Sameeh Jubran says:
====================
Introduce XDP to ena
This patchset includes 3 patches:
* XDP_DROP implementation
* XDP_TX implementation
* A fix for an issue which might occur due to the XDP_TX patch. I see fit
to place it as a standalone patch for clarity.
Difference from v2:
* Fixed the usage of rx headroom (XDP_PACKET_HEADROOM)
* Aligned the page_offset of the packet when passing it to the stack
* Switched to using xdp_frame in xdp xmit queue
* Dropped the print for unsupported commands
* Cosmetic changes
Difference from RFC v1 (XDP_DROP patch):
* Initialized xdp.rxq pointer
* Updated max_mtu on attachment of xdp and removed the check from
ena_change_mtu()
* Moved the xdp execution from ena_rx_skb() to ena_clean_rx_irq()
* Moved xdp buff (struct xdp_buff) from rx_ring to the local stack
* Started using netlink's extack mechanism to deliver error messages to
the user
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
The first_interrupt field is accessed in ena_intr_msix_io() upon
receiving an interrupt.The rx_ring and tx_ring fields of napi can
be NULL when receiving interrupt for xdp queues. This patch fixes
the issue by moving the field to the ena_napi struct.
Signed-off-by: Sameeh Jubran <sameehj@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit implements the XDP_TX action in the ena driver. We allocate
separate tx queues for the XDP_TX. We currently allow xdp only when
there is enough queues to allocate for xdp.
Signed-off-by: Sameeh Jubran <sameehj@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit implements the basic functionality of drop/pass logic in the
ena driver.
Signed-off-by: Sameeh Jubran <sameehj@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Michal Kubecek says:
====================
ethtool netlink interface, preliminary part
As Jakub Kicinski suggested in ethtool netlink v7 discussion, this
submission consists only of preliminary patches which raised no objections;
first four patches already have Acked-by or Reviewed-by.
- patch 1 exposes permanent hardware address (as shown by "ethtool -P")
via rtnetlink
- patch 2 is renames existing netlink helper to a better name
- patch 3 and 4 reorganize existing ethtool code (no functional change)
- patch 5 makes the table of link mode names available as an ethtool string
set (will be needed for the netlink interface)
Once we get these out of the way, v8 of the first part of the ethtool
netlink interface will follow.
Changes from v2 to v3: fix SPDX licence identifiers (patch 3 and 5).
Changes from v1 to v2: restore build time check that all link modes have
assigned a name (patch 5).
====================
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Unlike e.g. netdev features, the ethtool ioctl interface requires link mode
table to be in sync between kernel and userspace for userspace to be able
to display and set all link modes supported by kernel. The way arbitrary
length bitsets are implemented in netlink interface, this will be no longer
needed.
To allow userspace to access all link modes running kernel supports, add
table of ethernet link mode names and make it available as a string set to
userspace GET_STRSET requests. Add build time check to make sure names
are defined for all modes declared in enum ethtool_link_mode_bit_indices.
Once the string set is available, make it also accessible via ioctl.
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Introduce file net/ethtool/common.c for code shared by ioctl and netlink
ethtool interface. Move name tables of features, RSS hash functions,
tunables and PHY tunables into this file.
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The ethtool netlink interface is going to be split into multiple files so
that it will be more convenient to put all of them in a separate directory
net/ethtool. Start by moving current ethtool.c with ioctl interface into
this directory and renaming it to ioctl.c.
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Function nl80211_validate_nested() is not specific to nl80211, it's
a counterpart to nla_validate_nested_deprecated() with strict validation.
For consistency with other validation and parse functions, rename it to
nla_validate_nested().
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Permanent hardware address of a network device was traditionally provided
via ethtool ioctl interface but as Jiri Pirko pointed out in a review of
ethtool netlink interface, rtnetlink is much more suitable for it so let's
add it to the RTM_NEWLINK message.
Add IFLA_PERM_ADDRESS attribute to RTM_NEWLINK messages unless the
permanent address is all zeros (i.e. device driver did not fill it). As
permanent address is not modifiable, reject userspace requests containing
IFLA_PERM_ADDRESS attribute.
Note: we already provide permanent hardware address for bond slaves;
unfortunately we cannot drop that attribute for backward compatibility
reasons.
v5 -> v6: only add the attribute if permanent address is not zero
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Kirill Tkhai says:
====================
unix: Show number of scm files in fdinfo
v2: Pass correct argument to locked in patch [2/2].
Unix sockets like a block box. You never know what is pending there:
there may be a file descriptor holding a mount or a block device,
or there may be whole universes with namespaces, sockets with receive
queues full of sockets etc.
The patchset makes number of pending scm files be visible in fdinfo.
This may be useful to determine, that socket should be investigated
or which task should be killed to put a reference counter on a resourse.
$cat /proc/[pid]/fdinfo/[unix_sk_fd] | grep scm_fds
scm_fds: 1
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Unix sockets like a block box. You never know what is stored there:
there may be a file descriptor holding a mount or a block device,
or there may be whole universes with namespaces, sockets with receive
queues full of sockets etc.
The patch adds a little debug and accounts number of files (not recursive),
which is in receive queue of a unix socket. Sometimes this is useful
to determine, that socket should be investigated or which task should
be killed to put reference counter on a resourse.
v2: Pass correct argument to lockdep
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This adds .show_fdinfo to socket_file_ops, so protocols will be able
to print their specific data in fdinfo.
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Stefano Garzarella says:
====================
vsock: add local transport support
v2:
- style fixes [Dave]
- removed RCU sync and changed 'the_vsock_loopback' in a global
static variable [Stefan]
- use G2H transport when local transport is not loaded and remote cid
is VMADDR_CID_LOCAL [Stefan]
- rebased on net-next
v1: https://patchwork.kernel.org/cover/11251735/
This series introduces a new transport (vsock_loopback) to handle
local communication.
This could be useful to test vsock core itself and to allow developers
to test their applications without launching a VM.
Before this series, vmci and virtio transports allowed this behavior,
but only in the guest.
We are moving the loopback handling in a new transport, because it
might be useful to provide this feature also in the host or when
no H2G/G2H transports (hyperv, virtio, vmci) are loaded.
The user can use the loopback with the new VMADDR_CID_LOCAL (that
replaces VMADDR_CID_RESERVED) in any condition.
Otherwise, if the G2H transport is loaded, it can also use the guest
local CID as previously supported by vmci and virtio transports.
If G2H transport is not loaded, the user can also use VMADDR_CID_HOST
for local communication.
Patch 1 is a cleanup to build virtio_transport_common without virtio
Patch 2 adds the new VMADDR_CID_LOCAL, replacing VMADDR_CID_RESERVED
Patch 3 adds a new feature flag to register a loopback transport
Patch 4 adds the new vsock_loopback transport based on the loopback
implementation of virtio_transport
Patch 5 implements the logic to use the local transport for loopback
communication
Patch 6 removes the loopback from virtio_transport
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
We can remove the loopback handling from virtio_transport,
because now the vsock core is able to handle local communication
using the new vsock_loopback device.
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now that we have a transport that can handle the local communication,
we can use it when it is loaded.
A socket will use the local transport (loopback) when the remote
CID is:
- equal to VMADDR_CID_LOCAL
- or equal to transport_g2h->get_local_cid(), if transport_g2h
is loaded (this allows us to keep the same behavior implemented
by virtio and vmci transports)
- or equal to VMADDR_CID_HOST, if transport_g2h is not loaded
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds a new vsock_loopback transport to handle local
communication.
This transport is based on the loopback implementation of
virtio_transport, so it uses the virtio_transport_common APIs
to interface with the vsock core.
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch allows to register a transport able to handle
local communication (loopback).
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The VMADDR_CID_RESERVED (1) was used by VMCI, but now it is not
used anymore, so we can reuse it for local communication
(loopback) adding the new well-know CID: VMADDR_CID_LOCAL.
Cc: Jorgen Hansen <jhansen@vmware.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Jorgen Hansen <jhansen@vmware.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We can remove virtio header includes, because virtio_transport_common
doesn't use virtio API, but provides common functions to interface
virtio/vhost transports with the af_vsock core, and to handle
the protocol.
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Russell King says:
====================
Add support for slow-to-probe-PHY copper SFP modules
This series, following on from the previous adding SFP+ copper support,
adds support for a range of Copper SFP modules, made by a variety of
companies, all of which have a Marvell 88E1111 PHY on them, but take
far longer than the Marvell spec'd 15ms to start communicating on the
I2C bus.
Researching the Champion One 1000SFPT module reveals that TX_DISABLE is
routed through a MAX1971 switching regulator and reset IC which adds a
175ms delay to releasing the 88E1111 reset.
It is not known whether other modules use a similar setup, but there
are a range of modules that are slow for the Marvell PHY to appear.
This patch series adds support for these modules by repeatedly trying
to probe the PHY for up to 600ms.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Some 1000BASE-T PHY modules take a while for the PHY to wake up.
Retry the probe a number of times before deciding that the module has
no PHY.
Tested with:
Sourcephotonics SPGBTXCNFC - PHY takes less than 50ms to respond.
Champion One 1000SFPT - PHY takes about 200ms to respond.
Mikrotik S-RJ01 - no PHY
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Rename sm_retries as sm_fault_retries, as this is what this member is
tracking.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Russell King says:
====================
Add support for SFP+ copper modules
This series adds support for Copper SFP+ modules with Clause 45 PHYs.
Specifically the patches:
1. drop support for the probably never tested 100BASE-*X modules.
2. drop EEPROM ID from sfp_select_interface()
3. add more compliance code definitions from SFF-8024, renaming the
existing definitions.
4. add module start/stop methods so phylink knows when a module is
about to become active. The module start method is called after
we have probed for a PHY on the module.
5. move start/stop of module PHY down into phylink using the new
module start/stop methods.
6. add support for Clause 45 I2C accesses, tested with Methode DM7052.
Other modules appear to use the same protocol, but slight
differences, but I do not have those modules to test with.
(if someone does, please holler!)
7. rearrange how we attach to PHYs so that we can support Clause 45
PHYs with indeterminant interface modes. (Clause 45 PHYs appear
to like to change their PHY interface mode depending on the
negotiated speed.)
8. add support for phylink to connect to a clause 45 PHY on a SFP
module.
9. split the link_an_mode between the configured value and the
currently selected mode value; some clause 45 PHYs have no
capability to provide in-band negotiation.
10. split the link configuration on SFP module insertion in phylink
so we can use it in other code paths.
11. delay MAC configuration for copper modules without a PHY to the
module start method - after any module PHY has been probed. If
the module has a PHY, then we setup the MAC when the PHY is
detected.
12. the Broadcom 84881 PHY does not support in-band negotiation even
though it uses SGMII and 2500BASE-X. Having the MAC operating
with in-band negotiation enabled, even with AN bypass enabled,
results in no link - Broadcom say that the host MAC must always
be forced.
13. add support for the Broadcom 84881 PHY found on the Methode
DM7052 module.
14. add support to SFP to probe for a Clause 45 PHY on copper SFP+
modules.
v3: now bisectable!
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Some SFP+ modules have a Clause 45 PHY onboard, which is accessible via
the normal I2C address. Detect 10G BASE-T PHYs which may have an
accessible PHY and probe for it.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a rudimentary Clause 45 driver for the BCM84881 PHY, found on
Methode DM7052 SFPs.
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
The Broadcom BCM84881 does not appear to send the SGMII control word
when operating in SGMII mode, which causes network adapters to fail
to link with the PHY, or decide to operate at fixed 1G speed, even if
the PHY negotiated 100M.
Work around this by detecting the Broadcom BCM84881 and switch to phy
mode rather than inband mode.
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Knowing whether we need to delay the MAC configuration because a module
may have a PHY is useful to phylink to allow NBASE-T modules to work on
systems supporting no more than 2.5G speeds.
This commit allows us to delay such configuration until after the PHY
has been probed by recording the parsed capabilities, and if the module
may have a PHY, doing no more until the module_start() notification is
called. At that point, we either have a PHY, or we don't.
We move the PHY-based setup a little later, and use the PHYs support
capabilities rather than the EEPROM parsed capabilities to determine
whether we can support the PHY.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Split out the configuration step from phylink_sfp_module_insert() so
we can re-use this later.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Split link_an_mode between the configured setting and the current
operating setting. This is an important distinction to make when we
need to configure PHY mode for a plugged SFP+ module that does not
use in-band signalling.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some SFP+ modules have Clause 45 PHYs embedded on them, which need a
little more handling in order to ensure that they are correctly setup,
as they switch the PHY link mode according to the negotiated speed.
With Clause 22 PHYs, we assumed that they would operate in SGMII mode,
but this assumption is now false. Adapt phylink to support Clause 45
PHYs on SFP+ modules.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
In order to support Clause 45 PHYs on SFP+ modules, which have an
indeterminant phy interface mode, we need to be able to call
phylink_bringup_phy() with a different interface mode to that used when
binding the PHY. Reduce __phylink_connect_phy() to an attach operation,
and move the call to phylink_bringup_phy() to its call sites.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some SFP+ modules have PHYs on them just like SFP modules do, except
they are Clause 45 PHYs. The I2C protocol used to access them is
modified slightly in order to send the device address and 16-bit
register index.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move phy_start() and phy_stop() into the module_start and module_stop
notifications in phylink, rather than having them in the SFP code.
This gives phylink responsibility for controlling the PHY, rather
than having SFP start and stop the PHY state machine.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
When dealing with some copper modules, we can't positively know the
module capabilities are until we have probed the PHY. Without the full
capabilities, we may end up failing a module that we could otherwise
drive with a restricted set of capabilities.
An example of this would be a module with a NBASE-T PHY plugged into
a host that supports phy interface modes 2500BASE-X and SGMII. The
PHY supports 10GBASE-R, 5000BASE-X, 2500BASE-X, SGMII interface modes,
which means a subset of the capabilities are compatible with the host.
However, reading the module EEPROM leads us to believe that the module
only supports ethtool link mode 10GBASE-T, which is incompatible with
the host - and thus results in the module being rejected.
This patch adds an extra notification which are triggered after the
SFP module's PHY probe, and a corresponding notification just before
the PHY is removed.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
SFF-8024 is used to define various constants re-used in several SFF
SFP-related specifications. Split these constants from the enum, and
rename them to indicate that they're defined by SFF-8024.
Add and use updated SFF-8024 extended compliance code definitions for
10GBASE-T, 5GBASE-T and 2.5GBASE-T modules.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
We don't need the EEPROM ID to derive the phy interface mode as we can
derive it merely from the ethtool link modes. Remove the EEPROM ID
argument to sfp_select_interface().
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
The 100BASE-FX and 100BASE-LX support assumes a PHY is present; this
is probably an incorrect assumption. In any case, sfp_parse_support()
will fail such a module. Let's stop pretending we support these
modules.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
T6 has a separate region known as high priority filter region
that allows classifying packets going through ULD path. So,
query firmware for HPFILTER resources and enable the high
priority offload filter support when it is available.
Signed-off-by: Shahjada Abul Husain <shahjada@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fixes gcc '-Wunused-but-set-variable' warning:
drivers/net/ethernet/freescale/enetc/enetc_qos.c: In function enetc_setup_tc_cbs:
drivers/net/ethernet/freescale/enetc/enetc_qos.c:195:6: warning: variable tc_max_sized_frame set but not used [-Wunused-but-set-variable]
Fixes: c431047c4e ("enetc: add support Credit Based Shaper(CBS) for hardware offload")
Signed-off-by: Chen Wandun <chenwandun@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Device stats are currently hard coded in the PCI BAR0 layout.
Add a ability to read them from the TLV area instead.
Names for the stats are maintained by the driver, and their
meaning documented. This allows us to more easily add and
remove device stats.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When a TCP socket is created, sk->sk_state is initialized twice as
TCP_CLOSE in sock_init_data() and tcp_init_sock(). The tcp_init_sock() is
always called after the sock_init_data(), so it is not necessary to update
sk->sk_state in the tcp_init_sock().
Before v2.1.8, the code of the two functions was in the inet_create(). In
the patch of v2.1.8, the tcp_v4/v6_init_sock() were added and the code of
initialization of sk->state was duplicated.
Signed-off-by: Kuniyuki Iwashima <kuni1840@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Provide a software TX timestamp and add it to the ethtool query
interface.
skb_tx_timestamp() is also needed if one would like to use PHY
timestamping.
Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: David S. Miller <davem@davemloft.net>
Jon Maloy says:
====================
tipc: introduce variable window congestion control
We improve thoughput greatly by introducing a variety of the Reno
congestion control algorithm at the link level.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
We introduce a simple variable window congestion control for links.
The algorithm is inspired by the Reno algorithm, covering both 'slow
start', 'congestion avoidance', and 'fast recovery' modes.
- We introduce hard lower and upper window limits per link, still
different and configurable per bearer type.
- We introduce a 'slow start theshold' variable, initially set to
the maximum window size.
- We let a link start at the minimum congestion window, i.e. in slow
start mode, and then let is grow rapidly (+1 per rceived ACK) until
it reaches the slow start threshold and enters congestion avoidance
mode.
- In congestion avoidance mode we increment the congestion window for
each window-size number of acked packets, up to a possible maximum
equal to the configured maximum window.
- For each non-duplicate NACK received, we drop back to fast recovery
mode, by setting the both the slow start threshold to and the
congestion window to (current_congestion_window / 2).
- If the timeout handler finds that the transmit queue has not moved
since the previous timeout, it drops the link back to slow start
and forces a probe containing the last sent sequence number to the
sent to the peer, so that this can discover the stale situation.
This change does in reality have effect only on unicast ethernet
transport, as we have seen that there is no room whatsoever for
increasing the window max size for the UDP bearer.
For now, we also choose to keep the limits for the broadcast link
unchanged and equal.
This algorithm seems to give a 50-100% throughput improvement for
messages larger than MTU.
Suggested-by: Xin Long <lucien.xin@gmail.com>
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>
When we increase the link tranmsit window we often observe the following
scenario:
1) A STATE message bypasses a sequence of traffic packets and arrives
far ahead of those to the receiver. STATE messages contain a
'peers_nxt_snt' field to indicate which was the last packet sent
from the peer. This mechanism is intended as a last resort for the
receiver to detect missing packets, e.g., during very low traffic
when there is no packet flow to help early loss detection.
3) The receiving link compares the 'peer_nxt_snt' field to its own
'rcv_nxt', finds that there is a gap, and immediately sends a
NACK message back to the peer.
4) When this NACKs arrives at the sender, all the requested
retransmissions are performed, since it is a first-time request.
Just like in the scenario described in the previous commit this leads
to many redundant retransmissions, with decreased throughput as a
consequence.
We fix this by adding two more conditions before we send a NACK in
this sitution. First, the deferred queue must be empty, so we cannot
assume that the potential packet loss has already been detected by
other means. Second, we check the 'peers_snd_nxt' field only in probe/
probe_reply messages, thus turning this into a true mechanism of last
resort as it was really meant to be.
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>
When we increase the link send window we sometimes observe the
following scenario:
1) A packet #N arrives out of order far ahead of a sequence of older
packets which are still under way. The packet is added to the
deferred queue.
2) The missing packets arrive in sequence, and for each 16th of them
an ACK is sent back to the receiver, as it should be.
3) When building those ACK messages, it is checked if there is a gap
between the link's 'rcv_nxt' and the first packet in the deferred
queue. This is always the case until packet number #N-1 arrives, and
a 'gap' indicator is added, effectively turning them into NACK
messages.
4) When those NACKs arrive at the sender, all the requested
retransmissions are done, since it is a first-time request.
This sometimes leads to a huge amount of redundant retransmissions,
causing a drop in max throughput. This problem gets worse when we
in a later commit introduce variable window congestion control,
since it drops the link back to 'fast recovery' much more often
than necessary.
We now fix this by not sending any 'gap' indicator in regular ACK
messages. We already have a mechanism for sending explicit NACKs
in place, and this is sufficient to keep up the packet flow.
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>
Clang warns:
../drivers/net/ppp/ppp_async.c:877:6: warning: misleading indentation;
statement is not part of the previous 'if' [-Wmisleading-indentation]
ap->rpkt = skb;
^
../drivers/net/ppp/ppp_async.c:875:5: note: previous statement is here
if (!skb)
^
1 warning generated.
This warning occurs because there is a space before the tab on this
line. Clean up this entire block's indentation so that it is consistent
with the Linux kernel coding style and clang no longer warns.
Fixes: 6722e78c90 ("[PPP]: handle misaligned accesses")
Link: https://github.com/ClangBuiltLinux/linux/issues/800
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller