Merge branch 'writeback-workqueue' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq into for-3.10/core

Tejun writes:

-----

This is the pull request for the earlier patchset[1] with the same
name.  It's only three patches (the first one was committed to
workqueue tree) but the merge strategy is a bit involved due to the
dependencies.

* Because the conversion needs features from wq/for-3.10,
  block/for-3.10/core is based on rc3, and wq/for-3.10 has conflicts
  with rc3, I pulled mainline (rc5) into wq/for-3.10 to prevent those
  workqueue conflicts from flaring up in block tree.

* Resolving the issue that Jan and Dave raised about debugging
  requires arch-wide changes.  The patchset is being worked on[2] but
  it'll have to go through -mm after these changes show up in -next,
  and not included in this pull request.

The three commits are located in the following git branch.

  git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq.git writeback-workqueue

Pulling it into block/for-3.10/core produces a conflict in
drivers/md/raid5.c between the following two commits.

  e3620a3ad5 ("MD RAID5: Avoid accessing gendisk or queue structs when not available")
  2f6db2a707 ("raid5: use bio_reset()")

The conflict is trivial - one removes an "if ()" conditional while the
other removes "rbi->bi_next = NULL" right above it.  We just need to
remove both.  The merged branch is available at

  git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq.git block-test-merge

so that you can use it for verification.  The test merge commit has
proper merge description.

While these changes are a bit of pain to route, they make code simpler
and even have, while minute, measureable performance gain[3] even on a
workload which isn't particularly favorable to showing the benefits of
this conversion.

----

Fixed up the conflict.

Conflicts:
	drivers/md/raid5.c

Signed-off-by: Jens Axboe <axboe@kernel.dk>

1 files changed, 7 insertions, 6 deletions

diff --git a/drivers/usb/serial/io_ti.c b/drivers/usb/serial/io_ti.c
index c23776679f7..7777172206d 100644
--- a/drivers/usb/serial/io_ti.c
+++ b/drivers/usb/serial/io_ti.c
@@ -87,9 +87,6 @@ struct edgeport_port {
 	int close_pending;
 	int lsr_event;
 	struct async_icount	icount;
-	wait_queue_head_t	delta_msr_wait;	/* for handling sleeping while
-						   waiting for msr change to
-						   happen */
 	struct edgeport_serial	*edge_serial;
 	struct usb_serial_port	*port;
 	__u8 bUartMode;		/* Port type, 0: RS232, etc. */
@@ -1459,7 +1456,7 @@ static void handle_new_msr(struct edgeport_port *edge_port, __u8 msr)
 			icount->dcd++;
 		if (msr & EDGEPORT_MSR_DELTA_RI)
 			icount->rng++;
-		wake_up_interruptible(&edge_port->delta_msr_wait);
+		wake_up_interruptible(&edge_port->port->delta_msr_wait);
 	}
 
 	/* Save the new modem status */
@@ -1754,7 +1751,6 @@ static int edge_open(struct tty_struct *tty, struct usb_serial_port *port)
 	dev = port->serial->dev;
 
 	memset(&(edge_port->icount), 0x00, sizeof(edge_port->icount));
-	init_waitqueue_head(&edge_port->delta_msr_wait);
 
 	/* turn off loopback */
 	status = ti_do_config(edge_port, UMPC_SET_CLR_LOOPBACK, 0);
@@ -2434,10 +2430,14 @@ static int edge_ioctl(struct tty_struct *tty,
 		dev_dbg(&port->dev, "%s - TIOCMIWAIT\n", __func__);
 		cprev = edge_port->icount;
 		while (1) {
-			interruptible_sleep_on(&edge_port->delta_msr_wait);
+			interruptible_sleep_on(&port->delta_msr_wait);
 			/* see if a signal did it */
 			if (signal_pending(current))
 				return -ERESTARTSYS;
+
+			if (port->serial->disconnected)
+				return -EIO;
+
 			cnow = edge_port->icount;
 			if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
 			    cnow.dcd == cprev.dcd && cnow.cts == cprev.cts)
@@ -2649,6 +2649,7 @@ static struct usb_serial_driver edgeport_2port_device = {
 	.set_termios		= edge_set_termios,
 	.tiocmget		= edge_tiocmget,
 	.tiocmset		= edge_tiocmset,
+	.get_icount		= edge_get_icount,
 	.write			= edge_write,
 	.write_room		= edge_write_room,
 	.chars_in_buffer	= edge_chars_in_buffer,