Commit Graph

288 Commits

Author SHA1 Message Date
Patrick McHardy 3c0cfc1358 [NET_SCHED]: Show timer resolution instead of clock resolution in /proc/net/psched
The fourth parameter of /proc/net/psched is supposed to show the timer
resultion and is used by HTB userspace to calculate the necessary
burst rate. Currently we show the clock resolution, which results in a
too low burst rate when the two differ.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:55:59 -07:00
Stephen Hemminger cfcabdcc2d [NET]: sparse warning fixes
Fix a bunch of sparse warnings. Mostly about 0 used as
NULL pointer, and shadowed variable declarations.
One notable case was that hash size should have been unsigned.

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:54:48 -07:00
Herbert Xu b421995235 [PKT_SCHED]: Add stateless NAT
Stateless NAT is useful in controlled environments where restrictions are
placed on through traffic such that we don't need connection tracking to
correctly NAT protocol-specific data.

In particular, this is of interest when the number of flows or the number
of addresses being NATed is large, or if connection tracking information
has to be replicated and where it is not practical to do so.

Previously we had stateless NAT functionality which was integrated into
the IPv4 routing subsystem.  This was a great solution as long as the NAT
worked on a subnet to subnet basis such that the number of NAT rules was
relatively small.  The reason is that for SNAT the routing based system
had to perform a linear scan through the rules.

If the number of rules is large then major renovations would have take
place in the routing subsystem to make this practical.

For the time being, the least intrusive way of achieving this is to use
the u32 classifier written by Alexey Kuznetsov along with the actions
infrastructure implemented by Jamal Hadi Salim.

The following patch is an attempt at this problem by creating a new nat
action that can be invoked from u32 hash tables which would allow large
number of stateless NAT rules that can be used/updated in constant time.

The actual NAT code is mostly based on the previous stateless NAT code
written by Alexey.  In future we might be able to utilise the protocol
NAT code from netfilter to improve support for other protocols.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:53:11 -07:00
Stephen Hemminger 3b04ddde02 [NET]: Move hardware header operations out of netdevice.
Since hardware header operations are part of the protocol class
not the device instance, make them into a separate object and
save memory.

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:52:52 -07:00
Stephen Hemminger 0c4e85813d [NET]: Wrap netdevice hardware header creation.
Add inline for common usage of hardware header creation, and
fix bug in IPV6 mcast where the assumption about negative return is
an errno. Negative return from hard_header means not enough space
was available,(ie -N bytes).

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:52:50 -07:00
Jamal Hadi Salim 8236632fb3 [NET_SCHED]: explict hold dev tx lock
For N cpus, with full throttle traffic on all N CPUs, funneling traffic
to the same ethernet device, the devices queue lock is contended by all
N CPUs constantly. The TX lock is only contended by a max of 2 CPUS.
In the current mode of operation, after all the work of entering the
dequeue region, we may endup aborting the path if we are unable to get
the tx lock and go back to contend for the queue lock. As N goes up,
this gets worse.

The changes in this patch result in a small increase in performance
with a 4CPU (2xdual-core) with no irq binding. Both e1000 and tg3
showed similar behavior;

Signed-off-by: Jamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:52:15 -07:00
Ralf Baechle 10d024c1b2 [NET]: Nuke SET_MODULE_OWNER macro.
It's been a useless no-op for long enough in 2.6 so I figured it's time to
remove it.  The number of people that could object because they're
maintaining unified 2.4 and 2.6 drivers is probably rather small.

[ Handled drivers added by netdev tree and some missed IRDA cases... -DaveM ]

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:51:13 -07:00
Jesper Dangaard Brouer e9bef55d3d [NET_SCHED]: Cleanup L2T macros and handle oversized packets
Change L2T (length to time) macros, in all rate based schedulers, to
call a common function qdisc_l2t() that does the rate table lookup.
This function handles if the packet size lookup is larger than the
rate table, which often occurs with TSO enabled.

Signed-off-by: Jesper Dangaard Brouer <hawk@comx.dk>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:49:20 -07:00
Eric W. Biederman 881d966b48 [NET]: Make the device list and device lookups per namespace.
This patch makes most of the generic device layer network
namespace safe.  This patch makes dev_base_head a
network namespace variable, and then it picks up
a few associated variables.  The functions:
dev_getbyhwaddr
dev_getfirsthwbytype
dev_get_by_flags
dev_get_by_name
__dev_get_by_name
dev_get_by_index
__dev_get_by_index
dev_ioctl
dev_ethtool
dev_load
wireless_process_ioctl

were modified to take a network namespace argument, and
deal with it.

vlan_ioctl_set and brioctl_set were modified so their
hooks will receive a network namespace argument.

So basically anthing in the core of the network stack that was
affected to by the change of dev_base was modified to handle
multiple network namespaces.  The rest of the network stack was
simply modified to explicitly use &init_net the initial network
namespace.  This can be fixed when those components of the network
stack are modified to handle multiple network namespaces.

For now the ifindex generator is left global.

Fundametally ifindex numbers are per namespace, or else
we will have corner case problems with migration when
we get that far.

At the same time there are assumptions in the network stack
that the ifindex of a network device won't change.  Making
the ifindex number global seems a good compromise until
the network stack can cope with ifindex changes when
you change namespaces, and the like.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:49:10 -07:00
Eric W. Biederman 457c4cbc5a [NET]: Make /proc/net per network namespace
This patch makes /proc/net per network namespace.  It modifies the global
variables proc_net and proc_net_stat to be per network namespace.
The proc_net file helpers are modified to take a network namespace argument,
and all of their callers are fixed to pass &init_net for that argument.
This ensures that all of the /proc/net files are only visible and
usable in the initial network namespace until the code behind them
has been updated to be handle multiple network namespaces.

Making /proc/net per namespace is necessary as at least some files
in /proc/net depend upon the set of network devices which is per
network namespace, and even more files in /proc/net have contents
that are relevant to a single network namespace.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:49:06 -07:00
Stephen Hemminger bea3348eef [NET]: Make NAPI polling independent of struct net_device objects.
Several devices have multiple independant RX queues per net
device, and some have a single interrupt doorbell for several
queues.

In either case, it's easier to support layouts like that if the
structure representing the poll is independant from the net
device itself.

The signature of the ->poll() call back goes from:

	int foo_poll(struct net_device *dev, int *budget)

to

	int foo_poll(struct napi_struct *napi, int budget)

The caller is returned the number of RX packets processed (or
the number of "NAPI credits" consumed if you want to get
abstract).  The callee no longer messes around bumping
dev->quota, *budget, etc. because that is all handled in the
caller upon return.

The napi_struct is to be embedded in the device driver private data
structures.

Furthermore, it is the driver's responsibility to disable all NAPI
instances in it's ->stop() device close handler.  Since the
napi_struct is privatized into the driver's private data structures,
only the driver knows how to get at all of the napi_struct instances
it may have per-device.

With lots of help and suggestions from Rusty Russell, Roland Dreier,
Michael Chan, Jeff Garzik, and Jamal Hadi Salim.

Bug fixes from Thomas Graf, Roland Dreier, Peter Zijlstra,
Joseph Fannin, Scott Wood, Hans J. Koch, and Michael Chan.

[ Ported to current tree and all drivers converted.  Integrated
  Stephen's follow-on kerneldoc additions, and restored poll_list
  handling to the old style to fix mutual exclusion issues.  -DaveM ]

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:47:45 -07:00
Stephen Hemminger bf1b803b01 [PKT_SCHED] cls_u32: error code isn't been propogated properly
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-07 23:57:45 -07:00
Alexey Kuznetsov 32740ddc10 [SFQ]: Remove artificial limitation for queue limit.
This is followup to Patrick's patch. A little optimization to enqueue
routine allows to remove artificial limitation on queue length.

Plus, testing showed that hash function used by SFQ is too bad or even worse.
It does not even sweep the whole range of hash values.
Switched to Jenkins' hash.

Signed-off-by: Alexey Kuznetsov <kaber@ms2.inr.ac.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-01 21:01:23 -07:00
Alexey Kuznetsov 5588b40d7c [PKT_SCHED]: Fix 'SFQ qdisc crashes with limit of 2 packets'
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-20 12:14:08 -07:00
Satyam Sharma ddeee3ce7f [PKT_SCHED]: sch_cbq.c: Shut up uninitialized variable warning
net/sched/sch_cbq.c: In function 'cbq_enqueue':
net/sched/sch_cbq.c:383: warning: 'ret' may be used uninitialized in this function

has been verified to be a bogus case. So let's shut it up.

Signed-off-by: Satyam Sharma <satyam@infradead.org>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-16 14:54:05 -07:00
Jamal Hadi Salim e1e992e52f [NET_SCHED] protect action config/dump from irqs
(with no apologies to C Heston)

On Mon, 2007-10-09 at 21:00 +0800, Herbert Xu wrote:
On Sun, Sep 02, 2007 at 01:11:29PM +0000, Christian Kujau wrote:
> >
> > after upgrading to 2.6.23-rc5 (and applying davem's fix [0]), lockdep
> > was quite noisy when I tried to shape my external (wireless) interface:
> >
> > [ 6400.534545] FahCore_78.exe/3552 just changed the state of lock:
> > [ 6400.534713]  (&dev->ingress_lock){-+..}, at: [<c038d595>]
> > netif_receive_skb+0x2d5/0x3c0
> > [ 6400.534941] but this lock took another, soft-read-irq-unsafe lock in the
> > past:
> > [ 6400.535145]  (police_lock){-.--}
>
> This is a genuine dead-lock.  The police lock can be taken
> for reading with softirqs on.  If a second CPU tries to take
> the police lock for writing, while holding the ingress lock,
> then a softirq on the first CPU can dead-lock when it tries
> to get the ingress lock.

Signed-off-by: Jamal Hadi Salim <hadi@cyberus.ca>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-14 16:43:05 -07:00
Lucas Nussbaum dbaaa07a60 [NET_SCHED] sch_prio.c: remove duplicate call of tc_classify()
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>
2007-08-30 22:35:46 -07:00
Jesper Juhl 0a26f4cdc2 [PKT_SCHED]: Clean up duplicate includes in net/sched/
This patch cleans up duplicate includes in
	net/sched/

Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-08-13 22:52:04 -07:00
Peter P Waskiewicz Jr 0773192b0f [NET]: Fix prio_tune() handling of root qdisc.
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>
2007-07-31 02:28:20 -07:00
Patrick McHardy ffc8fefaf2 [NET]: Fix sch_api to properly set sch->parent on the root.
Fix sch_api to correctly set sch->parent for both ingress and egress
qdiscs in qdisc_create().

Signed-off-by: Patrick McHardy <trash@kaber.net>
Signed-off-by: Peter P Waskiewicz Jr <peter.p.waskiewicz.jr@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-31 02:28:19 -07:00
Patrick McHardy bdba91ec70 [NET_SCHED]: Fix prio/ingress classification logic error
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>
2007-07-31 02:28:18 -07:00
Gabriel Craciunescu 99acaeb92f [PKT_SCHED]: Some typo fixes in net/sched/Kconfig
Signed-off-by: Gabriel Craciunescu <nix.or.die@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-18 02:00:04 -07:00
vignesh babu 782f795689 [ATM]: Replacing kmalloc/memset combination with kzalloc.
Signed-off-by: vignesh babu <vignesh.babu@wipro.com>
Signed-off-by: chas williams <chas@cmf.nrl.navy.mil>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-18 01:46:51 -07:00
Patrick McHardy c3bc7cff8f [NET_SCHED]: Kill CONFIG_NET_CLS_POLICE
The NET_CLS_ACT option is now a full replacement for NET_CLS_POLICE,
remove the old code. The config option will be kept around to select
the equivalent NET_CLS_ACT options for a short time to allow easier
upgrades.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-15 00:03:05 -07:00
Patrick McHardy 73ca4918fb [NET_SCHED]: act_api: qdisc internal reclassify support
The behaviour of NET_CLS_POLICE for TC_POLICE_RECLASSIFY was to return
it to the qdisc, which could handle it internally or ignore it. With
NET_CLS_ACT however, tc_classify starts over at the first classifier
and never returns it to the qdisc. This makes it impossible to support
qdisc-internal reclassification, which in turn makes it impossible to
remove the old NET_CLS_POLICE code without breaking compatibility since
we have two qdiscs (CBQ and ATM) that support this.

This patch adds a tc_classify_compat function that handles
reclassification the old way and changes CBQ and ATM to use it.

This again is of course not fully backwards compatible with the previous
NET_CLS_ACT behaviour. Unfortunately there is no way to fully maintain
compatibility *and* support qdisc internal reclassification with
NET_CLS_ACT, but this seems like the better choice over keeping the two
incompatible options around forever.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-15 00:02:31 -07:00
Patrick McHardy f6853e2df3 [NET_SCHED]: sch_dsmark: act_api support
Handle act_api classification results.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-15 00:02:10 -07:00
Patrick McHardy 9210080445 [NET_SCHED]: sch_atm: act_api support
Handle act_api classification results.

The ATM scheduler behaves slightly different than other schedulers
in that it only handles policer results for successful classifications,
this behaviour is retained for the act_api case.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-15 00:01:49 -07:00
Patrick McHardy b0188d4dbe [NET_SCHED]: sch_atm: Lindent
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-15 00:01:25 -07:00
Patrick McHardy 0621ed2e4e [NET_SCHED]: Revert "avoid transmit softirq on watchdog wakeup" optimization
As noticed by Ranko Zivojnovic <ranko@spidernet.net>, calling qdisc_run
from the timer handler can result in deadlock:

> CPU#0
>
> qdisc_watchdog() fires and gets dev->queue_lock
> qdisc_run()...qdisc_restart()...
> -> releases dev->queue_lock and enters dev_hard_start_xmit()
>
> CPU#1
>
> tc del qdisc dev ...
> qdisc_graft()...dev_graft_qdisc()...dev_deactivate()...
> -> grabs dev->queue_lock ...
>
> qdisc_reset()...{cbq,hfsc,htb,netem,tbf}_reset()...qdisc_watchdog_cancel()...
> -> hrtimer_cancel() - waiting for the qdisc_watchdog() to exit, while still
>		        holding dev->queue_lock
>
> CPU#0
>
> dev_hard_start_xmit() returns ...
> -> wants to get dev->queue_lock(!)
>
> DEADLOCK!

The entire optimization is a bit questionable IMO, it moves potentially
large parts of NET_TX_SOFTIRQ work to TIMER_SOFTIRQ/HRTIMER_SOFTIRQ,
which kind of defeats the separation of them.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Acked-by: Ranko Zivojnovic <ranko@spidernet.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-14 20:49:26 -07:00
Patrick McHardy db3d99c090 [NET_SCHED]: ematch: module autoloading
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-11 19:46:26 -07:00
Ranjit Manomohan c9726d6890 [NET_SCHED]: Make HTB scheduler work with TSO.
Currently the HTB scheduler does not correctly account for TSO packets
which causes large inaccuracies in the bandwidth control when using TSO.
This patch allows the HTB scheduler to work with TSO enabled devices.

Signed-off-by: Ranjit Manomohan <ranjitm@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:43:16 -07:00
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
Patrick McHardy ee39e10c27 [NET_SCHED]: sch_htb: use generic estimator
Use the generic estimator instead of reimplementing (parts of) it.
For compatibility always create a default estimator for new classes.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:16:39 -07:00
Patrick McHardy 4bdf39911e [NET_SCHED]: Remove unnecessary stats_lock pointers
Remove stats_lock pointers from qdisc-internal structures, in all cases
it points to dev->queue_lock. The only case where it is necessary is for
top-level qdiscs, where it might also point to dev->ingress_lock in case
of the ingress qdisc. Also remove it from actions completely, it always
points to the actions internal lock.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:16:38 -07:00
Patrick McHardy 876d48aabf [NET_SCHED]: Remove CONFIG_NET_ESTIMATOR option
The generic estimator is always built in anways and all the config options
does is prevent including a minimal amount of code for setting it up.
Additionally the option is already automatically selected for most cases.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:16:37 -07:00
Peter P Waskiewicz Jr d62733c8e4 [SCHED]: Qdisc changes and sch_rr added for multiqueue
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>
2007-07-10 22:16:22 -07:00
Peter P Waskiewicz Jr f25f4e4480 [CORE] Stack changes to add multiqueue hardware support API
Add the multiqueue hardware device support API to the core network
stack.  Allow drivers to allocate multiple queues and manage them at
the netdev level if they choose to do so.

Added a new field to sk_buff, namely queue_mapping, for drivers to
know which tx_ring to select based on OS classification of the flow.

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>
2007-07-10 22:16:21 -07:00
Krishna Kumar e50c41b53d [NET]: qdisc_restart - couple of optimizations.
Changes :

- netif_queue_stopped need not be called inside qdisc_restart as
  it has been called already in qdisc_run() before the first skb
  is sent, and in __qdisc_run() after each intermediate skb is
  sent (note : we are the only sender, so the queue cannot get
  stopped while the tx lock was got in the ~LLTX case).

- BUG_ON((int) q->q.qlen < 0) was a relic from old times when -1
  meant more packets are available, and __qdisc_run used to loop
  when qdisc_restart() returned -1. During those days, it was
  necessary to make sure that qlen is never less than zero, since
  __qdisc_run would get into an infinite loop if no packets are on
  the queue and this bug in qdisc was there (and worse - no more
  skbs could ever get queue'd as we hold the queue lock too). With
  Herbert's recent change to return values, this check is not
  required.  Hopefully Herbert can validate this change. If at all
  this is required, it should be added to skb_dequeue (in failure
  case), and not to qdisc_qlen.

Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:15:36 -07:00
Krishna Kumar 6c1361a6f2 [NET]: qdisc_restart - readability changes plus one bug fix.
New changes :

- Incorporated Peter Waskiewicz's comments.
- Re-added back one warning message (on driver returning wrong value).

Previous changes :

- Converted to use switch/case code which looks neater.

- "if (ret == NETDEV_TX_LOCKED && lockless)" is buggy, and the lockless
  check should be removed, since driver will return NETDEV_TX_LOCKED only
  if lockless is true and driver has to do the locking. In the original
  code as well as the latest code, this code can result in a bug where
  if LLTX is not set for a driver (lockless == 0) but the driver is written
  wrongly to do a trylock (despite LLTX being set), the driver returns
  LOCKED. But since lockless is zero, the packet is requeue'd instead of
  calling collision code which will issue warning and free up the skb.
  Instead this skb will be retried with this driver next time, and the same
  result will ensue. Removing this check will catch these driver bugs instead
  of hiding the problem. I am keeping this change to readability section
  since :
  	a. it is confusing to check two things as it is; and
  	b. it is difficult to keep this check in the changed 'switch' code.

- Changed some names, like try_get_tx_pkt to dev_dequeue_skb (as that is
  the work being done and easier to understand) and do_dev_requeue to
  dev_requeue_skb, merged handle_dev_cpu_collision and tx_islocked to
  dev_handle_collision (handle_dev_cpu_collision is a small routine with only
  one caller, so there is no need to have two separate routines which also
  results in getting rid of two macros, etc.

- Removed an XXX comment as it should never fail (I suspect this was related
  to batch skb WIP, Jamal ?). Converted some functions to original coding
  style of having the return values and the function name on same line, eg
  prio2list.

Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:15:35 -07:00
Jamal Hadi Salim c716a81ab9 [NET_SCHED]: Cleanup readability of qdisc restart
Over the years this code has gotten hairier. Resulting in many long
discussions over long summer days and patches that get it wrong.
This patch helps tame that code so normal people will understand it.

Thanks to Thomas Graf, Peter J. waskiewicz Jr, and Patrick McHardy
for their valuable reviews.

Signed-off-by: Jamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:06:16 -07:00
Patrick McHardy b00b4bf94e [NET_SCHED]: Fix filter double free
cbq and atm destroy their filters twice when destroying inner classes
during qdisc destruction.

Reported-and-tested-by: Strobl Anton <a.strobl@aws-it.at>

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-06-07 13:41:05 -07:00
Bill Nottingham 75202e7689 [NET]: Fix comparisons of unsigned < 0.
Recent gcc versions emit warnings when unsigned variables are
compared < 0 or >= 0.

Signed-off-by: Bill Nottingham <notting@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-06-03 18:08:47 -07:00
Venkatesh Pallipadi 60468d5b5b [NET]: Make net watchdog timers 1 sec jiffy aligned.
round_jiffies for net dev watchdog timer.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-06-03 18:08:46 -07:00
Patrick McHardy 2e4b3b0e87 [NET_SCHED]: sch_htb: fix event cache time calculation
The event cache time must be an absolute value, when no event exists
it is incorrectly set to 1s instead of 1s in the future.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-05-24 16:36:56 -07:00
Herbert Xu 36247f5421 [NET_SCHED]: Fix qdisc_restart return value when dequeue is empty
My previous patch that changed the return value of qdisc_restart
incorrectly made the case where dequeue returns empty continue
processing packets.

This patch is based on diagnosis and fix by Patrick McHardy.

Reported-and-debugged-by: Anant Nitya <kernel@prachanda.info>

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-05-24 16:36:43 -07:00
Jamal Hadi Salim 3e5c2d3bdb [NET_SCHED]: prio qdisc boundary condition
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>
2007-05-14 02:57:19 -07:00
Herbert Xu 41a23b0788 [NET_SCHED]: Avoid requeue warning on dev_deactivate
When we relinquish queue_lock in qdisc_restart and then retake it for
requeueing, we might race against dev_deactivate and end up requeueing
onto noop_qdisc.  This causes a warning to be printed.

This patch fixes this by checking this before we requeue.  As an added
bonus, we can remove the same check in __qdisc_run which was added to
prevent dev->gso_skb from being requeued when we're shutting down.

Even though we've had to add a new conditional in its place, it's better
because it only happens on requeues rather than every single time that
qdisc_run is called.

For this to work we also need to move the clearing of gso_skb up in
dev_deactivate as now qdisc_restart can occur even after we wait for
__LINK_STATE_QDISC_RUNNING to clear (but it won't do anything as long
as the queue and gso_skb is already clear).

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-05-10 23:47:42 -07:00
Herbert Xu cce1fa36a8 [NET_SCHED]: Reread dev->qdisc for NETDEV_TX_OK
Now that we return the queue length after NETDEV_TX_OK we better
make sure that we have the right queue.  Otherwise we can cause a
stall after a really quick dev_deactive/dev_activate.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-05-10 23:47:41 -07:00
Herbert Xu d90df3ad07 [NET_SCHED]: Rationalise return value of qdisc_restart
The current return value scheme and associated comment was invented
back in the 20th century when we still had that tbusy flag.  Things
have changed quite a bit since then (even Tony Blair is moving on
now, not to mention the new French president).

All we need to indicate now is whether the caller should continue
processing the queue.  Therefore it's sufficient if we return 0 if
we want to stop and non-zero otherwise.

This is based on a patch by Krishna Kumar.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-05-10 23:47:40 -07:00
Thomas Graf 5830725f8a [NET]: Fix dev->qdisc race for NETDEV_TX_LOCKED case
When transmit fails with NETDEV_TX_LOCKED the skb is requeued
to dev->qdisc again. The dev->qdisc pointer is protected by
the queue lock which needs to be dropped when attempting to
transmit and acquired again before requeing. The problem is
that qdisc_restart() fetches the dev->qdisc pointer once and
stores it in the `q' variable which is invalidated when
dropping the queue_lock, therefore the variable needs to be
refreshed before requeueing.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-05-10 23:47:39 -07:00