26 Jun, 2016
1 commit
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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
Acked-by: Jesper Dangaard Brouer
Signed-off-by: David S. Miller
11 Jun, 2016
2 commits
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__QDISC_STATE_THROTTLED bit manipulation is rather expensive
for HTB and few others.I already removed it for sch_fq in commit f2600cf02b5b
("net: sched: avoid costly atomic operation in fq_dequeue()")
and so far nobody complained.When one ore more packets are stuck in one or more throttled
HTB class, a htb dequeue() performs two atomic operations
to clear/set __QDISC_STATE_THROTTLED bit, while root qdisc
lock is held.Removing this pair of atomic operations bring me a 8 % performance
increase on 200 TCP_RR tests, in presence of throttled classes.This patch has no side effect, since nothing actually uses
disc_is_throttled() anymore.Signed-off-by: Eric Dumazet
Signed-off-by: David S. Miller -
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.cIn 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
09 Jun, 2016
2 commits
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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
Signed-off-by: David S. Miller -
After the removal of TCA_CBQ_POLICE in cbq scheduler qdisc->reshape_fail
is always NULL, i.e. qdisc_rehape_fail is now the same as qdisc_drop.Signed-off-by: Florian Westphal
Signed-off-by: David S. Miller
04 Jun, 2016
1 commit
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Fixes: 2ccccf5fb43f ("net_sched: update hierarchical backlog too")
Cc: Jamal Hadi Salim
Signed-off-by: Cong Wang
Signed-off-by: David S. Miller
26 Apr, 2016
1 commit
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Signed-off-by: Nicolas Dichtel
Signed-off-by: David S. Miller
01 Mar, 2016
2 commits
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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
Acked-by: Jamal Hadi Salim
Signed-off-by: Cong Wang
Signed-off-by: David S. Miller -
Remove nearly duplicated code and prepare for the following patch.
Cc: Jamal Hadi Salim
Acked-by: Jamal Hadi Salim
Signed-off-by: Cong Wang
Signed-off-by: David S. Miller
06 Oct, 2014
1 commit
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Standard qdisc API to setup a timer implies an atomic operation on every
packet dequeue : qdisc_unthrottled()It turns out this is not really needed for FQ, as FQ has no concept of
global qdisc throttling, being a qdisc handling many different flows,
some of them can be throttled, while others are not.Fix is straightforward : add a 'bool throttle' to
qdisc_watchdog_schedule_ns(), and remove calls to qdisc_unthrottled()
in sch_fq.Signed-off-by: Eric Dumazet
Signed-off-by: David S. Miller
30 Sep, 2014
1 commit
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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
Signed-off-by: David S. Miller
23 Aug, 2014
1 commit
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ktime_get_ns() replaces ktime_to_ns(ktime_get())
ktime_get_real_ns() replaces ktime_to_ns(ktime_get_real())
Signed-off-by: Eric Dumazet
Signed-off-by: David S. Miller
14 Mar, 2014
1 commit
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nla_nest_end() already has return skb->len, so replace
return skb->len with return nla_nest_end instead().Signed-off-by: Yang Yingliang
Signed-off-by: David S. Miller
06 Mar, 2014
1 commit
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Conflicts:
drivers/net/wireless/ath/ath9k/recv.c
drivers/net/wireless/mwifiex/pcie.c
net/ipv6/sit.cThe SIT driver conflict consists of a bug fix being done by hand
in 'net' (missing u64_stats_init()) whilst in 'net-next' a helper
was created (netdev_alloc_pcpu_stats()) which takes care of this.The two wireless conflicts were overlapping changes.
Signed-off-by: David S. Miller
04 Mar, 2014
1 commit
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On x86_64 we have 3 holes in struct tbf_sched_data.
The member peak_present can be replaced with peak.rate_bytes_ps,
because peak.rate_bytes_ps is set only when peak is specified in
tbf_change(). tbf_peak_present() is introduced to test
peak.rate_bytes_ps.The member max_size is moved to fill 32bit hole.
Signed-off-by: Hiroaki SHIMODA
Signed-off-by: David S. Miller
28 Feb, 2014
1 commit
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The allocated child qdisc is not freed in error conditions.
Defer the allocation after user configuration turns out to be
valid and acceptable.Fixes: cc106e441a63b ("net: sched: tbf: fix the calculation of max_size")
Signed-off-by: Hiroaki SHIMODA
Cc: Yang Yingliang
Acked-by: Eric Dumazet
Signed-off-by: David S. Miller
27 Jan, 2014
1 commit
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This moves part of Eric Dumazets skb_gso_seglen helper from tbf sched to
skbuff core so it may be reused by upcoming ip forwarding path patch.Signed-off-by: Florian Westphal
Acked-by: Eric Dumazet
Signed-off-by: David S. Miller
27 Dec, 2013
1 commit
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When we set burst to 1514 with low rate in userspace,
the kernel get a value of burst that less than 1514,
which doesn't work.Because it may make some loss when transform burst
to buffer in userspace. This makes burst lose some
bytes, when the kernel transform the buffer back to
burst.This patch adds two new attributes to support sending
burst/mtu to kernel directly to avoid the loss.Signed-off-by: Yang Yingliang
Acked-by: Eric Dumazet
Signed-off-by: David S. Miller
12 Dec, 2013
2 commits
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It's doing a 64-bit divide which is not supported
on 32-bit architectures in psched_ns_t2l(). The
correct way to do this is to use do_div().It's introduced by commit cc106e441a63
("net: sched: tbf: fix the calculation of max_size")Reported-by: kbuild test robot
Signed-off-by: Yang Yingliang
Signed-off-by: David S. Miller -
Current max_size is caluated from rate table. Now, the rate table
has been replaced and it's wrong to caculate max_size based on this
rate table. It can lead wrong calculation of max_size.The burst in kernel may be lower than user asked, because burst may gets
some loss when transform it to buffer(E.g. "burst 40kb rate 30mbit/s")
and it seems we cannot avoid this loss. Burst's value(max_size) based on
rate table may be equal user asked. If a packet's length is max_size, this
packet will be stalled in tbf_dequeue() because its length is above the
burst in kernel so that it cannot get enough tokens. The max_size guards
against enqueuing packet sizes above q->buffer "time" in tbf_enqueue().To make consistent with the calculation of tokens, this patch add a helper
psched_ns_t2l() to calculate burst(max_size) directly to fix this problem.After this fix, we can support to using 64bit rates to calculate burst as well.
Signed-off-by: Yang Yingliang
Acked-by: Eric Dumazet
Signed-off-by: David S. Miller
24 Nov, 2013
1 commit
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If a too small burst is inadvertently set on TBF, we might trigger
a bug in tbf_segment(), as 'skb' instead of 'segs' was used in a
qdisc_reshape_fail() call.tc qdisc add dev eth0 root handle 1: tbf latency 50ms burst 1KB rate
50mbitFix the bug, and add a warning, as such configuration is not
going to work anyway for non GSO packets.(For some reason, one has to use a burst >= 1520 to get a working
configuration, even with old kernels. This is a probable iproute2/tc
bug)Based on a report and initial patch from Yang Yingliang
Fixes: e43ac79a4bc6 ("sch_tbf: segment too big GSO packets")
Signed-off-by: Eric Dumazet
Reported-by: Yang Yingliang
Signed-off-by: David S. Miller
10 Nov, 2013
1 commit
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With psched_ratecfg_precompute(), tbf can deal with 64bit rates.
Add two new attributes so that tc can use them to break the 32bit
limit.Signed-off-by: Yang Yingliang
Suggested-by: Sergei Shtylyov
Acked-by: Eric Dumazet
Signed-off-by: David S. Miller
21 Sep, 2013
1 commit
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Add an extra u64 rate parameter to psched_ratecfg_precompute()
so that some qdisc can opt-in for 64bit rates in the future,
to overcome the ~34 Gbits limit.psched_ratecfg_getrate() reports a legacy structure to
tc utility, so if actual rate is above the 32bit rate field,
cap it to the 34Gbit limit.Signed-off-by: Eric Dumazet
Signed-off-by: David S. Miller
06 Jun, 2013
1 commit
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Merge 'net' bug fixes into 'net-next' as we have patches
that will build on top of them.This merge commit includes a change from Emil Goode
(emilgoode@gmail.com) that fixes a warning that would
have been introduced by this merge. Specifically it
fixes the pingv6_ops method ipv6_chk_addr() to add a
"const" to the "struct net_device *dev" argument and
likewise update the dummy_ipv6_chk_addr() declaration.Signed-off-by: David S. Miller
03 Jun, 2013
1 commit
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commit 56b765b79 ("htb: improved accuracy at high rates")
broke the "overhead xxx" handling, as well as the "linklayer atm"
attribute.tc class add ... htb rate X ceil Y linklayer atm overhead 10
This patch restores the "overhead xxx" handling, for htb, tbf
and act_policeThe "linklayer atm" thing needs a separate fix.
Reported-by: Jesper Dangaard Brouer
Signed-off-by: Eric Dumazet
Cc: Vimalkumar
Cc: Jiri Pirko
Signed-off-by: David S. Miller
23 May, 2013
1 commit
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If a GSO packet has a length above tbf burst limit, the packet
is currently silently dropped.Current way to handle this is to set the device in non GSO/TSO mode, or
setting high bursts, and its sub optimal.We can actually segment too big GSO packets, and send individual
segments as tbf parameters allow, allowing for better interoperability.Signed-off-by: Eric Dumazet
Cc: Ben Hutchings
Cc: Jiri Pirko
Cc: Jamal Hadi Salim
Reviewed-by: Jiri Pirko
Signed-off-by: David S. Miller
13 Feb, 2013
1 commit
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Current TBF uses rate table computed by the "tc" userspace program,
which has the following issue:The rate table has 256 entries to map packet lengths to
token (time units). With TSO sized packets, the 256 entry granularity
leads to loss/gain of rate, making the token bucket inaccurate.Thus, instead of relying on rate table, this patch explicitly computes
the time and accounts for packet transmission times with nanosecond
granularity.This is a followup to 56b765b79e9a78dc7d3f8850ba5e5567205a3ecd
("htb: improved accuracy at high rates").Signed-off-by: Jiri Pirko
Acked-by: Eric Dumazet
Signed-off-by: David S. Miller
02 Apr, 2012
1 commit
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These macros contain a hidden goto, and are thus extremely error
prone and make code hard to audit.Signed-off-by: David S. Miller
30 Dec, 2011
1 commit
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Provide child qdisc backlog (byte count) information so that "tc -s
qdisc" can report it to user.qdisc netem 30: root refcnt 18 limit 1000 delay 20.0ms 10.0ms
Sent 948517 bytes 898 pkt (dropped 0, overlimits 0 requeues 1)
rate 175056bit 16pps backlog 114b 1p requeues 1
qdisc tbf 40: parent 30: rate 256000bit burst 20Kb/8 mpu 0b lat 0us
Sent 948517 bytes 898 pkt (dropped 15, overlimits 611 requeues 0)
backlog 18168b 12p requeues 0Signed-off-by: Eric Dumazet
Signed-off-by: David S. Miller
25 Jan, 2011
1 commit
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Conflicts:
net/sched/sch_hfsc.c
net/sched/sch_htb.c
net/sched/sch_tbf.c
21 Jan, 2011
2 commits
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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.packetsSeveral 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
Acked-by: Stephen Hemminger
Signed-off-by: David S. Miller -
In commit 371121057607e (net: QDISC_STATE_RUNNING dont need atomic bit
ops) I moved QDISC_STATE_RUNNING flag to __state container, located in
the cache line containing qdisc lock and often dirtied fields.I now move TCQ_F_THROTTLED bit too, so that we let first cache line read
mostly, and shared by all cpus. This should speedup HTB/CBQ for example.Not using test_bit()/__clear_bit()/__test_and_set_bit allows to use an
"unsigned int" for __state container, reducing by 8 bytes Qdisc size.Introduce helpers to hide implementation details.
Signed-off-by: Eric Dumazet
CC: Patrick McHardy
CC: Jesper Dangaard Brouer
CC: Jarek Poplawski
CC: Jamal Hadi Salim
CC: Stephen Hemminger
Signed-off-by: David S. Miller
20 Jan, 2011
1 commit
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Cleanup net/sched code to current CodingStyle and practices.
Reduce inline abuse
Signed-off-by: Eric Dumazet
Signed-off-by: David S. Miller
11 Jan, 2011
1 commit
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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.packetsAdd 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
Signed-off-by: David S. Miller
10 Aug, 2010
1 commit
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This is based on work originally done by Patric McHardy.
Signed-off-by: Ben Greear
Signed-off-by: David S. Miller
18 May, 2010
1 commit
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Several netem users use TBF for rate control. But every time the parameters
of TBF are changed it destroys the child qdisc, requiring reconfigation.
Better to just keep child qdisc and just notify it of changed limit.Signed-off-by: Stephen Hemminger
Signed-off-by: David S. Miller
06 Sep, 2009
3 commits
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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
Signed-off-by: David S. Miller -
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
Signed-off-by: David S. Miller -
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
Signed-off-by: David S. Miller
22 Mar, 2009
1 commit
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tcp_sack_swap seems unnecessary so I pushed swap to the caller.
Also removed comment that seemed then pointless, and added include
when not already there. Compile tested.Signed-off-by: Ilpo Järvinen
Signed-off-by: David S. Miller
