linux-stable.git/include/net/sch_generic.h, branch linux-2.6.38.y

net_sched: long word align struct qdisc_skb_cb data

2011-02-23T22:17:02+00:00

netem_skb_cb() does :

return (struct netem_skb_cb *)qdisc_skb_cb(skb)->data;

Unfortunatly struct qdisc_skb_cb data is not long word aligned, so
access to psched_time_t time_to_send uses a non aligned access.

Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller

net_sched: accurate bytes/packets stats/rates

2011-01-21T07:31:33+00:00

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.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 
Acked-by: Stephen Hemminger 
Signed-off-by: David S. Miller

net_sched: factorize qdisc stats handling

2011-01-11T00:07:54+00:00

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 
Signed-off-by: David S. Miller

Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6

2010-12-20T21:24:14+00:00

net_sched: always clone skbs

2010-12-20T18:27:19+00:00

Pawel reported a panic related to handling shared skbs in ixgbe
incorrectly. So we need to revert my previous patch to work around
this bug. Instead of reverting the patch completely, I just revert
the essential lines, so we can add the previous optimization
back more easily in future.

    commit 3511c9132f8b1e1b5634e41a3331c44b0c13be70
    Author: Changli Gao 
    Date:   Sat Oct 16 13:04:08 2010 +0000

        net_sched: remove the unused parameter of qdisc_create_dflt()

Reported-by: Pawel Staszewski 
Signed-off-by: Changli Gao 
Acked-by: Eric Dumazet 
Signed-off-by: David S. Miller

net: factorize sync-rcu call in unregister_netdevice_many

2010-12-16T22:04:44+00:00

Add dev_close_many and dev_deactivate_many to factorize another
sync-rcu operation on the netdevice unregister path.

$ modprobe dummy numdummies=10000
$ ip link set dev dummy* up
$ time rmmod dummy

Without the patch           With the patch

real    0m 24.63s           real    0m 5.15s
user    0m 0.00s            user    0m 0.00s
sys     0m 6.05s            sys     0m 5.14s

Signed-off-by: Octavian Purdila 
Signed-off-by: David S. Miller

net_sched: remove the unused parameter of qdisc_create_dflt()

2010-10-21T10:09:47+00:00

The first parameter dev isn't in use in qdisc_create_dflt().

Signed-off-by: Changli Gao 
Acked-by: Jamal Hadi Salim 
Signed-off-by: David S. Miller

net: return operator cleanup

2010-09-23T21:33:39+00:00

Change "return (EXPR);" to "return EXPR;"

return is not a function, parentheses are not required.

Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller

Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6

2010-07-07T22:59:38+00:00

net: decreasing real_num_tx_queues needs to flush qdisc

2010-07-03T04:59:07+00:00

Reducing real_num_queues needs to flush the qdisc otherwise
skbs with queue_mappings greater then real_num_tx_queues can
be sent to the underlying driver.

The flow for this is,

dev_queue_xmit()
	dev_pick_tx()
		skb_tx_hash()  => hash using real_num_tx_queues
		skb_set_queue_mapping()
	...
	qdisc_enqueue_root() => enqueue skb on txq from hash
...
dev->real_num_tx_queues -= n
...
sch_direct_xmit()
	dev_hard_start_xmit()
		ndo_start_xmit(skb,dev) => skb queue set with old hash

skbs are enqueued on the qdisc with skb->queue_mapping set
0 < queue_mappings < real_num_tx_queues.  When the driver
decreases real_num_tx_queues skb's may be dequeued from the
qdisc with a queue_mapping greater then real_num_tx_queues.

This fixes a case in ixgbe where this was occurring with DCB
and FCoE. Because the driver is using queue_mapping to map
skbs to tx descriptor rings we can potentially map skbs to
rings that no longer exist.

Signed-off-by: John Fastabend 
Tested-by: Ross Brattain 
Signed-off-by: Jeff Kirsher 
Signed-off-by: David S. Miller