Merge branch 'drm-nouveau-next' of git://git.freedesktop.org/git/nouveau/linux-2.6 into drm-next

* 'drm-nouveau-next' of git://git.freedesktop.org/git/nouveau/linux-2.6: (353 commits)
  drm/nouveau: remove allocations from gart populate() hook
  drm/nvc0/fb: slightly improve PMFB intr handling, move out of nvc0_graph.c
  drm/nvc0/fifo: avoid touching missing subfifos
  drm/nvd9/disp: bail out of mode_set_base if no fb bound to crtc
  drm/nvd9/disp: stub some more api hooks so we don't oops on resume
  drm/nouveau: fix printk typo in ioremap failure path
  drm/nvc0/pm: minor clock readback fixes
  drm/nv40/pm: execute memory reset script from vbios
  drm/nv50/gr: refactor initialisation
  drm/nouveau: if requested, try harder at disabling sysmem pushbufs
  drm/nv50/gr: enable ctxprog xfer only when we need it to save power
  drm/nouveau/dp: add support for displayport table 0x30
  drm/nouveau/dp: return master dp table pointer too when looking up encoder
  drm/nouveau/bios: simplify U/d table hash matching func to just match
  drm/nouveau/dp: preserve non-pattern bits in DP_TRAINING_PATTERN_SET
  drm/nvc0/gr: remove MODULE_FIRMWARE() lines
  drm/nouveau/dp: use alternate lane mask for nvaf
  drm/nouveau/dp: link rate scripts are selected with a comparison table
  drm/nv40/pm: write nv40-specific reclocking routines
  drm/nv40/pm: parse geometric delta clock from vbios
  ...

1 files changed, 17 insertions, 1 deletions

diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c
index 78839af7ce2..92f38ee13f8 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);