Commit Graph

61 Commits

Author SHA1 Message Date
Jakub Kicinski 416ef9b15c net: sched: red: don't reset the backlog on every stat dump
Commit 0dfb33a0d7 ("sch_red: report backlog information") copied
child's backlog into RED's backlog.  Back then RED did not maintain
its own backlog counts.  This has changed after commit 2ccccf5fb4
("net_sched: update hierarchical backlog too") and commit d7f4f332f0
("sch_red: update backlog as well").  Copying is no longer necessary.

Tested:

$ tc -s qdisc show dev veth0
qdisc red 1: root refcnt 2 limit 400000b min 30000b max 30000b ecn
 Sent 20942 bytes 221 pkt (dropped 0, overlimits 0 requeues 0)
 backlog 1260b 14p requeues 14
  marked 0 early 0 pdrop 0 other 0
qdisc tbf 2: parent 1: rate 1Kbit burst 15000b lat 3585.0s
 Sent 20942 bytes 221 pkt (dropped 0, overlimits 138 requeues 0)
 backlog 1260b 14p requeues 14

Recently RED offload was added.  We need to make sure drivers don't
depend on resetting the stats.  This means backlog should be treated
like any other statistic:

  total_stat = new_hw_stat - prev_hw_stat;

Adjust mlxsw.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Nogah Frankel <nogahf@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-17 14:29:32 -05:00
Nogah Frankel f8253df553 net: sch: red: Change offloaded xstats to be incremental
Change the value of the xstats requested from the driver for offloaded RED
to be incremental, like the normal stats.
It increases consistency - if a qdisc stops being offloaded its xstats
don't change.

Signed-off-by: Nogah Frankel <nogahf@mellanox.com>
Reviewed-by: Yuval Mintz <yuvalm@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-10 16:07:40 -05:00
Nogah Frankel 8234af2db3 net_sch: red: Fix the new offload indication
Update the offload flag, TCQ_F_OFFLOADED, in each dump call (and ignore
the offloading function return value in relation to this flag).
This is done because a qdisc is being initialized, and therefore offloaded
before being grafted. Since the ability of the driver to offload the qdisc
depends on its location, a qdisc can be offloaded and un-offloaded by graft
calls, that doesn't effect the qdisc itself.

Fixes: 428a68af3a ("net: sched: Move to new offload indication in RED"
Signed-off-by: Nogah Frankel <nogahf@mellanox.com>
Reviewed-by: Yuval Mintz <yuvalm@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-02 13:17:45 -05:00
Alexander Aring a38a98821c net: sch: api: add extack support in qdisc_create_dflt
This patch adds extack support for the function qdisc_create_dflt which is
a common used function in the tc subsystem. Callers which are interested
in the receiving error can assign extack to get a more detailed
information why qdisc_create_dflt failed. The function qdisc_create_dflt
will also call an init callback which can fail by any per-qdisc specific
handling.

Cc: David Ahern <dsahern@gmail.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Alexander Aring <aring@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-21 12:32:51 -05:00
Alexander Aring 653d6fd68d net: sched: sch: add extack for graft callback
This patch adds extack support for graft callback to prepare per-qdisc
specific changes for extack.

Cc: David Ahern <dsahern@gmail.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Alexander Aring <aring@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-21 12:32:50 -05:00
Alexander Aring 2030721cc0 net: sched: sch: add extack for change qdisc ops
This patch adds extack support for change callback for qdisc ops
structtur to prepare per-qdisc specific changes for extack.

Cc: David Ahern <dsahern@gmail.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Alexander Aring <aring@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-21 12:32:50 -05:00
Alexander Aring e63d7dfd2d net: sched: sch: add extack for init callback
This patch adds extack support for init callback to prepare per-qdisc
specific changes for extack.

Cc: David Ahern <dsahern@gmail.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Alexander Aring <aring@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-21 12:32:50 -05:00
Yuval Mintz 428a68af3a net: sched: Move to new offload indication in RED
Let RED utilize the new internal flag, TCQ_F_OFFLOADED,
to mark a given qdisc as offloaded instead of using a dedicated
indication.

Also, change internal logic into looking at said flag when possible.

Fixes: 602f3baf22 ("net_sch: red: Add offload ability to RED qdisc")
Signed-off-by: Yuval Mintz <yuvalm@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-15 13:35:36 -05:00
Nogah Frankel 8afa10cbe2 net_sched: red: Avoid illegal values
Check the qmin & qmax values doesn't overflow for the given Wlog value.
Check that qmin <= qmax.

Fixes: a783474591 ("[PKT_SCHED]: Generic RED layer")
Signed-off-by: Nogah Frankel <nogahf@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-05 14:37:13 -05:00
Andrew Morton ee9d3429c0 net/sched/sch_red.c: work around gcc-4.4.4 anon union initializer issue
gcc-4.4.4 (at lest) has issues with initializers and anonymous unions:

net/sched/sch_red.c: In function 'red_dump_offload':
net/sched/sch_red.c:282: error: unknown field 'stats' specified in initializer
net/sched/sch_red.c:282: warning: initialization makes integer from pointer without a cast
net/sched/sch_red.c:283: error: unknown field 'stats' specified in initializer
net/sched/sch_red.c:283: warning: initialization makes integer from pointer without a cast
net/sched/sch_red.c: In function 'red_dump_stats':
net/sched/sch_red.c:352: error: unknown field 'xstats' specified in initializer
net/sched/sch_red.c:352: warning: initialization makes integer from pointer without a cast

Work around this.

Fixes: 602f3baf22 ("net_sch: red: Add offload ability to RED qdisc")
Cc: Nogah Frankel <nogahf@mellanox.com>
Cc: Jiri Pirko <jiri@mellanox.com>
Cc: Simon Horman <simon.horman@netronome.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-13 10:33:07 +09:00
Nogah Frankel 602f3baf22 net_sch: red: Add offload ability to RED qdisc
Add the ability to offload RED qdisc by using ndo_setup_tc.
There are four commands for RED offloading:
* TC_RED_SET: handles set and change.
* TC_RED_DESTROY: handle qdisc destroy.
* TC_RED_STATS: update the qdiscs counters (given as reference)
* TC_RED_XSTAT: returns red xstats.

Whether RED is being offloaded is being determined every time dump action
is being called because parent change of this qdisc could change its
offload state but doesn't require any RED function to be called.

Signed-off-by: Nogah Frankel <nogahf@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-08 12:23:37 +09:00
Kees Cook cdeabbb881 net: sched: Convert timers to use timer_setup()
In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly. Add pointer back to Qdisc.

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: netdev@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-18 12:39:54 +01:00
WANG Cong 143976ce99 net_sched: remove tc class reference counting
For TC classes, their ->get() and ->put() are always paired, and the
reference counting is completely useless, because:

1) For class modification and dumping paths, we already hold RTNL lock,
   so all of these ->get(),->change(),->put() are atomic.

2) For filter bindiing/unbinding, we use other reference counter than
   this one, and they should have RTNL lock too.

3) For ->qlen_notify(), it is special because it is called on ->enqueue()
   path, but we already hold qdisc tree lock there, and we hold this
   tree lock when graft or delete the class too, so it should not be gone
   or changed until we release the tree lock.

Therefore, this patch removes ->get() and ->put(), but:

1) Adds a new ->find() to find the pointer to a class by classid, no
   refcnt.

2) Move the original class destroy upon the last refcnt into ->delete(),
   right after releasing tree lock. This is fine because the class is
   already removed from hash when holding the lock.

For those who also use ->put() as ->unbind(), just rename them to reflect
this change.

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-25 17:19:10 -07:00
Johannes Berg fceb6435e8 netlink: pass extended ACK struct to parsing functions
Pass the new extended ACK reporting struct to all of the generic
netlink parsing functions. For now, pass NULL in almost all callers
(except for some in the core.)

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-13 13:58:22 -04:00
Jiri Kosina 49b499718f net: sched: make default fifo qdiscs appear in the dump
The original reason [1] for having hidden qdiscs (potential scalability
issues in qdisc_match_from_root() with single linked list in case of large
amount of qdiscs) has been invalidated by 59cc1f61f0 ("net: sched: convert
qdisc linked list to hashtable").

This allows us for bringing more clarity and determinism into the dump by
making default pfifo qdiscs visible.

We're not turning this on by default though, at it was deemed [2] too
intrusive / unnecessary change of default behavior towards userspace.
Instead, TCA_DUMP_INVISIBLE netlink attribute is introduced, which allows
applications to request complete qdisc hierarchy dump, including the
ones that have always been implicit/invisible.

Singleton noop_qdisc stays invisible, as teaching the whole infrastructure
about singletons would require quite some surgery with very little gain
(seeing no qdisc or seeing noop qdisc in the dump is probably setting
the same user expectation).

[1] http://lkml.kernel.org/r/1460732328.10638.74.camel@edumazet-glaptop3.roam.corp.google.com
[2] http://lkml.kernel.org/r/20161021.105935.1907696543877061916.davem@davemloft.net

Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-12 22:53:02 -07:00
Eric Dumazet 520ac30f45 net_sched: drop packets after root qdisc lock is released
Qdisc performance suffers when packets are dropped at enqueue()
time because drops (kfree_skb()) are done while qdisc lock is held,
delaying a dequeue() draining the queue.

Nominal throughput can be reduced by 50 % when this happens,
at a time we would like the dequeue() to proceed as fast as possible.

Even FQ is vulnerable to this problem, while one of FQ goals was
to provide some flow isolation.

This patch adds a 'struct sk_buff **to_free' parameter to all
qdisc->enqueue(), and in qdisc_drop() helper.

I measured a performance increase of up to 12 %, but this patch
is a prereq so that future batches in enqueue() can fly.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-25 12:19:35 -04:00
David S. Miller 1578b0a5e9 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	net/sched/act_police.c
	net/sched/sch_drr.c
	net/sched/sch_hfsc.c
	net/sched/sch_prio.c
	net/sched/sch_red.c
	net/sched/sch_tbf.c

In net-next the drop methods of the packet schedulers got removed, so
the bug fixes to them in 'net' are irrelevant.

A packet action unload crash fix conflicts with the addition of the
new firstuse timestamp.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-10 11:52:24 -07:00
Florian Westphal a09ceb0e08 sched: remove qdisc->drop
after removal of TCA_CBQ_OVL_STRATEGY from cbq scheduler, there are no
more callers of ->drop() outside of other ->drop functions, i.e.
nothing calls them.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-08 23:58:52 -07:00
WANG Cong d7f4f332f0 sch_red: update backlog as well
Fixes: 2ccccf5fb4 ("net_sched: update hierarchical backlog too")
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-03 19:24:04 -04:00
WANG Cong 2ccccf5fb4 net_sched: update hierarchical backlog too
When the bottom qdisc decides to, for example, drop some packet,
it calls qdisc_tree_decrease_qlen() to update the queue length
for all its ancestors, we need to update the backlog too to
keep the stats on root qdisc accurate.

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-29 17:02:33 -05:00
WANG Cong 86a7996cc8 net_sched: introduce qdisc_replace() helper
Remove nearly duplicated code and prepare for the following patch.

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-29 17:02:33 -05:00
John Fastabend 25331d6ce4 net: sched: implement qstat helper routines
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>
2014-09-30 01:02:26 -04:00
David S. Miller 1b34ec43c9 pkt_sched: Stop using NLA_PUT*().
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>
2012-04-01 18:11:37 -04:00
Eric Dumazet eeca6688d6 net_sched: red: split red_parms into parms and vars
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>
2012-01-05 14:01:21 -05:00
Eric Dumazet a73ed26bba sch_red: generalize accurate MAX_P support to RED/GRED/CHOKE
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>
2011-12-09 13:46:15 -05:00
Eric Dumazet 8af2a218de sch_red: Adaptative RED AQM
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>
2011-12-08 19:52:43 -05:00
Eric Dumazet 1ee5fa1e99 sch_red: fix red_change
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>
2011-12-01 19:24:38 -05:00
David S. Miller 5bdc22a565 Merge branch 'master' of 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
2011-01-24 14:09:35 -08:00
Eric Dumazet 9190b3b320 net_sched: accurate bytes/packets stats/rates
In commit 44b8288308 (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>
2011-01-20 23:31:33 -08:00
Eric Dumazet cc7ec456f8 net_sched: cleanups
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>
2011-01-19 23:31:12 -08:00
Eric Dumazet bfe0d0298f net_sched: factorize qdisc stats handling
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>
2011-01-10 16:07:54 -08:00
Eric Dumazet 0dfb33a0d7 sch_red: report backlog information
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>
2011-01-03 12:13:15 -08:00
Joe Perches 3fa21e07e6 net: Remove unnecessary returns from void function()s
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>
2010-05-17 23:23:14 -07:00
Patrick McHardy 5b9a9ccfad net_sched: remove some unnecessary checks in classful schedulers
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>
2009-09-06 02:07:02 -07:00
Patrick McHardy de6d5cdf88 net_sched: make cls_ops->change and cls_ops->delete optional
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>
2009-09-06 02:07:02 -07:00
Patrick McHardy 71ebe5e919 net_sched: make cls_ops->tcf_chain() optional
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>
2009-09-06 02:06:12 -07:00
Patrick McHardy b94c8afcba pkt_sched: remove unnecessary xchg() in packet schedulers
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>
2008-11-20 04:11:36 -08:00
Jarek Poplawski f30ab418a1 pkt_sched: Remove qdisc->ops->requeue() etc.
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>
2008-11-13 22:56:30 -08:00
Jarek Poplawski 8e3af97899 pkt_sched: Add qdisc->ops->peek() implementation.
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>
2008-10-31 00:45:55 -07:00
Jarek Poplawski 378a2f090f net_sched: Add qdisc __NET_XMIT_STOLEN flag
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>
2008-08-04 22:31:03 -07:00
Jussi Kivilinna 0abf77e55a net_sched: Add accessor function for packet length for qdiscs
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-20 00:08:27 -07:00
Jussi Kivilinna 5f86173bdf net_sched: Add qdisc_enqueue wrapper
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-20 00:08:04 -07:00
Patrick McHardy fb0305ce1b net-sched: consolidate default fifo qdisc setup
Signed-off-by: Patrick McHardy <kaber@trash.net>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-05 23:40:21 -07:00
Thomas Graf bc3ed28caa netlink: Improve returned error codes
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>
2008-06-03 16:36:54 -07:00
Patrick McHardy 27a3421e48 [NET_SCHED]: Use nla_policy for attribute validation in packet schedulers
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 15:11:22 -08:00
Patrick McHardy cee63723b3 [NET_SCHED]: Propagate nla_parse return value
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 15:11:18 -08:00
Patrick McHardy 1e90474c37 [NET_SCHED]: Convert packet schedulers from rtnetlink to new netlink API
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 15:11:10 -08:00
Eric Dumazet 20fea08b5f [NET]: Move Qdisc_class_ops and Qdisc_ops in appropriate sections.
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>
2008-01-28 14:53:58 -08:00
Patrick McHardy 0ba4805383 [NET_SCHED]: Remove unnecessary includes
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:16:41 -07:00
YOSHIFUJI Hideaki 10297b9931 [NET] SCHED: Fix whitespace errors.
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-02-10 23:20:08 -08:00