linux/include/net/sch_generic.h, branch v3.0.62

bonding: Fix corrupted queue_mapping

2012-07-16T15:47:37Z

[ Upstream commit 5ee31c6898ea5537fcea160999d60dc63bc0c305 ] In the transmit path of the bonding driver, skb->cb is used to stash the skb->queue_mapping so that the bonding device can set its own queue mapping. This value becomes corrupted since the skb->cb is also used in __dev_xmit_skb. When transmitting through bonding driver, bond_select_queue is called from dev_queue_xmit. In bond_select_queue the original skb->queue_mapping is copied into skb->cb (via bond_queue_mapping) and skb->queue_mapping is overwritten with the bond driver queue. Subsequently in dev_queue_xmit, __dev_xmit_skb is called which writes the packet length into skb->cb, thereby overwriting the stashed queue mappping. In bond_dev_queue_xmit (called from hard_start_xmit), the queue mapping for the skb is set to the stashed value which is now the skb length and hence is an invalid queue for the slave device. If we want to save skb->queue_mapping into skb->cb[], best place is to add a field in struct qdisc_skb_cb, to make sure it wont conflict with other layers (eg : Qdiscc, Infiniband...) This patchs also makes sure (struct qdisc_skb_cb)->data is aligned on 8 bytes : netem qdisc for example assumes it can store an u64 in it, without misalignment penalty. Note : we only have 20 bytes left in (struct qdisc_skb_cb)->data[]. The largest user is CHOKe and it fills it. Based on a previous patch from Tom Herbert. Signed-off-by: Eric Dumazet Reported-by: Tom Herbert Cc: John Fastabend Cc: Roland Dreier Acked-by: Neil Horman Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: Make qdisc_skb_cb upper size bound explicit.

2012-03-01T00:33:44Z

[ Upstream commit 16bda13d90c8d5da243e2cfa1677e62ecce26860 ] Just like skb->cb[], so that qdisc_skb_cb can be encapsulated inside of other data structures. This is intended to be used by IPoIB so that it can remember addressing information stored at hard_header_ops->create() time that it can fetch when the packet gets to the transmit routine. Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net_sched: fix THROTTLED/RUNNING race

2011-03-24T07:13:14Z

commit fd245a4adb52 (net_sched: move TCQ_F_THROTTLED flag) added a race. qdisc_watchdog() is run from softirq, so special care should be taken or we can lose one state transition (THROTTLED/RUNNING) Prior to fd245a4adb52, we were manipulating q->flags (qdisc->flags &= ~TCQ_F_THROTTLED;) and this manipulation could only race with qdisc_warn_nonwc(). Since we want to avoid atomic ops in qdisc fast path - it was the meaning of commit 371121057607e (QDISC_STATE_RUNNING dont need atomic bit ops) - fix is to move THROTTLE bit into 'state' field, this one being manipulated with SMP and IRQ safe operations. 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

2011-03-04T05:27:42Z

Conflicts: drivers/net/bnx2x/bnx2x.h

net_sched: reduce fifo qdisc size

2011-03-03T19:10:02Z

Because of various alignements [SLUB / qdisc], we use 512 bytes of memory for one {p|b}fifo qdisc, instead of 256 bytes on 64bit arches and 192 bytes on 32bit ones. Move the "u32 limit" inside "struct Qdisc" (no impact on other qdiscs) Change qdisc_alloc(), first trying a regular allocation before an oversized one. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller

net_sched: long word align struct qdisc_skb_cb data

2011-02-23T22:17:02Z

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

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

2011-01-24T22:09:35Z

Conflicts: net/sched/sch_hfsc.c net/sched/sch_htb.c net/sched/sch_tbf.c

net_sched: accurate bytes/packets stats/rates

2011-01-21T07:31:33Z

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: RCU conversion of stab

2011-01-21T00:59:32Z

This patch converts stab qdisc management to RCU, so that we can perform the qdisc_calculate_pkt_len() call before getting qdisc lock. This shortens the lock's held time in __dev_xmit_skb(). This permits more qdiscs to get TCQ_F_CAN_BYPASS status, avoiding lot of cache misses and so reducing latencies. 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

net_sched: move TCQ_F_THROTTLED flag

2011-01-21T00:59:32Z

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