This patch centralizes computing of max rx/tx qlen, because:
- RX_QLEN()/TX_QLEN() is called in hot path
- computing depends on device's usb speed, now we have ls/fs, hs, ss,
so more checks need to be involved
- in fact, max rx/tx qlen should not only depend on device USB
speed, but also depend on ethernet link speed, so we need to
consider that in future.
- if SG support is done, max tx qlen may need change too
Generally, hard_mtu and rx_urb_size are changed in bind(), reset()
and link_reset() callback, and change mtu network operation, this
patches introduces the API of usbnet_update_max_qlen(), and calls
it in above path.
Signed-off-by: Ming Lei <ming....@canonical.com>
---
drivers/net/usb/asix_devices.c | 3 +++
drivers/net/usb/ax88179_178a.c | 3 +++
drivers/net/usb/usbnet.c | 45 +++++++++++++++++++++++++++++++++-------
include/linux/usb/usbnet.h | 3 +++
4 files changed, 46 insertions(+), 8 deletions(-)
diff --git a/drivers/net/usb/asix_devices.c b/drivers/net/usb/asix_devices.c
index ad5d1e4..b96ad4f 100644
--- a/drivers/net/usb/asix_devices.c
+++ b/drivers/net/usb/asix_devices.c
@@ -778,6 +778,9 @@ static int ax88178_change_mtu(struct net_device *net, int
new_mtu)
dev->hard_mtu = net->mtu + net->hard_header_len;
ax88178_set_mfb(dev);
+ /* max qlen depend on hard_mtu and rx_urb_size */
+ usbnet_update_max_qlen(dev);
+
return 0;
}
diff --git a/drivers/net/usb/ax88179_178a.c b/drivers/net/usb/ax88179_178a.c
index 2bc87e3..5a468f3 100644
--- a/drivers/net/usb/ax88179_178a.c
+++ b/drivers/net/usb/ax88179_178a.c
@@ -688,6 +688,9 @@ static int ax88179_change_mtu(struct net_device *net, int
new_mtu)
2, 2, &tmp16);
}
+ /* max qlen depend on hard_mtu and rx_urb_size */
+ usbnet_update_max_qlen(dev);
+
return 0;
}
diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c
index 06ee82f..d74de07 100644
--- a/drivers/net/usb/usbnet.c
+++ b/drivers/net/usb/usbnet.c
@@ -59,15 +59,13 @@
* For high speed, each frame comfortably fits almost 36 max size
* Ethernet packets (so queues should be bigger).
*
- * REVISIT qlens should be members of 'struct usbnet'; the goal is to
- * let the USB host controller be busy for 5msec or more before an irq
- * is required, under load. Jumbograms change the equation.
+ * The goal is to let the USB host controller be busy for 5msec or
+ * more before an irq is required, under load. Jumbograms change
+ * the equation.
*/
-#define RX_MAX_QUEUE_MEMORY (60 * 1518)
-#define RX_QLEN(dev) (((dev)->udev->speed == USB_SPEED_HIGH) ? \
- (RX_MAX_QUEUE_MEMORY/(dev)->rx_urb_size) : 4)
-#define TX_QLEN(dev) (((dev)->udev->speed == USB_SPEED_HIGH) ? \
- (RX_MAX_QUEUE_MEMORY/(dev)->hard_mtu) : 4)
+#define MAX_QUEUE_MEMORY (60 * 1518)
+#define RX_QLEN(dev) ((dev)->rx_qlen)
+#define TX_QLEN(dev) ((dev)->tx_qlen)
// reawaken network queue this soon after stopping; else watchdog barks
#define TX_TIMEOUT_JIFFIES (5*HZ)
@@ -347,6 +345,22 @@ void usbnet_skb_return (struct usbnet *dev, struct sk_buff
*skb)
}
EXPORT_SYMBOL_GPL(usbnet_skb_return);
+/* must be called if hard_mtu or rx_urb_size changed */
+void usbnet_update_max_qlen(struct usbnet *dev)
+{
+ enum usb_device_speed speed = dev->udev->speed;
+
+ switch (speed) {
+ case USB_SPEED_HIGH:
+ dev->rx_qlen = MAX_QUEUE_MEMORY / dev->rx_urb_size;
+ dev->tx_qlen = MAX_QUEUE_MEMORY / dev->hard_mtu;
+ break;
+ default:
+ dev->rx_qlen = dev->tx_qlen = 4;
+ }
+}
+EXPORT_SYMBOL_GPL(usbnet_update_max_qlen);
+
/*-------------------------------------------------------------------------
*
@@ -375,6 +389,9 @@ int usbnet_change_mtu (struct net_device *net, int new_mtu)
usbnet_unlink_rx_urbs(dev);
}
+ /* max qlen depend on hard_mtu and rx_urb_size */
+ usbnet_update_max_qlen(dev);
+
return 0;
}
EXPORT_SYMBOL_GPL(usbnet_change_mtu);
@@ -843,6 +860,9 @@ int usbnet_open (struct net_device *net)
goto done;
}
+ /* hard_mtu or rx_urb_size may change in reset() */
+ usbnet_update_max_qlen(dev);
+
// insist peer be connected
if (info->check_connect && (retval = info->check_connect (dev)) < 0) {
netif_dbg(dev, ifup, dev->net, "can't open; %d\n", retval);
@@ -927,6 +947,9 @@ int usbnet_set_settings (struct net_device *net, struct
ethtool_cmd *cmd)
if (dev->driver_info->link_reset)
dev->driver_info->link_reset(dev);
+ /* hard_mtu or rx_urb_size may change in link_reset() */
+ usbnet_update_max_qlen(dev);
+
return retval;
}
@@ -1020,6 +1043,9 @@ static void __handle_link_change(struct usbnet *dev)
tasklet_schedule(&dev->bh);
}
+ /* hard_mtu or rx_urb_size may change during link change */
+ usbnet_update_max_qlen(dev);
+
clear_bit(EVENT_LINK_CHANGE, &dev->flags);
}
@@ -1599,6 +1625,9 @@ usbnet_probe (struct usb_interface *udev, const struct
usb_device_id *prod)
if ((dev->driver_info->flags & FLAG_WWAN) != 0)
SET_NETDEV_DEVTYPE(net, &wwan_type);
+ /* initialize max rx_qlen and tx_qlen */
+ usbnet_update_max_qlen(dev);
+
status = register_netdev (net);
if (status)
goto out4;
diff --git a/include/linux/usb/usbnet.h b/include/linux/usb/usbnet.h
index f18d641..8fbc008 100644
--- a/include/linux/usb/usbnet.h
+++ b/include/linux/usb/usbnet.h
@@ -34,6 +34,7 @@ struct usbnet {
struct mutex phy_mutex;
unsigned char suspend_count;
unsigned char pkt_cnt, pkt_err;
+ unsigned short rx_qlen, tx_qlen;
/* i/o info: pipes etc */
unsigned in, out;
@@ -253,4 +254,6 @@ extern void usbnet_link_change(struct usbnet *, bool, bool);
extern int usbnet_status_start(struct usbnet *dev, gfp_t mem_flags);
extern void usbnet_status_stop(struct usbnet *dev);
+extern void usbnet_update_max_qlen(struct usbnet *dev);
+
#endif /* __LINUX_USB_USBNET_H */
--
1.7.9.5
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