Krishna Kumar bbd8a0d3a3 net: Avoid enqueuing skb for default qdiscs ... dev_queue_xmit enqueue's a skb and calls qdisc_run which dequeue's the skb and xmits it. In most cases, the skb that is enqueue'd is the same one that is dequeue'd (unless the queue gets stopped or multiple cpu's write to the same queue and ends in a race with qdisc_run). For default qdiscs, we can remove the redundant enqueue/dequeue and simply xmit the skb since the default qdisc is work-conserving. The patch uses a new flag - TCQ_F_CAN_BYPASS to identify the default fast queue. The controversial part of the patch is incrementing qlen when a skb is requeued - this is to avoid checks like the second line below: + } else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) && >> !q->gso_skb && + !test_and_set_bit(__QDISC_STATE_RUNNING, &q->state)) { Results of a 2 hour testing for multiple netperf sessions (1, 2, 4, 8, 12 sessions on a 4 cpu system-X). The BW numbers are aggregate Mb/s across iterations tested with this version on System-X boxes with Chelsio 10gbps cards: ---------------------------------- Size | ORG BW NEW BW | ---------------------------------- 128K | 156964 159381 | 256K | 158650 162042 | ---------------------------------- Changes from ver1: 1. Move sch_direct_xmit declaration from sch_generic.h to pkt_sched.h 2. Update qdisc basic statistics for direct xmit path. 3. Set qlen to zero in qdisc_reset. 4. Changed some function names to more meaningful ones. Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>		2009-08-06 20:10:18 -07:00
..
9p	net/9p: handle correctly interrupted 9P requests	2009-04-05 16:54:53 -05:00
bluetooth	Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/holtmann/bluetooth-next-2.6	2009-06-11 05:47:43 -07:00
irda	net: mark read-only arrays as const	2009-08-05 10:42:58 -07:00
iucv	af_iucv: Return -EAGAIN if iucv msg limit is exceeded	2009-06-19 00:10:40 -07:00
netfilter	netfilter: tcp conntrack: fix unacknowledged data detection with NAT	2009-06-29 14:07:56 +02:00
netns	net, netns_xt: shrink netns_xt members	2009-07-05 19:16:18 -07:00
phonet	Phonet: sockets list through proc_fs	2009-07-23 17:58:19 -07:00
sctp	net: mark read-only arrays as const	2009-08-05 10:42:58 -07:00
tc_act	pkt_action: add new action skbedit	2008-09-12 16:30:20 -07:00
tipc	tipc: Remove unneeded parameter to tipc_createport_raw()	2008-07-14 22:42:19 -07:00
act_api.h	[NET_SCHED]: act_api: use PTR_ERR in tcf_action_init/tcf_action_get	2008-01-28 15:11:17 -08:00
addrconf.h	ipv6: Fix conflict resolutions during ipv6 binding	2009-03-24 19:49:11 -07:00
af_ieee802154.h	ieee802154: move headers out of extra directory	2009-07-23 17:08:51 +04:00
af_rxrpc.h
af_unix.h	net: Fix soft lockups/OOM issues w/ unix garbage collector	2008-11-26 15:32:27 -08:00
ah.h
arp.h	[NETFILTER]: ebtables: remove casts, use consts	2008-01-31 19:27:33 -08:00
atmclip.h	clip: convert to internal network_device_stats	2009-01-21 14:01:59 -08:00
ax25.h	[AX25] ax25_ds_timer: use mod_timer instead of add_timer	2008-02-12 17:53:34 -08:00
ax88796.h	ax88796: Add method to take MAC from platform data	2009-03-24 23:32:03 -07:00
cfg80211.h	cfg80211: enable country IE support to all cfg80211 drivers	2009-08-04 16:44:19 -04:00
checksum.h	include/net net/ - csum_partial - remove unnecessary casts	2008-11-19 15:44:53 -08:00
cipso_ipv4.h	netlabel: Label incoming TCP connections correctly in SELinux	2009-03-28 15:01:36 +11:00
compat.h	net: Use standard structures for generic socket address structures.	2008-07-19 22:35:47 -07:00
datalink.h
dcbnl.h	net: fix DCB setstate to return success/failure	2008-12-21 20:09:50 -08:00
dn_dev.h
dn_fib.h	decnet: remove private wrappers of endian helpers	2008-11-27 00:12:47 -08:00
dn_neigh.h
dn_nsp.h
dn_route.h
dn.h	decnet: compile fix for removal of byteorder wrapper	2008-11-27 23:04:13 -08:00
dsa.h	dsa: add switch chip cascading support	2009-03-21 19:06:54 -07:00
dsfield.h
dst.h	net: skb->dst accessors	2009-06-03 02:51:04 -07:00
esp.h	[IPSEC]: Use crypto_aead and authenc in ESP	2008-01-31 19:27:02 -08:00
ethoc.h	net: Add support for the OpenCores 10/100 Mbps Ethernet MAC.	2009-03-27 00:16:21 -07:00
fib_rules.h	net: Remove unused parameter from fill method in fib_rules_ops.	2009-05-20 17:26:23 -07:00
flow.h	netns xfrm: lookup in netns	2008-11-25 17:35:18 -08:00
garp.h	vlan: Add GVRP support	2008-07-05 21:26:57 -07:00
gen_stats.h	pkt_sched: gen_estimator: Optimize gen_estimator_active()	2008-11-26 15:24:32 -08:00
genetlink.h	genetlink: make netns aware	2009-07-12 14:03:27 -07:00
icmp.h	mib: put icmpmsg statistics on struct net	2008-07-18 04:04:22 -07:00
ieee80211_radiotap.h	wireless: radiotap updates	2009-03-27 20:12:52 -04:00
ieee802154_netdev.h	ieee802154: move headers out of extra directory	2009-07-23 17:08:51 +04:00
ieee802154.h	ieee802154: move headers out of extra directory	2009-07-23 17:08:51 +04:00
if_inet6.h	ipv6: reorder struct inet6_ifaddr to remove padding on 64 bit builds	2009-03-21 13:29:05 -07:00
inet6_connection_sock.h
inet6_hashtables.h	net: skb->dst accessors	2009-06-03 02:51:04 -07:00
inet_common.h	[NETNS]: Inet control socket should not hold a namespace.	2008-04-03 14:28:30 -07:00
inet_connection_sock.h	net: more #ifdef CONFIG_COMPAT	2008-08-28 02:53:51 -07:00
inet_ecn.h	net: replace __constant_{endian} uses in net headers	2009-02-14 22:58:35 -08:00
inet_frag.h	inet fragments: fix sparse warning: context imbalance	2009-02-26 23:13:35 -08:00
inet_hashtables.h	net: skb->dst accessors	2009-06-03 02:51:04 -07:00
inet_sock.h	Merge branch 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/vegard/kmemcheck	2009-06-16 13:09:51 -07:00
inet_timewait_sock.h	net: annotate inet_timewait_sock bitfields	2009-06-15 15:49:32 +02:00
inetpeer.h	net: remove CVS keywords	2008-06-11 21:00:38 -07:00
ip6_checksum.h
ip6_fib.h	xfrm: select sane defaults for xfrm[4|6] gc_thresh	2009-07-30 18:52:15 -07:00
ip6_route.h	net: skb->dst accessors	2009-06-03 02:51:04 -07:00
ip6_tunnel.h	net: remove CVS keywords	2008-06-11 21:00:38 -07:00
ip_fib.h	ipv4: remove unused macro (FIB_RES_RESET) from ip_fib.h.	2009-05-03 14:19:51 -07:00
ip_vs.h	net: mark read-only arrays as const	2009-08-05 10:42:58 -07:00
ip.h	snmp: add missing counters for RFC 4293	2009-04-27 02:45:02 -07:00
ipcomp.h	ipsec: ipcomp - Merge IPComp implementations	2008-07-25 02:54:40 -07:00
ipconfig.h	net: remove CVS keywords	2008-06-11 21:00:38 -07:00
ipip.h	sit: stateless autoconf for isatap	2009-05-19 16:02:02 -07:00
ipv6.h	udpv6: Remove unused skb argument of ipv6_select_ident()	2009-07-12 14:29:28 -07:00
ipx.h	net: replace __constant_{endian} uses in net headers	2009-02-14 22:58:35 -08:00
iw_handler.h	wext: constify extra argument to wireless_send_event	2009-07-10 15:01:49 -04:00
lapb.h
lib80211.h	wireless: missing include in lib80211.h	2008-11-21 11:42:55 -05:00
llc_c_ac.h
llc_c_ev.h
llc_c_st.h
llc_conn.h
llc_if.h	[LLC]: Kill static inline llc_addrany	2008-02-29 11:46:17 -08:00
llc_pdu.h	[LLC]: skb allocation size for responses	2008-03-31 21:02:47 -07:00
llc_s_ac.h
llc_s_ev.h
llc_s_st.h
llc_sap.h	[LLC]: skb allocation size for responses	2008-03-31 21:02:47 -07:00
llc.h	[LLC]: station source mac address	2008-03-28 16:28:36 -07:00
mac80211.h	mac80211: FIF_PSPOLL filter flag	2009-08-04 16:44:35 -04:00
mip6.h	[IPV6] MIP6: Use our standard definitions for paddings.	2008-04-12 13:43:22 +09:00
ndisc.h	ipv6: Fix sporadic sendmsg -EINVAL when sending to multicast groups.	2009-01-04 16:04:39 -08:00
neighbour.h	neigh: Convert garbage collection from softirq to workqueue	2009-08-02 18:35:16 -07:00
net_namespace.h	net: explain netns notifiers a little better	2009-07-20 08:03:00 -07:00
netdma.h	net_dma: convert to dma_find_channel	2009-01-06 11:38:15 -07:00
netevent.h
netlabel.h	netlabel: Cleanup the Smack/NetLabel code to fix incoming TCP connections	2009-03-28 15:01:37 +11:00
netlink.h	netfilter: conntrack: add support for DCCP handshake sequence to ctnetlink	2009-05-27 17:50:35 +02:00
netrom.h	netrom: convert to internal net_device_stats	2009-01-21 14:02:01 -08:00
nexthop.h
nl802154.h	ieee802154: move headers out of extra directory	2009-07-23 17:08:51 +04:00
p8022.h
pkt_cls.h	ematch: simpler tcf_em_unregister()	2008-11-16 23:01:49 -08:00
pkt_sched.h	net: Avoid enqueuing skb for default qdiscs	2009-08-06 20:10:18 -07:00
protocol.h	ipv6: Use correct data types for ICMPv6 type and code	2009-06-23 04:31:07 -07:00
psnap.h	snap: use const for descriptor	2009-03-21 19:06:50 -07:00
raw.h	[RAW]: Add raw_hashinfo member on struct proto.	2008-03-22 16:56:51 -07:00
rawv6.h	ipv6: Use correct data types for ICMPv6 type and code	2009-06-23 04:31:07 -07:00
red.h
regulatory.h	cfg80211: clean up includes	2009-04-22 16:57:17 -04:00
request_sock.h	net: Fix memory leak in the proto_register function	2008-11-21 16:45:22 -08:00
rose.h	NET: ROSE: Don't use static buffer.	2009-07-26 19:11:14 -07:00
route.h	net: skb->rtable accessor	2009-06-03 02:51:02 -07:00
rtnetlink.h	[RTNL]: Introduce the rtnl_kill_links helper.	2008-04-16 00:46:52 -07:00
sch_generic.h	net: Avoid enqueuing skb for default qdiscs	2009-08-06 20:10:18 -07:00
scm.h	cleanup: remove unused member in scm_cookie.	2009-07-05 19:16:10 -07:00
slhc_vj.h
snmp.h	snmp: add missing counters for RFC 4293	2009-04-27 02:45:02 -07:00
sock.h	net: sock_copy() fixes	2009-07-16 18:05:26 -07:00
stp.h	net: Add STP demux layer	2008-07-05 21:25:39 -07:00
tcp_states.h
tcp.h	tcp: Fix MD5 signature checking on IPv4 mapped sockets	2009-07-20 07:49:07 -07:00
timewait_sock.h	net: Fix memory leak in the proto_register function	2008-11-21 16:45:22 -08:00
transp_v6.h	net: replace __constant_{endian} uses in net headers	2009-02-14 22:58:35 -08:00
udp.h	udpv4: Handle large incoming UDP/IPv4 packets and support software UFO.	2009-07-12 14:29:21 -07:00
udplite.h	udp: introduce struct udp_table and multiple spinlocks	2008-10-29 01:41:45 -07:00
wext.h	wext: Dispatch and handle compat ioctls entirely in net/wireless/wext.c	2008-06-16 18:32:46 -07:00
wimax.h	rfkill: rewrite	2009-06-03 14:06:13 -04:00
x25.h	x25: Fix sleep from timer on socket destroy.	2009-06-16 05:40:30 -07:00
x25device.h
xfrm.h	xfrm: select sane defaults for xfrm[4|6] gc_thresh	2009-07-30 18:52:15 -07:00