The mirrored packets arrive at $h3 encapsulated in GRE/IPv4, with IP
address from 192.0.2.128/28 network. However the interface is configured
as a member of 192.0.2.160/28 and there's no route directing traffic
from the former network through that interface. Correspondingly, the RP
filter on the VRF rejects it.
Therefore turn off the VRF's RP filter.
Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Ido Schimmel says:
====================
mlxsw: ERSPAN: Take LACP state into consideration
Petr says:
When offloading mirror-to-gretap, mlxsw needs to preroute the path that
the encapsulated packet will take. That path may include a LAG device
above a front panel port. So far, mlxsw resolved the path to the first
up front panel slave of the LAG interface, but that only reflects
administrative state of the port. It neglects to consider whether the
port actually has a carrier, and what the LACP state is. This patch set
aims to address these problems.
Patch #1 publishes team_port_get_rcu().
Then in patch #2, a new function is introduced,
mlxsw_sp_port_dev_check(). That returns, for a given netdevice that is a
slave of a LAG device, whether that device is "txable", i.e. whether the
LAG master would send traffic through it. Since there's no good place to
put LAG-wide helpers, introduce a new header include/net/lag.h.
Finally in patch #3, fix the slave selection logic to take into
consideration whether a given slave has a carrier and whether it is
txable.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
When offloading mirror-to-gretap, mlxsw needs to preroute the path that
the encapsulated packet will take. That path may include a LAG device
above a front panel port. So far, mlxsw resolved the path to the first
up front panel slave of the LAG interface, but that only reflects
administrative state of the port. It neglects to consider whether the
port actually has a carrier, and what the LACP state is.
So instead of checking upness of the device, check carrier state and
txability.
Signed-off-by: Petr Machata <petrm@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
LAG devices (team or bond) recognize for each one of their slave devices
whether LAG traffic is going to be sent through that device. Bond calls
such devices "active", team calls them "txable". When this state
changes, a NETDEV_CHANGELOWERSTATE notification is distributed, together
with a netdev_notifier_changelowerstate_info structure that for LAG
devices includes a tx_enabled flag that refers to the new state. The
notification thus makes it possible to react to the changes in txability
in drivers.
However there's no way to query txability from the outside on demand.
That is problematic namely for mlxsw, which when resolving ERSPAN packet
path, may encounter a LAG device, and needs to determine which of the
slaves it should choose.
To that end, introduce a new function, net_lag_port_dev_txable(), which
determines whether a given slave device is "active" or
"txable" (depending on the flavor of the LAG device). That function then
dispatches to per-LAG-flavor helpers, bond_is_active_slave_dev() resp.
team_port_dev_txable().
Because there currently is no good place where net_lag_port_dev_txable()
should be added, introduce a new header file, lag.h, which should from
now on hold any logic common to both team and bond. (But keep
netif_is_lag_master() together with the rest of netif_is_*_master()
functions).
Signed-off-by: Petr Machata <petrm@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
A follow-up patch adds a new entry point, team_port_dev_txable(). Making
it an ordinary exported function would mean that any module that may
need the service in one of the supported configurations also
unconditionally needs to pull in the team module, whether or not the
user actually intends to create team interfaces.
To prevent that, team_port_dev_txable() is defined in if_team.h, and
therefore all dependencies of that function also need to be
publicly-visible.
Therefore move team_port_get_rcu() from team.c to if_team.h.
Signed-off-by: Petr Machata <petrm@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Today macvlan ignores the notification when a lower device goes
administratively down, preventing the lack of connectivity from
bubbling up.
Processing NETDEV_DOWN results in a macvlan state of LOWERLAYERDOWN
with NO-CARRIER which should be easy to interpret in userspace.
2: lower: <BROADCAST,MULTICAST> mtu 1500 qdisc mq state DOWN mode DEFAULT group default qlen 1000
3: macvlan@lower: <NO-CARRIER,BROADCAST,MULTICAST,UP,M-DOWN> mtu 1500 qdisc noqueue state LOWERLAYERDOWN mode DEFAULT group default qlen 1000
Signed-off-by: Suresh Krishnan <skrishnan@arista.com>
Signed-off-by: Travis Brown <travisb@arista.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Jon Maloy says:
====================
tipc: make link protocol more resilient
These two commits make the link ptotocol more resilient to
infrastructures with frequent packet duplication and long delays.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
In some virtual environments we observe a significant higher number of
packet reordering and delays than we have been used to traditionally.
This makes it necessary with stricter checks on incoming link protocol
messages' session number, which until now only has been validated for
RESET messages.
Since the other two message types, ACTIVATE and STATE messages also
carry this number, it is easy to extend the validation check to those
messages.
We also introduce a flag indicating if a link has a valid peer session
number or not. This eliminates the mixing of 32- and 16-bit arithmethics
we are currently using to achieve this.
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some switch infrastructures produce huge amounts of packet duplicates.
This becomes a problem if those messages are STATE/NACK protocol
messages, causing unnecessary retransmissions of already accepted
packets.
We now introduce a unique sequence number per STATE protocol message
so that duplicates can be identified and ignored. This will also be
useful when tracing such cases, and to avert replay attacks when TIPC
is encrypted.
For compatibility reasons we have to introduce a new capability flag
TIPC_LINK_PROTO_SEQNO to handle this new feature.
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Jeff Kirsher says:
====================
L2 Fwd Offload & 10GbE Intel Driver Updates 2018-07-09
This patch series is meant to allow support for the L2 forward offload, aka
MACVLAN offload without the need for using ndo_select_queue.
The existing solution currently requires that we use ndo_select_queue in
the transmit path if we want to associate specific Tx queues with a given
MACVLAN interface. In order to get away from this we need to repurpose the
tc_to_txq array and XPS pointer for the MACVLAN interface and use those as
a means of accessing the queues on the lower device. As a result we cannot
offload a device that is configured as multiqueue, however it doesn't
really make sense to configure a macvlan interfaced as being multiqueue
anyway since it doesn't really have a qdisc of its own in the first place.
The big changes in this set are:
Allow lower device to update tc_to_txq and XPS map of offloaded MACVLAN
Disable XPS for single queue devices
Replace accel_priv with sb_dev in ndo_select_queue
Add sb_dev parameter to fallback function for ndo_select_queue
Consolidated ndo_select_queue functions that appeared to be duplicates
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Congestion control algorithms, which access the rate sample
through the tcp_cong_control function, only have access to the maximum
of the send and receive interval, for cases where the acknowledgment
rate may be inaccurate due to ACK compression or decimation. Algorithms
may want to use send rates and receive rates as separate signals.
Signed-off-by: Deepti Raghavan <deeptir@mit.edu>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix action attribute size calculation function to take rcu read lock and
access act_cookie pointer with rcu dereference.
Fixes: eec94fdb04 ("net: sched: use rcu for action cookie update")
Reported-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Rahul Lakkireddy says:
====================
cxgb4: move stats fetched from firmware to debugfs
Some stats are fetched via slow firmware mailbox, which can cause
packet drops under heavy load. So, this series removes these stats
from ethtool -S and expose them via debugfs.
Patch 1 removes stats fetched via firmware from ethtool -S.
Patch 2 exposes stats removed in Patch 1 via debugfs.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Expose stats obtained from firmware via debugfs. These stats can't
be part of ethtool -S because the slow firmware mailbox can cause
packet drops under heavy load.
Signed-off-by: Rahul Lakkireddy <rahul.lakkireddy@chelsio.com>
Signed-off-by: Ganesh Goudar <ganeshgr@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When running ethtool -S, some stats are requested from firmware.
Since getting these stats via firmware mailbox is slow, some packets
get dropped under heavy load while running ethtool -S.
So, remove these stats from ethtool -S.
Signed-off-by: Rahul Lakkireddy <rahul.lakkireddy@chelsio.com>
Signed-off-by: Ganesh Goudar <ganeshgr@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The Marvell PPv2 driver uses interrupts and tasklet but does not
explicitly include linux/interrupt.h, relying on implicit includes. This
one particularly is included by chance after a long unlogical chain of
inclusions. Fix this so we do not get future build breaks.
Signed-off-by: Antoine Tenart <antoine.tenart@bootlin.com>
Signed-off-by: Antoine Tenart <antoine.tenart@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Size of csk_tbl is about 58K, which means 3rd order page allocation.
kvzalloc provides a fallback if no high order memory is available.
Signed-off-by: Jan Dakinevich <jan.dakinevich@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Variables ack_status, bcf and protocol are being assigned but are
never used hence they are redundant and can be removed.
Also declare ack_type as unsigned int rather than unsigned to clean
up a checkpatch warning.
Cleans up clang warnings:
warning: variable 'ack_status' set but not used [-Wunused-but-set-variable]
warning: variable 'bcf' set but not used [-Wunused-but-set-variable]
warning: variable 'protocol' set but not used [-Wunused-but-set-variable]
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Free params if tcf_idr_check_alloc() returned error.
Fixes: 0190c1d452 ("net: sched: atomically check-allocate action")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
congestion argument passed to t4_sge_alloc_rxq() is used
to differentiate between nic/ofld queues.
Signed-off-by: Arjun Vynipadath <arjun@chelsio.com>
Signed-off-by: Ganesh Goudar <ganeshgr@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Sabrina Dubroca says:
====================
net/ipv6: addr_gen_mode fixes
This series fixes bugs in handling of the addr_gen_mode option, mainly
related to the sysctl. A minor netlink issue was also present in the
initial commit introducing the option on a per-netdevice basis.
v2: add patch 4, requested by David Ahern during review of v1
add patch 5, missing documentation for the sysctl
patches 1, 2, 3 are unchanged
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
addr_gen_mode was introduced in without documentation, add it now.
Fixes: d35a00b8e3 ("net/ipv6: allow sysctl to change link-local address generation mode")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This aligns the addr_gen_mode sysctl with the expected behavior of the
"all" variant.
Fixes: d35a00b8e3 ("net/ipv6: allow sysctl to change link-local address generation mode")
Suggested-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
inet6_ifla6_size() is called to check how much space is needed by
inet6_fill_link_af() and inet6_fill_ifinfo(), both of which include
the IFLA_INET6_ADDR_GEN_MODE attribute. Reserve some room for it.
Fixes: bc91b0f07a ("ipv6: addrconf: implement address generation modes")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The value has already been copied from this netns's devconf_dflt, it
shouldn't be reset to the global kernel default.
Fixes: d35a00b8e3 ("net/ipv6: allow sysctl to change link-local address generation mode")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
addrconf_sysctl_addr_gen_mode() has multiple problems. First, it ignores
the errors returned by proc_dointvec().
addrconf_sysctl_addr_gen_mode() calls proc_dointvec() directly, which
writes the value to memory, and then checks if it's valid and may return
EINVAL. If a bad value is given, the value displayed when reading
net.ipv6.conf.foo.addr_gen_mode next time will be invalid. In case the
value provided by the user was valid, addrconf_dev_config() won't be
called since idev->cnf.addr_gen_mode has already been updated.
Fix this in the usual way we deal with values that need to be checked
after the proc_do*() helper has returned: define a local ctl_table and
storage, call proc_dointvec() on that temporary area, then check and
store.
addrconf_sysctl_addr_gen_mode() also writes the new value to the global
ipv6_devconf_dflt, when we're writing to some netns's default, so that
new netns will inherit the value that was set by the change occuring in
any netns. That doesn't make any sense, so let's drop this assignment.
Finally, since addr_gen_mode is a __u32, switch to proc_douintvec().
Fixes: d35a00b8e3 ("net/ipv6: allow sysctl to change link-local address generation mode")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Zahari issued tc vlan command without setting vlan_ethtype, which will
crash kernel. To avoid this, we must check tb[TCA_FLOWER_KEY_VLAN_ETH_TYPE]
is not null before use it.
Also we don't need to dump vlan_ethtype or cvlan_ethtype in this case.
Fixes: d64efd0926 ('net/sched: flower: Add supprt for matching on QinQ vlan headers')
Signed-off-by: Jianbo Liu <jianbol@mellanox.com>
Reported-by: Zahari Doychev <zahari.doychev@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Jakub Kicinski says:
====================
This series starts with two minor clean ups to test_offload.py
selftest script.
The next 11 patches extend the abilities of bpftool prog load
beyond the simple cgroup use cases. Three new parameters are
added:
- type - allows specifying program type, independent of how
code sections are named;
- map - allows reusing existing maps, instead of creating a new
map on every program load;
- dev - offload/binding to a device.
A number of changes to libbpf is required to accomplish the task.
The section - program type logic mapping is exposed. We should
probably aim to use the libbpf program section naming everywhere.
For reuse of maps we need to allow users to set FD for bpf map
object in libbpf.
Examples
Load program my_xdp.o and pin it as /sys/fs/bpf/my_xdp, for xdp
program type:
$ bpftool prog load my_xdp.o /sys/fs/bpf/my_xdp \
type xdp
As above but for offload:
$ bpftool prog load my_xdp.o /sys/fs/bpf/my_xdp \
type xdp \
dev netdevsim0
Load program my_maps.o, but for the first map reuse map id 17,
and for the map called "other_map" reuse pinned map /sys/fs/bpf/map0:
$ bpftool prog load my_maps.o /sys/fs/bpf/prog \
map idx 0 id 17 \
map name other_map pinned /sys/fs/bpf/map0
v3:
- fix return codes in patch 5;
- rename libbpf_prog_type_by_string() -> libbpf_prog_type_by_name();
- fold file path into xattr in patch 8;
- add patch 10;
- use dup3() in patch 12;
- depend on fd value in patch 12;
- close old fd in patch 12.
v2:
- add compat for reallocarray().
====================
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Add map parameter to prog load which will allow reuse of existing
maps instead of creating new ones.
We need feature detection and compat code for reallocarray, since
it's not available in many libc versions.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
More advanced applications may want to only replace programs without
destroying associated maps. Allow libbpf users to achieve that.
Instead of always creating all of the maps at load time, expose to
users an API to reconstruct the map object from already existing
map.
The map parameters are read from the kernel and replace the parameters
of the ELF map. libbpf does not restrict the map replacement, i.e.
the reused map does not have to be compatible with the ELF map
definition. We relay on the verifier for checking the compatibility
between maps and programs. The ELF map definition is completely
overwritten by the information read from the kernel, to make sure
libbpf's view of map object corresponds to the actual map.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
reallocarray() is a safer variant of realloc which checks for
multiplication overflow in case of array allocation. Since it's
not available in Glibc < 2.26 import kernel's overflow.h and
add a static inline implementation when needed. Use feature
detection to probe for existence of reallocarray.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
libbpf_strerror() depends on XSI-compliant (POSIX) version of
strerror_r(), which prevents us from using GNU-extensions in
libbpf.c, like reallocarray() or dup3(). Move error printing
code into a separate file to allow it to continue using POSIX
strerror_r().
No functional changes.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
bpf_prog_load() is a very useful helper but it doesn't give us full
flexibility of modifying the BPF objects before loading. Open code
bpf_prog_load() in bpftool so we can add extra logic in following
commits.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Similarly to bpf_prog_load() users of bpf_object__open() may need
to specify the expected program type. Program type is needed at
open to avoid the kernel version check for program types which don't
require it.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Add helper to libbpf for recognizing maps which should not have
ifindex set when program is loaded. These maps only contain
host metadata and therefore are not marked for offload, e.g.
the perf event map.
Use this helper in bpf_prog_load_xattr().
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Sometimes program section names don't match with libbpf's expectation.
In particular XDP's default section names differ between libbpf and
iproute2. Allow users to pass program type on command line. Name
the types like the libbpf expected section names.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
libbpf can guess program type based on ELF section names. As libbpf
becomes more popular its association between section name strings and
types becomes more of a standard. Allow libbpf users to use the same
logic for matching strings to types, e.g. when the string originates
from command line.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Extend the bpftool prog load command to also accept "dev"
parameter, which will allow us to load programs onto devices.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Add a new macro for printing more informative message than straight
usage() when parameters are missing, and use it for prog do_load().
Save the object and pin path argument to variables for clarity.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Currently the test only checks errors, not warnings, so save typing
and prefix the extack messages with "Error:" inside the check helper.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Trivial removal of duplicated "mode" in error message.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
The function do_test_span_vlan_dir_ips() is used for testing whether
mirrored packets are VLAN-encapsulated. But since it only considers
VLAN encapsulation, it may end up matching unmirrored ARP traffic as
well. One consequence is a rare failure of mirror_gre_vlan_bridge_1q's
test_gretap_untagged_egress. Decreasing ping cadence in mirror_test()
makes the problem easily reproducible.
Therefore tighten up the match criterion to only count those 802.1q
packets where the next header is IP.
Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Toke Høiland-Jørgensen says:
====================
sched: Add Common Applications Kept Enhanced (cake) qdisc
This patch series adds the CAKE qdisc, and has been split up to ease
review.
I have attempted to split out each configurable feature into its own patch.
The first commit adds the base shaper and packet scheduler, while
subsequent commits add the optional features. The full userspace API and
most data structures are included in this commit, but options not
understood in the base version will be ignored.
The result of applying the entire series is identical to the out of tree
version that have seen extensive testing in previous deployments, most
notably as an out of tree patch to OpenWrt. However, note that I have only
compile tested the individual patches; so the whole series should be
considered as a unit.
---
Changelog
v19:
- Rebase to current net-next.
- Don't rely on the value of sch->q.qlen to break loops; fixes possible
infinite loop on multi-queue devices.
- Don't overwrite NAT flag when setting flow mode.
v18:
- Rework classification logic in the diffserv case to always hash if
filter doesn't select a queue, and to run TC filters before
selecting the diffserv tin (allowing filter to influence this).
- Make sure we always call qdisc_watchdog_init() in cake_init(), so we
don't crash in cake_destroy().
v17:
- Rebase to newest net-next and move the conntrack callback to
nf_ct_hook
- Fix a compile error when NF_CONNTRACK is unset.
v16:
- Move conntrack lookup function into conntrack core and read it via
RCU so it is only active when the nf_conntrack module is loaded.
This avoids the module dependency on conntrack for NAT mode. Thanks
to Pablo for the idea.
v15:
- Handle ECN flags in ACK filter
v14:
- Handle seqno wraps and DSACKs in ACK filter
v13:
- Avoid ktime_t to scalar compares
- Add class dumping and basic stats
- Fail with ENOTSUPP when requesting NAT mode and conntrack is not
available.
- Parse all TCP options in ACK filter and make sure to only drop safe
ones. Also handle SACK ranges properly.
v12:
- Get rid of custom time typedefs. Use ktime_t for time and u64 for
duration instead.
v11:
- Fix overhead compensation calculation for GSO packets
- Change configured rate to be u64 (I ran out of bits before I ran out
of CPU when testing the effects of the above)
v10:
- Christmas tree gardening (fix variable declarations to be in reverse
line length order)
v9:
- Remove duplicated checks around kvfree() and just call it
unconditionally.
- Don't pass __GFP_NOWARN when allocating memory
- Move options in cake_dump() that are related to optional features to
later patches implementing the features.
- Support attaching filters to the qdisc and use the classification
result to select flow queue.
- Support overriding diffserv priority tin from skb->priority
v8:
- Remove inline keyword from function definitions
- Simplify ACK filter; remove the complex state handling to make the
logic easier to follow. This will potentially be a bit less efficient,
but I have not been able to measure a difference.
v7:
- Split up patch into a series to ease review.
- Constify the ACK filter.
v6:
- Fix 6in4 encapsulation checks in ACK filter code
- Checkpatch fixes
v5:
- Refactor ACK filter code and hopefully fix the safety issues
properly this time.
v4:
- Only split GSO packets if shaping at speeds <= 1Gbps
- Fix overhead calculation code to also work for GSO packets
- Don't re-implement kvzalloc()
- Remove local header include from out-of-tree build (fixes kbuild-bot
complaint).
- Several fixes to the ACK filter:
- Check pskb_may_pull() before deref of transport headers.
- Don't run ACK filter logic on split GSO packets
- Fix TCP sequence number compare to deal with wraparounds
v3:
- Use IS_REACHABLE() macro to fix compilation when sch_cake is
built-in and conntrack is a module.
- Switch the stats output to use nested netlink attributes instead
of a versioned struct.
- Remove GPL boilerplate.
- Fix array initialisation style.
v2:
- Fix kbuild test bot complaint
- Clean up the netlink ABI
- Fix checkpatch complaints
- A few tweaks to the behaviour of cake based on testing carried out
while writing the paper.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
At lower bandwidths, the transmission time of a single GSO segment can add
an unacceptable amount of latency due to HOL blocking. Furthermore, with a
software shaper, any tuning mechanism employed by the kernel to control the
maximum size of GSO segments is thrown off by the artificial limit on
bandwidth. For this reason, we split GSO segments into their individual
packets iff the shaper is active and configured to a bandwidth <= 1 Gbps.
Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit adds configurable overhead compensation support to the rate
shaper. With this feature, userspace can configure the actual bottleneck
link overhead and encapsulation mode used, which will be used by the shaper
to calculate the precise duration of each packet on the wire.
This feature is needed because CAKE is often deployed one or two hops
upstream of the actual bottleneck (which can be, e.g., inside a DSL or
cable modem). In this case, the link layer characteristics and overhead
reported by the kernel does not match the actual bottleneck. Being able to
set the actual values in use makes it possible to configure the shaper rate
much closer to the actual bottleneck rate (our experience shows it is
possible to get with 0.1% of the actual physical bottleneck rate), thus
keeping latency low without sacrificing bandwidth.
The overhead compensation has three tunables: A fixed per-packet overhead
size (which, if set, will be accounted from the IP packet header), a
minimum packet size (MPU) and a framing mode supporting either ATM or PTM
framing. We include a set of common keywords in TC to help users configure
the right parameters. If no overhead value is set, the value reported by
the kernel is used.
Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>
This adds support for DiffServ-based priority queueing to CAKE. If the
shaper is in use, each priority tier gets its own virtual clock, which
limits that tier's rate to a fraction of the overall shaped rate, to
discourage trying to game the priority mechanism.
CAKE defaults to a simple, three-tier mode that interprets most code points
as "best effort", but places CS1 traffic into a low-priority "bulk" tier
which is assigned 1/16 of the total rate, and a few code points indicating
latency-sensitive or control traffic (specifically TOS4, VA, EF, CS6, CS7)
into a "latency sensitive" high-priority tier, which is assigned 1/4 rate.
The other supported DiffServ modes are a 4-tier mode matching the 802.11e
precedence rules, as well as two 8-tier modes, one of which implements
strict precedence of the eight priority levels.
This commit also adds an optional DiffServ 'wash' mode, which will zero out
the DSCP fields of any packet passing through CAKE. While this can
technically be done with other mechanisms in the kernel, having the feature
available in CAKE significantly decreases configuration complexity; and the
implementation cost is low on top of the other DiffServ-handling code.
Filters and applications can set the skb->priority field to override the
DSCP-based classification into tiers. If TC_H_MAJ(skb->priority) matches
CAKE's qdisc handle, the minor number will be interpreted as a priority
tier if it is less than or equal to the number of configured priority
tiers.
Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>
When CAKE is deployed on a gateway that also performs NAT (which is a
common deployment mode), the host fairness mechanism cannot distinguish
internal hosts from each other, and so fails to work correctly.
To fix this, we add an optional NAT awareness mode, which will query the
kernel conntrack mechanism to obtain the pre-NAT addresses for each packet
and use that in the flow and host hashing.
When the shaper is enabled and the host is already performing NAT, the cost
of this lookup is negligible. However, in unlimited mode with no NAT being
performed, there is a significant CPU cost at higher bandwidths. For this
reason, the feature is turned off by default.
Cc: netfilter-devel@vger.kernel.org
Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>
This adds a global netfilter function to extract a conntrack tuple from an
skb. The function uses a new function added to nf_ct_hook, which will try
to get the tuple from skb->_nfct, and do a full lookup if that fails. This
makes it possible to use the lookup function before the skb has passed
through the conntrack init hooks (e.g., in an ingress qdisc). The tuple is
copied to the caller to avoid issues with reference counting.
The function returns false if conntrack is not loaded, allowing it to be
used without incurring a module dependency on conntrack. This is used by
the NAT mode in sch_cake.
Cc: netfilter-devel@vger.kernel.org
Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>
The ACK filter is an optional feature of CAKE which is designed to improve
performance on links with very asymmetrical rate limits. On such links
(which are unfortunately quite prevalent, especially for DSL and cable
subscribers), the downstream throughput can be limited by the number of
ACKs capable of being transmitted in the *upstream* direction.
Filtering ACKs can, in general, have adverse effects on TCP performance
because it interferes with ACK clocking (especially in slow start), and it
reduces the flow's resiliency to ACKs being dropped further along the path.
To alleviate these drawbacks, the ACK filter in CAKE tries its best to
always keep enough ACKs queued to ensure forward progress in the TCP flow
being filtered. It does this by only filtering redundant ACKs. In its
default 'conservative' mode, the filter will always keep at least two
redundant ACKs in the queue, while in 'aggressive' mode, it will filter
down to a single ACK.
The ACK filter works by inspecting the per-flow queue on every packet
enqueue. Starting at the head of the queue, the filter looks for another
eligible packet to drop (so the ACK being dropped is always closer to the
head of the queue than the packet being enqueued). An ACK is eligible only
if it ACKs *fewer* bytes than the new packet being enqueued, including any
SACK options. This prevents duplicate ACKs from being filtered, to avoid
interfering with retransmission logic. In addition, we check TCP header
options and only drop those that are known to not interfere with sender
state. In particular, packets with unknown option codes are never dropped.
In aggressive mode, an eligible packet is always dropped, while in
conservative mode, at least two ACKs are kept in the queue. Only pure ACKs
(with no data segments) are considered eligible for dropping, but when an
ACK with data segments is enqueued, this can cause another pure ACK to
become eligible for dropping.
The approach described above ensures that this ACK filter avoids most of
the drawbacks of a naive filtering mechanism that only keeps flow state but
does not inspect the queue. This is the rationale for including the ACK
filter in CAKE itself rather than as separate module (as the TC filter, for
instance).
Our performance evaluation has shown that on a 30/1 Mbps link with a
bidirectional traffic test (RRUL), turning on the ACK filter on the
upstream link improves downstream throughput by ~20% (both modes) and
upstream throughput by ~12% in conservative mode and ~40% in aggressive
mode, at the cost of ~5ms of inter-flow latency due to the increased
congestion.
In *really* pathological cases, the effect can be a lot more; for instance,
the ACK filter increases the achievable downstream throughput on a link
with 100 Kbps in the upstream direction by an order of magnitude (from ~2.5
Mbps to ~25 Mbps).
Finally, even though we consider the ACK filter to be safer than most, we
do not recommend turning it on everywhere: on more symmetrical link
bandwidths the effect is negligible at best.
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>
The ingress mode is meant to be enabled when CAKE runs downlink of the
actual bottleneck (such as on an IFB device). The mode changes the shaper
to also account dropped packets to the shaped rate, as these have already
traversed the bottleneck.
Enabling ingress mode will also tune the AQM to always keep at least two
packets queued *for each flow*. This is done by scaling the minimum queue
occupancy level that will disable the AQM by the number of active bulk
flows. The rationale for this is that retransmits are more expensive in
ingress mode, since dropped packets have to traverse the bottleneck again
when they are retransmitted; thus, being more lenient and keeping a minimum
number of packets queued will improve throughput in cases where the number
of active flows are so large that they saturate the bottleneck even at
their minimum window size.
This commit also adds a separate switch to enable ingress mode rate
autoscaling. If enabled, the autoscaling code will observe the actual
traffic rate and adjust the shaper rate to match it. This can help avoid
latency increases in the case where the actual bottleneck rate decreases
below the shaped rate. The scaling filters out spikes by an EWMA filter.
Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Petr Machata