diff options
| -rw-r--r-- | include/linux/wait.h | 2 | ||||
| -rw-r--r-- | kernel/sched/wait.c | 7 | ||||
| -rw-r--r-- | mm/filemap.c | 22 |
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- |