aboutsummaryrefslogtreecommitdiffstats
path: root/target/linux/generic/backport-4.9/023-7-kaweth-use-skb_cow_head-to-deal-with-cloned-skbs.patch
diff options
context:
space:
mode:
authorJohn Crispin <john@phrozen.org>2016-12-25 20:11:34 +0100
committerJohn Crispin <john@phrozen.org>2017-08-05 08:46:36 +0200
commit74d00a8c3849c1340efd713eb94b786e304c201f (patch)
treede481743de61c34da96ab5f9dba3af3edcfb8260 /target/linux/generic/backport-4.9/023-7-kaweth-use-skb_cow_head-to-deal-with-cloned-skbs.patch
parentde350550ef648d9728351b986b0516fa29465c45 (diff)
downloadupstream-74d00a8c3849c1340efd713eb94b786e304c201f.tar.gz
upstream-74d00a8c3849c1340efd713eb94b786e304c201f.tar.bz2
upstream-74d00a8c3849c1340efd713eb94b786e304c201f.zip
kernel: split patches folder up into backport, pending and hack folders
* properly format/comment all patches * merge debloat patches * merge Kconfig patches * merge swconfig patches * merge hotplug patches * drop 200-fix_localversion.patch - upstream * drop 222-arm_zimage_none.patch - unused * drop 252-mv_cesa_depends.patch - no longer required * drop 410-mtd-move-forward-declaration-of-struct-mtd_info.patch - unused * drop 661-fq_codel_keep_dropped_stats.patch - outdated * drop 702-phy_add_aneg_done_function.patch - upstream * drop 840-rtc7301.patch - unused * drop 841-rtc_pt7c4338.patch - upstream * drop 921-use_preinit_as_init.patch - unused * drop spio-gpio-old and gpio-mmc - unused Signed-off-by: John Crispin <john@phrozen.org>
Diffstat (limited to 'target/linux/generic/backport-4.9/023-7-kaweth-use-skb_cow_head-to-deal-with-cloned-skbs.patch')
-rw-r--r--target/linux/generic/backport-4.9/023-7-kaweth-use-skb_cow_head-to-deal-with-cloned-skbs.patch43
1 files changed, 43 insertions, 0 deletions
diff --git a/target/linux/generic/backport-4.9/023-7-kaweth-use-skb_cow_head-to-deal-with-cloned-skbs.patch b/target/linux/generic/backport-4.9/023-7-kaweth-use-skb_cow_head-to-deal-with-cloned-skbs.patch
new file mode 100644
index 0000000000..597f25b21d
--- /dev/null
+++ b/target/linux/generic/backport-4.9/023-7-kaweth-use-skb_cow_head-to-deal-with-cloned-skbs.patch
@@ -0,0 +1,43 @@
+From 39fba7835aacda65284a86e611774cbba71dac20 Mon Sep 17 00:00:00 2001
+From: Eric Dumazet <edumazet@google.com>
+Date: Wed, 19 Apr 2017 09:59:26 -0700
+Subject: [PATCH] kaweth: use skb_cow_head() to deal with cloned skbs
+
+We can use skb_cow_head() to properly deal with clones,
+especially the ones coming from TCP stack that allow their head being
+modified. This avoids a copy.
+
+Signed-off-by: Eric Dumazet <edumazet@google.com>
+Cc: James Hughes <james.hughes@raspberrypi.org>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ drivers/net/usb/kaweth.c | 18 ++++++------------
+ 1 file changed, 6 insertions(+), 12 deletions(-)
+
+--- a/drivers/net/usb/kaweth.c
++++ b/drivers/net/usb/kaweth.c
+@@ -803,18 +803,12 @@ static netdev_tx_t kaweth_start_xmit(str
+ }
+
+ /* We now decide whether we can put our special header into the sk_buff */
+- if (skb_cloned(skb) || skb_headroom(skb) < 2) {
+- /* no such luck - we make our own */
+- struct sk_buff *copied_skb;
+- copied_skb = skb_copy_expand(skb, 2, 0, GFP_ATOMIC);
+- dev_kfree_skb_irq(skb);
+- skb = copied_skb;
+- if (!copied_skb) {
+- kaweth->stats.tx_errors++;
+- netif_start_queue(net);
+- spin_unlock_irq(&kaweth->device_lock);
+- return NETDEV_TX_OK;
+- }
++ if (skb_cow_head(skb, 2)) {
++ kaweth->stats.tx_errors++;
++ netif_start_queue(net);
++ spin_unlock_irq(&kaweth->device_lock);
++ dev_kfree_skb_any(skb);
++ return NETDEV_TX_OK;
+ }
+
+ private_header = (__le16 *)__skb_push(skb, 2);