The node keepalive interval is recalculated at each timer expiration
to catch any changes in the link tolerance, and stored in a field in
struct tipc_node. We use jiffies as unit for the stored value.

This is suboptimal, because it makes the calculation unnecessary
complex, including two unit conversions. The conversions also lead to
a rounding error that causes the link "abort limit" to be 3 in the
normal case, instead of 4, as intended. This again leads to unnecessary
link resets when the network is pushed close to its limit, e.g., in an
environment with hundreds of nodes or namesapces.

In this commit, we do instead let the keepalive value be calculated and
stored in milliseconds, so that there is only one conversion and the
rounding error is eliminated.

We also remove a redundant "keepalive" field in struct tipc_link. This
is remnant from the previous implementation.
Acked-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

commit 88e8ac70 ("tipc: reduce transmission rate of reset messages
when link is down") revealed a flaw in the node FSM, as defined in
the log of commit 66996b6c ("tipc: extend node FSM").

We see the following scenario:
1: Node B receives a RESET message from node A before its link endpoint
   is fully up, i.e., the node FSM is in state SELF_UP_PEER_COMING. This
   event will not change the node FSM state, but the (distinct) link FSM
   will move to state RESETTING.
2: As an effect of the previous event, the local endpoint on B will
   declare node A lost, and post the event SELF_DOWN to the its node
   FSM. This moves the FSM state to SELF_DOWN_PEER_LEAVING, meaning
   that no messages will be accepted from A until it receives another
   RESET message that confirms that A's endpoint has been reset. This
   is  wasteful, since we know this as a fact already from the first
   received RESET, but worse is that the link instance's FSM has not
   wasted this information, but instead moved on to state ESTABLISHING,
   meaning that it repeatedly sends out ACTIVATE messages to the reset
   peer A.
3: Node A will receive one of the ACTIVATE messages, move its link FSM
   to state ESTABLISHED, and start repeatedly sending out STATE messages
   to node B.
4: Node B will consistently drop these messages, since it can only accept
   accept a RESET according to its node FSM.
5: After four lost STATE messages node A will reset its link and start
   repeatedly sending out RESET messages to B.
6: Because of the reduced send rate for RESET messages, it is very
   likely that A will receive an ACTIVATE (which is sent out at a much
   higher frequency) before it gets the chance to send a RESET, and A
   may hence quickly move back to state ESTABLISHED and continue sending
   out STATE messages, which will again be dropped by B.
7: GOTO 5.
8: After having repeated the cycle 5-7 a number of times, node A will
   by chance get in between with sending a RESET, and the situation is
   resolved.

Unfortunately, we have seen that it may take a substantial amount of
time before this vicious loop is broken, sometimes in the order of
minutes.

We correct this by making a small correction to the node FSM: When a
node in state SELF_UP_PEER_COMING receives a SELF_DOWN event, it now
moves directly back to state SELF_DOWN_PEER_DOWN, instead of as now
SELF_DOWN_PEER_LEAVING. This is logically consistent, since we don't
need to wait for RESET confirmation from of an endpoint that we alread
know has been reset. It also means that node B in the scenario above
will not be dropping incoming STATE messages, and the link can come up
immediately.

Finally, a symmetry comparison reveals that the  FSM has a similar
error when receiving the event PEER_DOWN in state PEER_UP_SELF_COMING.
Instead of moving to PERR_DOWN_SELF_LEAVING, it should move directly
to SELF_DOWN_PEER_DOWN. Although we have never seen any negative effect
of this logical error, we choose fix this one, too.

The node FSM looks as follows after those changes:

                           +----------------------------------------+
                           |                           PEER_DOWN_EVT|
                           |                                        |
  +------------------------+----------------+                       |
  |SELF_DOWN_EVT           |                |                       |
  |                        |                |                       |
  |              +-----------+          +-----------+               |
  |              |NODE_      |          |NODE_      |               |
  |   +----------|FAILINGOVER|<---------|SYNCHING   |-----------+   |
  |   |SELF_     +-----------+ FAILOVER_+-----------+   PEER_   |   |
  |   |DOWN_EVT   |          A BEGIN_EVT  A         |   DOWN_EVT|   |
  |   |           |          |            |         |           |   |
  |   |           |          |            |         |           |   |
  |   |           |FAILOVER_ |FAILOVER_   |SYNCH_   |SYNCH_     |   |
  |   |           |END_EVT   |BEGIN_EVT   |BEGIN_EVT|END_EVT    |   |
  |   |           |          |            |         |           |   |
  |   |           |          |            |         |           |   |
  |   |           |         +--------------+        |           |   |
  |   |           +-------->|   SELF_UP_   |<-------+           |   |
  |   |   +-----------------|   PEER_UP    |----------------+   |   |
  |   |   |SELF_DOWN_EVT    +--------------+   PEER_DOWN_EVT|   |   |
  |   |   |                    A        A                   |   |   |
  |   |   |                    |        |                   |   |   |
  |   |   |         PEER_UP_EVT|        |SELF_UP_EVT        |   |   |
  |   |   |                    |        |                   |   |   |
  V   V   V                    |        |                   V   V   V
+------------+       +-----------+    +-----------+       +------------+
|SELF_DOWN_  |       |SELF_UP_   |    |PEER_UP_   |       |PEER_DOWN   |
|PEER_LEAVING|       |PEER_COMING|    |SELF_COMING|       |SELF_LEAVING|
+------------+       +-----------+    +-----------+       +------------+
       |               |       A        A       |                |
       |               |       |        |       |                |
       |       SELF_   |       |SELF_   |PEER_  |PEER_           |
       |       DOWN_EVT|       |UP_EVT  |UP_EVT |DOWN_EVT        |
       |               |       |        |       |                |
       |               |       |        |       |                |
       |               |    +--------------+    |                |
       |PEER_DOWN_EVT  +--->|  SELF_DOWN_  |<---+   SELF_DOWN_EVT|
       +------------------->|  PEER_DOWN   |<--------------------+
                            +--------------+
Acked-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Florian Fainelli says:

====================
net: dsa: misc improvements

This patch series builds on top of Andrew's "New DSA bind, switches as devices"
patch set and does the following:

- add a few helper functions/goodies for net/dsa/dsa2.c to be as close as possible
  from net/dsa/dsa.c in terms of what drivers can expect, in particular the slave
  MDIO bus and the enabled_port_mask and phy_mii_mask

- fix the CPU port ethtools ops to work in a multiple tree setup since we can
  no longer assume a single tree is supported

- make the bcm_sf2 driver register its own MDIO bus, yet assign it to
  ds->slave_mii_bus for everything to work in net/dsa/slave.c wrt. PHY probing,
  this is a tad cleaner than what we have now

Changes in v2:

Most of the previous patches have been dropped to just keep the relevant ones
now.

Changes in v3:
- split the addition of the slave MII bus as a separate patch
- properly unwind all operations at the right place and right time (ethtool ops,
  slave MDIO bus
- fixed a few typos here and there

Changes in v4:
- removed superfluous dst agrument to dsa_cpu_port_ethtool_{setup,restore}
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Register a slave MDIO bus which allows us to divert problematic
read/writes towards conflicting pseudo-PHY address (30). Do no longer
rely on DSA's slave_mii_bus, but instead provide our own implementation
which offers more flexibility as to what to do, and when to register it.

We need to register it by the time we are able to get access to our
memory mapped registers, which is not until drv->setup() time. In order
to avoid forward declarations, we need to re-order the function bodies a
bit.
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Reviewed-by: NVivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now that we can properly support multiple distinct trees in the system,
using a global variable: dsa_cpu_port_ethtool_ops is getting clobbered
as soon as the second switch tree gets probed, and we don't want that.

We need to move this to be dynamically allocated, and since we can't
really be comparing addresses anymore to determine first time
initialization versus any other times, just move this to dsa.c and
dsa2.c where the remainder of the dst/ds initialization happens.

The operations teardown restores the master netdev's ethtool_ops to its
original ethtool_ops pointer (typically within the Ethernet driver)
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add a helper function: dsa_cpu_port_ethtool_init() which initializes a
custom ethtool_ops structure with custom DSA ethtool operations for CPU
ports. This is a preliminary change to move the initialization outside
of net/dsa/slave.c.
Reviewed-by: NVivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Mimic what net/dsa/dsa.c does and provide a slave MII bus by default
which will be created if the driver implements a phy_read method.
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Reviewed-by: NVivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Some drivers rely on these two bitmasks to contain the correct values
for them to successfully probe and initialize at drv->setup() time,
calculate correct values to put in both masks as early as possible in
dsa_get_ports_dn().
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In case we have multiples trees and switches with the same index, we
need to add another discriminating id: the switch tree.
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Reviewed-by: NVivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

"make htmldocs" complains otherwise:

.//net/core/gen_stats.c:168: warning: No description found for parameter 'running'
.//include/linux/netdevice.h:1867: warning: No description found for parameter 'qdisc_running_key'

Fixes: f9eb8aea ("net_sched: transform qdisc running bit into a seqcount")
Fixes: edb09eb1 ("net: sched: do not acquire qdisc spinlock in qdisc/class stats dump")
Signed-off-by: NEric Dumazet <edumazet@google.com>
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When in kdump kernel, reduce memory usage by only using a single Queue
Set for multiqueue devices. So make netif_get_num_default_rss_queues()
return one, when in kdump kernel.
Signed-off-by: NHariprasad Shenai <hariprasad@chelsio.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Sudarsana Reddy Kalluru says:

====================
qed/qede support for dcbnl.

This series adds the dcbnl functionality to the driver. Patch (1) adds
the qed infrastucture for querying/configuring the dcbx parameters.
Patch (2) adds the qed infrastructure for dcbnl APIs. And patch (3)
adds the qede support for dcbnl.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds the interfaces for ieee/cee dcbnl callbacks and registers
them with the kernel.
Signed-off-by: NSudarsana Reddy Kalluru <sudarsana.kalluru@qlogic.com>
Signed-off-by: NYuval Mintz <Yuval.Mintz@qlogic.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds the implementation for both cee/ieee dcbnl callbacks by
using the qed query/config APIs.
Signed-off-by: NSudarsana Reddy Kalluru <sudarsana.kalluru@qlogic.com>
Signed-off-by: NYuval Mintz <Yuval.Mintz@qlogic.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Query API reads the dcbx data from the device shared memory and return it
to the caller. The config API configures the user provided dcbx values on
the device, and initiates the dcbx negotiation with the peer.
Signed-off-by: NSudarsana Reddy Kalluru <sudarsana.kalluru@qlogic.com>
Signed-off-by: NYuval Mintz <Yuval.Mintz@qlogic.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The CONFIG_ prefix should only be used for options which
can be configured through Kconfig and not for guarding headers.
Signed-off-by: NAndreas Ziegler <andreas.ziegler@fau.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The CONFIG_ prefix should only be used for options which
can be configured through Kconfig and not for guarding headers.
Signed-off-by: NAndreas Ziegler <andreas.ziegler@fau.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When setting up ILA in a router we noticed that the the encapsulation
is invoked twice: once in the route input path and again upon route
output. To resolve this we add a flag set_csum_neutral for the
ila_update_ipv6_locator. If this flag is set and the checksum
neutral bit is also set we assume that checksum-neutral translation
has already been performed and take no further action. The
flag is set only in ila_output path. The flag is not set for ila_input and
ila_xlat.

Tested:

Used 3 netns to set to emulate a router and two hosts. The router
translates SIR addresses between the two destinations in other two netns.
Verified ping and netperf are functional.
Signed-off-by: NTom Herbert <tom@herbertland.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

RFC 5961 advises to only accept RST packets containing a seq number
matching the next expected seq number instead of the whole receive
window in order to avoid spoofing attacks.

However, this situation is not optimal in the case SACK is in use at the
time the RST is sent. I recently run into a scenario in which packet
losses were high while uploading data to a server, and userspace was
willing to frequently terminate connections by sending a RST. In
this case, the ACK sent on the receiver side (rcv_nxt) is frozen waiting
for a lost packet retransmission and SACK blocks are used to let the
client continue uploading data. At some point later on, the client sends
the RST (snd_nxt), which matches the next expected seq number of the
right-most SACK block on the receiver side which is going forward
receiving data.

In this scenario, as RFC 5961 defines, the RST SEQ doesn't match the
frozen main ACK at receiver side and thus gets dropped and a challenge
ACK is sent, which gets usually lost due to network conditions. The main
consequence is that the connection stays alive for a while even if it
made sense to accept the RST. This can get really bad if lots of
connections like this one are created in few seconds, allocating all the
resources of the server easily.

For security reasons, not all SACK blocks are checked (there could be a
big amount of SACK blocks => acceptable SEQ numbers). Furthermore, it
wouldn't make sense to check for RST in blocks other than the right-most
received one because the sender is not expected to be sending new data
after the RST. For simplicity, only up to the 4 most recently updated
SACK blocks (selective_acks[4] field) are compared to find the
right-most block, as usually those are the ones with bigger probability
to contain it.

This patch was tested in a 3.18 kernel and probed to improve the
situation in the scenario described above.
Signed-off-by: NPau Espin Pedrol <pau.espin@tessares.net>
Acked-by: NEric Dumazet <edumazet@google.com>
Acked-by: NNeal Cardwell <ncardwell@google.com>
Tested-by: NNeal Cardwell <ncardwell@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In the current code "ent_per_page" could be more than "conn_num" making
"conn_num" negative after the subtraction.  In the next iteration
through the loop then the negative is treated as a very high positive
meaning we don't put a limit on "ent_num".  It could lead to memory
corruption.

Fixes: dbb799c3 ('qed: Initialize hardware for new protocols')
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Acked-by: NYuval Mintz <Yuval.Mintz@qlogic.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

David Ahern says:

====================
net: vrf: Add support for local traffic to local addresses

Add support for locally originated traffic to VRF-local addresses,
be it addresses on enslaved devices or addresses on the VRF device:

$ ip addr show dev red
33: red: <NOARP,MASTER,UP,LOWER_UP> mtu 65536 qdisc pfifo_fast state UP group default qlen 1000
    link/ether be:00:53:b5:e4:25 brd ff:ff:ff:ff:ff:ff
    inet 1.1.1.1/32 scope global red
       valid_lft forever preferred_lft forever
    inet6 1111:1::1/128 scope global
       valid_lft forever preferred_lft forever

$ ip addr show dev eth1
3: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master red state UP group default qlen 1000
    link/ether 02:e0:f9:79:34:bd brd ff:ff:ff:ff:ff:ff
    inet 10.100.1.1/24 brd 10.100.1.255 scope global eth1
       valid_lft forever preferred_lft forever
    inet6 2100:1::1/120 scope global
       valid_lft forever preferred_lft forever
    inet6 fe80::e0:f9ff:fe79:34bd/64 scope link
       valid_lft forever preferred_lft forever

$ ping -c1 -I red 10.100.1.1
    ping: Warning: source address might be selected on device other than red.
    PING 10.100.1.1 (10.100.1.1) from 10.100.1.1 red: 56(84) bytes of data.
    64 bytes from 10.100.1.1: icmp_seq=1 ttl=64 time=0.057 ms

$ ping -c1 -I red 1.1.1.1
PING 1.1.1.1 (1.1.1.1) from 1.1.1.1 red: 56(84) bytes of data.
64 bytes from 1.1.1.1: icmp_seq=1 ttl=64 time=0.136 ms

--- 1.1.1.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.136/0.136/0.136/0.000 ms

$ ping6 -c1 -I red  2100:1::1
ping6: Warning: source address might be selected on device other than red.
PING 2100:1::1(2100:1::1) from 2100:1::1 red: 56 data bytes
64 bytes from 2100:1::1: icmp_seq=1 ttl=64 time=0.167 ms

--- 2100:1::1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.167/0.167/0.167/0.000 ms

$ ping6 -c1 -I red 1111::1
PING 1111::1(1111::1) from 1111:1::1 red: 56 data bytes
64 bytes from 1111::1: icmp_seq=1 ttl=64 time=0.187 ms

--- 1111::1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.187/0.187/0.187/0.000 ms

This change also enables use of loopback address on the VRF device:
$ ip addr add dev red 127.0.0.1/8

$ ping -c1 -I red 127.0.0.1
PING 127.0.0.1 (127.0.0.1) from 127.0.0.1 red: 56(84) bytes of data.
64 bytes from 127.0.0.1: icmp_seq=1 ttl=64 time=0.058 ms
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add support for locally originated traffic to VRF-local IPv6 addresses.
Similar to IPv4 a local dst is set on the skb and the packet is
reinserted with a call to netif_rx. With this patch, ping, tcp and udp
packets to a local IPv6 address are successfully routed:

    $ ip addr show dev eth1
    4: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master red state UP group default qlen 1000
        link/ether 02:e0:f9:1c:b9:74 brd ff:ff:ff:ff:ff:ff
        inet 10.100.1.1/24 brd 10.100.1.255 scope global eth1
           valid_lft forever preferred_lft forever
        inet6 2100:1::1/120 scope global
           valid_lft forever preferred_lft forever
        inet6 fe80::e0:f9ff:fe1c:b974/64 scope link
           valid_lft forever preferred_lft forever

    $ ping6 -c1 -I red 2100:1::1
    ping6: Warning: source address might be selected on device other than red.
    PING 2100:1::1(2100:1::1) from 2100:1::1 red: 56 data bytes
    64 bytes from 2100:1::1: icmp_seq=1 ttl=64 time=0.098 ms

ip6_input is exported so the VRF driver can use it for the dst input
function. The dst_alloc function for IPv4 defaults to setting the input and
output functions; IPv6's does not. VRF does not need to duplicate the Rx path
so just export the ipv6 input function.
Signed-off-by: NDavid Ahern <dsa@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add support for locally originated traffic to VRF-local addresses. If
destination device for an skb is the loopback or VRF device then set
its dst to a local version of the VRF cached dst_entry and call netif_rx
to insert the packet onto the rx queue - similar to what is done for
loopback. This patch handles IPv4 support; follow on patch handles IPv6.

With this patch, ping, tcp and udp packets to a local IPv4 address are
successfully routed:

    $ ip addr show dev eth1
    4: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master red state UP group default qlen 1000
        link/ether 02:e0:f9:1c:b9:74 brd ff:ff:ff:ff:ff:ff
        inet 10.100.1.1/24 brd 10.100.1.255 scope global eth1
           valid_lft forever preferred_lft forever
        inet6 2100:1::1/120 scope global
           valid_lft forever preferred_lft forever
        inet6 fe80::e0:f9ff:fe1c:b974/64 scope link
           valid_lft forever preferred_lft forever

    $ ping -c1 -I red 10.100.1.1
    ping: Warning: source address might be selected on device other than red.
    PING 10.100.1.1 (10.100.1.1) from 10.100.1.1 red: 56(84) bytes of data.
    64 bytes from 10.100.1.1: icmp_seq=1 ttl=64 time=0.057 ms

This patch also enables use of IPv4 loopback address on the VRF device:
    $ ip addr add dev red 127.0.0.1/8

    $ ping -c1 -I red 127.0.0.1
    PING 127.0.0.1 (127.0.0.1) from 127.0.0.1 red: 56(84) bytes of data.
    64 bytes from 127.0.0.1: icmp_seq=1 ttl=64 time=0.058 ms
Signed-off-by: NDavid Ahern <dsa@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Move the stripping of the ethernet header from is_ip_tx_frame into the
ipv4 and ipv6 outbound functions and collapse vrf_send_v4_prep into
vrf_process_v4_outbound.
Signed-off-by: NDavid Ahern <dsa@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch implements direct encapsulation of IPv4 and IPv6 packets
in UDP. This is done a version "1" of GUE and as explained in I-D
draft-ietf-nvo3-gue-03.

Changes here are only in the receive path, fou with IPxIPx already
supports the transmit side. Both the normal receive path and
GRO path are modified to check for GUE version and check for
IP version in the case that GUE version is "1".

Tested:

IPIP with direct GUE encap
  1 TCP_STREAM
    4530 Mbps
  200 TCP_RR
    1297625 tps
    135/232/444 90/95/99% latencies

IP4IP6 with direct GUE encap
  1 TCP_STREAM
    4903 Mbps
  200 TCP_RR
    1184481 tps
    149/253/473 90/95/99% latencies

IP6IP6 direct GUE encap
  1 TCP_STREAM
   5146 Mbps
  200 TCP_RR
    1202879 tps
    146/251/472 90/95/99% latencies

SIT with direct GUE encap
  1 TCP_STREAM
    6111 Mbps
  200 TCP_RR
    1250337 tps
    139/241/467 90/95/99% latencies
Signed-off-by: NTom Herbert <tom@herbertland.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Eric Dumazet says:

====================
net: sched: faster stats gathering

A while back, I sent one RFC patch using lockless stats gathering
on 64bit arches.

This patch series does it more cleanly, using a seqcount.

Since qdisc/class stats are written at dequeue() time,
we can ask the dequeue to change the seqcount, so that
stats readers can avoid taking the root qdisc lock,
and instead the typical read_seqcount_{begin|retry} guarded
loop.

This does not change fast path costs, as the seqcount
increments are not more expensive than the bit manipulation,
and allows readers to not freeze the fast path anymore.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Large tc dumps (tc -s {qdisc|class} sh dev ethX) done by Google BwE host
agent [1] are problematic at scale :

For each qdisc/class found in the dump, we currently lock the root qdisc
spinlock in order to get stats. Sampling stats every 5 seconds from
thousands of HTB classes is a challenge when the root qdisc spinlock is
under high pressure. Not only the dumps take time, they also slow
down the fast path (queue/dequeue packets) by 10 % to 20 % in some cases.

An audit of existing qdiscs showed that sch_fq_codel is the only qdisc
that might need the qdisc lock in fq_codel_dump_stats() and
fq_codel_dump_class_stats()

In v2 of this patch, I now use the Qdisc running seqcount to provide
consistent reads of packets/bytes counters, regardless of 32/64 bit arches.

I also changed rate estimators to use the same infrastructure
so that they no longer need to lock root qdisc lock.

[1]
http://static.googleusercontent.com/media/research.google.com/en//pubs/archive/43838.pdfSigned-off-by: NEric Dumazet <edumazet@google.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Kevin Athey <kda@google.com>
Cc: Xiaotian Pei <xiaotian@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Instead of using a single bit (__QDISC___STATE_RUNNING)
in sch->__state, use a seqcount.

This adds lockdep support, but more importantly it will allow us
to sample qdisc/class statistics without having to grab qdisc root lock.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Sathya Perla says:

====================
be2net: patch set

Hi David, the following patch set contains three non-critical fixes that
can go into the net-next tree.

Patch 1 fixes the logic for provisioning queue pairs on VFs to take into
account the limit on number of TXQs too as in some profiles the number
of TXQs is less than that of RXQs.

Patch 2 enables WoL support from shutdown on Skyhawk.

Patch 3 enhances the logic for provisioning queue pairs on VFs on
SR-IOV over multi-partition configs. Each PF (partition) on a port has to
compute the number of RSS tables it's VFs can use.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently, we do not distribute queue resources to enable RSS for VFs
in multi-channel/partition configurations.
Fix this by having each PF(SRIOV capable) calculate it's share of the
15 RSS Policy Tables available per port before provisioning resources for
all the VFs.
This  proportional share calculation is done based on division of the
PF's MAX VFs with the Total MAX VFs on that port. It also needs to
learn about the no: of NIC PFs on the port and subtract that from
the 15 RSS Policy Tables on the port.
Signed-off-by: NSomnath Kotur <somnath.kotur@emulex.com>
Signed-off-by: NSathya Perla <sathya.perla@broadcom.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Skyhawk does support wake-up from ACPI shutdown state - S5, provided the
platform supports it (like Auxiliary power source etc). The changes listed
below are done to fix this.

1) There's no need to defer the HW configuration of WOL to be_suspend().
Remove this in be_suspend() and move it to be_set_wol() ethtool function
so it is configured directly in the context of ethtool. This automatically
takes care of the shutdown case.

2) The driver incorrectly uses WOL_CAP field in the FW response to
get_acpi_wol_cap() command, to determine if WOL is enabled. Instead the
driver must rely on the macaddr field in the response to infer WOL state.

3) In be_get_config() during init, if we find that WOL is enabled in FW,
call pci_enable_wake() to enable pmcsr.pme_en bit. This is needed to
support persistent WOL configuration provided by the FW in some platforms.

4) Remove code in be_set_wol() that writes to PCICFG_PM_CONTROL_OFFSET
to set pme_en bit; pci_enable_wake() sets that.

Fixes: 028991e4 ("Enabling Wake-on-LAN is not supported in S5 state")
Signed-off-by: NSriharsha Basavapatna <sriharsha.basavapatna@broadcom.com>
Signed-off-by: NSathya Perla <sathya.perla@broadcom.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When the PF driver provisions resources for VFs, it currently only looks
at max RSS queues available to calculate the number of VF queue pairs.
This logic breaks when there are less number of TX-queues than RSS-queues.
This patch fixes this problem by using the max-TXQs available in the
PF-pool in the calculations. As a part of this change the
be_calculate_vf_qs() routine is renamed as be_calculate_vf_res() and the
code that calculates limits on other related resources is moved here to
contain all resource calculation code inside one routine.
Signed-off-by: NSuresh Reddy <suresh.reddy@broadcom.com>
Signed-off-by: NSathya Perla <sathya.perla@broadcom.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The driver add hdlc support for Freescale QUICC Engine.
It support NMSI and TSA mode.
Signed-off-by: NZhao Qiang <qiang.zhao@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

QE has module to support TDM, some other protocols
supported by QE are based on TDM.
add a qe-tdm lib, this lib provides functions to the protocols
using TDM to configurate QE-TDM.
Signed-off-by: NZhao Qiang <qiang.zhao@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NZhao Qiang <qiang.zhao@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add tdm clock configuration in both qe clock system and ucc
fast controller.
Signed-off-by: NZhao Qiang <qiang.zhao@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Rx_sync and tx_sync are used by QE-TDM mode,
add them to struct ucc_fast_info.
Signed-off-by: NZhao Qiang <qiang.zhao@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NJamal Hadi Salim <jhs@mojatatu.com>
Acked-by: NCong Wang <xiyou.wangcong@gmail.com>

Jamal Hadi Salim says:

====================
net sched action timestamp improvements

Various aggregations of duplicated code, fixes and introduction of firstused
timestamp

v2: add const for source time info per suggestion from Cong
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NJamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>