bit(BDI_registered, &bdi->state))) {
+		printk(KERN_ERR "bdi %p/%s is not registered!\n",
+							bdi, bdi->name);
+		return;
+	}
+
+	/*
+	 * Check with the helper whether to proceed adding a task. Will only
+	 * abort if we two or more simultanous calls to
+	 * bdi_add_default_flusher_task() occured, further additions will block
+	 * waiting for previous additions to finish.
+	 */
+	if (!test_and_set_bit(BDI_pending, &bdi->state)) {
+		list_move_tail(&bdi->bdi_list, &bdi_pending_list);
+
+		/*
+		 * We are now on the pending list, wake up bdi_forker_task()
+		 * to finish the job and add us back to the active bdi_list
+		 */
+		wake_up_process(default_backing_dev_info.wb.task);
+	}
+}
+
 int bdi_register(struct backing_dev_info *bdi, struct device *parent,
 		const char *fmt, ...)
 {
@@ -211,9 +506,35 @@ int bdi_register(struct backing_dev_info *bdi, struct device *parent,
 		goto exit;
 	}
 
+	spin_lock(&bdi_lock);
+	list_add_tail(&bdi->bdi_list, &bdi_list);
+	spin_unlock(&bdi_lock);
+
 	bdi->dev = dev;
-	bdi_debug_register(bdi, dev_name(dev));
 
+	/*
+	 * Just start the forker thread for our default backing_dev_info,
+	 * and add other bdi's to the list. They will get a thread created
+	 * on-demand when they need it.
+	 */
+	if (bdi_cap_flush_forker(bdi)) {
+		struct bdi_writeback *wb = &bdi->wb;
+
+		wb->task = kthread_run(bdi_forker_task, wb, "bdi-%s",
+						dev_name(dev));
+		if (IS_ERR(wb->task)) {
+			wb->task = NULL;
+			ret = -ENOMEM;
+
+			spin_lock(&bdi_lock);
+			list_del(&bdi->bdi_list);
+			spin_unlock(&bdi_lock);
+			goto exit;
+		}
+	}
+
+	bdi_debug_register(bdi, dev_name(dev));
+	set_bit(BDI_registered, &bdi->state);
 exit:
 	return ret;
 }
@@ -225,9 +546,42 @@ int bdi_register_dev(struct backing_dev_info *bdi, dev_t dev)
 }
 EXPORT_SYMBOL(bdi_register_dev);
 
+/*
+ * Remove bdi from the global list and shutdown any threads we have running
+ */
+static void bdi_wb_shutdown(struct backing_dev_info *bdi)
+{
+	struct bdi_writeback *wb;
+
+	if (!bdi_cap_writeback_dirty(bdi))
+		return;
+
+	/*
+	 * If setup is pending, wait for that to complete first
+	 */
+	wait_on_bit(&bdi->state, BDI_pending, bdi_sched_wait,
+			TASK_UNINTERRUPTIBLE);
+
+	/*
+	 * Make sure nobody finds us on the bdi_list anymore
+	 */
+	spin_lock(&bdi_lock);
+	list_del(&bdi->bdi_list);
+	spin_unlock(&bdi_lock);
+
+	/*
+	 * Finally, kill the kernel threads. We don't need to be RCU
+	 * safe anymore, since the bdi is gone from visibility.
+	 */
+	list_for_each_entry(wb, &bdi->wb_list, list)
+		kthread_stop(wb->task);
+}
+
 void bdi_unregister(struct backing_dev_info *bdi)
 {
 	if (bdi->dev) {
+		if (!bdi_cap_flush_forker(bdi))
+			bdi_wb_shutdown(bdi);
 		bdi_debug_unregister(bdi);
 		device_unregister(bdi->dev);
 		bdi->dev = NULL;
@@ -237,14 +591,25 @@ EXPORT_SYMBOL(bdi_unregister);
 
 int bdi_init(struct backing_dev_info *bdi)
 {
-	int i;
-	int err;
+	int i, err;
 
 	bdi->dev = NULL;
 
 	bdi->min_ratio = 0;
 	bdi->max_ratio = 100;
 	bdi->max_prop_frac = PROP_FRAC_BASE;
+	spin_lock_init(&bdi->wb_lock);
+	INIT_LIST_HEAD(&bdi->bdi_list);
+	INIT_LIST_HEAD(&bdi->wb_list);
+	INIT_LIST_HEAD(&bdi->work_list);
+
+	bdi_wb_init(&bdi->wb, bdi);
+
+	/*
+	 * Just one thread support for now, hard code mask and count
+	 */
+	bdi->wb_mask = 1;
+	bdi->wb_cnt = 1;
 
 	for (i = 0; i < NR_BDI_STAT_ITEMS; i++) {
 		err = percpu_counter_init(&bdi->bdi_stat[i], 0);
@@ -269,6 +634,8 @@ void bdi_destroy(struct backing_dev_info *bdi)
 {
 	int i;
 
+	WARN_ON(bdi_has_dirty_io(bdi));
+
 	bdi_unregister(bdi);
 
 	for (i = 0; i < NR_BDI_STAT_ITEMS; i++)
diff --git a/mm/bootmem.c b/mm/bootmem.c
index 701740c9e81..555d5d2731c 100644
--- a/mm/bootmem.c
+++ b/mm/bootmem.c
@@ -521,7 +521,11 @@ find_block:
 		region = phys_to_virt(PFN_PHYS(bdata->node_min_pfn) +
 				start_off);
 		memset(region, 0, size);
-		kmemleak_alloc(region, size, 1, 0);
+		/*
+		 * The min_count is set to 0 so that bootmem allocated blocks
+		 * are never reported as leaks.
+		 */
+		kmemleak_alloc(region, size, 0, 0);
 		return region;
 	}
 
diff --git a/mm/kmemleak.c b/mm/kmemleak.c
index 487267310a8..4ea4510e299 100644
--- a/mm/kmemleak.c
+++ b/mm/kmemleak.c
@@ -92,11 +92,13 @@
 #include <linux/string.h>
 #include <linux/nodemask.h>
 #include <linux/mm.h>
+#include <linux/workqueue.h>
 
 #include <asm/sections.h>
 #include <asm/processor.h>
 #include <asm/atomic.h>
 
+#include <linux/kmemcheck.h>
 #include <linux/kmemleak.h>
 
 /*
@@ -107,6 +109,7 @@
 #define SECS_FIRST_SCAN		60	/* delay before the first scan */
 #define SECS_SCAN_WAIT		600	/* subsequent auto scanning delay */
 #define GRAY_LIST_PASSES	25	/* maximum number of gray list scans */
+#define MAX_SCAN_SIZE		4096	/* maximum size of a scanned block */
 
 #define BYTES_PER_POINTER	sizeof(void *)
 
@@ -120,6 +123,9 @@ struct kmemleak_scan_area {
 	size_t length;
 };
 
+#define KMEMLEAK_GREY	0
+#define KMEMLEAK_BLACK	-1
+
 /*
  * Structure holding the metadata for each allocated memory block.
  * Modifications to such objects should be made while holding the
@@ -161,6 +167,15 @@ struct kmemleak_object {
 /* flag set on newly allocated objects */
 #define OBJECT_NEW		(1 << 3)
 
+/* number of bytes to print per line; must be 16 or 32 */
+#define HEX_ROW_SIZE		16
+/* number of bytes to print at a time (1, 2, 4, 8) */
+#define HEX_GROUP_SIZE		1
+/* include ASCII after the hex output */
+#define HEX_ASCII		1
+/* max number of lines to be printed */
+#define HEX_MAX_LINES		2
+
 /* the list of all allocated objects */
 static LIST_HEAD(object_list);
 /* the list of gray-colored objects (see color_gray comment below) */
@@ -228,11 +243,14 @@ struct early_log {
 	int min_count;			/* minimum reference count */
 	unsigned long offset;		/* scan area offset */
 	size_t length;			/* scan area length */
+	unsigned long trace[MAX_TRACE];	/* stack trace */
+	unsigned int trace_len;		/* stack trace length */
 };
 
 /* early logging buffer and current position */
-static struct early_log early_log[CONFIG_DEBUG_KMEMLEAK_EARLY_LOG_SIZE];
-static int crt_early_log;
+static struct early_log
+	early_log[CONFIG_DEBUG_KMEMLEAK_EARLY_LOG_SIZE] __initdata;
+static int crt_early_log __initdata;
 
 static void kmemleak_disable(void);
 
@@ -255,6 +273,35 @@ static void kmemleak_disable(void);
 } while (0)
 
 /*
+ * Printing of the objects hex dump to the seq file. The number of lines to be
+ * printed is limited to HEX_MAX_LINES to prevent seq file spamming. The
+ * actual number of printed bytes depends on HEX_ROW_SIZE. It must be called
+ * with the object->lock held.
+ */
+static void hex_dump_object(struct seq_file *seq,
+			    struct kmemleak_object *object)
+{
+	const u8 *ptr = (const u8 *)object->pointer;
+	int i, len, remaining;
+	unsigned char linebuf[HEX_ROW_SIZE * 5];
+
+	/* limit the number of lines to HEX_MAX_LINES */
+	remaining = len =
+		min(object->size, (size_t)(HEX_MAX_LINES * HEX_ROW_SIZE));
+
+	seq_printf(seq, "  hex dump (first %d bytes):\n", len);
+	for (i = 0; i < len; i += HEX_ROW_SIZE) {
+		int linelen = min(remaining, HEX_ROW_SIZE);
+
+		remaining -= HEX_ROW_SIZE;
+		hex_dump_to_buffer(ptr + i, linelen, HEX_ROW_SIZE,
+				   HEX_GROUP_SIZE, linebuf, sizeof(linebuf),
+				   HEX_ASCII);
+		seq_printf(seq, "    %s\n", linebuf);
+	}
+}
+
+/*
  * Object colors, encoded with count and min_count:
  * - white - orphan object, not enough references to it (count < min_count)
  * - gray  - not orphan, not marked as false positive (min_count == 0) or
@@ -264,19 +311,21 @@ static void kmemleak_disable(void);
  * Newly created objects don't have any color assigned (object->count == -1)
  * before the next memory scan when they become white.
  */
-static int color_white(const struct kmemleak_object *object)
+static bool color_white(const struct kmemleak_object *object)
 {
-	return object->count != -1 && object->count < object->min_count;
+	return object->count != KMEMLEAK_BLACK &&
+		object->count < object->min_count;
 }
 
-static int color_gray(const struct kmemleak_object *object)
+static bool color_gray(const struct kmemleak_object *object)
 {
-	return object->min_count != -1 && object->count >= object->min_count;
+	return object->min_count != KMEMLEAK_BLACK &&
+		object->count >= object->min_count;
 }
 
-static int color_black(const struct kmemleak_object *object)
+static bool color_black(const struct kmemleak_object *object)
 {
-	return object->min_count == -1;
+	return object->min_count == KMEMLEAK_BLACK;
 }
 
 /*
@@ -284,7 +333,7 @@ static int color_black(const struct kmemleak_object *object)
  * not be deleted and have a minimum age to avoid false positives caused by
  * pointers temporarily stored in CPU registers.
  */
-static int unreferenced_object(struct kmemleak_object *object)
+static bool unreferenced_object(struct kmemleak_object *object)
 {
 	return (object->flags & OBJECT_ALLOCATED) && color_white(object) &&
 		time_before_eq(object->jiffies + jiffies_min_age,
@@ -304,6 +353,7 @@ static void print_unreferenced(struct seq_file *seq,
 		   object->pointer, object->size);
 	seq_printf(seq, "  comm \"%s\", pid %d, jiffies %lu\n",
 		   object->comm, object->pid, object->jiffies);
+	hex_dump_object(seq, object);
 	seq_printf(seq, "  backtrace:\n");
 
 	for (i = 0; i < object->trace_len; i++) {
@@ -330,6 +380,7 @@ static void dump_object_info(struct kmemleak_object *object)
 		  object->comm, object->pid, object->jiffies);
 	pr_notice("  min_count = %d\n", object->min_count);
 	pr_notice("  count = %d\n", object->count);
+	pr_notice("  flags = 0x%lx\n", object->flags);
 	pr_notice("  backtrace:\n");
 	print_stack_trace(&trace, 4);
 }
@@ -434,21 +485,36 @@ static struct kmemleak_object *find_and_get_object(unsigned long ptr, int alias)
 }
 
 /*
+ * Save stack trace to the given array of MAX_TRACE size.
+ */
+static int __save_stack_trace(unsigned long *trace)
+{
+	struct stack_trace stack_trace;
+
+	stack_trace.max_entries = MAX_TRACE;
+	stack_trace.nr_entries = 0;
+	stack_trace.entries = trace;
+	stack_trace.skip = 2;
+	save_stack_trace(&stack_trace);
+
+	return stack_trace.nr_entries;
+}
+
+/*
  * Create the metadata (struct kmemleak_object) corresponding to an allocated
  * memory block and add it to the object_list and object_tree_root.
  */
-static void create_object(unsigned long ptr, size_t size, int min_count,
-			  gfp_t gfp)
+static struct kmemleak_object *create_object(unsigned long ptr, size_t size,
+					     int min_count, gfp_t gfp)
 {
 	unsigned long flags;
 	struct kmemleak_object *object;
 	struct prio_tree_node *node;
-	struct stack_trace trace;
 
 	object = kmem_cache_alloc(object_cache, gfp & GFP_KMEMLEAK_MASK);
 	if (!object) {
 		kmemleak_stop("Cannot allocate a kmemleak_object structure\n");
-		return;
+		return NULL;
 	}
 
 	INIT_LIST_HEAD(&object->object_list);
@@ -482,18 +548,14 @@ static void create_object(unsigned long ptr, size_t size, int min_count,
 	}
 
 	/* kernel backtrace */
-	trace.max_entries = MAX_TRACE;
-	trace.nr_entries = 0;
-	trace.entries = object->trace;
-	trace.skip = 1;
-	save_stack_trace(&trace);
-	object->trace_len = trace.nr_entries;
+	object->trace_len = __save_stack_trace(object->trace);
 
 	INIT_PRIO_TREE_NODE(&object->tree_node);
 	object->tree_node.start = ptr;
 	object->tree_node.last = ptr + size - 1;
 
 	write_lock_irqsave(&kmemleak_lock, flags);
+
 	min_addr = min(min_addr, ptr);
 	max_addr = max(max_addr, ptr + size);
 	node = prio_tree_insert(&object_tree_root, &object->tree_node);
@@ -504,20 +566,19 @@ static void create_object(unsigned long ptr, size_t size, int min_count,
 	 * random memory blocks.
 	 */
 	if (node != &object->tree_node) {
-		unsigned long flags;
-
 		kmemleak_stop("Cannot insert 0x%lx into the object search tree "
 			      "(already existing)\n", ptr);
 		object = lookup_object(ptr, 1);
-		spin_lock_irqsave(&object->lock, flags);
+		spin_lock(&object->lock);
 		dump_object_info(object);
-		spin_unlock_irqrestore(&object->lock, flags);
+		spin_unlock(&object->lock);
 
 		goto out;
 	}
 	list_add_tail_rcu(&object->object_list, &object_list);
 out:
 	write_unlock_irqrestore(&kmemleak_lock, flags);
+	return object;
 }
 
 /*
@@ -604,46 +665,55 @@ static void delete_object_part(unsigned long ptr, size_t size)
 
 	put_object(object);
 }
-/*
- * Make a object permanently as gray-colored so that it can no longer be
- * reported as a leak. This is used in general to mark a false positive.
- */
-static void make_gray_object(unsigned long ptr)
+
+static void __paint_it(struct kmemleak_object *object, int color)
+{
+	object->min_count = color;
+	if (color == KMEMLEAK_BLACK)
+		object->flags |= OBJECT_NO_SCAN;
+}
+
+static void paint_it(struct kmemleak_object *object, int color)
 {
 	unsigned long flags;
+
+	spin_lock_irqsave(&object->lock, flags);
+	__paint_it(object, color);
+	spin_unlock_irqrestore(&object->lock, flags);
+}
+
+static void paint_ptr(unsigned long ptr, int color)
+{
 	struct kmemleak_object *object;
 
 	object = find_and_get_object(ptr, 0);
 	if (!object) {
-		kmemleak_warn("Graying unknown object at 0x%08lx\n", ptr);
+		kmemleak_warn("Trying to color unknown object "
+			      "at 0x%08lx as %s\n", ptr,
+			      (color == KMEMLEAK_GREY) ? "Grey" :
+			      (color == KMEMLEAK_BLACK) ? "Black" : "Unknown");
 		return;
 	}
-
-	spin_lock_irqsave(&object->lock, flags);
-	object->min_count = 0;
-	spin_unlock_irqrestore(&object->lock, flags);
+	paint_it(object, color);
 	put_object(object);
 }
 
 /*
+ * Make a object permanently as gray-colored so that it can no longer be
+ * reported as a leak. This is used in general to mark a false positive.
+ */
+static void make_gray_object(unsigned long ptr)
+{
+	paint_ptr(ptr, KMEMLEAK_GREY);
+}
+
+/*
  * Mark the object as black-colored so that it is ignored from scans and
  * reporting.
  */
 static void make_black_object(unsigned long ptr)
 {
-	unsigned long flags;
-	struct kmemleak_object *object;
-
-	object = find_and_get_object(ptr, 0);
-	if (!object) {
-		kmemleak_warn("Blacking unknown object at 0x%08lx\n", ptr);
-		return;
-	}
-
-	spin_lock_irqsave(&object->lock, flags);
-	object->min_count = -1;
-	spin_unlock_irqrestore(&object->lock, flags);
-	put_object(object);
+	paint_ptr(ptr, KMEMLEAK_BLACK);
 }
 
 /*
@@ -715,14 +785,15 @@ static void object_no_scan(unsigned long ptr)
  * Log an early kmemleak_* call to the early_log buffer. These calls will be
  * processed later once kmemleak is fully initialized.
  */
-static void log_early(int op_type, const void *ptr, size_t size,
-		      int min_count, unsigned long offset, size_t length)
+static void __init log_early(int op_type, const void *ptr, size_t size,
+			     int min_count, unsigned long offset, size_t length)
 {
 	unsigned long flags;
 	struct early_log *log;
 
 	if (crt_early_log >= ARRAY_SIZE(early_log)) {
-		pr_warning("Early log buffer exceeded\n");
+		pr_warning("Early log buffer exceeded, "
+			   "please increase DEBUG_KMEMLEAK_EARLY_LOG_SIZE\n");
 		kmemleak_disable();
 		return;
 	}
@@ -739,16 +810,45 @@ static void log_early(int op_type, const void *ptr, size_t size,
 	log->min_count = min_count;
 	log->offset = offset;
 	log->length = length;
+	if (op_type == KMEMLEAK_ALLOC)
+		log->trace_len = __save_stack_trace(log->trace);
 	crt_early_log++;
 	local_irq_restore(flags);
 }
 
 /*
+ * Log an early allocated block and populate the stack trace.
+ */
+static void early_alloc(struct early_log *log)
+{
+	struct kmemleak_object *object;
+	unsigned long flags;
+	int i;
+
+	if (!atomic_read(&kmemleak_enabled) || !log->ptr || IS_ERR(log->ptr))
+		return;
+
+	/*
+	 * RCU locking needed to ensure object is not freed via put_object().
+	 */
+	rcu_read_lock();
+	object = create_object((unsigned long)log->ptr, log->size,
+			       log->min_count, GFP_KERNEL);
+	spin_lock_irqsave(&object->lock, flags);
+	for (i = 0; i < log->trace_len; i++)
+		object->trace[i] = log->trace[i];
+	object->trace_len = log->trace_len;
+	spin_unlock_irqrestore(&object->lock, flags);
+	rcu_read_unlock();
+}
+
+/*
  * Memory allocation function callback. This function is called from the
  * kernel allocators when a new block is allocated (kmem_cache_alloc, kmalloc,
  * vmalloc etc.).
  */
-void kmemleak_alloc(const void *ptr, size_t size, int min_count, gfp_t gfp)
+void __ref kmemleak_alloc(const void *ptr, size_t size, int min_count,
+			  gfp_t gfp)
 {
 	pr_debug("%s(0x%p, %zu, %d)\n", __func__, ptr, size, min_count);
 
@@ -763,7 +863,7 @@ EXPORT_SYMBOL_GPL(kmemleak_alloc);
  * Memory freeing function callback. This function is called from the kernel
  * allocators when a block is freed (kmem_cache_free, kfree, vfree etc.).
  */
-void kmemleak_free(const void *ptr)
+void __ref kmemleak_free(const void *ptr)
 {
 	pr_debug("%s(0x%p)\n", __func__, ptr);
 
@@ -778,7 +878,7 @@ EXPORT_SYMBOL_GPL(kmemleak_free);
  * Partial memory freeing function callback. This function is usually called
  * from bootmem allocator when (part of) a memory block is freed.
  */
-void kmemleak_free_part(const void *ptr, size_t size)
+void __ref kmemleak_free_part(const void *ptr, size_t size)
 {
 	pr_debug("%s(0x%p)\n", __func__, ptr);
 
@@ -793,7 +893,7 @@ EXPORT_SYMBOL_GPL(kmemleak_free_part);
  * Mark an already allocated memory block as a false positive. This will cause
  * the block to no longer be reported as leak and always be scanned.
  */
-void kmemleak_not_leak(const void *ptr)
+void __ref kmemleak_not_leak(const void *ptr)
 {
 	pr_debug("%s(0x%p)\n", __func__, ptr);
 
@@ -809,7 +909,7 @@ EXPORT_SYMBOL(kmemleak_not_leak);
  * corresponding block is not a leak and does not contain any references to
  * other allocated memory blocks.
  */
-void kmemleak_ignore(const void *ptr)
+void __ref kmemleak_ignore(const void *ptr)
 {
 	pr_debug("%s(0x%p)\n", __func__, ptr);
 
@@ -823,8 +923,8 @@ EXPORT_SYMBOL(kmemleak_ignore);
 /*
  * Limit the range to be scanned in an allocated memory block.
  */
-void kmemleak_scan_area(const void *ptr, unsigned long offset, size_t length,
-			gfp_t gfp)
+void __ref kmemleak_scan_area(const void *ptr, unsigned long offset,
+			      size_t length, gfp_t gfp)
 {
 	pr_debug("%s(0x%p)\n", __func__, ptr);
 
@@ -838,7 +938,7 @@ EXPORT_SYMBOL(kmemleak_scan_area);
 /*
  * Inform kmemleak not to scan the given memory block.
  */
-void kmemleak_no_scan(const void *ptr)
+void __ref kmemleak_no_scan(const void *ptr)
 {
 	pr_debug("%s(0x%p)\n", __func__, ptr);
 
@@ -882,15 +982,22 @@ static void scan_block(void *_start, void *_end,
 	unsigned long *end = _end - (BYTES_PER_POINTER - 1);
 
 	for (ptr = start; ptr < end; ptr++) {
-		unsigned long flags;
-		unsigned long pointer = *ptr;
 		struct kmemleak_object *object;
+		unsigned long flags;
+		unsigned long pointer;
 
 		if (allow_resched)
 			cond_resched();
 		if (scan_should_stop())
 			break;
 
+		/* don't scan uninitialized memory */
+		if (!kmemcheck_is_obj_initialized((unsigned long)ptr,
+						  BYTES_PER_POINTER))
+			continue;
+
+		pointer = *ptr;
+
 		object = find_and_get_object(pointer, 1);
 		if (!object)
 			continue;
@@ -949,10 +1056,21 @@ static void scan_object(struct kmemleak_object *object)
 	if (!(object->flags & OBJECT_ALLOCATED))
 		/* already freed object */
 		goto out;
-	if (hlist_empty(&object->area_list))
-		scan_block((void *)object->pointer,
-			   (void *)(object->pointer + object->size), object, 0);
-	else
+	if (hlist_empty(&object->area_list)) {
+		void *start = (void *)object->pointer;
+		void *end = (void *)(object->pointer + object->size);
+
+		while (start < end && (object->flags & OBJECT_ALLOCATED) &&
+		       !(object->flags & OBJECT_NO_SCAN)) {
+			scan_block(start, min(start + MAX_SCAN_SIZE, end),
+				   object, 0);
+			start += MAX_SCAN_SIZE;
+
+			spin_unlock_irqrestore(&object->lock, flags);
+			cond_resched();
+			spin_lock_irqsave(&object->lock, flags);
+		}
+	} else
 		hlist_for_each_entry(area, elem, &object->area_list, node)
 			scan_block((void *)(object->pointer + area->offset),
 				   (void *)(object->pointer + area->offset
@@ -970,7 +1088,6 @@ static void kmemleak_scan(void)
 {
 	unsigned long flags;
 	struct kmemleak_object *object, *tmp;
-	struct task_struct *task;
 	int i;
 	int new_leaks = 0;
 	int gray_list_pass = 0;
@@ -1037,15 +1154,16 @@ static void kmemleak_scan(void)
 	}
 
 	/*
-	 * Scanning the task stacks may introduce false negatives and it is
-	 * not enabled by default.
+	 * Scanning the task stacks (may introduce false negatives).
 	 */
 	if (kmemleak_stack_scan) {
+		struct task_struct *p, *g;
+
 		read_lock(&tasklist_lock);
-		for_each_process(task)
-			scan_block(task_stack_page(task),
-				   task_stack_page(task) + THREAD_SIZE,
-				   NULL, 0);
+		do_each_thread(g, p) {
+			scan_block(task_stack_page(p), task_stack_page(p) +
+				   THREAD_SIZE, NULL, 0);
+		} while_each_thread(g, p);
 		read_unlock(&tasklist_lock);
 	}
 
@@ -1170,7 +1288,7 @@ static int kmemleak_scan_thread(void *arg)
  * Start the automatic memory scanning thread. This function must be called
  * with the scan_mutex held.
  */
-void start_scan_thread(void)
+static void start_scan_thread(void)
 {
 	if (scan_thread)
 		return;
@@ -1185,7 +1303,7 @@ void start_scan_thread(void)
  * Stop the automatic memory scanning thread. This function must be called
  * with the scan_mutex held.
  */
-void stop_scan_thread(void)
+static void stop_scan_thread(void)
 {
 	if (scan_thread) {
 		kthread_stop(scan_thread);
@@ -1294,6 +1412,49 @@ static int kmemleak_release(struct inode *inode, struct file *file)
 	return seq_release(inode, file);
 }
 
+static int dump_str_object_info(const char *str)
+{
+	unsigned long flags;
+	struct kmemleak_object *object;
+	unsigned long addr;
+
+	addr= simple_strtoul(str, NULL, 0);
+	object = find_and_get_object(addr, 0);
+	if (!object) {
+		pr_info("Unknown object at 0x%08lx\n", addr);
+		return -EINVAL;
+	}
+
+	spin_lock_irqsave(&object->lock, flags);
+	dump_object_info(object);
+	spin_unlock_irqrestore(&object->lock, flags);
+
+	put_object(object);
+	return 0;
+}
+
+/*
+ * We use grey instead of black to ensure we can do future scans on the same
+ * objects. If we did not do future scans these black objects could
+ * potentially contain references to newly allocated objects in the future and
+ * we'd end up with false positives.
+ */
+static void kmemleak_clear(void)
+{
+	struct kmemleak_object *object;
+	unsigned long flags;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(object, &object_list, object_list) {
+		spin_lock_irqsave(&object->lock, flags);
+		if ((object->flags & OBJECT_REPORTED) &&
+		    unreferenced_object(object))
+			__paint_it(object, KMEMLEAK_GREY);
+		spin_unlock_irqrestore(&object->lock, flags);
+	}
+	rcu_read_unlock();
+}
+
 /*
  * File write operation to configure kmemleak at run-time. The following
  * commands can be written to the /sys/kernel/debug/kmemleak file:
@@ -1305,6 +1466,9 @@ static int kmemleak_release(struct inode *inode, struct file *file)
  *   scan=...	- set the automatic memory scanning period in seconds (0 to
  *		  disable it)
  *   scan	- trigger a memory scan
+ *   clear	- mark all current reported unreferenced kmemleak objects as
+ *		  grey to ignore printing them
+ *   dump=...	- dump information about the object found at the given address
  */
 static ssize_t kmemleak_write(struct file *file, const char __user *user_buf,
 			      size_t size, loff_t *ppos)
@@ -1345,6 +1509,10 @@ static ssize_t kmemleak_write(struct file *file, const char __user *user_buf,
 		}
 	} else if (strncmp(buf, "scan", 4) == 0)
 		kmemleak_scan();
+	else if (strncmp(buf, "clear", 5) == 0)
+		kmemleak_clear();
+	else if (strncmp(buf, "dump=", 5) == 0)
+		ret = dump_str_object_info(buf + 5);
 	else
 		ret = -EINVAL;
 
@@ -1371,7 +1539,7 @@ static const struct file_operations kmemleak_fops = {
  * Perform the freeing of the kmemleak internal objects after waiting for any
  * current memory scan to complete.
  */
-static int kmemleak_cleanup_thread(void *arg)
+static void kmemleak_do_cleanup(struct work_struct *work)
 {
 	struct kmemleak_object *object;
 
@@ -1383,22 +1551,9 @@ static int kmemleak_cleanup_thread(void *arg)
 		delete_object_full(object->pointer);
 	rcu_read_unlock();
 	mutex_unlock(&scan_mutex);
-
-	return 0;
 }
 
-/*
- * Start the clean-up thread.
- */
-static void kmemleak_cleanup(void)
-{
-	struct task_struct *cleanup_thread;
-
-	cleanup_thread = kthread_run(kmemleak_cleanup_thread, NULL,
-				     "kmemleak-clean");
-	if (IS_ERR(cleanup_thread))
-		pr_warning("Failed to create the clean-up thread\n");
-}
+static DECLARE_WORK(cleanup_work, kmemleak_do_cleanup);
 
 /*
  * Disable kmemleak. No memory allocation/freeing will be traced once this
@@ -1416,7 +1571,7 @@ static void kmemleak_disable(void)
 
 	/* check whether it is too early for a kernel thread */
 	if (atomic_read(&kmemleak_initialized))
-		kmemleak_cleanup();
+		schedule_work(&cleanup_work);
 
 	pr_info("Kernel memory leak detector disabled\n");
 }
@@ -1469,8 +1624,7 @@ void __init kmemleak_init(void)
 
 		switch (log->op_type) {
 		case KMEMLEAK_ALLOC:
-			kmemleak_alloc(log->ptr, log->size, log->min_count,
-				       GFP_KERNEL);
+			early_alloc(log);
 			break;
 		case KMEMLEAK_FREE:
 			kmemleak_free(log->ptr);
@@ -1513,7 +1667,7 @@ static int __init kmemleak_late_init(void)
 		 * after setting kmemleak_initialized and we may end up with
 		 * two clean-up threads but serialized by scan_mutex.
 		 */
-		kmemleak_cleanup();
+		schedule_work(&cleanup_work);
 		return -ENOMEM;
 	}
 
diff --git a/mm/nommu.c b/mm/nommu.c
index 4bde489ec43..66e81e7e9fe 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -1352,6 +1352,7 @@ unsigned long do_mmap_pgoff(struct file *file,
 	}
 
 	vma->vm_region = region;
+	add_nommu_region(region);
 
 	/* set up the mapping */
 	if (file && vma->vm_flags & VM_SHARED)
@@ -1361,8 +1362,6 @@ unsigned long do_mmap_pgoff(struct file *file,
 	if (ret < 0)
 		goto error_put_region;
 
-	add_nommu_region(region);
-
 	/* okay... we have a mapping; now we have to register it */
 	result = vma->vm_start;
 
diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 81627ebcd31..25e7770309b 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -36,15 +36,6 @@
 #include <linux/pagevec.h>
 
 /*
- * The maximum number of pages to writeout in a single bdflush/kupdate
- * operation.  We do this so we don't hold I_SYNC against an inode for
- * enormous amounts of time, which would block a userspace task which has
- * been forced to throttle against that inode.  Also, the code reevaluates
- * the dirty each time it has written this many pages.
- */
-#define MAX_WRITEBACK_PAGES	1024
-
-/*
  * After a CPU has dirtied this many pages, balance_dirty_pages_ratelimited
  * will look to see if it needs to force writeback or throttling.
  */
@@ -117,8 +108,6 @@ EXPORT_SYMBOL(laptop_mode);
 /* End of sysctl-exported parameters */
 
 
-static void background_writeout(unsigned long _min_pages);
-
 /*
  * Scale the writeback cache size proportional to the relative writeout speeds.
  *
@@ -320,15 +309,13 @@ static void task_dirty_limit(struct task_struct *tsk, unsigned long *pdirty)
 /*
  *
  */
-static DEFINE_SPINLOCK(bdi_lock);
 static unsigned int bdi_min_ratio;
 
 int bdi_set_min_ratio(struct backing_dev_info *bdi, unsigned int min_ratio)
 {
 	int ret = 0;
-	unsigned long flags;
 
-	spin_lock_irqsave(&bdi_lock, flags);
+	spin_lock(&bdi_lock);
 	if (min_ratio > bdi->max_ratio) {
 		ret = -EINVAL;
 	} else {
@@ -340,27 +327,26 @@ int bdi_set_min_ratio(struct backing_dev_info *bdi, unsigned int min_ratio)
 			ret = -EINVAL;
 		}
 	}
-	spin_unlock_irqrestore(&bdi_lock, flags);
+	spin_unlock(&bdi_lock);
 
 	return ret;
 }
 
 int bdi_set_max_ratio(struct backing_dev_info *bdi, unsigned max_ratio)
 {
-	unsigned long flags;
 	int ret = 0;
 
 	if (max_ratio > 100)
 		return -EINVAL;
 
-	spin_lock_irqsave(&bdi_lock, flags);
+	spin_lock(&bdi_lock);
 	if (bdi->min_ratio > max_ratio) {
 		ret = -EINVAL;
 	} else {
 		bdi->max_ratio = max_ratio;
 		bdi->max_prop_frac = (PROP_FRAC_BASE * max_ratio) / 100;
 	}
-	spin_unlock_irqrestore(&bdi_lock, flags);
+	spin_unlock(&bdi_lock);
 
 	return ret;
 }
@@ -546,7 +532,7 @@ static void balance_dirty_pages(struct address_space *mapping)
 		 * up.
 		 */
 		if (bdi_nr_reclaimable > bdi_thresh) {
-			writeback_inodes(&wbc);
+			writeback_inodes_wbc(&wbc);
 			pages_written += write_chunk - wbc.nr_to_write;
 			get_dirty_limits(&background_thresh, &dirty_thresh,
 				       &bdi_thresh, bdi);
@@ -575,7 +561,7 @@ static void balance_dirty_pages(struct address_space *mapping)
 		if (pages_written >= write_chunk)
 			break;		/* We've done our duty */
 
-		congestion_wait(BLK_RW_ASYNC, HZ/10);
+		schedule_timeout(1);
 	}
 
 	if (bdi_nr_reclaimable + bdi_nr_writeback < bdi_thresh &&
@@ -594,10 +580,18 @@ static void balance_dirty_pages(struct address_space *mapping)
 	 * background_thresh, to keep the amount of dirty memory low.
 	 */
 	if ((laptop_mode && pages_written) ||
-			(!laptop_mode && (global_page_state(NR_FILE_DIRTY)
-					  + global_page_state(NR_UNSTABLE_NFS)
-					  > background_thresh)))
-		pdflush_operation(background_writeout, 0);
+	    (!laptop_mode && ((nr_writeback = global_page_state(NR_FILE_DIRTY)
+					  + global_page_state(NR_UNSTABLE_NFS))
+					  > background_thresh))) {
+		struct writeback_control wbc = {
+			.bdi		= bdi,
+			.sync_mode	= WB_SYNC_NONE,
+			.nr_to_write	= nr_writeback,
+		};
+
+
+		bdi_start_writeback(&wbc);
+	}
 }
 
 void set_page_dirty_balance(struct page *page, int page_mkwrite)
@@ -681,153 +675,35 @@ void throttle_vm_writeout(gfp_t gfp_mask)
         }
 }
 
-/*
- * writeback at least _min_pages, and keep writing until the amount of dirty
- * memory is less than the background threshold, or until we're all clean.
- */
-static void background_writeout(unsigned long _min_pages)
-{
-	long min_pages = _min_pages;
-	struct writeback_control wbc = {
-		.bdi		= NULL,
-		.sync_mode	= WB_SYNC_NONE,
-		.older_than_this = NULL,
-		.nr_to_write	= 0,
-		.nonblocking	= 1,
-		.range_cyclic	= 1,
-	};
-
-	for ( ; ; ) {
-		unsigned long background_thresh;
-		unsigned long dirty_thresh;
-
-		get_dirty_limits(&background_thresh, &dirty_thresh, NULL, NULL);
-		if (global_page_state(NR_FILE_DIRTY) +
-			global_page_state(NR_UNSTABLE_NFS) < background_thresh
-				&& min_pages <= 0)
-			break;
-		wbc.more_io = 0;
-		wbc.encountered_congestion = 0;
-		wbc.nr_to_write = MAX_WRITEBACK_PAGES;
-		wbc.pages_skipped = 0;
-		writeback_inodes(&wbc);
-		min_pages -= MAX_WRITEBACK_PAGES - wbc.nr_to_write;
-		if (wbc.nr_to_write > 0 || wbc.pages_skipped > 0) {
-			/* Wrote less than expected */
-			if (wbc.encountered_congestion || wbc.more_io)
-				congestion_wait(BLK_RW_ASYNC, HZ/10);
-			else
-				break;
-		}
-	}
-}
-
-/*
- * Start writeback of `nr_pages' pages.  If `nr_pages' is zero, write back
- * the whole world.  Returns 0 if a pdflush thread was dispatched.  Returns
- * -1 if all pdflush threads were busy.
- */
-int wakeup_pdflush(long nr_pages)
-{
-	if (nr_pages == 0)
-		nr_pages = global_page_state(NR_FILE_DIRTY) +
-				global_page_state(NR_UNSTABLE_NFS);
-	return pdflush_operation(background_writeout, nr_pages);
-}
-
-static void wb_timer_fn(unsigned long unused);
 static void laptop_timer_fn(unsigned long unused);
 
-static DEFINE_TIMER(wb_timer, wb_timer_fn, 0, 0);
 static DEFINE_TIMER(laptop_mode_wb_timer, laptop_timer_fn, 0, 0);
 
 /*
- * Periodic writeback of "old" data.
- *
- * Define "old": the first time one of an inode's pages is dirtied, we mark the
- * dirtying-time in the inode's address_space.  So this periodic writeback code
- * just walks the superblock inode list, writing back any inodes which are
- * older than a specific point in time.
- *
- * Try to run once per dirty_writeback_interval.  But if a writeback event
- * takes longer than a dirty_writeback_interval interval, then leave a
- * one-second gap.
- *
- * older_than_this takes precedence over nr_to_write.  So we'll only write back
- * all dirty pages if they are all attached to "old" mappings.
- */
-static void wb_kupdate(unsigned long arg)
-{
-	unsigned long oldest_jif;
-	unsigned long start_jif;
-	unsigned long next_jif;
-	long nr_to_write;
-	struct writeback_control wbc = {
-		.bdi		= NULL,
-		.sync_mode	= WB_SYNC_NONE,
-		.older_than_this = &oldest_jif,
-		.nr_to_write	= 0,
-		.nonblocking	= 1,
-		.for_kupdate	= 1,
-		.range_cyclic	= 1,
-	};
-
-	sync_supers();
-
-	oldest_jif = jiffies - msecs_to_jiffies(dirty_expire_interval * 10);
-	start_jif = jiffies;
-	next_jif = start_jif + msecs_to_jiffies(dirty_writeback_interval * 10);
-	nr_to_write = global_page_state(NR_FILE_DIRTY) +
-			global_page_state(NR_UNSTABLE_NFS) +
-			(inodes_stat.nr_inodes - inodes_stat.nr_unused);
-	while (nr_to_write > 0) {
-		wbc.more_io = 0;
-		wbc.encountered_congestion = 0;
-		wbc.nr_to_write = MAX_WRITEBACK_PAGES;
-		writeback_inodes(&wbc);
-		if (wbc.nr_to_write > 0) {
-			if (wbc.encountered_congestion || wbc.more_io)
-				congestion_wait(BLK_RW_ASYNC, HZ/10);
-			else
-				break;	/* All the old data is written */
-		}
-		nr_to_write -= MAX_WRITEBACK_PAGES - wbc.nr_to_write;
-	}
-	if (time_before(next_jif, jiffies + HZ))
-		next_jif = jiffies + HZ;
-	if (dirty_writeback_interval)
-		mod_timer(&wb_timer, next_jif);
-}
-
-/*
  * sysctl handler for /proc/sys/vm/dirty_writeback_centisecs
  */
 int dirty_writeback_centisecs_handler(ctl_table *table, int write,
 	struct file *file, void __user *buffer, size_t *length, loff_t *ppos)
 {
 	proc_dointvec(table, write, file, buffer, length, ppos);
-	if (dirty_writeback_interval)
-		mod_timer(&wb_timer, jiffies +
-			msecs_to_jiffies(dirty_writeback_interval * 10));
-	else
-		del_timer(&wb_timer);
 	return 0;
 }
 
-static void wb_timer_fn(unsigned long unused)
-{
-	if (pdflush_operation(wb_kupdate, 0) < 0)
-		mod_timer(&wb_timer, jiffies + HZ); /* delay 1 second */
-}
-
-static void laptop_flush(unsigned long unused)
+static void do_laptop_sync(struct work_struct *work)
 {
-	sys_sync();
+	wakeup_flusher_threads(0);
+	kfree(work);
 }
 
 static void laptop_timer_fn(unsigned long unused)
 {
-	pdflush_operation(laptop_flush, 0);
+	struct work_struct *work;
+
+	work = kmalloc(sizeof(*work), GFP_ATOMIC);
+	if (work) {
+		INIT_WORK(work, do_laptop_sync);
+		schedule_work(work);
+	}
 }
 
 /*
@@ -910,8 +786,6 @@ void __init page_writeback_init(void)
 {
 	int shift;
 
-	mod_timer(&wb_timer,
-		  jiffies + msecs_to_jiffies(dirty_writeback_interval * 10));
 	writeback_set_ratelimit();
 	register_cpu_notifier(&ratelimit_nb);
 
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 5cc986eb9f6..a0de15f4698 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -817,13 +817,15 @@ __rmqueue_fallback(struct zone *zone, int order, int start_migratetype)
 			 * agressive about taking ownership of free pages
 			 */
 			if (unlikely(current_order >= (pageblock_order >> 1)) ||
-					start_migratetype == MIGRATE_RECLAIMABLE) {
+					start_migratetype == MIGRATE_RECLAIMABLE ||
+					page_group_by_mobility_disabled) {
 				unsigned long pages;
 				pages = move_freepages_block(zone, page,
 								start_migratetype);
 
 				/* Claim the whole block if over half of it is free */
-				if (pages >= (1 << (pageblock_order-1)))
+				if (pages >= (1 << (pageblock_order-1)) ||
+						page_group_by_mobility_disabled)
 					set_pageblock_migratetype(page,
 								start_migratetype);
 
diff --git a/mm/pdflush.c b/mm/pdflush.c
deleted file mode 100644
index 235ac440c44..00000000000
--- a/mm/pdflush.c
+++ /dev/null
@@ -1,269 +0,0 @@
-/*
- * mm/pdflush.c - worker threads for writing back filesystem data
- *
- * Copyright (C) 2002, Linus Torvalds.
- *
- * 09Apr2002	Andrew Morton
- *		Initial version
- * 29Feb2004	kaos@sgi.com
- *		Move worker thread creation to kthread to avoid chewing
- *		up stack space with nested calls to kernel_thread.
- */
-
-#include <linux/sched.h>
-#include <linux/list.h>
-#include <linux/signal.h>
-#include <linux/spinlock.h>
-#include <linux/gfp.h>
-#include <linux/init.h>
-#include <linux/module.h>
-#include <linux/fs.h>		/* Needed by writeback.h	  */
-#include <linux/writeback.h>	/* Prototypes pdflush_operation() */
-#include <linux/kthread.h>
-#include <linux/cpuset.h>
-#include <linux/freezer.h>
-
-
-/*
- * Minimum and maximum number of pdflush instances
- */
-#define MIN_PDFLUSH_THREADS	2
-#define MAX_PDFLUSH_THREADS	8
-
-static void start_one_pdflush_thread(void);
-
-
-/*
- * The pdflush threads are worker threads for writing back dirty data.
- * Ideally, we'd like one thread per active disk spindle.  But the disk
- * topology is very hard to divine at this level.   Instead, we take
- * care in various places to prevent more than one pdflush thread from
- * performing writeback against a single filesystem.  pdflush threads
- * have the PF_FLUSHER flag set in current->flags to aid in this.
- */
-
-/*
- * All the pdflush threads.  Protected by pdflush_lock
- */
-static LIST_HEAD(pdflush_list);
-static DEFINE_SPINLOCK(pdflush_lock);
-
-/*
- * The count of currently-running pdflush threads.  Protected
- * by pdflush_lock.
- *
- * Readable by sysctl, but not writable.  Published to userspace at
- * /proc/sys/vm/nr_pdflush_threads.
- */
-int nr_pdflush_threads = 0;
-
-/*
- * The time at which the pdflush thread pool last went empty
- */
-static unsigned long last_empty_jifs;
-
-/*
- * The pdflush thread.
- *
- * Thread pool management algorithm:
- * 
- * - The minimum and maximum number of pdflush instances are bound
- *   by MIN_PDFLUSH_THREADS and MAX_PDFLUSH_THREADS.
- * 
- * - If there have been no idle pdflush instances for 1 second, create
- *   a new one.
- * 
- * - If the least-recently-went-to-sleep pdflush thread has been asleep
- *   for more than one second, terminate a thread.
- */
-
-/*
- * A structure for passing work to a pdflush thread.  Also for passing
- * state information between pdflush threads.  Protected by pdflush_lock.
- */
-struct pdflush_work {
-	struct task_struct *who;	/* The thread */
-	void (*fn)(unsigned long);	/* A callback function */
-	unsigned long arg0;		/* An argument to the callback */
-	struct list_head list;		/* On pdflush_list, when idle */
-	unsigned long when_i_went_to_sleep;
-};
-
-static int __pdflush(struct pdflush_work *my_work)
-{
-	current->flags |= PF_FLUSHER | PF_SWAPWRITE;
-	set_freezable();
-	my_work->fn = NULL;
-	my_work->who = current;
-	INIT_LIST_HEAD(&my_work->list);
-
-	spin_lock_irq(&pdflush_lock);
-	for ( ; ; ) {
-		struct pdflush_work *pdf;
-
-		set_current_state(TASK_INTERRUPTIBLE);
-		list_move(&my_work->list, &pdflush_list);
-		my_work->when_i_went_to_sleep = jiffies;
-		spin_unlock_irq(&pdflush_lock);
-		schedule();
-		try_to_freeze();
-		spin_lock_irq(&pdflush_lock);
-		if (!list_empty(&my_work->list)) {
-			/*
-			 * Someone woke us up, but without removing our control
-			 * structure from the global list.  swsusp will do this
-			 * in try_to_freeze()->refrigerator().  Handle it.
-			 */
-			my_work->fn = NULL;
-			continue;
-		}
-		if (my_work->fn == NULL) {
-			printk("pdflush: bogus wakeup\n");
-			continue;
-		}
-		spin_unlock_irq(&pdflush_lock);
-
-		(*my_work->fn)(my_work->arg0);
-
-		spin_lock_irq(&pdflush_lock);
-
-		/*
-		 * Thread creation: For how long have there been zero
-		 * available threads?
-		 *
-		 * To throttle creation, we reset last_empty_jifs.
-		 */
-		if (time_after(jiffies, last_empty_jifs + 1 * HZ)) {
-			if (list_empty(&pdflush_list)) {
-				if (nr_pdflush_threads < MAX_PDFLUSH_THREADS) {
-					last_empty_jifs = jiffies;
-					nr_pdflush_threads++;
-					spin_unlock_irq(&pdflush_lock);
-					start_one_pdflush_thread();
-					spin_lock_irq(&pdflush_lock);
-				}
-			}
-		}
-
-		my_work->fn = NULL;
-
-		/*
-		 * Thread destruction: For how long has the sleepiest
-		 * thread slept?
-		 */
-		if (list_empty(&pdflush_list))
-			continue;
-		if (nr_pdflush_threads <= MIN_PDFLUSH_THREADS)
-			continue;
-		pdf = list_entry(pdflush_list.prev, struct pdflush_work, list);
-		if (time_after(jiffies, pdf->when_i_went_to_sleep + 1 * HZ)) {
-			/* Limit exit rate */
-			pdf->when_i_went_to_sleep = jiffies;
-			break;					/* exeunt */
-		}
-	}
-	nr_pdflush_threads--;
-	spin_unlock_irq(&pdflush_lock);
-	return 0;
-}
-
-/*
- * Of course, my_work wants to be just a local in __pdflush().  It is
- * separated out in this manner to hopefully prevent the compiler from
- * performing unfortunate optimisations against the auto variables.  Because
- * these are visible to other tasks and CPUs.  (No problem has actually
- * been observed.  This is just paranoia).
- */
-static int pdflush(void *dummy)
-{
-	struct pdflush_work my_work;
-	cpumask_var_t cpus_allowed;
-
-	/*
-	 * Since the caller doesn't even check kthread_run() worked, let's not
-	 * freak out too much if this fails.
-	 */
-	if (!alloc_cpumask_var(&cpus_allowed, GFP_KERNEL)) {
-		printk(KERN_WARNING "pdflush failed to allocate cpumask\n");
-		return 0;
-	}
-
-	/*
-	 * pdflush can spend a lot of time doing encryption via dm-crypt.  We
-	 * don't want to do that at keventd's priority.
-	 */
-	set_user_nice(current, 0);
-
-	/*
-	 * Some configs put our parent kthread in a limited cpuset,
-	 * which kthread() overrides, forcing cpus_allowed == cpu_all_mask.
-	 * Our needs are more modest - cut back to our cpusets cpus_allowed.
-	 * This is needed as pdflush's are dynamically created and destroyed.
-	 * The boottime pdflush's are easily placed w/o these 2 lines.
-	 */
-	cpuset_cpus_allowed(current, cpus_allowed);
-	set_cpus_allowed_ptr(current, cpus_allowed);
-	free_cpumask_var(cpus_allowed);
-
-	return __pdflush(&my_work);
-}
-
-/*
- * Attempt to wake up a pdflush thread, and get it to do some work for you.
- * Returns zero if it indeed managed to find a worker thread, and passed your
- * payload to it.
- */
-int pdflush_operation(void (*fn)(unsigned long), unsigned long arg0)
-{
-	unsigned long flags;
-	int ret = 0;
-
-	BUG_ON(fn == NULL);	/* Hard to diagnose if it's deferred */
-
-	spin_lock_irqsave(&pdflush_lock, flags);
-	if (list_empty(&pdflush_list)) {
-		ret = -1;
-	} else {
-		struct pdflush_work *pdf;
-
-		pdf = list_entry(pdflush_list.next, struct pdflush_work, list);
-		list_del_init(&pdf->list);
-		if (list_empty(&pdflush_list))
-			last_empty_jifs = jiffies;
-		pdf->fn = fn;
-		pdf->arg0 = arg0;
-		wake_up_process(pdf->who);
-	}
-	spin_unlock_irqrestore(&pdflush_lock, flags);
-
-	return ret;
-}
-
-static void start_one_pdflush_thread(void)
-{
-	struct task_struct *k;
-
-	k = kthread_run(pdflush, NULL, "pdflush");
-	if (unlikely(IS_ERR(k))) {
-		spin_lock_irq(&pdflush_lock);
-		nr_pdflush_threads--;
-		spin_unlock_irq(&pdflush_lock);
-	}
-}
-
-static int __init pdflush_init(void)
-{
-	int i;
-
-	/*
-	 * Pre-set nr_pdflush_threads...  If we fail to create,
-	 * the count will be decremented.
-	 */
-	nr_pdflush_threads = MIN_PDFLUSH_THREADS;
-
-	for (i = 0; i < MIN_PDFLUSH_THREADS; i++)
-		start_one_pdflush_thread();
-	return 0;
-}
-
-module_init(pdflush_init);
diff --git a/mm/percpu.c b/mm/percpu.c
index 5fe37842e0e..3311c8919f3 100644
--- a/mm/percpu.c
+++ b/mm/percpu.c
@@ -197,7 +197,12 @@ static unsigned long pcpu_chunk_addr(struct pcpu_chunk *chunk,
 static bool pcpu_chunk_page_occupied(struct pcpu_chunk *chunk,
 				     int page_idx)
 {
-	return *pcpu_chunk_pagep(chunk, 0, page_idx) != NULL;
+	/*
+	 * Any possible cpu id can be used here, so there's no need to
+	 * worry about preemption or cpu hotplug.
+	 */
+	return *pcpu_chunk_pagep(chunk, raw_smp_processor_id(),
+				 page_idx) != NULL;
 }
 
 /* set the pointer to a chunk in a page struct */
@@ -297,6 +302,14 @@ static struct pcpu_chunk *pcpu_chunk_addr_search(void *addr)
 		return pcpu_first_chunk;
 	}
 
+	/*
+	 * The address is relative to unit0 which might be unused and
+	 * thus unmapped.  Offset the address to the unit space of the
+	 * current processor before looking it up in the vmalloc
+	 * space.  Note that any possible cpu id can be used here, so
+	 * there's no need to worry about preemption or cpu hotplug.
+	 */
+	addr += raw_smp_processor_id() * pcpu_unit_size;
 	return pcpu_get_page_chunk(vmalloc_to_page(addr));
 }
 
diff --git a/mm/shmem.c b/mm/shmem.c
index d713239ce2c..5a0b3d4055f 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -2446,7 +2446,7 @@ static const struct inode_operations shmem_inode_operations = {
 	.getxattr	= generic_getxattr,
 	.listxattr	= generic_listxattr,
 	.removexattr	= generic_removexattr,
-	.permission	= shmem_permission,
+	.check_acl	= shmem_check_acl,
 #endif
 
 };
@@ -2469,7 +2469,7 @@ static const struct inode_operations shmem_dir_inode_operations = {
 	.getxattr	= generic_getxattr,
 	.listxattr	= generic_listxattr,
 	.removexattr	= generic_removexattr,
-	.permission	= shmem_permission,
+	.check_acl	= shmem_check_acl,
 #endif
 };
 
@@ -2480,7 +2480,7 @@ static const struct inode_operations shmem_special_inode_operations = {
 	.getxattr	= generic_getxattr,
 	.listxattr	= generic_listxattr,
 	.removexattr	= generic_removexattr,
-	.permission	= shmem_permission,
+	.check_acl	= shmem_check_acl,
 #endif
 };
 
diff --git a/mm/shmem_acl.c b/mm/shmem_acl.c
index 606a8e757a4..df2c87fdae5 100644
--- a/mm/shmem_acl.c
+++ b/mm/shmem_acl.c
@@ -157,7 +157,7 @@ shmem_acl_init(struct inode *inode, struct inode *dir)
 /**
  * shmem_check_acl  -  check_acl() callback for generic_permission()
  */
-static int
+int
 shmem_check_acl(struct inode *inode, int mask)
 {
 	struct posix_acl *acl = shmem_get_acl(inode, ACL_TYPE_ACCESS);
@@ -169,12 +169,3 @@ shmem_check_acl(struct inode *inode, int mask)
 	}
 	return -EAGAIN;
 }
-
-/**
- * shmem_permission  -  permission() inode operation
- */
-int
-shmem_permission(struct inode *inode, int mask)
-{
-	return generic_permission(inode, mask, shmem_check_acl);
-}
diff --git a/mm/slub.c b/mm/slub.c
index b9f1491a58a..b6276753626 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -2594,8 +2594,6 @@ static inline int kmem_cache_close(struct kmem_cache *s)
  */
 void kmem_cache_destroy(struct kmem_cache *s)
 {
-	if (s->flags & SLAB_DESTROY_BY_RCU)
-		rcu_barrier();
 	down_write(&slub_lock);
 	s->refcount--;
 	if (!s->refcount) {
@@ -2606,6 +2604,8 @@ void kmem_cache_destroy(struct kmem_cache *s)
 				"still has objects.\n", s->name, __func__);
 			dump_stack();
 		}
+		if (s->flags & SLAB_DESTROY_BY_RCU)
+			rcu_barrier();
 		sysfs_slab_remove(s);
 	} else
 		up_write(&slub_lock);
diff --git a/mm/swap_state.c b/mm/swap_state.c
index 42cd38eba79..5ae6b8b78c8 100644
--- a/mm/swap_state.c
+++ b/mm/swap_state.c
@@ -34,6 +34,7 @@ static const struct address_space_operations swap_aops = {
 };
 
 static struct backing_dev_info swap_backing_dev_info = {
+	.name		= "swap",
 	.capabilities	= BDI_CAP_NO_ACCT_AND_WRITEBACK | BDI_CAP_SWAP_BACKED,
 	.unplug_io_fn	= swap_unplug_io_fn,
 };
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 94e86dd6954..ba8228e0a80 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1720,7 +1720,7 @@ static unsigned long do_try_to_free_pages(struct zonelist *zonelist,
 		 */
 		if (total_scanned > sc->swap_cluster_max +
 					sc->swap_cluster_max / 2) {
-			wakeup_pdflush(laptop_mode ? 0 : total_scanned);
+			wakeup_flusher_threads(laptop_mode ? 0 : total_scanned);
 			sc->may_writepage = 1;
 		}