The PRIO qdisc supports flow control, such that packet
dequeue can be disabled based on boolean flag 'enable_flow'.
When flow is re-enabled, the latency for new packets
arriving at network driver is high. To reduce the delay in
scheduling packets, the qdisc will now invoke
__netif_schedule() to expedite dequeue. This significantly
reduces the latency of packets arriving at network driver.
Change-Id: Ic5fe3faf86f177300d3018b9f60974ba3811641c
CRs-Fixed: 355156
Acked-by: Jimi Shah <jimis@qualcomm.com>
Signed-off-by: Tianyi Gou <tgou@codeaurora.org>
Add enable_flow flag to the prio qdisc. Packet flow is
enabled by default, but can be disabled from userspace
(e.g. IPROUTE2 tc tool). This allows for suspending packet
dequeue on a per-qdisc basis, which is needed to supprot
Quality of Service (QOS) when using WWAN modem.
Change-Id: I932f296be946f1acc3b00c7d8569bbb733d33622
Acked-by: Andrew Richardson <randrew@qualcomm.com>
CRs-Fixed: 283471
Signed-off-by: Tianyi Gou <tgou@codeaurora.org>
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>
commit 07bd8df5df
(sch_sfq: fix peek() implementation) changed sfq to use generic
peek helper.
This makes HFSC complain about a non-work-conserving child qdisc, if
prio with sfq child is used within hfsc:
hfsc peeks into prio qdisc, which will then peek into sfq.
returned skb is stashed in sch->gso_skb.
Next, hfsc tries to dequeue from prio, but prio will call sfq dequeue
directly, which may return NULL instead of previously peeked-at skb.
Have prio call qdisc_dequeue_peeked, so sfq->dequeue() is
not called in this case.
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
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>
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>
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>
The first parameter dev isn't in use in qdisc_create_dflt().
Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Acked-by: Jamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>
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>
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Some classful qdiscs miss qstats.qlen updating with q.qlen of their
child qdiscs in dump_stats methods.
Signed-off-by: Jarek Poplawski <jarkao2@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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>
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>
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>
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>
From: Patrick McHardy <kaber@trash.net>
Just as a demonstration how easy adding a peek operation to the
work-conserving qdiscs actually is. It doesn't need to keep or change
any internal state in many cases thanks to the guarantee that the
packet will either be dequeued or, if another packet arrives, the
upper qdisc will immediately ->peek again to reevaluate the state.
(This is only slightly modified Patrick's patch.)
Signed-off-by: Jarek Poplawski <jarkao2@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Removes all _nested_compat() functions from the API. The prio qdisc
no longer requires them and netem has its own format anyway. Their
existance is only confusing.
Resend: Also remove the wrapper macro.
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use return value from inner qdisc requeue when value returned isn't
NET_XMIT_SUCCESS, instead of always returning NET_XMIT_DROP.
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
Patrick McHardy <kaber@trash.net> noticed that it would be nice to
handle NET_XMIT_BYPASS by NET_XMIT_SUCCESS with an internal qdisc flag
__NET_XMIT_BYPASS and to remove the mapping from dev_queue_xmit().
David Miller <davem@davemloft.net> spotted a serious bug in the first
version of this patch.
Signed-off-by: Jarek Poplawski <jarkao2@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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>
This actually fixes a bug added by the RR scheduler changes. The
->bands and ->prio2band parameters were being set outside of the
sch_tree_lock() and thus could result in strange behavior and
inconsistencies.
It might be possible, in the new design (where there will be one qdisc
per device TX queue) to allow similar functionality via a TX hash
algorithm for RR but I really see no reason to export this aspect of
how these multiqueue cards actually implement the scheduling of the
the individual DMA TX rings and the single physical MAC/PHY port.
Signed-off-by: David S. Miller <davem@davemloft.net>
It can be obtained via the netdev_queue. So create a helper routine,
qdisc_dev(), to make the transformations nicer looking.
Now, qdisc_alloc() now no longer needs a net_device pointer argument.
Signed-off-by: David S. Miller <davem@davemloft.net>
A netdev_queue is an entity managed by a qdisc.
Currently there is one RX and one TX queue, and a netdev_queue merely
contains a backpointer to the net_device.
The Qdisc struct is augmented with a netdev_queue pointer as well.
Eventually the 'dev' Qdisc member will go away and we will have the
resulting hierarchy:
net_device --> netdev_queue --> Qdisc
Also, qdisc_alloc() and qdisc_create_dflt() now take a netdev_queue
pointer argument.
Signed-off-by: David S. Miller <davem@davemloft.net>
Pass double tcf_proto pointers to tcf_destroy_chain() to make it
clear the start of the filter list for more consistency.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
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>
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>
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>
Fix one more user of netiff_subqueue_stopped. To check for the
queue id one must use the __netiff_subqueue_stoped call.
This run out of my sight when I made the:
668f895a85
[NET]: Hide the queue_mapping field inside netif_subqueue_stopped
commit :(
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
When CONFIG_NET_CLS_ACT is enabled, tc_classify() is called twice in
prio_classify(). This causes "interesting" behaviour: with the setup
below, packets are duplicated, sent twice to ifb0, and then loop in and
out of ifb0.
The patch uses the previously calculated return value in the switch,
which is probably what Patrick had in mind in commit
bdba91ec70 -- maybe Patrick can
double-check this?
-- example setup --
ifconfig ifb0 up
tc qdisc add dev ifb0 root netem delay 2s
tc qdisc add dev $ETH root handle 1: prio
tc filter add dev $ETH parent 1: protocol ip prio 10 u32 \
match ip dst 172.24.110.6/32 flowid 1:1 \
action mirred egress redirect dev ifb0
ping -c1 172.24.110.6
Signed-off-by: Lucas Nussbaum <lucas.nussbaum@imag.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix the check in prio_tune() to see if sch->parent is TC_H_ROOT instead of
sch->handle to load or reject the qdisc for multiqueue devices.
Signed-off-by: Peter P Waskiewicz Jr <peter.p.waskiewicz.jr@intel.com>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix handling of empty or completely non-matching filter chains. In
that case -1 is returned and tcf_result is uninitialized, the
qdisc should fall back to default classification in that case.
Noticed by PJ Waskiewicz <peter.p.waskiewicz.jr@intel.com>.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add the new sch_rr qdisc for multiqueue network device support. Allow
sch_prio and sch_rr to be compiled with or without multiqueue hardware
support.
sch_rr is part of sch_prio, and is referenced from MODULE_ALIAS. This
was done since sch_prio and sch_rr only differ in their dequeue
routine.
Signed-off-by: Peter P Waskiewicz Jr <peter.p.waskiewicz.jr@intel.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This fixes an out-of-boundary condition when the classified
band equals q->bands. Caught by Alexey
Signed-off-by: Jamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>
Spring cleaning time...
There seems to be a lot of places in the network code that have
extra bogus semicolons after conditionals. Most commonly is a
bogus semicolon after: switch() { }
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Uninline tcf_destroy and add a helper function to destroy an entire filter
chain.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
So that it is also an offset from skb->head, reduces its size from 8 to 4 bytes
on 64bit architectures, allowing us to combine the 4 bytes hole left by the
layer headers conversion, reducing struct sk_buff size to 256 bytes, i.e. 4
64byte cachelines, and since the sk_buff slab cache is SLAB_HWCACHE_ALIGN...
:-)
Many calculations that previously required that skb->{transport,network,
mac}_header be first converted to a pointer now can be done directly, being
meaningful as offsets or pointers.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
After Al Viro (finally) succeeded in removing the sched.h #include in module.h
recently, it makes sense again to remove other superfluous sched.h includes.
There are quite a lot of files which include it but don't actually need
anything defined in there. Presumably these includes were once needed for
macros that used to live in sched.h, but moved to other header files in the
course of cleaning it up.
To ease the pain, this time I did not fiddle with any header files and only
removed #includes from .c-files, which tend to cause less trouble.
Compile tested against 2.6.20-rc2 and 2.6.20-rc2-mm2 (with offsets) on alpha,
arm, i386, ia64, mips, powerpc, and x86_64 with allnoconfig, defconfig,
allmodconfig, and allyesconfig as well as a few randconfigs on x86_64 and all
configs in arch/arm/configs on arm. I also checked that no new warnings were
introduced by the patch (actually, some warnings are removed that were emitted
by unnecessarily included header files).
Signed-off-by: Tim Schmielau <tim@physik3.uni-rostock.de>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch adds a dump_stats callback to enable
printing of basic statistics of prio classes.
(With help of Patrick McHardy).
Signed-off-by: Jarek Poplawski <jarkao2@o2.pl>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
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>
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>
The drop operation is optional and qdiscs must check if childs support it.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently when PRIO is configured to use N bands, it lets the packets be
directed to any of the bands 0..N-1. However, PRIO attaches a fifo qdisc
only to the bands that appear in the priomap; the rest of the N bands
remain with a noop qdisc attached. This patch changes PRIO's behavior so
that it attaches a fifo qdisc to all of the N bands.
Signed-off-by: Amnon Aaronsohn <bla@cs.huji.ac.il>
Signed-off-by: David S. Miller <davem@davemloft.net>
Tianyi Gou
David S. Miller
Florian Westphal
Eric Dumazet
Changli Gao
Joe Perches
Tejun Heo
Jarek Poplawski
Patrick McHardy
Thomas Graf
Jussi Kivilinna
Eric Dumazet
Pavel Emelyanov
Lucas Nussbaum
Peter P Waskiewicz Jr
Jamal Hadi Salim
Stephen Hemminger
Arnaldo Carvalho de Melo
Tim Schmielau
YOSHIFUJI Hideaki
Jarek Poplawski
Jörn Engel
Amnon Aaronsohn