Commit Graph

439 Commits

Author SHA1 Message Date
David S. Miller
a0c80b80e0 pkt_sched: Make default qdisc nonshared-multiqueue safe.
Instead of 'pfifo_fast' we have just plain 'fifo_fast'.
No priority queues, just a straight FIFO.

This is necessary in order to legally have a seperate
qdisc per queue in multi-TX-queue setups, and thus get
full parallelization.

Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-17 19:21:33 -07:00
David S. Miller
99194cff39 pkt_sched: Add multiqueue handling to qdisc_graft().
Move the destruction of the old queue into qdisc_graft().

When operating on a root qdisc (ie. "parent == NULL"), apply
the operation to all queues.  The caller has grabbed a single
implicit reference for this graft, therefore when we apply the
change to more than one queue we must grab additional qdisc
references.

Otherwise, we are operating on a class of a specific parent qdisc, and
therefore no multiqueue handling is necessary.

Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-17 19:21:30 -07:00
David S. Miller
8387400092 pkt_sched: Kill netdev_queue lock.
We can simply use the qdisc->q.lock for all of the
qdisc tree synchronization.

Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-17 19:21:30 -07:00
David S. Miller
c7e4f3bbb4 pkt_sched: Kill qdisc_lock_tree and qdisc_unlock_tree.
No longer used.

Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-17 19:21:29 -07:00
David S. Miller
53049978df pkt_sched: Make qdisc grafting locking more specific.
Lock the root of the qdisc being operated upon.

All explicit references to qdisc_tree_lock() are now gone.
The only remaining uses are via the sch_tree_{lock,unlock}()
and tcf_tree_{lock,unlock}() macros.

Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-17 19:21:27 -07:00
David S. Miller
ead81cc5fc netdevice: Move qdisc_list back into net_device proper.
And give it it's own lock.

Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-17 19:21:26 -07:00
David S. Miller
15b458fa65 pkt_sched: Kill qdisc_lock_tree usage in cls_route.c
It just wants the qdisc tree to be synchronized, so grabbing
qdisc_root_lock() is sufficient.

Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-17 19:21:25 -07:00
David S. Miller
55dbc640c3 pkt_sched: Remove qdisc_lock_tree usage in cls_api.c
It just wants the qdisc tree for the filter to be synchronized.
So just BH lock qdisc_root_lock(q) instead.

Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-17 19:21:24 -07:00
David S. Miller
17715e62a5 pkt_sched: Use per-queue locking in shutdown_scheduler_queue.
This eliminates another qdisc_lock_tree user.

Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-17 19:21:23 -07:00
David S. Miller
8a34c5dc3a pkt_sched: Perform bulk of qdisc destruction in RCU.
This allows less strict control of access to the qdisc attached to a
netdev_queue.  It is even allowed to enqueue into a qdisc which is
in the process of being destroyed.  The RCU handler will toss out
those packets.

We will need this to handle sharing of a qdisc amongst multiple
TX queues.  In such a setup the lock has to be shared, so will
be inside of the qdisc itself.  At which point the netdev_queue
lock cannot be used to hard synchronize access to the ->qdisc
pointer.

One operation we have to keep inside of qdisc_destroy() is the list
deletion.  It is the only piece of state visible after the RCU quiesce
period, so we have to undo it early and under the appropriate locking.

The operations in the RCU handler do not need any looking because the
qdisc tree is no longer visible to anything at that point.

Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-17 19:21:22 -07:00
David S. Miller
16361127eb pkt_sched: dev_init_scheduler() does not need to lock qdisc tree.
We are registering the device, there is no way anyone can get
at this object's qdiscs yet in any meaningful way.

Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-17 19:21:21 -07:00
David S. Miller
37437bb2e1 pkt_sched: Schedule qdiscs instead of netdev_queue.
When we have shared qdiscs, packets come out of the qdiscs
for multiple transmit queues.

Therefore it doesn't make any sense to schedule the transmit
queue when logically we cannot know ahead of time the TX
queue of the SKB that the qdisc->dequeue() will give us.

Just for sanity I added a BUG check to make sure we never
get into a state where the noop_qdisc is scheduled.

Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-17 19:21:20 -07:00
David S. Miller
7698b4fcab pkt_sched: Add and use qdisc_root() and qdisc_root_lock().
When code wants to lock the qdisc tree state, the logic
operation it's doing is locking the top-level qdisc that
sits of the root of the netdev_queue.

Add qdisc_root_lock() to represent this and convert the
easiest cases.

In order for this to work out in all cases, we have to
hook up the noop_qdisc to a dummy netdev_queue.

Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-17 19:21:19 -07:00
David S. Miller
e2627c8c22 pkt_sched: Make QDISC_RUNNING a qdisc state.
Currently it is associated with a netdev_queue, but when we have
qdisc sharing that no longer makes any sense.

Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-17 19:21:18 -07:00
David S. Miller
d3b753db7c pkt_sched: Move gso_skb into Qdisc.
We liberate any dangling gso_skb during qdisc destruction.

It really only matters for the root qdisc.  But when qdiscs
can be shared by multiple netdev_queue objects, we can't
have the gso_skb in the netdev_queue any more.

Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-17 19:21:18 -07:00
David S. Miller
fd2ea0a79f net: Use queue aware tests throughout.
This effectively "flips the switch" by making the core networking
and multiqueue-aware drivers use the new TX multiqueue structures.

Non-multiqueue drivers need no changes.  The interfaces they use such
as netif_stop_queue() degenerate into an operation on TX queue zero.
So everything "just works" for them.

Code that really wants to do "X" to all TX queues now invokes a
routine that does so, such as netif_tx_wake_all_queues(),
netif_tx_stop_all_queues(), etc.

pktgen and netpoll required a little bit more surgery than the others.

In particular the pktgen changes, whilst functional, could be largely
improved.  The initial check in pktgen_xmit() will sometimes check the
wrong queue, which is mostly harmless.  The thing to do is probably to
invoke fill_packet() earlier.

The bulk of the netpoll changes is to make the code operate solely on
the TX queue indicated by by the SKB queue mapping.

Setting of the SKB queue mapping is entirely confined inside of
net/core/dev.c:dev_pick_tx().  If we end up needing any kind of
special semantics (drops, for example) it will be implemented here.

Finally, we now have a "real_num_tx_queues" which is where the driver
indicates how many TX queues are actually active.

With IGB changes from Jeff Kirsher.

Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-17 19:21:07 -07:00
David S. Miller
1d8ae3fdeb pkt_sched: Remove RR scheduler.
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>
2008-07-17 19:21:04 -07:00
David S. Miller
e8a0464cc9 netdev: Allocate multiple queues for TX.
alloc_netdev_mq() now allocates an array of netdev_queue
structures for TX, based upon the queue_count argument.

Furthermore, all accesses to the TX queues are now vectored
through the netdev_get_tx_queue() and netdev_for_each_tx_queue()
interfaces.  This makes it easy to grep the tree for all
things that want to get to a TX queue of a net device.

Problem spots which are not really multiqueue aware yet, and
only work with one queue, can easily be spotted by grepping
for all netdev_get_tx_queue() calls that pass in a zero index.

Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-17 19:21:00 -07:00
Patrick McHardy
72d9794f44 net-sched: cls_flow: add perturbation support
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-14 20:36:32 -07:00
David S. Miller
79d16385c7 netdev: Move atomic queue state bits into netdev_queue.
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-08 23:14:46 -07:00
David S. Miller
c773e847ea netdev: Move _xmit_lock and xmit_lock_owner into netdev_queue.
Accesses are mostly structured such that when there are multiple TX
queues the code transformations will be a little bit simpler.

Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-08 23:13:53 -07:00
David S. Miller
eb6aafe3f8 pkt_sched: Make qdisc_run take a netdev_queue.
This allows us to use this calling convention all the way down into
qdisc_restart().

Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-08 23:12:38 -07:00
David S. Miller
86d804e10a netdev: Make netif_schedule() routines work with netdev_queue objects.
Only plain netif_schedule() remains taking a net_device, mostly as a
compatability item while we transition the rest of these interfaces.

Everything else calls netif_schedule_queue() or __netif_schedule(),
both of which take a netdev_queue pointer.

Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-08 23:11:25 -07:00
David S. Miller
970565bbad netdev: Move gso_skb into netdev_queue.
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-08 23:10:33 -07:00
David S. Miller
74d58a0c1d pkt_sched: Make netem queue agnostic.
It just wants the root qdisc given an arbitrary qdisc,
and that is simply qdisc->dev_queue->qdisc

Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
2008-07-08 22:57:51 -07:00
David S. Miller
68dfb42798 pkt_sched: Kill stats_lock member of struct Qdisc.
It is always equal to qdisc->dev_queue->lock

Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-08 22:57:31 -07:00
David S. Miller
816f3258e7 netdev: Kill qdisc_ingress, use netdev->rx_queue.qdisc instead.
Now that our qdisc management is bi-directional, per-queue, and fully
orthogonal, there is no reason to have a special ingress qdisc pointer
in struct net_device.

Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-08 22:49:00 -07:00
David S. Miller
b0e1e6462d netdev: Move rest of qdisc state into struct netdev_queue
Now qdisc, qdisc_sleeping, and qdisc_list also live there.

Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-08 17:42:10 -07:00
David S. Miller
555353cfa1 netdev: The ingress_lock member is no longer needed.
Every qdisc is assosciated with a queue, and in the case of ingress
qdiscs that will now be netdev->rx_queue so using that queue's lock is
the thing to do.

Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-08 17:33:13 -07:00
David S. Miller
dc2b48475a netdev: Move queue_lock into struct netdev_queue.
The lock is now an attribute of the device queue.

One thing to notice is that "suspicious" places
emerge which will need specific training about
multiple queue handling.  They are so marked with
explicit "netdev->rx_queue" and "netdev->tx_queue"
references.

Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-08 17:18:23 -07:00
David S. Miller
5ce2d488fe pkt_sched: Remove 'dev' member of struct Qdisc.
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>
2008-07-08 17:06:30 -07:00
David S. Miller
bb949fbd18 netdev: Create netdev_queue abstraction.
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>
2008-07-08 16:55:56 -07:00
David S. Miller
e65d22e180 pkt_sched: Remove comment reference to old style TX locking.
We haven't had netdev->tbusy in many years :)

Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-08 16:46:01 -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
Patrick McHardy
aee18a8cf2 net-sched: sch_htb: remove write-only qdisc filter_cnt
The filter_cnt is supposed to count filter references to a class.
Since the qdisc can't be the target of a filter, it doesn't need
a filter_cnt. In fact the counter is never decreased since cls_api
considers a return value of zero a failure and doesn't unbind again.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-05 23:23:27 -07:00
Patrick McHardy
4207759939 net-sched: sch_htb: remove child and sibling lists
Now that the qdisc isn't destroyed in hierarchical order anymore,
the only user of the child lists left is htb_parent_last_child().
This can be easily changed to use a counter of children to save
a few bytes.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-05 23:22:53 -07:00
Patrick McHardy
f4c1f3e0c5 net-sched: sch_htb: use dynamic class hash helpers
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-05 23:22:35 -07:00
Patrick McHardy
fbd8f1379a net-sched: sch_htb: move hash and sibling list removal to htb_delete
Hash list removal currently happens twice (once in htb_delete, once
in htb_destroy_class), which makes it harder to use the dynamically
sized class hash without adding special cases for HTB. The reason is
that qdisc destruction destroys classes in hierarchical order, which
is not necessary if filters are destroyed in a separate iteration
during qdisc destruction.

Adjust qdisc destruction to follow the same scheme as other hierarchical
qdiscs by first performing a filter destruction pass, then destroying
all classes in hash order.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-05 23:22:19 -07:00
Patrick McHardy
d77fea2eb9 net-sched: sch_cbq: use dynamic class hash helpers
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-05 23:22:05 -07:00
Patrick McHardy
be0d39d52c net-sched: sch_hfsc: use dynamic class hash helpers
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-05 23:21:47 -07:00
Patrick McHardy
6fe1c7a555 net-sched: add dynamically sized qdisc class hash helpers
Currently all qdiscs which allow to create classes uses a fixed sized hash
table with size 16 to hash the classes. This causes a large bottleneck
when using thousands of classes and unbound filters.

Add helpers for dynamically sized class hashes to fix this. The following
patches will convert the qdiscs to use them.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-05 23:21:31 -07:00
David S. Miller
ea2aca084b Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:

	Documentation/feature-removal-schedule.txt
	drivers/net/wan/hdlc_fr.c
	drivers/net/wireless/iwlwifi/iwl-4965.c
	drivers/net/wireless/iwlwifi/iwl3945-base.c
2008-07-05 23:08:07 -07:00
Patrick McHardy
a4aebb83cf net-sched: fix filter destruction in atm/hfsc qdisc destruction
Filters need to be destroyed before beginning to destroy classes
since the destination class needs to still be alive to unbind the
filter.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-01 19:53:09 -07:00
Patrick McHardy
ff31ab56c0 net-sched: change tcf_destroy_chain() to clear start of filter list
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>
2008-07-01 19:52:38 -07:00
David S. Miller
1b63ba8a86 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:

	drivers/net/wireless/iwlwifi/iwl4965-base.c
2008-06-28 01:19:40 -07:00
Adrian Bunk
ede16af4cd pkt_sched: Remove CONFIG_NET_SCH_RR
Commit d62733c8e4
([SCHED]: Qdisc changes and sch_rr added for multiqueue)
added a NET_SCH_RR option that was unused since the code
went unconditionally into sch_prio.

Reported-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-06-27 19:54:05 -07:00
WANG Cong
01e123d79a pkt_sched: ERR_PTR() ususally encodes an negative errno, not positive.
Note, in the following patch, 'err' is initialized as:

int err = -ENOBUFS;

Signed-off-by: WANG Cong <wcong@critical-links.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-06-27 19:51:35 -07:00
David S. Miller
caea902f72 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:

	drivers/net/wireless/rt2x00/Kconfig
	drivers/net/wireless/rt2x00/rt2x00usb.c
	net/sctp/protocol.c
2008-06-16 18:25:48 -07:00
Jesper Dangaard Brouer
47083fc073 pkt_sched: Change HTB_HYSTERESIS to a runtime parameter htb_hysteresis.
Add a htb_hysteresis parameter to htb_sch.ko and by sysfs magic make
it runtime adjustable via
/sys/module/sch_htb/parameters/htb_hysteresis mode 640.

Signed-off-by: Jesper Dangaard Brouer <hawk@comx.dk>
Acked-by: Martin Devera <devik@cdi.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-06-16 16:39:32 -07:00
Jesper Dangaard Brouer
f9ffcedddb pkt_sched: HTB scheduler, change default hysteresis mode to off.
The HTB hysteresis mode reduce the CPU load, but at the
cost of scheduling accuracy.

On ADSL links (512 kbit/s upstream), this inaccuracy introduce
significant jitter, enought to disturbe VoIP.  For details see my
masters thesis (http://www.adsl-optimizer.dk/thesis/), chapter 7,
section 7.3.1, pp 69-70.

Signed-off-by: Jesper Dangaard Brouer <hawk@comx.dk>
Acked-by: Martin Devera <devik@cdi.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-06-16 16:38:33 -07:00