[PATCH v2 2/2] staging: usbip: replace the interrupt safe spinlocks with common ones.

Harvey Yang harvey.huawei.yang at gmail.com
Tue Jan 22 05:31:31 UTC 2013


On the client side, we have a virtual hcd driver, there actually no hardware interrupts, so we do not need worry about race conditions caused by irq with spinlock held. Turning off irq is not good for system performance after all. Just replace them with a non interrupt safe version.

Signed-off-by: Harvey Yang <harvey.huawei.yang at gmail.com>
---
 drivers/staging/usbip/vhci_hcd.c |   76 ++++++++++++++++----------------------
 drivers/staging/usbip/vhci_rx.c  |   10 ++---
 drivers/staging/usbip/vhci_tx.c  |   14 +++----
 3 files changed, 42 insertions(+), 58 deletions(-)

diff --git a/drivers/staging/usbip/vhci_hcd.c b/drivers/staging/usbip/vhci_hcd.c
index c3aa219..216648d 100644
--- a/drivers/staging/usbip/vhci_hcd.c
+++ b/drivers/staging/usbip/vhci_hcd.c
@@ -121,11 +121,9 @@ static void dump_port_status_diff(u32 prev_status, u32 new_status)
 
 void rh_port_connect(int rhport, enum usb_device_speed speed)
 {
-	unsigned long	flags;
-
 	usbip_dbg_vhci_rh("rh_port_connect %d\n", rhport);
 
-	spin_lock_irqsave(&the_controller->lock, flags);
+	spin_lock(&the_controller->lock);
 
 	the_controller->port_status[rhport] |= USB_PORT_STAT_CONNECTION
 		| (1 << USB_PORT_FEAT_C_CONNECTION);
@@ -141,24 +139,22 @@ void rh_port_connect(int rhport, enum usb_device_speed speed)
 		break;
 	}
 
-	spin_unlock_irqrestore(&the_controller->lock, flags);
+	spin_unlock(&the_controller->lock);
 
 	usb_hcd_poll_rh_status(vhci_to_hcd(the_controller));
 }
 
 static void rh_port_disconnect(int rhport)
 {
-	unsigned long flags;
-
 	usbip_dbg_vhci_rh("rh_port_disconnect %d\n", rhport);
 
-	spin_lock_irqsave(&the_controller->lock, flags);
+	spin_lock(&the_controller->lock);
 
 	the_controller->port_status[rhport] &= ~USB_PORT_STAT_CONNECTION;
 	the_controller->port_status[rhport] |=
 					(1 << USB_PORT_FEAT_C_CONNECTION);
 
-	spin_unlock_irqrestore(&the_controller->lock, flags);
+	spin_unlock(&the_controller->lock);
 	usb_hcd_poll_rh_status(vhci_to_hcd(the_controller));
 }
 
@@ -183,7 +179,6 @@ static void rh_port_disconnect(int rhport)
 static int vhci_hub_status(struct usb_hcd *hcd, char *buf)
 {
 	struct vhci_hcd	*vhci;
-	unsigned long	flags;
 	int		retval;
 	int		rhport;
 	int		changed = 0;
@@ -193,7 +188,7 @@ static int vhci_hub_status(struct usb_hcd *hcd, char *buf)
 
 	vhci = hcd_to_vhci(hcd);
 
-	spin_lock_irqsave(&vhci->lock, flags);
+	spin_lock(&vhci->lock);
 	if (!HCD_HW_ACCESSIBLE(hcd)) {
 		usbip_dbg_vhci_rh("hw accessible flag not on?\n");
 		goto done;
@@ -216,7 +211,7 @@ static int vhci_hub_status(struct usb_hcd *hcd, char *buf)
 		usb_hcd_resume_root_hub(hcd);
 
 done:
-	spin_unlock_irqrestore(&vhci->lock, flags);
+	spin_unlock(&vhci->lock);
 	return changed ? retval : 0;
 }
 
@@ -237,7 +232,6 @@ static int vhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
 {
 	struct vhci_hcd	*dum;
 	int             retval = 0;
-	unsigned long   flags;
 	int		rhport;
 
 	u32 prev_port_status[VHCI_NPORTS];
@@ -257,7 +251,7 @@ static int vhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
 
 	dum = hcd_to_vhci(hcd);
 
-	spin_lock_irqsave(&dum->lock, flags);
+	spin_lock(&dum->lock);
 
 	/* store old status and compare now and old later */
 	if (usbip_dbg_flag_vhci_rh) {
@@ -410,7 +404,7 @@ static int vhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
 	}
 	usbip_dbg_vhci_rh(" bye\n");
 
-	spin_unlock_irqrestore(&dum->lock, flags);
+	spin_unlock(&dum->lock);
 
 	return retval;
 }
@@ -433,7 +427,6 @@ static void vhci_tx_urb(struct urb *urb)
 {
 	struct vhci_device *vdev = get_vdev(urb->dev);
 	struct vhci_priv *priv;
-	unsigned long flag;
 
 	if (!vdev) {
 		pr_err("could not get virtual device");
@@ -442,11 +435,11 @@ static void vhci_tx_urb(struct urb *urb)
 
 	priv = kzalloc(sizeof(struct vhci_priv), GFP_ATOMIC);
 
-	spin_lock_irqsave(&vdev->priv_lock, flag);
+	spin_lock(&vdev->priv_lock);
 
 	if (!priv) {
 		dev_err(&urb->dev->dev, "malloc vhci_priv\n");
-		spin_unlock_irqrestore(&vdev->priv_lock, flag);
+		spin_unlock(&vdev->priv_lock);
 		usbip_event_add(&vdev->ud, VDEV_EVENT_ERROR_MALLOC);
 		return;
 	}
@@ -463,7 +456,7 @@ static void vhci_tx_urb(struct urb *urb)
 	list_add_tail(&priv->list, &vdev->priv_tx);
 
 	wake_up(&vdev->waitq_tx);
-	spin_unlock_irqrestore(&vdev->priv_lock, flag);
+	spin_unlock(&vdev->priv_lock);
 }
 
 static int vhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb,
@@ -471,7 +464,6 @@ static int vhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb,
 {
 	struct device *dev = &urb->dev->dev;
 	int ret = 0;
-	unsigned long flags;
 	struct vhci_device *vdev;
 
 	usbip_dbg_vhci_hc("enter, usb_hcd %p urb %p mem_flags %d\n",
@@ -480,11 +472,11 @@ static int vhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb,
 	/* patch to usb_sg_init() is in 2.5.60 */
 	BUG_ON(!urb->transfer_buffer && urb->transfer_buffer_length);
 
-	spin_lock_irqsave(&the_controller->lock, flags);
+	spin_lock(&the_controller->lock);
 
 	if (urb->status != -EINPROGRESS) {
 		dev_err(dev, "URB already unlinked!, status %d\n", urb->status);
-		spin_unlock_irqrestore(&the_controller->lock, flags);
+		spin_unlock(&the_controller->lock);
 		return urb->status;
 	}
 
@@ -496,7 +488,7 @@ static int vhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb,
 	    vdev->ud.status == VDEV_ST_ERROR) {
 		dev_err(dev, "enqueue for inactive port %d\n", vdev->rhport);
 		spin_unlock(&vdev->ud.lock);
-		spin_unlock_irqrestore(&the_controller->lock, flags);
+		spin_unlock(&the_controller->lock);
 		return -ENODEV;
 	}
 	spin_unlock(&vdev->ud.lock);
@@ -571,14 +563,14 @@ static int vhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb,
 
 out:
 	vhci_tx_urb(urb);
-	spin_unlock_irqrestore(&the_controller->lock, flags);
+	spin_unlock(&the_controller->lock);
 
 	return 0;
 
 no_need_xmit:
 	usb_hcd_unlink_urb_from_ep(hcd, urb);
 no_need_unlink:
-	spin_unlock_irqrestore(&the_controller->lock, flags);
+	spin_unlock(&the_controller->lock);
 	usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb, urb->status);
 	return ret;
 }
@@ -631,19 +623,18 @@ no_need_unlink:
  */
 static int vhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
 {
-	unsigned long flags;
 	struct vhci_priv *priv;
 	struct vhci_device *vdev;
 
 	pr_info("dequeue a urb %p\n", urb);
 
-	spin_lock_irqsave(&the_controller->lock, flags);
+	spin_lock(&the_controller->lock);
 
 	priv = urb->hcpriv;
 	if (!priv) {
 		/* URB was never linked! or will be soon given back by
 		 * vhci_rx. */
-		spin_unlock_irqrestore(&the_controller->lock, flags);
+		spin_unlock(&the_controller->lock);
 		return 0;
 	}
 
@@ -651,7 +642,7 @@ static int vhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
 		int ret = 0;
 		ret = usb_hcd_check_unlink_urb(hcd, urb, status);
 		if (ret) {
-			spin_unlock_irqrestore(&the_controller->lock, flags);
+			spin_unlock(&the_controller->lock);
 			return ret;
 		}
 	}
@@ -661,16 +652,14 @@ static int vhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
 
 	if (!vdev->ud.tcp_socket) {
 		/* tcp connection is closed */
-		unsigned long flags2;
-
-		spin_lock_irqsave(&vdev->priv_lock, flags2);
+		spin_lock(&vdev->priv_lock);
 
 		pr_info("device %p seems to be disconnected\n", vdev);
 		list_del(&priv->list);
 		kfree(priv);
 		urb->hcpriv = NULL;
 
-		spin_unlock_irqrestore(&vdev->priv_lock, flags2);
+		spin_unlock(&vdev->priv_lock);
 
 		/*
 		 * If tcp connection is alive, we have sent CMD_UNLINK.
@@ -681,24 +670,23 @@ static int vhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
 
 		usb_hcd_unlink_urb_from_ep(hcd, urb);
 
-		spin_unlock_irqrestore(&the_controller->lock, flags);
+		spin_unlock(&the_controller->lock);
 		usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb,
 				     urb->status);
-		spin_lock_irqsave(&the_controller->lock, flags);
+		spin_lock(&the_controller->lock);
 
 	} else {
 		/* tcp connection is alive */
-		unsigned long flags2;
 		struct vhci_unlink *unlink;
 
-		spin_lock_irqsave(&vdev->priv_lock, flags2);
+		spin_lock(&vdev->priv_lock);
 
 		/* setup CMD_UNLINK pdu */
 		unlink = kzalloc(sizeof(struct vhci_unlink), GFP_ATOMIC);
 		if (!unlink) {
 			pr_err("malloc vhci_unlink\n");
-			spin_unlock_irqrestore(&vdev->priv_lock, flags2);
-			spin_unlock_irqrestore(&the_controller->lock, flags);
+			spin_unlock(&vdev->priv_lock);
+			spin_unlock(&the_controller->lock);
 			usbip_event_add(&vdev->ud, VDEV_EVENT_ERROR_MALLOC);
 			return -ENOMEM;
 		}
@@ -716,10 +704,10 @@ static int vhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
 		list_add_tail(&unlink->list, &vdev->unlink_tx);
 		wake_up(&vdev->waitq_tx);
 
-		spin_unlock_irqrestore(&vdev->priv_lock, flags2);
+		spin_unlock(&vdev->priv_lock);
 	}
 
-	spin_unlock_irqrestore(&the_controller->lock, flags);
+	spin_unlock(&the_controller->lock);
 
 	usbip_dbg_vhci_hc("leave\n");
 	return 0;
@@ -957,9 +945,9 @@ static int vhci_bus_suspend(struct usb_hcd *hcd)
 
 	dev_dbg(&hcd->self.root_hub->dev, "%s\n", __func__);
 
-	spin_lock_irq(&vhci->lock);
+	spin_lock(&vhci->lock);
 	hcd->state = HC_STATE_SUSPENDED;
-	spin_unlock_irq(&vhci->lock);
+	spin_unlock(&vhci->lock);
 
 	return 0;
 }
@@ -971,13 +959,13 @@ static int vhci_bus_resume(struct usb_hcd *hcd)
 
 	dev_dbg(&hcd->self.root_hub->dev, "%s\n", __func__);
 
-	spin_lock_irq(&vhci->lock);
+	spin_lock(&vhci->lock);
 	if (!HCD_HW_ACCESSIBLE(hcd)) {
 		rc = -ESHUTDOWN;
 	} else {
 		hcd->state = HC_STATE_RUNNING;
 	}
-	spin_unlock_irq(&vhci->lock);
+	spin_unlock(&vhci->lock);
 
 	return rc;
 }
diff --git a/drivers/staging/usbip/vhci_rx.c b/drivers/staging/usbip/vhci_rx.c
index ba5f1c0..faf8e60 100644
--- a/drivers/staging/usbip/vhci_rx.c
+++ b/drivers/staging/usbip/vhci_rx.c
@@ -68,7 +68,6 @@ static void vhci_recv_ret_submit(struct vhci_device *vdev,
 {
 	struct usbip_device *ud = &vdev->ud;
 	struct urb *urb;
-	unsigned long flags;
 
 	spin_lock(&vdev->priv_lock);
 	urb = pickup_urb_and_free_priv(vdev, pdu->base.seqnum);
@@ -101,9 +100,9 @@ static void vhci_recv_ret_submit(struct vhci_device *vdev,
 
 	usbip_dbg_vhci_rx("now giveback urb %p\n", urb);
 
-	spin_lock_irqsave(&the_controller->lock, flags);
+	spin_lock(&the_controller->lock);
 	usb_hcd_unlink_urb_from_ep(vhci_to_hcd(the_controller), urb);
-	spin_unlock_irqrestore(&the_controller->lock, flags);
+	spin_unlock(&the_controller->lock);
 
 	usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb, urb->status);
 
@@ -141,7 +140,6 @@ static void vhci_recv_ret_unlink(struct vhci_device *vdev,
 {
 	struct vhci_unlink *unlink;
 	struct urb *urb;
-	unsigned long flags;
 
 	usbip_dump_header(pdu);
 
@@ -171,9 +169,9 @@ static void vhci_recv_ret_unlink(struct vhci_device *vdev,
 		urb->status = pdu->u.ret_unlink.status;
 		pr_info("urb->status %d\n", urb->status);
 
-		spin_lock_irqsave(&the_controller->lock, flags);
+		spin_lock(&the_controller->lock);
 		usb_hcd_unlink_urb_from_ep(vhci_to_hcd(the_controller), urb);
-		spin_unlock_irqrestore(&the_controller->lock, flags);
+		spin_unlock(&the_controller->lock);
 
 		usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb,
 				     urb->status);
diff --git a/drivers/staging/usbip/vhci_tx.c b/drivers/staging/usbip/vhci_tx.c
index b1f0dcd..409fd99 100644
--- a/drivers/staging/usbip/vhci_tx.c
+++ b/drivers/staging/usbip/vhci_tx.c
@@ -46,18 +46,17 @@ static void setup_cmd_submit_pdu(struct usbip_header *pdup,  struct urb *urb)
 
 static struct vhci_priv *dequeue_from_priv_tx(struct vhci_device *vdev)
 {
-	unsigned long flags;
 	struct vhci_priv *priv, *tmp;
 
-	spin_lock_irqsave(&vdev->priv_lock, flags);
+	spin_lock(&vdev->priv_lock);
 
 	list_for_each_entry_safe(priv, tmp, &vdev->priv_tx, list) {
 		list_move_tail(&priv->list, &vdev->priv_rx);
-		spin_unlock_irqrestore(&vdev->priv_lock, flags);
+		spin_unlock(&vdev->priv_lock);
 		return priv;
 	}
 
-	spin_unlock_irqrestore(&vdev->priv_lock, flags);
+	spin_unlock(&vdev->priv_lock);
 
 	return NULL;
 }
@@ -136,18 +135,17 @@ static int vhci_send_cmd_submit(struct vhci_device *vdev)
 
 static struct vhci_unlink *dequeue_from_unlink_tx(struct vhci_device *vdev)
 {
-	unsigned long flags;
 	struct vhci_unlink *unlink, *tmp;
 
-	spin_lock_irqsave(&vdev->priv_lock, flags);
+	spin_lock(&vdev->priv_lock);
 
 	list_for_each_entry_safe(unlink, tmp, &vdev->unlink_tx, list) {
 		list_move_tail(&unlink->list, &vdev->unlink_rx);
-		spin_unlock_irqrestore(&vdev->priv_lock, flags);
+		spin_unlock(&vdev->priv_lock);
 		return unlink;
 	}
 
-	spin_unlock_irqrestore(&vdev->priv_lock, flags);
+	spin_unlock(&vdev->priv_lock);
 
 	return NULL;
 }
-- 
1.7.1




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