UPSTREAM: usb: gadget: u_ether: remove interrupt throttling

According to Dave Miller "the networking stack has a
hard requirement that all SKBs which are transmitted
must have their completion signalled in a fininte
amount of time. This is because, until the SKB is
freed by the driver, it holds onto socket,
netfilter, and other subsystem resources."

In summary, this means that using TX IRQ throttling
for the networking gadgets is, at least, complex and
we should avoid it for the time being.

Change-Id: Ice4107af47309054e67f1ab22cc7c2c6a393263d
Cc: <stable@vger.kernel.org>
Reported-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Tested-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Suggested-by: David Miller <davem@davemloft.net>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: William Wu <william.wu@rock-chips.com>
(cherry picked from commit fd9afd3cbe)
This commit is contained in:
Felipe Balbi
2016-11-01 13:20:22 +02:00
committed by Tao Huang
parent c8da07269b
commit 524ec9aad4

View File

@@ -742,14 +742,6 @@ static netdev_tx_t eth_start_xmit(struct sk_buff *skb,
req->length = length;
/* throttle high/super speed IRQ rate back slightly */
if (gadget_is_dualspeed(dev->gadget))
req->no_interrupt = (((dev->gadget->speed == USB_SPEED_HIGH ||
dev->gadget->speed == USB_SPEED_SUPER)) &&
!list_empty(&dev->tx_reqs))
? ((atomic_read(&dev->tx_qlen) % dev->qmult) != 0)
: 0;
retval = usb_ep_queue(in, req, GFP_ATOMIC);
switch (retval) {
default: