@@ -189,7 +189,7 @@ struct sk_buff *asix_tx_fixup(struct usbnet *dev, struct sk_buff *skb,
skb_put(skb, sizeof(padbytes));
}
- usbnet_set_skb_tx_stats(skb, 1);
+ usbnet_set_skb_tx_stats(skb, 1, 0);
return skb;
}
@@ -1177,13 +1177,12 @@ cdc_ncm_fill_tx_frame(struct usbnet *dev, struct sk_buff *skb, __le32 sign)
ctx->tx_overhead += skb_out->len - ctx->tx_curr_frame_payload;
ctx->tx_ntbs++;
- /* usbnet has already counted all the framing overhead.
+ /* usbnet will count all the framing overhead by default.
* Adjust the stats so that the tx_bytes counter show real
* payload data instead.
*/
- dev->net->stats.tx_bytes -= skb_out->len - ctx->tx_curr_frame_payload;
-
- usbnet_set_skb_tx_stats(skb_out, n);
+ usbnet_set_skb_tx_stats(skb_out, n,
+ ctx->tx_curr_frame_payload - skb_out->len);
return skb_out;
@@ -144,7 +144,7 @@ static struct sk_buff *sr_tx_fixup(struct usbnet *dev, struct sk_buff *skb,
skb_put(skb, sizeof(padbytes));
}
- usbnet_set_skb_tx_stats(skb, 1);
+ usbnet_set_skb_tx_stats(skb, 1, 0);
return skb;
}
@@ -1322,9 +1322,19 @@ netdev_tx_t usbnet_start_xmit (struct sk_buff *skb,
} else
urb->transfer_flags |= URB_ZERO_PACKET;
}
- entry->length = urb->transfer_buffer_length = length;
- if (!(info->flags & FLAG_MULTI_PACKET))
- usbnet_set_skb_tx_stats(skb, 1);
+ urb->transfer_buffer_length = length;
+
+ if (info->flags & FLAG_MULTI_PACKET) {
+ /* Driver has set number of packets and a length delta.
+ * Calculate the complete length and ensure that it's
+ * positive.
+ */
+ entry->length += length;
+ if (WARN_ON_ONCE(entry->length <= 0))
+ entry->length = length;
+ } else {
+ usbnet_set_skb_tx_stats(skb, 1, length);
+ }
spin_lock_irqsave(&dev->txq.lock, flags);
retval = usb_autopm_get_interface_async(dev->intf);
@@ -220,7 +220,7 @@ struct skb_data { /* skb->cb is one of these */
struct urb *urb;
struct usbnet *dev;
enum skb_state state;
- size_t length;
+ long length;
unsigned long packets;
};
@@ -228,11 +228,13 @@ struct skb_data { /* skb->cb is one of these */
* tx_fixup method before returning an skb.
*/
static inline void
-usbnet_set_skb_tx_stats(struct sk_buff *skb, unsigned long packets)
+usbnet_set_skb_tx_stats(struct sk_buff *skb,
+ unsigned long packets, long bytes_delta)
{
struct skb_data *entry = (struct skb_data *) skb->cb;
entry->packets = packets;
+ entry->length = bytes_delta;
}
extern int usbnet_open(struct net_device *net);
This is a note to let you know that I have just added a patch titled usbnet: Fix tx_bytes statistic running backward in cdc_ncm to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.16.y-queue This patch is scheduled to be released in version 3.16.7-ckt11. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.16.y-ckt tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Luis ------ From 08e0ae0370706aaa18bab048aade89b81470a71e Mon Sep 17 00:00:00 2001 From: Ben Hutchings <ben.hutchings@codethink.co.uk> Date: Wed, 25 Mar 2015 21:41:33 +0100 Subject: usbnet: Fix tx_bytes statistic running backward in cdc_ncm MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit commit 7a1e890e2168e33fb62d84528e996b8b4b478fea upstream. cdc_ncm disagrees with usbnet about how much framing overhead should be counted in the tx_bytes statistics, and tries 'fix' this by decrementing tx_bytes on the transmit path. But statistics must never be decremented except due to roll-over; this will thoroughly confuse user-space. Also, tx_bytes is only incremented by usbnet in the completion path. Fix this by requiring drivers that set FLAG_MULTI_FRAME to set a tx_bytes delta along with the tx_packets count. Fixes: beeecd42c3b4 ("net: cdc_ncm/cdc_mbim: adding NCM protocol statistics") Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Bjørn Mork <bjorn@mork.no> Signed-off-by: Luis Henriques <luis.henriques@canonical.com> --- drivers/net/usb/asix_common.c | 2 +- drivers/net/usb/cdc_ncm.c | 7 +++---- drivers/net/usb/sr9800.c | 2 +- drivers/net/usb/usbnet.c | 16 +++++++++++++--- include/linux/usb/usbnet.h | 6 ++++-- 5 files changed, 22 insertions(+), 11 deletions(-)