Btrfs: wake up the tasks that wait for the io earlier

The tasks that wait for the IO_DONE flag just care about the io of the dirty
pages, so it is better to wake up them immediately after all the pages are
written, not the whole process of the io completes.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>

diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c
index 73de19c37f5aac5a366c655366861204fcc8eb47..a75eaa286b8a91bdad4e26de0ed02b08df62e3b8 100644 (file)
--- a/fs/btrfs/ordered-data.c
+++ b/fs/btrfs/ordered-data.c
@@ -349,10 +349,13 @@ int btrfs_dec_test_first_ordered_pending(struct inode *inode,
        if (!uptodate)
                set_bit(BTRFS_ORDERED_IOERR, &entry->flags);
 
-       if (entry->bytes_left == 0)
+       if (entry->bytes_left == 0) {
                ret = test_and_set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags);
-       else
+               if (waitqueue_active(&entry->wait))
+                       wake_up(&entry->wait);
+       } else {
                ret = 1;
+       }
 out:
        if (!ret && cached && entry) {
                *cached = entry;
@@ -410,10 +413,13 @@ have_entry:
        if (!uptodate)
                set_bit(BTRFS_ORDERED_IOERR, &entry->flags);
 
-       if (entry->bytes_left == 0)
+       if (entry->bytes_left == 0) {
                ret = test_and_set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags);
-       else
+               if (waitqueue_active(&entry->wait))
+                       wake_up(&entry->wait);
+       } else {
                ret = 1;
+       }
 out:
        if (!ret && cached && entry) {
                *cached = entry;