linux/net
Eric Dumazet 3b24d854cb tcp/dccp: do not touch listener sk_refcnt under synflood
When a SYNFLOOD targets a non SO_REUSEPORT listener, multiple
cpus contend on sk->sk_refcnt and sk->sk_wmem_alloc changes.

By letting listeners use SOCK_RCU_FREE infrastructure,
we can relax TCP_LISTEN lookup rules and avoid touching sk_refcnt

Note that we still use SLAB_DESTROY_BY_RCU rules for other sockets,
only listeners are impacted by this change.

Peak performance under SYNFLOOD is increased by ~33% :

On my test machine, I could process 3.2 Mpps instead of 2.4 Mpps

Most consuming functions are now skb_set_owner_w() and sock_wfree()
contending on sk->sk_wmem_alloc when cooking SYNACK and freeing them.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-04 22:11:20 -04:00
..
6lowpan 6lowpan: iphc: fix SAM/DAM bit comment 2016-03-10 19:51:29 +01:00
9p net/9p: convert to new CQ API 2016-03-10 20:54:09 -05:00
802
8021q vlan: propagate gso_max_segs 2016-03-17 21:05:01 -04:00
appletalk appletalk: fix erroneous return value 2016-02-18 14:59:34 -05:00
atm
ax25 ax25: add link layer header validation function 2016-03-09 22:13:01 -05:00
batman-adv batman-adv: clarify CFG80211 dependency 2016-03-02 13:45:47 -05:00
bluetooth Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2016-03-19 10:05:34 -07:00
bridge bridge: Allow set bridge ageing time when switchdev disabled 2016-03-30 15:38:13 -04:00
caif net: caif: fix misleading indentation 2016-03-14 13:09:50 -04:00
can sock: enable timestamping using control messages 2016-04-04 15:50:30 -04:00
ceph Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client 2016-03-26 15:53:16 -07:00
core net: add SOCK_RCU_FREE socket flag 2016-04-04 22:11:19 -04:00
dcb
dccp tcp/dccp: do not touch listener sk_refcnt under synflood 2016-04-04 22:11:20 -04:00
decnet
dns_resolver
dsa net: dsa: refine netdev event notifier 2016-03-14 16:05:32 -04:00
ethernet eth: Pull header from first fragment via eth_get_headlen 2016-02-24 13:58:05 -05:00
hsr
ieee802154 ieee802154: 6lowpan: fix return of netdev notifier 2016-02-23 20:29:40 +01:00
ipv4 tcp/dccp: do not touch listener sk_refcnt under synflood 2016-04-04 22:11:20 -04:00
ipv6 tcp/dccp: do not touch listener sk_refcnt under synflood 2016-04-04 22:11:20 -04:00
ipx
irda Merge 4.5-rc4 into tty-next 2016-02-14 14:36:04 -08:00
iucv
kcm kcm: Add receive message timeout 2016-03-09 16:36:15 -05:00
key
l2tp sock: enable timestamping using control messages 2016-04-04 15:50:30 -04:00
l3mdev net: l3mdev: address selection should only consider devices in L3 domain 2016-02-26 14:22:26 -05:00
lapb
llc af_llc: fix types on llc_ui_wait_for_conn 2016-02-17 16:12:13 -05:00
mac80211 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-03-08 12:34:12 -05:00
mac802154 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2016-03-19 10:05:34 -07:00
mpls mpls: autoload lwt module 2016-02-21 22:00:28 -05:00
netfilter tcp/dccp: do not touch listener sk_refcnt under synflood 2016-04-04 22:11:20 -04:00
netlabel netlabel: do not initialise statics to NULL 2016-03-07 11:08:26 -05:00
netlink netlink: add support for NIC driver ioctls 2016-03-22 15:45:44 -04:00
netrom
nfc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2016-03-19 10:05:34 -07:00
openvswitch Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf 2016-03-28 15:38:59 -04:00
packet sock: enable timestamping using control messages 2016-04-04 15:50:30 -04:00
phonet sock: struct proto hash function may error 2016-02-11 03:54:14 -05:00
rds Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2016-03-19 10:05:34 -07:00
rfkill Here's another round of updates for -next: 2016-03-01 17:03:27 -05:00
rose
rxrpc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2016-03-19 10:05:34 -07:00
sched cls_bpf: reset class and reuse major in da 2016-03-18 19:35:21 -04:00
sctp sctp: really allow using GFP_KERNEL on sctp_packet_transmit 2016-03-30 15:41:22 -04:00
sunrpc Various bugfixes, a RDMA update from Chuck Lever, and support for a new 2016-03-24 10:41:00 -07:00
switchdev switchdev: fix typo in comments/doc 2016-03-24 14:51:24 -04:00
tipc tipc: make sure IPv6 header fits in skb headroom 2016-03-14 12:23:12 -04:00
unix Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-02-23 00:09:14 -05:00
vmw_vsock AF_VSOCK: Shrink the area influenced by prepare_to_wait 2016-03-22 16:18:41 -04:00
wimax
wireless Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2016-03-19 10:05:34 -07:00
x25
xfrm xfrm: Fix crash observed during device unregistration and decryption 2016-03-24 14:29:36 -04:00
compat.c
Kconfig Make DST_CACHE a silent config option 2016-03-21 22:56:38 -04:00
Makefile kcm: Kernel Connection Multiplexor module 2016-03-09 16:36:14 -05:00
socket.c sock: enable timestamping using control messages 2016-04-04 15:50:30 -04:00
sysctl_net.c