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2014-09-30net: sched: implement qstat helper routinesJohn Fastabend
This adds helpers to manipulate qstats logic and replaces locations that touch the counters directly. This simplifies future patches to push qstats onto per cpu counters. Signed-off-by: John Fastabend <john.r.fastabend@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-01pkt_sched: Stop using NLA_PUT*().David S. Miller
These macros contain a hidden goto, and are thus extremely error prone and make code hard to audit. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-05net_sched: red: split red_parms into parms and varsEric Dumazet
This patch splits the red_parms structure into two components. One holding the RED 'constant' parameters, and one containing the variables. This permits a size reduction of GRED qdisc, and is a preliminary step to add an optional RED unit to SFQ. SFQRED will have a single red_parms structure shared by all flows, and a private red_vars per flow. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Dave Taht <dave.taht@gmail.com> CC: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-09sch_red: generalize accurate MAX_P support to RED/GRED/CHOKEEric Dumazet
Now RED uses a Q0.32 number to store max_p (max probability), allow RED/GRED/CHOKE to use/report full resolution at config/dump time. Old tc binaries are non aware of new attributes, and still set/get Plog. New tc binary set/get both Plog and max_p for backward compatibility, they display "probability value" if they get max_p from new kernels. # tc -d qdisc show dev ... ... qdisc red 10: parent 1:1 limit 360Kb min 30Kb max 90Kb ecn ewma 5 probability 0.09 Scell_log 15 Make sure we avoid potential divides by 0 in reciprocal_value(), if (max_th - min_th) is big. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-08sch_red: Adaptative RED AQMEric Dumazet
Adaptative RED AQM for linux, based on paper from Sally FLoyd, Ramakrishna Gummadi, and Scott Shenker, August 2001 : http://icir.org/floyd/papers/adaptiveRed.pdf Goal of Adaptative RED is to make max_p a dynamic value between 1% and 50% to reach the target average queue : (max_th - min_th) / 2 Every 500 ms: if (avg > target and max_p <= 0.5) increase max_p : max_p += alpha; else if (avg < target and max_p >= 0.01) decrease max_p : max_p *= beta; target :[min_th + 0.4*(min_th - max_th), min_th + 0.6*(min_th - max_th)]. alpha : min(0.01, max_p / 4) beta : 0.9 max_P is a Q0.32 fixed point number (unsigned, with 32 bits mantissa) Changes against our RED implementation are : max_p is no longer a negative power of two (1/(2^Plog)), but a Q0.32 fixed point number, to allow full range described in Adatative paper. To deliver a random number, we now use a reciprocal divide (thats really a multiply), but this operation is done once per marked/droped packet when in RED_BETWEEN_TRESH window, so added cost (compared to previous AND operation) is near zero. dump operation gives current max_p value in a new TCA_RED_MAX_P attribute. Example on a 10Mbit link : tc qdisc add dev $DEV parent 1:1 handle 10: est 1sec 8sec red \ limit 400000 min 30000 max 90000 avpkt 1000 \ burst 55 ecn adaptative bandwidth 10Mbit # tc -s -d qdisc show dev eth3 ... qdisc red 10: parent 1:1 limit 400000b min 30000b max 90000b ecn adaptative ewma 5 max_p=0.113335 Scell_log 15 Sent 50414282 bytes 34504 pkt (dropped 35, overlimits 1392 requeues 0) rate 9749Kbit 831pps backlog 72056b 16p requeues 0 marked 1357 early 35 pdrop 0 other 0 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-01sch_red: fix red_changeEric Dumazet
Le mercredi 30 novembre 2011 à 14:36 -0800, Stephen Hemminger a écrit : > (Almost) nobody uses RED because they can't figure it out. > According to Wikipedia, VJ says that: > "there are not one, but two bugs in classic RED." RED is useful for high throughput routers, I doubt many linux machines act as such devices. I was considering adding Adaptative RED (Sally Floyd, Ramakrishna Gummadi, Scott Shender), August 2001 In this version, maxp is dynamic (from 1% to 50%), and user only have to setup min_th (target average queue size) (max_th and wq (burst in linux RED) are automatically setup) By the way it seems we have a small bug in red_change() if (skb_queue_empty(&sch->q)) red_end_of_idle_period(&q->parms); First, if queue is empty, we should call red_start_of_idle_period(&q->parms); Second, since we dont use anymore sch->q, but q->qdisc, the test is meaningless. Oh well... [PATCH] sch_red: fix red_change() Now RED is classful, we must check q->qdisc->q.qlen, and if queue is empty, we start an idle period, not end it. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-01-24Merge branch 'master' of ↵David S. Miller
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: net/sched/sch_hfsc.c net/sched/sch_htb.c net/sched/sch_tbf.c
2011-01-20net_sched: accurate bytes/packets stats/ratesEric Dumazet
In commit 44b8288308ac9d (net_sched: pfifo_head_drop problem), we fixed a problem with pfifo_head drops that incorrectly decreased sch->bstats.bytes and sch->bstats.packets Several qdiscs (CHOKe, SFQ, pfifo_head, ...) are able to drop a previously enqueued packet, and bstats cannot be changed, so bstats/rates are not accurate (over estimated) This patch changes the qdisc_bstats updates to be done at dequeue() time instead of enqueue() time. bstats counters no longer account for dropped frames, and rates are more correct, since enqueue() bursts dont have effect on dequeue() rate. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-01-19net_sched: cleanupsEric Dumazet
Cleanup net/sched code to current CodingStyle and practices. Reduce inline abuse Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-01-10net_sched: factorize qdisc stats handlingEric Dumazet
HTB takes into account skb is segmented in stats updates. Generalize this to all schedulers. They should use qdisc_bstats_update() helper instead of manipulating bstats.bytes and bstats.packets Add bstats_update() helper too for classes that use gnet_stats_basic_packed fields. Note : Right now, TCQ_F_CAN_BYPASS shortcurt can be taken only if no stab is setup on qdisc. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-01-03sch_red: report backlog informationEric Dumazet
Provide child qdisc backlog (byte count) information so that "tc -s qdisc" can report it to user. packet count is already correctly provided. qdisc red 11: parent 1:11 limit 60Kb min 15Kb max 45Kb ecn Sent 3116427684 bytes 1415782 pkt (dropped 8, overlimits 7866 requeues 0) rate 242385Kbit 13630pps backlog 13560b 8p requeues 0 marked 7865 early 1 pdrop 7 other 0 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-05-17net: Remove unnecessary returns from void function()sJoe Perches
This patch removes from net/ (but not any netfilter files) all the unnecessary return; statements that precede the last closing brace of void functions. It does not remove the returns that are immediately preceded by a label as gcc doesn't like that. Done via: $ grep -rP --include=*.[ch] -l "return;\n}" net/ | \ xargs perl -i -e 'local $/ ; while (<>) { s/\n[ \t\n]+return;\n}/\n}/g; print; }' Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-06net_sched: remove some unnecessary checks in classful schedulersPatrick McHardy
The class argument to the ->graft(), ->leaf(), ->dump(), ->dump_stats() all originate from either ->get() or ->walk() and are always valid. Remove unnecessary checks. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-06net_sched: make cls_ops->change and cls_ops->delete optionalPatrick McHardy
Some schedulers don't support creating, changing or deleting classes. Make the respective callbacks optionally and consistently return -EOPNOTSUPP for unsupported operations, instead of currently either -EOPNOTSUPP, -ENOSYS or no error. In case of sch_prio and sch_multiq, the removed operations additionally checked for an invalid class. This is not necessary since the class argument can only orginate from ->get() or in case of ->change is 0 for creation of new classes, in which case ->change() incorrectly returned -ENOENT. As a side-effect, this patch fixes a possible (root-only) NULL pointer function call in sch_ingress, which didn't implement a so far mandatory ->delete() operation. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-06net_sched: make cls_ops->tcf_chain() optionalPatrick McHardy
Some qdiscs don't support attaching filters. Handle this centrally in cls_api and return a proper errno code (EOPNOTSUPP) instead of EINVAL. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-20pkt_sched: remove unnecessary xchg() in packet schedulersPatrick McHardy
The use of xchg() hasn't been necessary since 2.2.something when proper locking was added to packet schedulers. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-13pkt_sched: Remove qdisc->ops->requeue() etc.Jarek Poplawski
After implementing qdisc->ops->peek() and changing sch_netem into classless qdisc there are no more qdisc->ops->requeue() users. This patch removes this method with its wrappers (qdisc_requeue()), and also unused qdisc->requeue structure. There are a few minor fixes of warnings (htb_enqueue()) and comments btw. The idea to kill ->requeue() and a similar patch were first developed by David S. Miller. Signed-off-by: Jarek Poplawski <jarkao2@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-31pkt_sched: Add qdisc->ops->peek() implementation.Jarek Poplawski
Add qdisc->ops->peek() implementation for work-conserving qdiscs. With feedback from Patrick McHardy. Signed-off-by: Jarek Poplawski <jarkao2@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-08-04net_sched: Add qdisc __NET_XMIT_STOLEN flagJarek Poplawski
Patrick McHardy <kaber@trash.net> noticed: "The other problem that affects all qdiscs supporting actions is TC_ACT_QUEUED/TC_ACT_STOLEN getting mapped to NET_XMIT_SUCCESS even though the packet is not queued, corrupting upper qdiscs' qlen counters." and later explained: "The reason why it translates it at all seems to be to not increase the drops counter. Within a single qdisc this could be avoided by other means easily, upper qdiscs would still increase the counter when we return anything besides NET_XMIT_SUCCESS though. This means we need a new NET_XMIT return value to indicate this to the upper qdiscs. So I'd suggest to introduce NET_XMIT_STOLEN, return that to upper qdiscs and translate it to NET_XMIT_SUCCESS in dev_queue_xmit, similar to NET_XMIT_BYPASS." David Miller <davem@davemloft.net> noticed: "Maybe these NET_XMIT_* values being passed around should be a set of bits. They could be composed of base meanings, combined with specific attributes. So you could say "NET_XMIT_DROP | __NET_XMIT_NO_DROP_COUNT" The attributes get masked out by the top-level ->enqueue() caller, such that the base meanings are the only thing that make their way up into the stack. If it's only about communication within the qdisc tree, let's simply code it that way." This patch is trying to realize these ideas. Signed-off-by: Jarek Poplawski <jarkao2@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-20net_sched: Add accessor function for packet length for qdiscsJussi Kivilinna
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-20net_sched: Add qdisc_enqueue wrapperJussi Kivilinna
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-05net-sched: consolidate default fifo qdisc setupPatrick McHardy
Signed-off-by: Patrick McHardy <kaber@trash.net> Acked-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-06-03netlink: Improve returned error codesThomas Graf
Make nlmsg_trim(), nlmsg_cancel(), genlmsg_cancel(), and nla_nest_cancel() void functions. Return -EMSGSIZE instead of -1 if the provided message buffer is not big enough. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[NET_SCHED]: Use nla_policy for attribute validation in packet schedulersPatrick McHardy
Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[NET_SCHED]: Propagate nla_parse return valuePatrick McHardy
nla_parse() returns more detailed errno codes, propagate them back on error. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[NET_SCHED]: Convert packet schedulers from rtnetlink to new netlink APIPatrick McHardy
Convert packet schedulers to use the netlink API. Unfortunately a gradual conversion is not possible without breaking compilation in the middle or adding lots of casts, so this patch converts them all in one step. The patch has been mostly generated automatically with some minor edits to at least allow seperate conversion of classifiers and actions. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[NET]: Move Qdisc_class_ops and Qdisc_ops in appropriate sections.Eric Dumazet
Qdisc_class_ops are const, and Qdisc_ops are mostly read. Using "const" and "__read_mostly" qualifiers helps to reduce false sharing. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10[NET_SCHED]: Remove unnecessary includesPatrick McHardy
Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-02-10[NET] SCHED: Fix whitespace errors.YOSHIFUJI Hideaki
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02[NET_SCHED]: Fix endless loops (part 2): "simple" qdiscsPatrick McHardy
Convert the "simple" qdiscs to use qdisc_tree_decrease_qlen() where necessary: - all graft operations - destruction of old child qdiscs in prio, red and tbf change operation - purging of queue in sfq change operation Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02[NET_SCHED]: Set parent classid in default qdiscsPatrick McHardy
Set parent classids in default qdiscs to allow walking up the tree from outside the qdiscs. This is needed by the next patch. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-30Remove obsolete #include <linux/config.h>Jörn Engel
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-03-20[PKT_SCHED]: Convert sch_red to a classful qdiscPatrick McHardy
Convert sch_red to a classful qdisc. All qdiscs that maintain accurate backlog counters are eligible as child qdiscs. When a queue limit larger than zero is given, a bfifo qdisc is used for backwards compatibility. Current versions of tc enforce a limit larger than zero, other users can avoid creating the default qdisc by using zero. Signed-off-by: Patrick McHardy <kaber@trash.net> Acked-by: Jamal Hadi Salim <hadi@cyberus.ca> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-11-05[PKT_SCHED]: (G)RED: Introduce hard droppingThomas Graf
Introduces a new flag TC_RED_HARDDROP which specifies that if ECN marking is enabled packets should still be dropped once the average queue length exceeds the maximum threshold. This _may_ help to avoid global synchronisation during small bursts of peers advertising but not caring about ECN. Use this option very carefully, it does more harm than good if (qth_max - qth_min) does not cover at least two average burst cycles. The difference to the current behaviour, in which we'd run into the hard queue limit, is that due to the low pass filter of RED short bursts are less likely to cause a global synchronisation. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2005-11-05[PKT_SCHED]: RED: Cleanup and remove unnecessary codeThomas Graf
Removes the skb trimming code which is not needed since we never touch the skb upon failure. Removes unnecessary includes, initializers, and simplifies the code a bit. Removes Jamal's obsolete email addresses upon his own request. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2005-11-05[PKT_SCHED]: RED: Dont start idle periods while already idlingThomas Graf
We should not interrupt and restart an idle period while idling already. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2005-11-05[PKT_SCHED]: RED: Use generic queue management interfaceThomas Graf
Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2005-11-05[PKT_SCHED]: RED: Use new generic red interfaceThomas Graf
Simplifies code a lot by separating the red algorithm and the queueing logic. We now differentiate between probability marks and forced marks but sum them together again to not break backwards compatibility. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2005-07-08[NET]: Transform skb_queue_len() binary tests into skb_queue_empty()David S. Miller
This is part of the grand scheme to eliminate the qlen member of skb_queue_head, and subsequently remove the 'list' member of sk_buff. Most users of skb_queue_len() want to know if the queue is empty or not, and that's trivially done with skb_queue_empty() which doesn't use the skb_queue_head->qlen member and instead uses the queue list emptyness as the test. Signed-off-by: David S. Miller <davem@davemloft.net>
2005-04-16Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
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