kernel_optimize_test/net
Eric Dumazet d26b3a7c4b ipv4: percpu nh_rth_output cache
Input path is mostly run under RCU and doesnt touch dst refcnt

But output path on forwarding or UDP workloads hits
badly dst refcount, and we have lot of false sharing, for example
in ipv4_mtu() when reading rt->rt_pmtu

Using a percpu cache for nh_rth_output gives a nice performance
increase at a small cost.

24 udpflood test on my 24 cpu machine (dummy0 output device)
(each process sends 1.000.000 udp frames, 24 processes are started)

before : 5.24 s
after : 2.06 s
For reference, time on linux-3.5 : 6.60 s

Signed-off-by: Eric Dumazet <edumazet@google.com>
Tested-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-31 14:41:39 -07:00
..
9p net: Fix (nearly-)kernel-doc comments for various functions 2012-07-10 23:13:45 -07:00
802 tokenring: delete all remaining driver support 2012-05-15 20:23:16 -04:00
8021q netpoll: move np->dev and np->dev_name init into __netpoll_setup() 2012-07-17 09:02:36 -07:00
appletalk net: Fix (nearly-)kernel-doc comments for various functions 2012-07-10 23:13:45 -07:00
atm net: Remove casts to same type 2012-06-04 11:45:11 -04:00
ax25 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2012-07-19 11:17:30 -07:00
batman-adv Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2012-07-10 23:56:33 -07:00
bluetooth Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next into for-davem 2012-07-20 12:30:48 -04:00
bridge bridge: make port attributes const 2012-07-30 14:53:22 -07:00
caif Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2012-07-19 11:17:30 -07:00
can can: gw: Remove pointless casts 2012-07-10 22:36:17 +02:00
ceph Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2012-07-24 10:01:50 -07:00
core ipv4: Restore old dst_free() behavior. 2012-07-31 14:41:38 -07:00
dcb net: Fix non-kernel-doc comments with kernel-doc start marker 2012-07-10 23:13:45 -07:00
dccp ipv4: Prepare for change of rt->rt_iif encoding. 2012-07-23 16:36:26 -07:00
decnet ipv4: Restore old dst_free() behavior. 2012-07-31 14:41:38 -07:00
dns_resolver Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2012-05-21 20:27:36 -07:00
dsa dsa: Convert compare_ether_addr to ether_addr_equal 2012-05-09 20:49:19 -04:00
ethernet ipx: move peII functions 2012-07-19 10:48:00 -07:00
ieee802154 6lowpan: Change byte order when storing/accessing to len field 2012-07-16 22:52:02 -07:00
ipv4 ipv4: percpu nh_rth_output cache 2012-07-31 14:41:39 -07:00
ipv6 net: TCP early demux cleanup 2012-07-30 14:53:21 -07:00
ipx ipx: move peII functions 2012-07-19 10:48:00 -07:00
irda irda: Fix typo in irda 2012-07-16 23:23:52 -07:00
iucv net: remove skb_orphan_try() 2012-06-15 15:30:15 -07:00
key
l2tp net: l2tp_eth: provide tx_dropped counter 2012-06-29 00:52:32 -07:00
lapb lapb: Neaten debugging 2012-05-17 18:45:20 -04:00
llc net: Fix (nearly-)kernel-doc comments for various functions 2012-07-10 23:13:45 -07:00
mac80211 Merge branch 'for-3.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/cooloney/linux-leds 2012-07-26 20:26:27 -07:00
mac802154 mac802154: sparse warnings: make symbols static 2012-07-12 07:54:45 -07:00
netfilter Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2012-07-19 11:17:30 -07:00
netlabel
netlink genetlink: define lockdep_genl_is_held() when CONFIG_LOCKDEP 2012-07-24 00:01:30 -07:00
netrom
nfc Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next into for-davem 2012-07-20 12:30:48 -04:00
openvswitch Revert "openvswitch: potential NULL deref in sample()" 2012-07-27 13:45:51 -07:00
packet net: added support for 40GbE link. 2012-06-27 15:42:24 -07:00
phonet net: remove my future former mail address 2012-06-17 16:29:38 -07:00
rds rds: set correct msg_namelen 2012-07-23 01:01:44 -07:00
rfkill rfkill: Add the capability to switch all devices of all type in __rfkill_switch_all(). 2012-06-06 15:18:17 -04:00
rose
rxrpc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2012-07-10 23:56:33 -07:00
sched ipv4: Prepare for change of rt->rt_iif encoding. 2012-07-23 16:36:26 -07:00
sctp ipv4: Prepare for change of rt->rt_iif encoding. 2012-07-23 16:36:26 -07:00
sunrpc ipv6: add ipv6_addr_hash() helper 2012-07-18 11:28:46 -07:00
tipc tipc: remove print_buf and deprecated log buffer code 2012-07-13 19:34:43 -04:00
unix net: make sock diag per-namespace 2012-07-16 22:31:34 -07:00
wanrouter wanmain: comparing array with NULL 2012-07-24 13:55:21 -07:00
wimax
wireless Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next into for-davem 2012-07-20 12:30:48 -04:00
x25 net: Fix (nearly-)kernel-doc comments for various functions 2012-07-10 23:13:45 -07:00
xfrm net: Document dst->obsolete better. 2012-07-20 13:31:21 -07:00
compat.c net: Fix references to out-of-scope variables in put_cmsg_compat() 2012-07-22 17:50:49 -07:00
Kconfig net: drop NET dependency from HAVE_BPF_JIT 2012-05-21 12:50:12 -07:00
Makefile econet: remove ancient bug ridden protocol 2012-05-18 01:35:08 -04:00
nonet.c
socket.c net: netprio_cgroup: rework update socket logic 2012-07-22 12:44:01 -07:00
sysctl_net.c net: delete all instances of special processing for token ring 2012-05-15 20:14:35 -04:00