linux_kernel/net/sched/Kconfig

#
# Traffic control configuration.
# 

menuconfig NET_SCHED
	bool "QoS and/or fair queueing"
	select NET_SCH_FIFO
	---help---
	  When the kernel has several packets to send out over a network
	  device, it has to decide which ones to send first, which ones to
	  delay, and which ones to drop. This is the job of the queueing
	  disciplines, several different algorithms for how to do this
	  "fairly" have been proposed.

	  If you say N here, you will get the standard packet scheduler, which
	  is a FIFO (first come, first served). If you say Y here, you will be
	  able to choose from among several alternative algorithms which can
	  then be attached to different network devices. This is useful for
	  example if some of your network devices are real time devices that
	  need a certain minimum data flow rate, or if you need to limit the
	  maximum data flow rate for traffic which matches specified criteria.
	  This code is considered to be experimental.

	  To administer these schedulers, you'll need the user-level utilities
	  from the package iproute2+tc at <ftp://ftp.tux.org/pub/net/ip-routing/>.
	  That package also contains some documentation; for more, check out
	  <http://www.linuxfoundation.org/collaborate/workgroups/networking/iproute2>.

	  This Quality of Service (QoS) support will enable you to use
	  Differentiated Services (diffserv) and Resource Reservation Protocol
	  (RSVP) on your Linux router if you also say Y to the corresponding
	  classifiers below.  Documentation and software is at
	  <http://diffserv.sourceforge.net/>.

	  If you say Y here and to "/proc file system" below, you will be able
	  to read status information about packet schedulers from the file
	  /proc/net/psched.

	  The available schedulers are listed in the following questions; you
	  can say Y to as many as you like. If unsure, say N now.

if NET_SCHED

comment "Queueing/Scheduling"

config NET_SCH_CBQ
	tristate "Class Based Queueing (CBQ)"
	---help---
	  Say Y here if you want to use the Class-Based Queueing (CBQ) packet
	  scheduling algorithm. This algorithm classifies the waiting packets
	  into a tree-like hierarchy of classes; the leaves of this tree are
	  in turn scheduled by separate algorithms.

	  See the top of <file:net/sched/sch_cbq.c> for more details.

	  CBQ is a commonly used scheduler, so if you're unsure, you should
	  say Y here. Then say Y to all the queueing algorithms below that you
	  want to use as leaf disciplines.

	  To compile this code as a module, choose M here: the
	  module will be called sch_cbq.

config NET_SCH_HTB
	tristate "Hierarchical Token Bucket (HTB)"
	---help---
	  Say Y here if you want to use the Hierarchical Token Buckets (HTB)
	  packet scheduling algorithm. See
	  <http://luxik.cdi.cz/~devik/qos/htb/> for complete manual and
	  in-depth articles.

	  HTB is very similar to CBQ regarding its goals however is has
	  different properties and different algorithm.

	  To compile this code as a module, choose M here: the
	  module will be called sch_htb.

config NET_SCH_HFSC
	tristate "Hierarchical Fair Service Curve (HFSC)"
	---help---
	  Say Y here if you want to use the Hierarchical Fair Service Curve
	  (HFSC) packet scheduling algorithm.

	  To compile this code as a module, choose M here: the
	  module will be called sch_hfsc.

config NET_SCH_ATM
	tristate "ATM Virtual Circuits (ATM)"
	depends on ATM
	---help---
	  Say Y here if you want to use the ATM pseudo-scheduler.  This
	  provides a framework for invoking classifiers, which in turn
	  select classes of this queuing discipline.  Each class maps
	  the flow(s) it is handling to a given virtual circuit.

	  See the top of <file:net/sched/sch_atm.c> for more details.

	  To compile this code as a module, choose M here: the
	  module will be called sch_atm.

config NET_SCH_PRIO
	tristate "Multi Band Priority Queueing (PRIO)"
	---help---
	  Say Y here if you want to use an n-band priority queue packet
	  scheduler.

	  To compile this code as a module, choose M here: the
	  module will be called sch_prio.

config NET_SCH_MULTIQ
	tristate "Hardware Multiqueue-aware Multi Band Queuing (MULTIQ)"
	---help---
	  Say Y here if you want to use an n-band queue packet scheduler
	  to support devices that have multiple hardware transmit queues.

	  To compile this code as a module, choose M here: the
	  module will be called sch_multiq.

config NET_SCH_RED
	tristate "Random Early Detection (RED)"
	---help---
	  Say Y here if you want to use the Random Early Detection (RED)
	  packet scheduling algorithm.

	  See the top of <file:net/sched/sch_red.c> for more details.

	  To compile this code as a module, choose M here: the
	  module will be called sch_red.

config NET_SCH_SFB
	tristate "Stochastic Fair Blue (SFB)"
	---help---
	  Say Y here if you want to use the Stochastic Fair Blue (SFB)
	  packet scheduling algorithm.

	  See the top of <file:net/sched/sch_sfb.c> for more details.

	  To compile this code as a module, choose M here: the
	  module will be called sch_sfb.

config NET_SCH_SFQ
	tristate "Stochastic Fairness Queueing (SFQ)"
	---help---
	  Say Y here if you want to use the Stochastic Fairness Queueing (SFQ)
	  packet scheduling algorithm.

	  See the top of <file:net/sched/sch_sfq.c> for more details.

	  To compile this code as a module, choose M here: the
	  module will be called sch_sfq.

config NET_SCH_TEQL
	tristate "True Link Equalizer (TEQL)"
	---help---
	  Say Y here if you want to use the True Link Equalizer (TLE) packet
	  scheduling algorithm. This queueing discipline allows the combination
	  of several physical devices into one virtual device.

	  See the top of <file:net/sched/sch_teql.c> for more details.

	  To compile this code as a module, choose M here: the
	  module will be called sch_teql.

config NET_SCH_TBF
	tristate "Token Bucket Filter (TBF)"
	---help---
	  Say Y here if you want to use the Token Bucket Filter (TBF) packet
	  scheduling algorithm.

	  See the top of <file:net/sched/sch_tbf.c> for more details.

	  To compile this code as a module, choose M here: the
	  module will be called sch_tbf.

config NET_SCH_GRED
	tristate "Generic Random Early Detection (GRED)"
	---help---
	  Say Y here if you want to use the Generic Random Early Detection
	  (GRED) packet scheduling algorithm for some of your network devices
	  (see the top of <file:net/sched/sch_red.c> for details and
	  references about the algorithm).

	  To compile this code as a module, choose M here: the
	  module will be called sch_gred.

config NET_SCH_DSMARK
	tristate "Differentiated Services marker (DSMARK)"
	---help---
	  Say Y if you want to schedule packets according to the
	  Differentiated Services architecture proposed in RFC 2475.
	  Technical information on this method, with pointers to associated
	  RFCs, is available at <http://www.gta.ufrj.br/diffserv/>.

	  To compile this code as a module, choose M here: the
	  module will be called sch_dsmark.

config NET_SCH_NETEM
	tristate "Network emulator (NETEM)"
	---help---
	  Say Y if you want to emulate network delay, loss, and packet
	  re-ordering. This is often useful to simulate networks when
	  testing applications or protocols.

	  To compile this driver as a module, choose M here: the module
	  will be called sch_netem.

	  If unsure, say N.

config NET_SCH_DRR
	tristate "Deficit Round Robin scheduler (DRR)"
	help
	  Say Y here if you want to use the Deficit Round Robin (DRR) packet
	  scheduling algorithm.

	  To compile this driver as a module, choose M here: the module
	  will be called sch_drr.

	  If unsure, say N.

config NET_SCH_MQPRIO
	tristate "Multi-queue priority scheduler (MQPRIO)"
	help
	  Say Y here if you want to use the Multi-queue Priority scheduler.
	  This scheduler allows QOS to be offloaded on NICs that have support
	  for offloading QOS schedulers.

	  To compile this driver as a module, choose M here: the module will
	  be called sch_mqprio.

	  If unsure, say N.

config NET_SCH_CHOKE
	tristate "CHOose and Keep responsive flow scheduler (CHOKE)"
	help
	  Say Y here if you want to use the CHOKe packet scheduler (CHOose
	  and Keep for responsive flows, CHOose and Kill for unresponsive
	  flows). This is a variation of RED which trys to penalize flows
	  that monopolize the queue.

	  To compile this code as a module, choose M here: the
	  module will be called sch_choke.

config NET_SCH_QFQ
	tristate "Quick Fair Queueing scheduler (QFQ)"
	help
	  Say Y here if you want to use the Quick Fair Queueing Scheduler (QFQ)
	  packet scheduling algorithm.

	  To compile this driver as a module, choose M here: the module
	  will be called sch_qfq.

	  If unsure, say N.

config NET_SCH_CODEL
	tristate "Controlled Delay AQM (CODEL)"
	help
	  Say Y here if you want to use the Controlled Delay (CODEL)
	  packet scheduling algorithm.

	  To compile this driver as a module, choose M here: the module
	  will be called sch_codel.

	  If unsure, say N.

config NET_SCH_FQ_CODEL
	tristate "Fair Queue Controlled Delay AQM (FQ_CODEL)"
	help
	  Say Y here if you want to use the FQ Controlled Delay (FQ_CODEL)
	  packet scheduling algorithm.

	  To compile this driver as a module, choose M here: the module
	  will be called sch_fq_codel.

	  If unsure, say N.

config NET_SCH_FQ
	tristate "Fair Queue"
	help
	  Say Y here if you want to use the FQ packet scheduling algorithm.

	  FQ does flow separation, and is able to respect pacing requirements
	  set by TCP stack into sk->sk_pacing_rate (for localy generated
	  traffic)

	  To compile this driver as a module, choose M here: the module
	  will be called sch_fq.

	  If unsure, say N.

config NET_SCH_HHF
	tristate "Heavy-Hitter Filter (HHF)"
	help
	  Say Y here if you want to use the Heavy-Hitter Filter (HHF)
	  packet scheduling algorithm.

	  To compile this driver as a module, choose M here: the module
	  will be called sch_hhf.

config NET_SCH_PIE
	tristate "Proportional Integral controller Enhanced (PIE) scheduler"
	help
	  Say Y here if you want to use the Proportional Integral controller
	  Enhanced scheduler packet scheduling algorithm.
	  For more information, please see
	  http://tools.ietf.org/html/draft-pan-tsvwg-pie-00

	  To compile this driver as a module, choose M here: the module
	  will be called sch_pie.

	  If unsure, say N.

config NET_SCH_INGRESS
	tristate "Ingress Qdisc"
	depends on NET_CLS_ACT
	---help---
	  Say Y here if you want to use classifiers for incoming packets.
	  If unsure, say Y.

	  To compile this code as a module, choose M here: the
	  module will be called sch_ingress.

config NET_SCH_PLUG
	tristate "Plug network traffic until release (PLUG)"
	---help---

	  This queuing discipline allows userspace to plug/unplug a network
	  output queue, using the netlink interface.  When it receives an
	  enqueue command it inserts a plug into the outbound queue that
	  causes following packets to enqueue until a dequeue command arrives
	  over netlink, causing the plug to be removed and resuming the normal
	  packet flow.

	  This module also provides a generic "network output buffering"
	  functionality (aka output commit), wherein upon arrival of a dequeue
	  command, only packets up to the first plug are released for delivery.
	  The Remus HA project uses this module to enable speculative execution
	  of virtual machines by allowing the generated network output to be rolled
	  back if needed.

	  For more information, please refer to http://wiki.xensource.com/xenwiki/Remus

	  Say Y here if you are using this kernel for Xen dom0 and
	  want to protect Xen guests with Remus.

	  To compile this code as a module, choose M here: the
	  module will be called sch_plug.

comment "Classification"

config NET_CLS
	boolean

config NET_CLS_BASIC
	tristate "Elementary classification (BASIC)"
	select NET_CLS
	---help---
	  Say Y here if you want to be able to classify packets using
	  only extended matches and actions.

	  To compile this code as a module, choose M here: the
	  module will be called cls_basic.

config NET_CLS_TCINDEX
	tristate "Traffic-Control Index (TCINDEX)"
	select NET_CLS
	---help---
	  Say Y here if you want to be able to classify packets based on
	  traffic control indices. You will want this feature if you want
	  to implement Differentiated Services together with DSMARK.

	  To compile this code as a module, choose M here: the
	  module will be called cls_tcindex.

config NET_CLS_ROUTE4
	tristate "Routing decision (ROUTE)"
	depends on INET
	select IP_ROUTE_CLASSID
	select NET_CLS
	---help---
	  If you say Y here, you will be able to classify packets
	  according to the route table entry they matched.

	  To compile this code as a module, choose M here: the
	  module will be called cls_route.

config NET_CLS_FW
	tristate "Netfilter mark (FW)"
	select NET_CLS
	---help---
	  If you say Y here, you will be able to classify packets
	  according to netfilter/firewall marks.

	  To compile this code as a module, choose M here: the
	  module will be called cls_fw.

config NET_CLS_U32
	tristate "Universal 32bit comparisons w/ hashing (U32)"
	select NET_CLS
	---help---
	  Say Y here to be able to classify packets using a universal
	  32bit pieces based comparison scheme.

	  To compile this code as a module, choose M here: the
	  module will be called cls_u32.

config CLS_U32_PERF
	bool "Performance counters support"
	depends on NET_CLS_U32
	---help---
	  Say Y here to make u32 gather additional statistics useful for
	  fine tuning u32 classifiers.

config CLS_U32_MARK
	bool "Netfilter marks support"
	depends on NET_CLS_U32
	---help---
	  Say Y here to be able to use netfilter marks as u32 key.

config NET_CLS_RSVP
	tristate "IPv4 Resource Reservation Protocol (RSVP)"
	select NET_CLS
	---help---
	  The Resource Reservation Protocol (RSVP) permits end systems to
	  request a minimum and maximum data flow rate for a connection; this
	  is important for real time data such as streaming sound or video.

	  Say Y here if you want to be able to classify outgoing packets based
	  on their RSVP requests.

	  To compile this code as a module, choose M here: the
	  module will be called cls_rsvp.

config NET_CLS_RSVP6
	tristate "IPv6 Resource Reservation Protocol (RSVP6)"
	select NET_CLS
	---help---
	  The Resource Reservation Protocol (RSVP) permits end systems to
	  request a minimum and maximum data flow rate for a connection; this
	  is important for real time data such as streaming sound or video.

	  Say Y here if you want to be able to classify outgoing packets based
	  on their RSVP requests and you are using the IPv6 protocol.

	  To compile this code as a module, choose M here: the
	  module will be called cls_rsvp6.

config NET_CLS_FLOW
	tristate "Flow classifier"
	select NET_CLS
	---help---
	  If you say Y here, you will be able to classify packets based on
	  a configurable combination of packet keys. This is mostly useful
	  in combination with SFQ.

	  To compile this code as a module, choose M here: the
	  module will be called cls_flow.

config NET_CLS_CGROUP
	tristate "Control Group Classifier"
	select NET_CLS
	select CGROUP_NET_CLASSID
	depends on CGROUPS
	---help---
	  Say Y here if you want to classify packets based on the control
	  cgroup of their process.

	  To compile this code as a module, choose M here: the
	  module will be called cls_cgroup.

config NET_CLS_BPF
	tristate "BPF-based classifier"
	select NET_CLS
	---help---
	  If you say Y here, you will be able to classify packets based on
	  programmable BPF (JIT'ed) filters as an alternative to ematches.

	  To compile this code as a module, choose M here: the module will
	  be called cls_bpf.

config NET_EMATCH
	bool "Extended Matches"
	select NET_CLS
	---help---
	  Say Y here if you want to use extended matches on top of classifiers
	  and select the extended matches below.

	  Extended matches are small classification helpers not worth writing
	  a separate classifier for.

	  A recent version of the iproute2 package is required to use
	  extended matches.

config NET_EMATCH_STACK
	int "Stack size"
	depends on NET_EMATCH
	default "32"
	---help---
	  Size of the local stack variable used while evaluating the tree of
	  ematches. Limits the depth of the tree, i.e. the number of
	  encapsulated precedences. Every level requires 4 bytes of additional
	  stack space.

config NET_EMATCH_CMP
	tristate "Simple packet data comparison"
	depends on NET_EMATCH
	---help---
	  Say Y here if you want to be able to classify packets based on
	  simple packet data comparisons for 8, 16, and 32bit values.

	  To compile this code as a module, choose M here: the
	  module will be called em_cmp.

config NET_EMATCH_NBYTE
	tristate "Multi byte comparison"
	depends on NET_EMATCH
	---help---
	  Say Y here if you want to be able to classify packets based on
	  multiple byte comparisons mainly useful for IPv6 address comparisons.

	  To compile this code as a module, choose M here: the
	  module will be called em_nbyte.

config NET_EMATCH_U32
	tristate "U32 key"
	depends on NET_EMATCH
	---help---
	  Say Y here if you want to be able to classify packets using
	  the famous u32 key in combination with logic relations.

	  To compile this code as a module, choose M here: the
	  module will be called em_u32.

config NET_EMATCH_META
	tristate "Metadata"
	depends on NET_EMATCH
	---help---
	  Say Y here if you want to be able to classify packets based on
	  metadata such as load average, netfilter attributes, socket
	  attributes and routing decisions.

	  To compile this code as a module, choose M here: the
	  module will be called em_meta.

config NET_EMATCH_TEXT
	tristate "Textsearch"
	depends on NET_EMATCH
	select TEXTSEARCH
	select TEXTSEARCH_KMP
	select TEXTSEARCH_BM
	select TEXTSEARCH_FSM
	---help---
	  Say Y here if you want to be able to classify packets based on
	  textsearch comparisons.

	  To compile this code as a module, choose M here: the
	  module will be called em_text.

config NET_EMATCH_CANID
	tristate "CAN Identifier"
	depends on NET_EMATCH && (CAN=y || CAN=m)
	---help---
	  Say Y here if you want to be able to classify CAN frames based
	  on CAN Identifier.

	  To compile this code as a module, choose M here: the
	  module will be called em_canid.

config NET_EMATCH_IPSET
	tristate "IPset"
	depends on NET_EMATCH && IP_SET
	---help---
	  Say Y here if you want to be able to classify packets based on
	  ipset membership.

	  To compile this code as a module, choose M here: the
	  module will be called em_ipset.

config NET_CLS_ACT
	bool "Actions"
	---help---
	  Say Y here if you want to use traffic control actions. Actions
	  get attached to classifiers and are invoked after a successful
	  classification. They are used to overwrite the classification
	  result, instantly drop or redirect packets, etc.

	  A recent version of the iproute2 package is required to use
	  extended matches.

config NET_ACT_POLICE
	tristate "Traffic Policing"
        depends on NET_CLS_ACT 
        ---help---
	  Say Y here if you want to do traffic policing, i.e. strict
	  bandwidth limiting. This action replaces the existing policing
	  module.

	  To compile this code as a module, choose M here: the
	  module will be called act_police.

config NET_ACT_GACT
        tristate "Generic actions"
        depends on NET_CLS_ACT
        ---help---
	  Say Y here to take generic actions such as dropping and
	  accepting packets.

	  To compile this code as a module, choose M here: the
	  module will be called act_gact.

config GACT_PROB
        bool "Probability support"
        depends on NET_ACT_GACT
        ---help---
	  Say Y here to use the generic action randomly or deterministically.

config NET_ACT_MIRRED
        tristate "Redirecting and Mirroring"
        depends on NET_CLS_ACT
        ---help---
	  Say Y here to allow packets to be mirrored or redirected to
	  other devices.

	  To compile this code as a module, choose M here: the
	  module will be called act_mirred.

config NET_ACT_IPT
        tristate "IPtables targets"
        depends on NET_CLS_ACT && NETFILTER && IP_NF_IPTABLES
        ---help---
	  Say Y here to be able to invoke iptables targets after successful
	  classification.

	  To compile this code as a module, choose M here: the
	  module will be called act_ipt.

config NET_ACT_NAT
        tristate "Stateless NAT"
        depends on NET_CLS_ACT
        ---help---
	  Say Y here to do stateless NAT on IPv4 packets.  You should use
	  netfilter for NAT unless you know what you are doing.

	  To compile this code as a module, choose M here: the
	  module will be called act_nat.

config NET_ACT_PEDIT
        tristate "Packet Editing"
        depends on NET_CLS_ACT
        ---help---
	  Say Y here if you want to mangle the content of packets.

	  To compile this code as a module, choose M here: the
	  module will be called act_pedit.

config NET_ACT_SIMP
        tristate "Simple Example (Debug)"
        depends on NET_CLS_ACT
        ---help---
	  Say Y here to add a simple action for demonstration purposes.
	  It is meant as an example and for debugging purposes. It will
	  print a configured policy string followed by the packet count
	  to the console for every packet that passes by.

	  If unsure, say N.

	  To compile this code as a module, choose M here: the
	  module will be called act_simple.

config NET_ACT_SKBEDIT
        tristate "SKB Editing"
        depends on NET_CLS_ACT
        ---help---
	  Say Y here to change skb priority or queue_mapping settings.

	  If unsure, say N.

	  To compile this code as a module, choose M here: the
	  module will be called act_skbedit.

config NET_ACT_CSUM
        tristate "Checksum Updating"
        depends on NET_CLS_ACT && INET
        ---help---
	  Say Y here to update some common checksum after some direct
	  packet alterations.

	  To compile this code as a module, choose M here: the
	  module will be called act_csum.

config NET_CLS_IND
	bool "Incoming device classification"
	depends on NET_CLS_U32 || NET_CLS_FW
	---help---
	  Say Y here to extend the u32 and fw classifier to support
	  classification based on the incoming device. This option is
	  likely to disappear in favour of the metadata ematch.

endif # NET_SCHED

config NET_SCH_FIFO
	bool