When we added pacing to TCP, we decided to let sch_fq take care
of actual pacing.

All TCP had to do was to compute sk->pacing_rate using simple formula:

sk->pacing_rate = 2 * cwnd * mss / rtt

It works well for senders (bulk flows), but not very well for receivers
or even RPC :

cwnd on the receiver can be less than 10, rtt can be around 100ms, so we
can end up pacing ACK packets, slowing down the sender.

Really, only the sender should pace, according to its own logic.

Instead of adding a new bit in skb, or call yet another flow
dissection, we tweak skb->truesize to a small value (2), and
we instruct sch_fq to use new helper and not pace pure ack.

Note this also helps TCP small queue, as ack packets present
in qdisc/NIC do not prevent sending a data packet (RPC workload)

This helps to reduce tx completion overhead, ack packets can use regular
sock_wfree() instead of tcp_wfree() which is a bit more expensive.

This has no impact in the case packets are sent to loopback interface,
as we do not coalesce ack packets (were we would detect skb->truesize
lie)

In case netem (with a delay) is used, skb_orphan_partial() also sets
skb->truesize to 1.

This patch is a combination of two patches we used for about one year at
Google.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Herbert Xu says:

====================
rhashtable: Add iterators and use them

The first patch fixes a potential crash with nft_hash destroying
the table during a shrinking process.  While the next patch adds
rhashtable iterators to replace current manual walks used by
netlink and netfilter.  The final two patches make use of these
iterators in netlink and netfilter.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch gets rid of the manual rhashtable walk in nft_hash
which touches rhashtable internals that should not be exposed.
It does so by using the rhashtable iterator primitives.

Note that I'm leaving nft_hash_destroy alone since it's only
invoked on shutdown and it shouldn't be affected by changes
to rhashtable internals (or at least not what I'm planning to
change).
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch gets rid of the manual rhashtable walk in netlink
which touches rhashtable internals that should not be exposed.
It does so by using the rhashtable iterator primitives.

In fact the existing code was very buggy.  Some sockets weren't
shown at all while others were shown more than once.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

Some existing rhashtable users get too intimate with it by walking
the buckets directly.  This prevents us from easily changing the
internals of rhashtable.

This patch adds the helpers rhashtable_walk_init/exit/start/next/stop
which will replace these custom walkers.

They are meant to be usable for both procfs seq_file walks as well
as walking by a netlink dump.  The iterator structure should fit
inside a netlink dump cb structure, with at least one element to
spare.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

The current being_destroyed check in rhashtable_expand is not
enough since if we start a shrinking process after freeing all
elements in the table that's also going to crash.

This patch adds a being_destroyed check to the deferred worker
thread so that we bail out as soon as we take the lock.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

The functions cpsw_ale_destroy() and of_dev_put() test whether their argument
is NULL and then return immediately. Thus the test around the call
is not needed.

This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

The of_dev_put() function tests whether its argument is NULL and then
returns immediately. Thus the test around the call is not needed.

This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

Amir Vadai says:

====================
Mellanox drivers updates Feb-03-2015

This patchset introduces some small bug fixes and code cleanups in mlx4_core,
mlx4_en and mlx5_core.
I am sending it in parallel to the patchset sent by Or Gerlitz today [1] because
this is the end of the time frame for 3.20. I also checked that there are no
conflicts between those two patchsets (Or's patchset is focused on the bonding
area while this on Mellanox drivers).

The patchset was applied on top of commit 7d37d0c1 ('net: sctp: Deletion of an
unnecessary check before the function call "kfree"')

[1] - [PATCH 00/10] Add HA and LAG support to mlx4 RoCE and SRIOV services
      http://marc.info/?l=linux-netdev&m=142297582610254&w=2
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Notify users when TX vlan offload feature changed with ethtool.
Relevant command - ethtool -K <eth> txvlan on/off.
Signed-off-by: Ido Shamay <idos@mellanox.com>
Signed-off-by: Amir Vadai <amirv@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch improves memory utilization and therefore the packets rate
for special MTU's. Instead of setting the frag_stride to the maximal
hard coded frag_size, use the actual frag_size that is set according to
the MTU, when setting the stride of the last frag.
So, for example, for MTU 1600, where the frag_size of the 2nd frag is
86, the frag_size is set to 128 instead of 4096. See below:

Before:
 frag:0 - size:1536 prefix:0 stride:1536
 frag:1 - size:86 prefix:1536 stride:4096

 frag 0 allocator: - size:32768 frags:21
 frag 1 allocator: - size:32768 frags:8

After:
 frag:0 - size:1536 prefix:0 stride:1536
 frag:1 - size:86 prefix:1536 stride:128

 frag 0 allocator: - size:32768 frags:21
 frag 1 allocator: - size:32768 frags:256
Signed-off-by: Ido Shamay <idos@mellanox.com>
Signed-off-by: Amir Vadai <amirv@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

After Initialization of page_alloc, print actual allocated page
size and number of frags it contains. prints is done only when drv
message level is set on the interface.
Signed-off-by: Ido Shamay <idos@mellanox.com>
Signed-off-by: Amir Vadai <amirv@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Align the IDs in the code with the modinfo, lspci -n, etc tools outputs.
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Amir Vadai <amirv@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

We do support cache line sizes of 32 and 64 bytes without activating the
CQE stride feature. Fix a misleading print saying that these cache line
sizes aren't supported.
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Amir Vadai <amirv@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Add Initialization to struct config_dev before filling and using it.
Fix to warning:

warning: config_dev.rx_checksum_val may be used uninitialized in this function
Signed-off-by: Maor Gottlieb <maorg@mellanox.com>
Signed-off-by: Amir Vadai <amirv@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

a) Previously, mlx4_mr_rereg_write filled the MPT's start
   and length with the old MPT's values.
   Fixing the initialization to take the new start and length.

b) In addition access flags in mpt_status were initialized instead of
   status due to bad boolean operation. Fixing the operation.

c) Initialization of pd_slave caused a protection error.
   Fix - removing this initialization.

d) In resource_tracker.c: Fixing vf encoding to be one-based.

Fixes: e630664c ('mlx4_core: Add helper functions to support MR re-registration')
Signed-off-by: Maor Gottlieb <maorg@mellanox.com>
Signed-off-by: Amir Vadai <amirv@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Or Gerlitz says:

====================
Add HA and LAG support to mlx4 RoCE and SRIOV services

This series takes advanges of bonding mlx4 Ethernet devices to support
a model of High-Availability and Link Aggregation for more environments.

The mlx4 driver reacts on netdev events generated by bonding when
slave state changes happen by programming a HW V2P (Virt-to-Phys)
port table. Bonding was extended to expose these state changes
through netdev events.

When an mlx4 interface such as the mlx4 IB/RoCE driver is subject to
this policy, QPs are created over virtual ports which are mapped
to one of the two physical ports. When a failure happens, the
re-programming of the V2P table allows traffic to keep flowing.

The mlx4 Ethernet driver interfaces are not subject to this
policy and act as usual.

A 2nd use-case for this model would be to add HA and Link Aggregation
support to single ported mlx4 Ethernet VFs. In this case, the PF Ethernet
intrfaces are bonded, all the VFs see single port devices (which is
supported already today), and VF QPs are subject to V2P.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

When the mlx4 IB (RoCE) device works in link aggregation mode, it
exposes a single port to upper layers. Therefore, applications always
set '1' in port_num attribute when modifying a QP or creating an address handle.

To make sure that a node uses all available ports the mlx4 driver will
override the port_num attribute with a round robin policy.
Signed-off-by: Moni Shoua <monis@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

In port aggregation mode flows for port #1 (the only port) should be mirrored
on port #2. This is because packets can arrive from either physical ports.
Signed-off-by: Moni Shoua <monis@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Register the interface with the mlx4 core driver with port aggregation support
and check for port aggregation mode when the 'add' function is called.

In this mode, only one physical port is reported to the upper layer
(RoCE/IB core stack and ULPs).
Signed-off-by: Moni Shoua <monis@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This function is implemented twice... get rid of one copy.
Signed-off-by: Moni Shoua <monis@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Capture NETDEV events generated by the bonding driver and based on that
make decisions of how to configure port aggregation in the mlx4 core driver.

This includes setting the V2P port table and re-creating the interested
interfaces in bonded/non-bonded mode.
Signed-off-by: Moni Shoua <monis@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Supply interface functions to bond and unbond ports of a mlx4 internal
interfaces. Example for such an interface is the one registered by the
mlx4 IB driver under RoCE.

There are

1. Functions to go in/out to/from bonded mode
2. Function to remap virtual ports to physical ports

The bond_mutex prevents simultaneous access to data that keep status of
the device in bonded mode.

The upper mlx4 interface marks to the mlx4 core module that they
want to be subject for such bonding by setting the MLX4_INTFF_BONDING
flag. Interface which goes to/from bonded mode is re-created.

The mlx4 Ethernet driver does not set this flag when registering the
interface, the IB driver does.
Signed-off-by: Moni Shoua <monis@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Implement the hardware interface required for port aggregation.

1. Disable RX port check on receive - don't perform a validity check
that matches to QP's port and the port where the packet is received.

2. Virtual to physical port remap - configure virtual to physical port
mapping. Port remap capability for virtual functions.
Signed-off-by: Moni Shoua <monis@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Use notifier chain to dispatch an event upon a change in slave state.
Event is dispatched with slave specific info.
Signed-off-by: Moni Shoua <monis@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Move slave state changes to a helper function, this is a pre-step for adding
functionality of dispatching an event when this helper is called.

This commit doesn't add new functionality.
Signed-off-by: Moni Shoua <monis@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Add event which provides an indication on a change in the state
of a bonding slave. The event handler should cast the pointer to the
appropriate type (struct netdev_bonding_info) in order to get the
full info about the slave.
Signed-off-by: Moni Shoua <monis@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Jon Maloy says:

====================
tipc: some small fixes

During extensive testing and analysis of running dual links between
nodes, we have encountered some issues that potentially may cause
problems. We choose to fix those proactively in this series.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

When a new link instance is created, it is trigged to start by
sending it a TIPC_STARTING_EVT, whereafter a regular link
reset is applied to it.

The starting event is codewise treated as a timeout event, and prompts
a link RESET message to be sent to the peer node, carrying a link
session identifier. The later link_reset() call nudges this session
identifier, whereafter all subsequent RESET messages will be sent out
with the new identifier. The latter session number overrides the former,
causing the peer to unconditionally accept it irrespective of its
current working state.

We don't think that this causes any problem, but it is not in accordance
with the protocol spec, and may cause confusion when debugging TIPC
sessions.

To avoid this, we make the starting event distinct from the
subsequent timeout events, by not allowing the former to send
out any RESET message. This eliminates the described problem.
Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Reviewed-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>

Instances of struct node are created in the function tipc_disc_rcv()
under the assumption that there is no race between received discovery
messages arriving from the same node. This assumption is wrong.
When we use more than one bearer, it is possible that discovery
messages from the same node arrive at the same moment, resulting in
creation of two instances of struct tipc_node. This may later cause
confusion during link establishment, and may result in one of the links
never becoming activated.

We fix this by making lookup and potential creation of nodes atomic.
Instead of first looking up the node, and in case of failure, create it,
we now start with looking up the node inside node_link_create(), and
return a reference to that one if found. Otherwise, we go ahead and
create the node as we did before.
Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Reviewed-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>

During link failover it may happen that the remaining link goes
down while it is still in the process of taking over traffic
from a previously failed link. When this happens, we currently
abort the failover procedure and reset the first failed link to
non-failover mode, so that it will be ready to re-establish
contact with its peer when it comes available.

However, if the first link goes down because its bearer was manually
disabled, it is not enough to reset it; it must also be deleted;
which is supposed to happen when the failover procedure is finished.
Otherwise it will remain a zombie link: attached to the owner node
structure, in mode LINK_STOPPED, and permanently blocking any re-
establishing of the link to the peer via the interface in question.

We fix this by amending the failover abort procedure. Apart from
resetting the link to non-failover state, we test if the link is
also in LINK_STOPPED mode. If so, we delete it, using the conditional
tipc_link_delete() function introduced in the previous commit.
Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Reviewed-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>

When a bearer is disabled, all pertaining links will be reset and
deleted. However, if there is a second active link towards a killed
link's destination, the delete has to be postponed until the failover
is finished. During this interval, we currently put the link in zombie
mode, i.e., we take it out of traffic, delete its timer, but leave it
attached to the owner node structure until all missing packets have
been received.  When this is done, we detach the link from its node
and delete it, assuming that the synchronous timer deletion that was
initiated earlier in a different thread has finished.

This is unsafe, as the failover may finish before del_timer_sync()
has returned in the other thread.

We fix this by adding an atomic reference counter of type kref in
struct tipc_link. The counter keeps track of the references kept
to the link by the owner node and the timer. We then do a conditional
delete, based on the reference counter, both after the failover has
been finished and when the timer expires, if applicable. Whoever
comes last, will actually delete the link. This approach also implies
that we can make the deletion of the timer asynchronous.
Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Reviewed-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>

Merge tag 'mac80211-next-for-davem-2015-02-03' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next

Last round of updates for net-next:
 * revert a patch that caused a regression with mesh userspace (Bob)
 * fix a number of suspend/resume related races
   (from Emmanuel, Luca and myself - we'll look at backporting later)
 * add software implementations for new ciphers (Jouni)
 * add a new ACPI ID for Broadcom's rfkill (Mika)
 * allow using netns FD for wireless (Vadim)
 * some other cleanups (various)
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch is to use firmware version macros from t4fw_version.h
and also enables 40g T5 adapter.
Signed-off-by: Praveen Madhavan <praveenm@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This is only an API consolidation and should make things more readable
it replaces var * HZ / 1000 by msecs_to_jiffies(var).

As there is a discrepancy between the code and the comments this is in
a separate patch.
Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

This is only an API consolidation and should make things more readable
it replaces var * HZ / 1000 by msecs_to_jiffies(var).
Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Merge branch 'for-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth-next

Johan Hedberg says:

====================
pull request: bluetooth-next 2015-02-03

Here's what's likely the last bluetooth-next pull request for 3.20.
Notable changes include:

 - xHCI workaround + a new id for the ath3k driver
 - Several new ids for the btusb driver
 - Support for new Intel Bluetooth controllers
 - Minor cleanups to ieee802154 code
 - Nested sleep warning fix in socket accept() code path
 - Fixes for Out of Band pairing handling
 - Support for LE scan restarting for HCI_QUIRK_STRICT_DUPLICATE_FILTER
 - Improvements to data we expose through debugfs
 - Proper handling of Hardware Error HCI events

Please let me know if there are any issues pulling. Thanks.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch adds skb_remcsum_process and skb_gro_remcsum_process to
perform the appropriate adjustments to the skb when receiving
remote checksum offload.

Updated vxlan and gue to use these functions.

Tested: Ran TCP_RR and TCP_STREAM netperf for VXLAN and GUE, did
not see any change in performance.
Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

bridge: Let bridge not age 'externally' learnt FDB entries, they are removed when 'external' entity notifies the aging

When 'learned_sync' flag is turned on, the offloaded switch
 port syncs learned MAC addresses to bridge's FDB via switchdev notifier
 (NETDEV_SWITCH_FDB_ADD). Currently, FDB entries learnt via this mechanism are
 wrongly being deleted by bridge aging logic. This patch ensures that FDB
 entries synced from offloaded switch ports are not deleted by bridging logic.
 Such entries can only be deleted via switchdev notifier
 (NETDEV_SWITCH_FDB_DEL).
Signed-off-by: Siva Mannem <siva.mannem.lnx@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Freescale ethernet controllers have the capability to re-assemble fragmented
data into a single ethernet frame. This patch uses this capability and
implements NETIP_F_SG feature into the fs_enet ethernet driver.

On a MPC885, I get 53% performance improvement on a ftp transfer of a 15Mb file:
  * Without the patch : 2,8 Mbps
  * With the patch : 4,3 Mbps
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>