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, 35 insertions, 26 deletions

diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 882875465301..1969c001b3f9 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -1599,14 +1599,20 @@ static void handle_port_status(struct xhci_hcd *xhci,
 	max_ports = HCS_MAX_PORTS(xhci->hcs_params1);
 	if ((port_id <= 0) || (port_id > max_ports)) {
 		xhci_warn(xhci, "Invalid port id %d\n", port_id);
-		bogus_port_status = true;
-		goto cleanup;
+		inc_deq(xhci, xhci->event_ring);
+		return;
 	}
 
 	/* Figure out which usb_hcd this port is attached to:
 	 * is it a USB 3.0 port or a USB 2.0/1.1 port?
 	 */
 	major_revision = xhci->port_array[port_id - 1];
+
+	/* Find the right roothub. */
+	hcd = xhci_to_hcd(xhci);
+	if ((major_revision == 0x03) != (hcd->speed == HCD_USB3))
+		hcd = xhci->shared_hcd;
+
 	if (major_revision == 0) {
 		xhci_warn(xhci, "Event for port %u not in "
 				"Extended Capabilities, ignoring.\n",
@@ -1629,10 +1635,6 @@ static void handle_port_status(struct xhci_hcd *xhci,
 	 * into the index into the ports on the correct split roothub, and the
 	 * correct bus_state structure.
 	 */
-	/* Find the right roothub. */
-	hcd = xhci_to_hcd(xhci);
-	if ((major_revision == 0x03) != (hcd->speed == HCD_USB3))
-		hcd = xhci->shared_hcd;
 	bus_state = &xhci->bus_state[hcd_index(hcd)];
 	if (hcd->speed == HCD_USB3)
 		port_array = xhci->usb3_ports;
@@ -2027,8 +2029,8 @@ static int process_ctrl_td(struct xhci_hcd *xhci, struct xhci_td *td,
 		if (event_trb != ep_ring->dequeue &&
 				event_trb != td->last_trb)
 			td->urb->actual_length =
-				td->urb->transfer_buffer_length
-				- TRB_LEN(le32_to_cpu(event->transfer_len));
+				td->urb->transfer_buffer_length -
+				EVENT_TRB_LEN(le32_to_cpu(event->transfer_len));
 		else
 			td->urb->actual_length = 0;
 
@@ -2060,7 +2062,7 @@ static int process_ctrl_td(struct xhci_hcd *xhci, struct xhci_td *td,
 		/* Maybe the event was for the data stage? */
 			td->urb->actual_length =
 				td->urb->transfer_buffer_length -
-				TRB_LEN(le32_to_cpu(event->transfer_len));
+				EVENT_TRB_LEN(le32_to_cpu(event->transfer_len));
 			xhci_dbg(xhci, "Waiting for status "
 					"stage event\n");
 			return 0;
@@ -2096,7 +2098,7 @@ static int process_isoc_td(struct xhci_hcd *xhci, struct xhci_td *td,
 	/* handle completion code */
 	switch (trb_comp_code) {
 	case COMP_SUCCESS:
-		if (TRB_LEN(le32_to_cpu(event->transfer_len)) == 0) {
+		if (EVENT_TRB_LEN(le32_to_cpu(event->transfer_len)) == 0) {
 			frame->status = 0;
 			break;
 		}
@@ -2141,7 +2143,7 @@ static int process_isoc_td(struct xhci_hcd *xhci, struct xhci_td *td,
 				len += TRB_LEN(le32_to_cpu(cur_trb->generic.field[2]));
 		}
 		len += TRB_LEN(le32_to_cpu(cur_trb->generic.field[2])) -
-			TRB_LEN(le32_to_cpu(event->transfer_len));
+			EVENT_TRB_LEN(le32_to_cpu(event->transfer_len));
 
 		if (trb_comp_code != COMP_STOP_INVAL) {
 			frame->actual_length = len;
@@ -2199,7 +2201,7 @@ static int process_bulk_intr_td(struct xhci_hcd *xhci, struct xhci_td *td,
 	case COMP_SUCCESS:
 		/* Double check that the HW transferred everything. */
 		if (event_trb != td->last_trb ||
-				TRB_LEN(le32_to_cpu(event->transfer_len)) != 0) {
+		    EVENT_TRB_LEN(le32_to_cpu(event->transfer_len)) != 0) {
 			xhci_warn(xhci, "WARN Successful completion "
 					"on short TX\n");
 			if (td->urb->transfer_flags & URB_SHORT_NOT_OK)
@@ -2227,18 +2229,18 @@ static int process_bulk_intr_td(struct xhci_hcd *xhci, struct xhci_td *td,
 				"%d bytes untransferred\n",
 				td->urb->ep->desc.bEndpointAddress,
 				td->urb->transfer_buffer_length,
-				TRB_LEN(le32_to_cpu(event->transfer_len)));
+				EVENT_TRB_LEN(le32_to_cpu(event->transfer_len)));
 	/* Fast path - was this the last TRB in the TD for this URB? */
 	if (event_trb == td->last_trb) {
-		if (TRB_LEN(le32_to_cpu(event->transfer_len)) != 0) {
+		if (EVENT_TRB_LEN(le32_to_cpu(event->transfer_len)) != 0) {
 			td->urb->actual_length =
 				td->urb->transfer_buffer_length -
-				TRB_LEN(le32_to_cpu(event->transfer_len));
+				EVENT_TRB_LEN(le32_to_cpu(event->transfer_len));
 			if (td->urb->transfer_buffer_length <
 					td->urb->actual_length) {
 				xhci_warn(xhci, "HC gave bad length "
 						"of %d bytes left\n",
-					  TRB_LEN(le32_to_cpu(event->transfer_len)));
+					  EVENT_TRB_LEN(le32_to_cpu(event->transfer_len)));
 				td->urb->actual_length = 0;
 				if (td->urb->transfer_flags & URB_SHORT_NOT_OK)
 					*status = -EREMOTEIO;
@@ -2280,7 +2282,7 @@ static int process_bulk_intr_td(struct xhci_hcd *xhci, struct xhci_td *td,
 		if (trb_comp_code != COMP_STOP_INVAL)
 			td->urb->actual_length +=
 				TRB_LEN(le32_to_cpu(cur_trb->generic.field[2])) -
-				TRB_LEN(le32_to_cpu(event->transfer_len));
+				EVENT_TRB_LEN(le32_to_cpu(event->transfer_len));
 	}
 
 	return finish_td(xhci, td, event_trb, event, ep, status, false);
@@ -2368,7 +2370,7 @@ static int handle_tx_event(struct xhci_hcd *xhci,
 	 * transfer type
 	 */
 	case COMP_SUCCESS:
-		if (TRB_LEN(le32_to_cpu(event->transfer_len)) == 0)
+		if (EVENT_TRB_LEN(le32_to_cpu(event->transfer_len)) == 0)
 			break;
 		if (xhci->quirks & XHCI_TRUST_TX_LENGTH)
 			trb_comp_code = COMP_SHORT_TX;
@@ -2461,14 +2463,21 @@ static int handle_tx_event(struct xhci_hcd *xhci,
 		 * TD list.
 		 */
 		if (list_empty(&ep_ring->td_list)) {
-			xhci_warn(xhci, "WARN Event TRB for slot %d ep %d "
-					"with no TDs queued?\n",
-				  TRB_TO_SLOT_ID(le32_to_cpu(event->flags)),
-				  ep_index);
-			xhci_dbg(xhci, "Event TRB with TRB type ID %u\n",
-				 (le32_to_cpu(event->flags) &
-				  TRB_TYPE_BITMASK)>>10);
-			xhci_print_trb_offsets(xhci, (union xhci_trb *) event);
+			/*
+			 * A stopped endpoint may generate an extra completion
+			 * event if the device was suspended.  Don't print
+			 * warnings.
+			 */
+			if (!(trb_comp_code == COMP_STOP ||
+						trb_comp_code == COMP_STOP_INVAL)) {
+				xhci_warn(xhci, "WARN Event TRB for slot %d ep %d with no TDs queued?\n",
+						TRB_TO_SLOT_ID(le32_to_cpu(event->flags)),
+						ep_index);
+				xhci_dbg(xhci, "Event TRB with TRB type ID %u\n",
+						(le32_to_cpu(event->flags) &
+						 TRB_TYPE_BITMASK)>>10);
+				xhci_print_trb_offsets(xhci, (union xhci_trb *) event);
+			}
 			if (ep->skip) {
 				ep->skip = false;
 				xhci_dbg(xhci, "td_list is empty while skip "