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2012-05-10codel: Controlled Delay AQMEric Dumazet3-0/+287
An implementation of CoDel AQM, from Kathleen Nichols and Van Jacobson. http://queue.acm.org/detail.cfm?id=2209336 This AQM main input is no longer queue size in bytes or packets, but the delay packets stay in (FIFO) queue. As we don't have infinite memory, we still can drop packets in enqueue() in case of massive load, but mean of CoDel is to drop packets in dequeue(), using a control law based on two simple parameters : target : target sojourn time (default 5ms) interval : width of moving time window (default 100ms) Based on initial work from Dave Taht. Refactored to help future codel inclusion as a plugin for other linux qdisc (FQ_CODEL, ...), like RED. include/net/codel.h contains codel algorithm as close as possible than Kathleen reference. net/sched/sch_codel.c contains the linux qdisc specific glue. Separate structures permit a memory efficient implementation of fq_codel (to be sent as a separate work) : Each flow has its own struct codel_vars. timestamps are taken at enqueue() time with 1024 ns precision, allowing a range of 2199 seconds in queue, and 100Gb links support. iproute2 uses usec as base unit. Selected packets are dropped, unless ECN is enabled and packets can get ECN mark instead. Tested from 2Mb to 10Gb speeds with no particular problems, on ixgbe and tg3 drivers (BQL enabled). Usage: tc qdisc ... codel [ limit PACKETS ] [ target TIME ] [ interval TIME ] [ ecn ] qdisc codel 10: parent 1:1 limit 2000p target 3.0ms interval 60.0ms ecn Sent 13347099587 bytes 8815805 pkt (dropped 0, overlimits 0 requeues 0) rate 202365Kbit 16708pps backlog 113550b 75p requeues 0 count 116 lastcount 98 ldelay 4.3ms dropping drop_next 816us maxpacket 1514 ecn_mark 84399 drop_overlimit 0 CoDel must be seen as a base module, and should be used keeping in mind there is still a FIFO queue. So a typical setup will probably need a hierarchy of several qdiscs and packet classifiers to be able to meet whatever constraints a user might have. One possible example would be to use fq_codel, which combines Fair Queueing and CoDel, in replacement of sfq / sfq_red. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Dave Taht <dave.taht@bufferbloat.net> Cc: Kathleen Nichols <nichols@pollere.com> Cc: Van Jacobson <van@pollere.net> Cc: Tom Herbert <therbert@google.com> Cc: Matt Mathis <mattmathis@google.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-05-10net_sched: update bstats in dequeue()Eric Dumazet4-6/+6
Class bytes/packets stats can be misleading because they are updated in enqueue() while packet might be dropped later. We already fixed all qdiscs but sch_atm. This patch makes the final cleanup. class rate estimators can now match qdisc ones. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-05-07Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-4/+2
Conflicts: drivers/net/ethernet/intel/e1000e/param.c drivers/net/wireless/iwlwifi/iwl-agn-rx.c drivers/net/wireless/iwlwifi/iwl-trans-pcie-rx.c drivers/net/wireless/iwlwifi/iwl-trans.h Resolved the iwlwifi conflict with mainline using 3-way diff posted by John Linville and Stephen Rothwell. In 'net' we added a bug fix to make iwlwifi report a more accurate skb->truesize but this conflicted with RX path changes that happened meanwhile in net-next. In e1000e a conflict arose in the validation code for settings of adapter->itr. 'net-next' had more sophisticated logic so that logic was used. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-05-04net: sched: factorize code (qdisc_drop())Eric Dumazet4-13/+6
Use qdisc_drop() helper where possible. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-05-01netem: fix possible skb leakEric Dumazet1-4/+2
skb_checksum_help(skb) can return an error, we must free skb in this case. qdisc_drop(skb, sch) can also be feeded with a NULL skb (if skb_unshare() failed), so lets use this generic helper. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Stephen Hemminger <shemminger@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-05-01netem: add ECN capabilityEric Dumazet1-3/+15
Add ECN (Explicit Congestion Notification) marking capability to netem tc qdisc add dev eth0 root netem drop 0.5 ecn Instead of dropping packets, try to ECN mark them. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Neal Cardwell <ncardwell@google.com> Cc: Tom Herbert <therbert@google.com> Cc: Hagen Paul Pfeifer <hagen@jauu.net> Cc: Stephen Hemminger <shemminger@vyatta.com> Acked-by: Hagen Paul Pfeifer <hagen@jauu.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-23Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-5/+2
Fix merge between commit 3adadc08cc1e ("net ax25: Reorder ax25_exit to remove races") and commit 0ca7a4c87d27 ("net ax25: Simplify and cleanup the ax25 sysctl handling") The former moved around the sysctl register/unregister calls, the later simply removed them. With help from Stephen Rothwell. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-16net_sched: gred: Fix oops in gred_dump() in WRED modeDavid Ward1-5/+2
A parameter set exists for WRED mode, called wred_set, to hold the same values for qavg and qidlestart across all VQs. The WRED mode values had been previously held in the VQ for the default DP. After these values were moved to wred_set, the VQ for the default DP was no longer created automatically (so that it could be omitted on purpose, to have packets in the default DP enqueued directly to the device without using RED). However, gred_dump() was overlooked during that change; in WRED mode it still reads qavg/qidlestart from the VQ for the default DP, which might not even exist. As a result, this command sequence will cause an oops: tc qdisc add dev $DEV handle $HANDLE parent $PARENT gred setup \ DPs 3 default 2 grio tc qdisc change dev $DEV handle $HANDLE gred DP 0 prio 8 $RED_OPTIONS tc qdisc change dev $DEV handle $HANDLE gred DP 1 prio 8 $RED_OPTIONS This fixes gred_dump() in WRED mode to use the values held in wred_set. Signed-off-by: David Ward <david.ward@ll.mit.edu> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-01pkt_sched: Stop using NLA_PUT*().David S. Miller40-157/+263
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>
2012-04-01cgroup: convert all non-memcg controllers to the new cftype interfaceTejun Heo1-6/+2
Convert debug, freezer, cpuset, cpu_cgroup, cpuacct, net_prio, blkio, net_cls and device controllers to use the new cftype based interface. Termination entry is added to cftype arrays and populate callbacks are replaced with cgroup_subsys->base_cftypes initializations. This is functionally identical transformation. There shouldn't be any visible behavior change. memcg is rather special and will be converted separately. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizf@cn.fujitsu.com> Cc: Paul Menage <paul@paulmenage.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <peterz@infradead.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Vivek Goyal <vgoyal@redhat.com>
2012-04-01cgroup: relocate cftype and cgroup_subsys definitions in controllersTejun Heo1-16/+11
blk-cgroup, netprio_cgroup, cls_cgroup and tcp_memcontrol unnecessarily define cftype array and cgroup_subsys structures at the top of the file, which is unconventional and necessiates forward declaration of methods. This patch relocates those below the definitions of the methods and removes the forward declarations. Note that forward declaration of tcp_files[] is added in tcp_memcontrol.c for tcp_init_cgroup(). This will be removed soon by another patch. This patch doesn't introduce any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizf@cn.fujitsu.com>
2012-03-20Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds3-0/+260
Pull networking merge from David Miller: "1) Move ixgbe driver over to purely page based buffering on receive. From Alexander Duyck. 2) Add receive packet steering support to e1000e, from Bruce Allan. 3) Convert TCP MD5 support over to RCU, from Eric Dumazet. 4) Reduce cpu usage in handling out-of-order TCP packets on modern systems, also from Eric Dumazet. 5) Support the IP{,V6}_UNICAST_IF socket options, making the wine folks happy, from Erich Hoover. 6) Support VLAN trunking from guests in hyperv driver, from Haiyang Zhang. 7) Support byte-queue-limtis in r8169, from Igor Maravic. 8) Outline code intended for IP_RECVTOS in IP_PKTOPTIONS existed but was never properly implemented, Jiri Benc fixed that. 9) 64-bit statistics support in r8169 and 8139too, from Junchang Wang. 10) Support kernel side dump filtering by ctmark in netfilter ctnetlink, from Pablo Neira Ayuso. 11) Support byte-queue-limits in gianfar driver, from Paul Gortmaker. 12) Add new peek socket options to assist with socket migration, from Pavel Emelyanov. 13) Add sch_plug packet scheduler whose queue is controlled by userland daemons using explicit freeze and release commands. From Shriram Rajagopalan. 14) Fix FCOE checksum offload handling on transmit, from Yi Zou." * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1846 commits) Fix pppol2tp getsockname() Remove printk from rds_sendmsg ipv6: fix incorrent ipv6 ipsec packet fragment cpsw: Hook up default ndo_change_mtu. net: qmi_wwan: fix build error due to cdc-wdm dependecy netdev: driver: ethernet: Add TI CPSW driver netdev: driver: ethernet: add cpsw address lookup engine support phy: add am79c874 PHY support mlx4_core: fix race on comm channel bonding: send igmp report for its master fs_enet: Add MPC5125 FEC support and PHY interface selection net: bpf_jit: fix BPF_S_LDX_B_MSH compilation net: update the usage of CHECKSUM_UNNECESSARY fcoe: use CHECKSUM_UNNECESSARY instead of CHECKSUM_PARTIAL on tx net: do not do gso for CHECKSUM_UNNECESSARY in netif_needs_gso ixgbe: Fix issues with SR-IOV loopback when flow control is disabled net/hyperv: Fix the code handling tx busy ixgbe: fix namespace issues when FCoE/DCB is not enabled rtlwifi: Remove unused ETH_ADDR_LEN defines igbvf: Use ETH_ALEN ... Fix up fairly trivial conflicts in drivers/isdn/gigaset/interface.c and drivers/net/usb/{Kconfig,qmi_wwan.c} as per David.
2012-03-20Merge branch 'for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroupLinus Torvalds1-6/+4
Pull cgroup changes from Tejun Heo: "Out of the 8 commits, one fixes a long-standing locking issue around tasklist walking and others are cleanups." * 'for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: cgroup: Walk task list under tasklist_lock in cgroup_enable_task_cg_list cgroup: Remove wrong comment on cgroup_enable_task_cg_list() cgroup: remove cgroup_subsys argument from callbacks cgroup: remove extra calls to find_existing_css_set cgroup: replace tasklist_lock with rcu_read_lock cgroup: simplify double-check locking in cgroup_attach_proc cgroup: move struct cgroup_pidlist out from the header file cgroup: remove cgroup_attach_task_current_cg()
2012-03-18Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-1/+5
2012-03-16sch_sfq: revert dont put new flow at the end of flowsEric Dumazet1-1/+5
This reverts commit d47a0ac7b6 (sch_sfq: dont put new flow at the end of flows) As Jesper found out, patch sounded great but has bad side effects. In stress situation, pushing new flows in front of the queue can prevent old flows doing any progress. Packets can stay in SFQ queue for unlimited amount of time. It's possible to add heuristics to limit this problem, but this would add complexity outside of SFQ scope. A more sensible answer to Dave Taht concerns (who reported the issued I tried to solve in original commit) is probably to use a qdisc hierarchy so that high prio packets dont enter a potentially crowded SFQ qdisc. Reported-by: Jesper Dangaard Brouer <jdb@comx.dk> Cc: Dave Taht <dave.taht@gmail.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-02-26Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-4/+2
Conflicts: drivers/net/ethernet/sfc/rx.c Overlapping changes in drivers/net/ethernet/sfc/rx.c, one to change the rx_buf->is_page boolean into a set of u16 flags, and another to adjust how ->ip_summed is initialized. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-02-19netem: fix dequeueEric Dumazet1-4/+2
commit 50612537e9 (netem: fix classful handling) added two errors in netem_dequeue() 1) After checking skb at the head of tfifo queue for time constraints, it dequeues tail skb, thus adding unwanted reordering. 2) qdisc stats are updated twice per packet (one when packet dequeued from tfifo, once when delivered) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-02-13net_sched: sch_plug: plug_qdisc_ops is staticEric Dumazet1-1/+1
net/sched/sch_plug.c:211:18: warning: symbol 'plug_qdisc_ops' was not declared. Should it be static? Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-02-09net: Make qdisc_skb_cb upper size bound explicit.David S. Miller4-9/+5
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 <davem@davemloft.net>
2012-02-07net/sched: sch_plug - Queue traffic until an explicit release commandShriram Rajagopalan3-0/+260
The qdisc supports two operations - plug and unplug. When the qdisc receives a plug command via netlink request, packets arriving henceforth are buffered until a corresponding unplug command is received. Depending on the type of unplug command, the queue can be unplugged indefinitely or selectively. This qdisc can be used to implement output buffering, an essential functionality required for consistent recovery in checkpoint based fault-tolerance systems. Output buffering enables speculative execution by allowing generated network traffic to be rolled back. It is used to provide network protection for Xen Guests in the Remus high availability project, available as part of Xen. This module is generic enough to be used by any other system that wishes to add speculative execution and output buffering to its applications. This module was originally available in the linux 2.6.32 PV-OPS tree, used as dom0 for Xen. For more information, please refer to http://nss.cs.ubc.ca/remus/ and http://wiki.xensource.com/xenwiki/Remus Changes in V3: * Removed debug output (printk) on queue overflow * Added TCQ_PLUG_RELEASE_INDEFINITE - that allows the user to use this qdisc, for simple plug/unplug operations. * Use of packet counts instead of pointers to keep track of the buffers in the queue. Signed-off-by: Shriram Rajagopalan <rshriram@cs.ubc.ca> Signed-off-by: Brendan Cully <brendan@cs.ubc.ca> [author of the code in the linux 2.6.32 pvops tree] Signed-off-by: David S. Miller <davem@davemloft.net>
2012-02-06net: Make qdisc_skb_cb upper size bound explicit.David S. Miller4-9/+5
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 <davem@davemloft.net>
2012-02-02cgroup: remove cgroup_subsys argument from callbacksLi Zefan1-6/+4
The argument is not used at all, and it's not necessary, because a specific callback handler of course knows which subsys it belongs to. Now only ->pupulate() takes this argument, because the handlers of this callback always call cgroup_add_file()/cgroup_add_files(). So we reduce a few lines of code, though the shrinking of object size is minimal. 16 files changed, 113 insertions(+), 162 deletions(-) text data bss dec hex filename 5486240 656987 7039960 13183187 c928d3 vmlinux.o.orig 5486170 656987 7039960 13183117 c9288d vmlinux.o Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2012-01-22netem: Fix off-by-one bug in reorderingVijay Subramanian1-1/+1
With netem reordering, a gap of N is supposed to reorder every Nth packet with given reorder probability. However, the code currently skips N packets and reorders every (N+1)th packet. Signed-off-by: Vijay Subramanian <subramanian.vijay@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-12net_sched: sfq: add optional RED on top of SFQEric Dumazet1-16/+130
Adds an optional Random Early Detection on each SFQ flow queue. Traditional SFQ limits count of packets, while RED permits to also control number of bytes per flow, and adds ECN capability as well. 1) We dont handle the idle time management in this RED implementation, since each 'new flow' begins with a null qavg. We really want to address backlogged flows. 2) if headdrop is selected, we try to ecn mark first packet instead of currently enqueued packet. This gives faster feedback for tcp flows compared to traditional RED [ marking the last packet in queue ] Example of use : tc qdisc add dev $DEV parent 1:1 handle 10: est 1sec 4sec sfq \ limit 3000 headdrop flows 512 divisor 16384 \ redflowlimit 100000 min 8000 max 60000 probability 0.20 ecn qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 ewma 6 min 8000b max 60000b probability 0.2 ecn prob_mark 0 prob_mark_head 4876 prob_drop 6131 forced_mark 0 forced_mark_head 0 forced_drop 0 Sent 1175211782 bytes 777537 pkt (dropped 6131, overlimits 11007 requeues 0) rate 99483Kbit 8219pps backlog 689392b 456p requeues 0 In this test, with 64 netperf TCP_STREAM sessions, 50% using ECN enabled flows, we can see number of packets CE marked is smaller than number of drops (for non ECN flows) If same test is run, without RED, we can check backlog is much bigger. qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 Sent 1148683617 bytes 795006 pkt (dropped 0, overlimits 0 requeues 0) rate 98429Kbit 8521pps backlog 1221290b 841p requeues 0 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Stephen Hemminger <shemminger@vyatta.com> CC: Dave Taht <dave.taht@gmail.com> Tested-by: Dave Taht <dave.taht@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-05net_sched: red: split red_parms into parms and varsEric Dumazet3-52/+62
This patch splits the red_parms structure into two components. One holding the RED 'constant' parameters, and one containing the variables. This permits a size reduction of GRED qdisc, and is a preliminary step to add an optional RED unit to SFQ. SFQRED will have a single red_parms structure shared by all flows, and a private red_vars per flow. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Dave Taht <dave.taht@gmail.com> CC: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-05net_sched: sfq: extend limitsEric Dumazet1-58/+117
SFQ as implemented in Linux is very limited, with at most 127 flows and limit of 127 packets. [ So if 127 flows are active, we have one packet per flow ] This patch brings to SFQ following features to cope with modern needs. - Ability to specify a smaller per flow limit of inflight packets. (default value being at 127 packets) - Ability to have up to 65408 active flows (instead of 127) - Ability to have head drops instead of tail drops (to drop old packets from a flow) Example of use : No more than 20 packets per flow, max 8000 flows, max 20000 packets in SFQ qdisc, hash table of 65536 slots. tc qdisc add ... sfq \ flows 8000 \ depth 20 \ headdrop \ limit 20000 \ divisor 65536 Ram usage : 2 bytes per hash table entry (instead of previous 1 byte/entry) 32 bytes per flow on 64bit arches, instead of 384 for QFQ, so much better cache hit ratio. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Dave Taht <dave.taht@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-05net_sched: Bug in netem reorderingHagen Paul Pfeifer1-2/+2
Not now, but it looks you are correct. q->qdisc is NULL until another additional qdisc is attached (beside tfifo). See 50612537e9ab2969312. The following patch should work. From: Hagen Paul Pfeifer <hagen@jauu.net> netem: catch NULL pointer by updating the real qdisc statistic Reported-by: Vijay Subramanian <subramanian.vijay@gmail.com> Signed-off-by: Hagen Paul Pfeifer <hagen@jauu.net> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-04Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-2/+2
2012-01-04net_sched: sfq: always randomize hash perturbationEric Dumazet1-6/+6
SFQ q->perturbation is used in sfq_hash() as an input to Jenkins hash. We currently randomize this 32bit value only if a perturbation timer is setup. Its much better to always initialize it to defeat attackers, or else they can predict very well what kind of packets they have to forge to hit a particular flow. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-04net_sched: sfq: fix mem alloc error recoveryEric Dumazet1-19/+33
Since commit 817fb15dfd98 (net_sched: sfq: allow divisor to be a parameter), we can leave perturbation timer armed if a memory allocation error aborts sfq_init(). Memory containing active struct timer_list is freed and kernel can crash. Call sfq_destroy() from sfq_init() to properly dismantle qdisc. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-03net_sched: qdisc_alloc_handle() can be too slowEric Dumazet1-5/+9
When trying to allocate ~32768 qdiscs using autohandle mechanism, we can fill the space managed by kernel (handles in [8000-FFFF]:0000 range) But O(N^2) qdisc_alloc_handle() loops 0x10000 times instead of 0x8000 time tc add qdisc add dev eth0 parent 10:7fff pfifo limit 10 RTNETLINK answers: Cannot allocate memory real 1m54.826s user 0m0.000s sys 0m0.004s INFO: rcu_sched_state detected stall on CPU 0 (t=60000 jiffies) Half number of loops, and add a cond_resched() call. We hold rtnl at this point. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Dave Taht <dave.taht@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-03sch_qfq: accurate wsum handlingEric Dumazet1-8/+9
We can underestimate q->wsum in case of "tc class replace ... qfq" and/or qdisc_create_dflt() error. wsum is not really used in fast path, only at qfq qdisc/class setup, to catch user error. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-03sch_qfq: fix overflow in qfq_update_start()Eric Dumazet1-2/+2
grp->slot_shift is between 22 and 41, so using 32bit wide variables is probably a typo. This could explain QFQ hangs Dave reported to me, after 2^23 packets ? (23 = 64 - 41) Reported-by: Dave Taht <dave.taht@gmail.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Stephen Hemminger <shemminger@vyatta.com> CC: Dave Taht <dave.taht@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-03sch_sfq: dont put new flow at the end of flowsEric Dumazet1-1/+1
SFQ enqueue algo puts a new flow _behind_ all pre-existing flows in the circular list. In fact this is probably an old SFQ implementation bug. 100 Mbits = ~8333 full frames per second, or ~8 frames per ms. With 50 flows, it means your "new flow" will have to wait 50 packets being sent before its own packet. Thats the ~6ms. We certainly can change SFQ to give a priority advantage to new flows, so that next dequeued packet is taken from a new flow, not an old one. Reported-by: Dave Taht <dave.taht@gmail.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-30netem: fix classful handlingEric Dumazet1-121/+81
Commit 10f6dfcfde (Revert "sch_netem: Remove classful functionality") reintroduced classful functionality to netem, but broke basic netem behavior : netem uses an t(ime)fifo queue, and store timestamps in skb->cb[] If qdisc is changed, time constraints are not respected and other qdisc can destroy skb->cb[] and block netem at dequeue time. Fix this by always using internal tfifo, and optionally attach a child qdisc to netem (or a tree of qdiscs) Example of use : DEV=eth3 tc qdisc del dev $DEV root tc qdisc add dev $DEV root handle 30: est 1sec 8sec netem delay 20ms 10ms tc qdisc add dev $DEV handle 40:0 parent 30:0 tbf \ burst 20480 limit 20480 mtu 1514 rate 32000bps qdisc netem 30: root refcnt 18 limit 1000 delay 20.0ms 10.0ms Sent 190792 bytes 413 pkt (dropped 0, overlimits 0 requeues 0) rate 18416bit 3pps backlog 0b 0p requeues 0 qdisc tbf 40: parent 30: rate 256000bit burst 20Kb/8 mpu 0b lat 0us Sent 190792 bytes 413 pkt (dropped 6, overlimits 10 requeues 0) backlog 0b 5p requeues 0 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-30Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-3/+4
2011-12-29sch_tbf: report backlog informationEric Dumazet1-0/+1
Provide child qdisc backlog (byte count) information so that "tc -s qdisc" can report it to user. qdisc netem 30: root refcnt 18 limit 1000 delay 20.0ms 10.0ms Sent 948517 bytes 898 pkt (dropped 0, overlimits 0 requeues 1) rate 175056bit 16pps backlog 114b 1p requeues 1 qdisc tbf 40: parent 30: rate 256000bit burst 20Kb/8 mpu 0b lat 0us Sent 948517 bytes 898 pkt (dropped 15, overlimits 611 requeues 0) backlog 18168b 12p requeues 0 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-24netem: dont call vfree() under spinlock and BH disabledEric Dumazet1-3/+4
commit 6373a9a286 (netem: use vmalloc for distribution table) added a regression, since vfree() is called while holding a spinlock and BH being disabled. Fix this by doing the pointers swap in critical section, and freeing after spinlock release. Also add __GFP_NOWARN to the kmalloc() try, since we fallback to vmalloc(). 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>
2011-12-23Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-1/+1
Conflicts: net/bluetooth/l2cap_core.c Just two overlapping changes, one added an initialization of a local variable, and another change added a new local variable. Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-23netem: loss model API sizesstephen hemminger1-3/+3
The new netem loss model is configured with nested netlink messages. This code is being overly strict about sizes, and is easily confused by padding (or possible future expansion). Also message for gemodel is incorrect. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-23sch_hfsc: report backlog informationEric Dumazet1-0/+10
Add backlog (byte count) information in hfsc classes and qdisc, so that "tc -s" can report it to user, instead of 0 values : qdisc hfsc 1: root refcnt 6 default 20 Sent 45141660 bytes 30545 pkt (dropped 0, overlimits 91751 requeues 0) rate 1492Kbit 126pps backlog 103226b 74p requeues 0 ... class hfsc 1:20 parent 1:1 leaf 1201: rt m1 0bit d 0us m2 400000bit ls m1 0bit d 0us m2 200000bit Sent 49534912 bytes 33519 pkt (dropped 0, overlimits 0 requeues 0) backlog 81822b 56p requeues 0 period 23 work 49451576 bytes rtwork 13277552 bytes level 0 ... Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: John A. Sullivan III <jsullivan@opensourcedevel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-22mqprio: Avoid panic if no options are providedThomas Graf1-1/+1
Userspace may not provide TCA_OPTIONS, in fact tc currently does so not do so if no arguments are specified on the command line. Return EINVAL instead of panicing. Signed-off-by: Thomas Graf <tgraf@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-21sch_sfq: rehash queues in perturb timerEric Dumazet1-6/+81
A known Out Of Order (OOO) problem hurts SFQ when timer changes perturbation value, since all new packets delivered to SFQ enqueue might end on different slots than previous in-flight packets. With round robin delivery, we can thus deliver packets in a different order. Since SFQ is limited to small amount of in-flight packets, we can rehash packets so that this OOO problem is fixed. This rehashing is performed only if internal flow classifier is in use. We now store in skb->cb[] the "struct flow_keys" so that we dont call skb_flow_dissect() again while rehashing. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-16sch_gred: prefer GFP_KERNEL allocationsEric Dumazet1-7/+11
In control path, its better to use GFP_KERNEL allocations where possible. Before taking qdisc spinlock, we preallocate memory just in case we'll need it in gred_change_vq() This is a followup to commit 3f1e6d3fd37b (sch_gred: should not use GFP_KERNEL while holding a spinlock) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-16Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-1/+1
Conflicts: drivers/net/ethernet/freescale/fsl_pq_mdio.c net/batman-adv/translation-table.c net/ipv6/route.c
2011-12-14cls_flow: remove one dynamic arrayEric Dumazet1-1/+1
Its better to use a predefined size for this small automatic variable. Removes a sparse error as well : net/sched/cls_flow.c:288:13: error: bad constant expression Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-12netem: add cell concept to simulate special MAC behaviorHagen Paul Pfeifer1-4/+29
This extension can be used to simulate special link layer characteristics. Simulate because packet data is not modified, only the calculation base is changed to delay a packet based on the original packet size and artificial cell information. packet_overhead can be used to simulate a link layer header compression scheme (e.g. set packet_overhead to -20) or with a positive packet_overhead value an additional MAC header can be simulated. It is also possible to "replace" the 14 byte Ethernet header with something else. cell_size and cell_overhead can be used to simulate link layer schemes, based on cells, like some TDMA schemes. Another application area are MAC schemes using a link layer fragmentation with a (small) header each. Cell size is the maximum amount of data bytes within one cell. Cell overhead is an additional variable to change the per-cell-overhead (e.g. 5 byte header per fragment). Example (5 kbit/s, 20 byte per packet overhead, cell-size 100 byte, per cell overhead 5 byte): tc qdisc add dev eth0 root netem rate 5kbit 20 100 5 Signed-off-by: Hagen Paul Pfeifer <hagen@jauu.net> Signed-off-by: Florian Westphal <fw@strlen.de> Acked-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-12sch_gred: should not use GFP_KERNEL while holding a spinlockEric Dumazet1-1/+1
gred_change_vq() is called under sch_tree_lock(sch). This means a spinlock is held, and we are not allowed to sleep in this context. We might pre-allocate memory using GFP_KERNEL before taking spinlock, but this is not suitable for stable material. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-09sch_red: generalize accurate MAX_P support to RED/GRED/CHOKEEric Dumazet3-7/+32
Now RED uses a Q0.32 number to store max_p (max probability), allow RED/GRED/CHOKE to use/report full resolution at config/dump time. Old tc binaries are non aware of new attributes, and still set/get Plog. New tc binary set/get both Plog and max_p for backward compatibility, they display "probability value" if they get max_p from new kernels. # tc -d qdisc show dev ... ... qdisc red 10: parent 1:1 limit 360Kb min 30Kb max 90Kb ecn ewma 5 probability 0.09 Scell_log 15 Make sure we avoid potential divides by 0 in reciprocal_value(), if (max_th - min_th) is big. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-08sch_red: Adaptative RED AQMEric Dumazet1-0/+21
Adaptative RED AQM for linux, based on paper from Sally FLoyd, Ramakrishna Gummadi, and Scott Shenker, August 2001 : http://icir.org/floyd/papers/adaptiveRed.pdf Goal of Adaptative RED is to make max_p a dynamic value between 1% and 50% to reach the target average queue : (max_th - min_th) / 2 Every 500 ms: if (avg > target and max_p <= 0.5) increase max_p : max_p += alpha; else if (avg < target and max_p >= 0.01) decrease max_p : max_p *= beta; target :[min_th + 0.4*(min_th - max_th), min_th + 0.6*(min_th - max_th)]. alpha : min(0.01, max_p / 4) beta : 0.9 max_P is a Q0.32 fixed point number (unsigned, with 32 bits mantissa) Changes against our RED implementation are : max_p is no longer a negative power of two (1/(2^Plog)), but a Q0.32 fixed point number, to allow full range described in Adatative paper. To deliver a random number, we now use a reciprocal divide (thats really a multiply), but this operation is done once per marked/droped packet when in RED_BETWEEN_TRESH window, so added cost (compared to previous AND operation) is near zero. dump operation gives current max_p value in a new TCA_RED_MAX_P attribute. Example on a 10Mbit link : tc qdisc add dev $DEV parent 1:1 handle 10: est 1sec 8sec red \ limit 400000 min 30000 max 90000 avpkt 1000 \ burst 55 ecn adaptative bandwidth 10Mbit # tc -s -d qdisc show dev eth3 ... qdisc red 10: parent 1:1 limit 400000b min 30000b max 90000b ecn adaptative ewma 5 max_p=0.113335 Scell_log 15 Sent 50414282 bytes 34504 pkt (dropped 35, overlimits 1392 requeues 0) rate 9749Kbit 831pps backlog 72056b 16p requeues 0 marked 1357 early 35 pdrop 0 other 0 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>