3 files changed, 30 insertions, 1 deletions

diff --git a/include/linux/wait.h b/include/linux/wait.h
index 78401ef02d29..87c4641023fb 100644
--- a/include/linux/wait.h
+++ b/include/linux/wait.h
@@ -185,6 +185,8 @@ __remove_wait_queue(struct wait_queue_head *wq_head, struct wait_queue_entry *wq
 
 void __wake_up(struct wait_queue_head *wq_head, unsigned int mode, int nr, void *key);
 void __wake_up_locked_key(struct wait_queue_head *wq_head, unsigned int mode, void *key);
+void __wake_up_locked_key_bookmark(struct wait_queue_head *wq_head,
+                unsigned int mode, void *key, wait_queue_entry_t *bookmark);
 void __wake_up_sync_key(struct wait_queue_head *wq_head, unsigned int mode, int nr, void *key);
 void __wake_up_locked(struct wait_queue_head *wq_head, unsigned int mode, int nr);
 void __wake_up_sync(struct wait_queue_head *wq_head, unsigned int mode, int nr);
diff --git a/kernel/sched/wait.c b/kernel/sched/wait.c
index 70701ef50465..98feab7933c7 100644
--- a/kernel/sched/wait.c
+++ b/kernel/sched/wait.c
@@ -165,6 +165,13 @@ void __wake_up_locked_key(struct wait_queue_head *wq_head, unsigned int mode, vo
 }
 EXPORT_SYMBOL_GPL(__wake_up_locked_key);
 
+void __wake_up_locked_key_bookmark(struct wait_queue_head *wq_head,
+                unsigned int mode, void *key, wait_queue_entry_t *bookmark)
+{
+        __wake_up_common(wq_head, mode, 1, 0, key, bookmark);
+}
+EXPORT_SYMBOL_GPL(__wake_up_locked_key_bookmark);
+
 /**
  * __wake_up_sync_key - wake up threads blocked on a waitqueue.
  * @wq_head: the waitqueue
diff --git a/mm/filemap.c b/mm/filemap.c
index 9d21afd692b9..8c88e186a773 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -909,13 +909,33 @@ static void wake_up_page_bit(struct page *page, int bit_nr)
         wait_queue_head_t *q = page_waitqueue(page);
         struct wait_page_key key;
         unsigned long flags;
+        wait_queue_entry_t bookmark;
 
         key.page = page;
         key.bit_nr = bit_nr;
         key.page_match = 0;
 
+        bookmark.flags = 0;
+        bookmark.private = NULL;
+        bookmark.func = NULL;
+        INIT_LIST_HEAD(&bookmark.entry);
+
         spin_lock_irqsave(&q->lock, flags);
-        __wake_up_locked_key(q, TASK_NORMAL, &key);
+        __wake_up_locked_key_bookmark(q, TASK_NORMAL, &key, &bookmark);
+
+        while (bookmark.flags & WQ_FLAG_BOOKMARK) {
+                /*
+                 * Take a breather from holding the lock,
+                 * allow pages that finish wake up asynchronously
+                 * to acquire the lock and remove themselves
+                 * from wait queue
+                 */
+                spin_unlock_irqrestore(&q->lock, flags);
+                cpu_relax();
+                spin_lock_irqsave(&q->lock, flags);
+                __wake_up_locked_key_bookmark(q, TASK_NORMAL, &key, &bookmark);
+        }
+
         /*
          * It is possible for other pages to have collided on the waitqueue
          * hash, so in that case check for a page match. That prevents a long-