Merge tag 'for_linus-20110831' of git://github.com/tytso/ext4

* tag 'for_linus-20110831' of git://github.com/tytso/ext4:
  ext4: remove i_mutex lock in ext4_evict_inode to fix lockdep complaining

3 files changed, 18 insertions, 4 deletions

diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index e717dfd2f2b4..b7d7bd0f066e 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -175,6 +175,7 @@ struct mpage_da_data {
  */
 #define EXT4_IO_END_UNWRITTEN   0x0001
 #define EXT4_IO_END_ERROR       0x0002
+#define EXT4_IO_END_QUEUED      0x0004
 
 struct ext4_io_page {
         struct page     *p_page;
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index c4da98a959ae..18d2558b7624 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -121,9 +121,6 @@ void ext4_evict_inode(struct inode *inode)
 
         trace_ext4_evict_inode(inode);
 
-        mutex_lock(&inode->i_mutex);
-        ext4_flush_completed_IO(inode);
-        mutex_unlock(&inode->i_mutex);
         ext4_ioend_wait(inode);
 
         if (inode->i_nlink) {
diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c
index 78839af7ce29..92f38ee13f8a 100644
--- a/fs/ext4/page-io.c
+++ b/fs/ext4/page-io.c
@@ -142,7 +142,23 @@ static void ext4_end_io_work(struct work_struct *work)
         unsigned long           flags;
         int                     ret;
 
-        mutex_lock(&inode->i_mutex);
+        if (!mutex_trylock(&inode->i_mutex)) {
+                /*
+                 * Requeue the work instead of waiting so that the work
+                 * items queued after this can be processed.
+                 */
+                queue_work(EXT4_SB(inode->i_sb)->dio_unwritten_wq, &io->work);
+                /*
+                 * To prevent the ext4-dio-unwritten thread from keeping
+                 * requeueing end_io requests and occupying cpu for too long,
+                 * yield the cpu if it sees an end_io request that has already
+                 * been requeued.
+                 */
+                if (io->flag & EXT4_IO_END_QUEUED)
+                        yield();
+                io->flag |= EXT4_IO_END_QUEUED;
+                return;
+        }
         ret = ext4_end_io_nolock(io);
         if (ret < 0) {
                 mutex_unlock(&inode->i_mutex);