linux_dsm_epyc7002/drivers/net
Eric Dumazet 0287587884 net: better IFF_XMIT_DST_RELEASE support
Testing xmit_more support with netperf and connected UDP sockets,
I found strange dst refcount false sharing.

Current handling of IFF_XMIT_DST_RELEASE is not optimal.

Dropping dst in validate_xmit_skb() is certainly too late in case
packet was queued by cpu X but dequeued by cpu Y

The logical point to take care of drop/force is in __dev_queue_xmit()
before even taking qdisc lock.

As Julian Anastasov pointed out, need for skb_dst() might come from some
packet schedulers or classifiers.

This patch adds new helper to cleanly express needs of various drivers
or qdiscs/classifiers.

Drivers that need skb_dst() in their ndo_start_xmit() should call
following helper in their setup instead of the prior :

	dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
->
	netif_keep_dst(dev);

Instead of using a single bit, we use two bits, one being
eventually rebuilt in bonding/team drivers.

The other one, is permanent and blocks IFF_XMIT_DST_RELEASE being
rebuilt in bonding/team. Eventually, we could add something
smarter later.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-07 13:22:11 -04:00
..
appletalk net: better IFF_XMIT_DST_RELEASE support 2014-10-07 13:22:11 -04:00
arcnet ARCNET: enable eae arcnet card support 2014-09-29 14:36:26 -04:00
bonding net: better IFF_XMIT_DST_RELEASE support 2014-10-07 13:22:11 -04:00
caif
can drivers/net/can/Kconfig: Let CAN_AT91 depend on HAS_IOMEM 2014-10-03 15:52:03 -07:00
cris
dsa drivers/net/dsa/Kconfig: Let NET_DSA_BCM_SF2 depend on HAS_IOMEM 2014-10-03 15:52:04 -07:00
ethernet net/mlx4_en: remove NETDEV_TX_BUSY 2014-10-07 13:20:39 -04:00
fddi defxx: DEFEA's ESIC port I/O decoding cleanup 2014-09-28 17:22:10 -04:00
hamradio
hippi
hyperv Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2014-10-02 11:25:43 -07:00
ieee802154 mrf24j40: use pr_* / dev_* instead of printk() 2014-09-24 14:14:42 +02:00
irda drivers/net/irda/Kconfig: Let SH_IRDA depend on HAS_IOMEM 2014-10-03 15:52:04 -07:00
phy net: phy: adjust fixed_phy_register() return value 2014-10-07 13:06:45 -04:00
plip
ppp net: better IFF_XMIT_DST_RELEASE support 2014-10-07 13:22:11 -04:00
slip
team net: better IFF_XMIT_DST_RELEASE support 2014-10-07 13:22:11 -04:00
usb r8152: nway reset after setting eee 2014-10-06 17:51:38 -04:00
vmxnet3
wan net: better IFF_XMIT_DST_RELEASE support 2014-10-07 13:22:11 -04:00
wimax
wireless Merge tag 'master-2014-10-02' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next 2014-10-05 21:34:39 -04:00
xen-netback
dummy.c
eql.c net: better IFF_XMIT_DST_RELEASE support 2014-10-07 13:22:11 -04:00
ifb.c net: better IFF_XMIT_DST_RELEASE support 2014-10-07 13:22:11 -04:00
Kconfig openvswitch: fix a compilation error when CONFIG_INET is not setW! 2014-10-07 00:10:49 -04:00
LICENSE.SRC
loopback.c net: better IFF_XMIT_DST_RELEASE support 2014-10-07 13:22:11 -04:00
macvlan.c net: better IFF_XMIT_DST_RELEASE support 2014-10-07 13:22:11 -04:00
macvtap.c macvtap: Fix race between device delete and open. 2014-09-26 15:20:26 -04:00
Makefile
mdio.c
mii.c
netconsole.c
nlmon.c
ntb_netdev.c
rionet.c
sb1000.c
Space.c
sungem_phy.c
tun.c
veth.c
virtio_net.c virtio_net: pass well-formed sgs to virtqueue_add_*() 2014-09-13 12:50:46 -04:00
vxlan.c net: better IFF_XMIT_DST_RELEASE support 2014-10-07 13:22:11 -04:00
xen-netfront.c