kernel/net/core/net-sysfs.c, branch linux-4.1.y

dev: introduce dev_get_iflink()

2015-04-02T18:04:59Z

The goal of this patch is to prepare the removal of the iflink field. It introduces a new ndo function, which will be implemented by virtual interfaces. There is no functional change into this patch. All readers of iflink field now call dev_get_iflink(). Signed-off-by: Nicolas Dichtel Signed-off-by: David S. Miller

net: add support for phys_port_name

2015-03-19T02:30:35Z

Similar to port id allow netdevices to specify port names and export the name via sysfs. Drivers can implement the netdevice operation to assist udev in having sane default names for the devices using the rule: $ cat /etc/udev/rules.d/80-net-setup-link.rules SUBSYSTEM=="net", ACTION=="add", ATTR{phys_port_name}!="", NAME="$attr{phys_port_name}" Use of phys_name versus phys_id was suggested-by Jiri Pirko. Signed-off-by: David Ahern Acked-by: Jiri Pirko Acked-by: Scott Feldman Signed-off-by: David S. Miller

net: Add max rate tx queue attribute

2015-03-18T18:55:18Z

This adds a tx_maxrate attribute to the tx queue sysfs entry allowing for max-rate limiting. Along with DCB-ETS and BQL this provides another knob to tune queue performance. The limit units are Mbps. By default it is disabled. To disable the rate limitation after it has been set for a queue, it should be set to zero. Signed-off-by: John Fastabend Signed-off-by: Or Gerlitz Signed-off-by: David S. Miller

net: core: add of_find_net_device_by_node()

2015-03-10T03:50:20Z

Add a helper function which allows getting the struct net_device pointer associated with a given struct device_node pointer. This is useful for instance for DSA Ethernet devices not backed by a platform_device, but a PCI device. Since we need to access net_class which is not accessible outside of net/core/net-sysfs.c, this helper function is also added here and gated with CONFIG_OF_NET. Network devices initialized with SET_NETDEV_DEV() are also taken into account by checking for dev->parent first and then falling back to checking the device pointer within struct net_device. Signed-off-by: Florian Fainelli Signed-off-by: David S. Miller

net: use %*pb[l] to print bitmaps including cpumasks and nodemasks

2015-02-14T05:21:38Z

printk and friends can now format bitmaps using '%*pb[l]'. cpumask and nodemask also provide cpumask_pr_args() and nodemask_pr_args() respectively which can be used to generate the two printf arguments necessary to format the specified cpu/nodemask. Signed-off-by: Tejun Heo Acked-by: David S. Miller Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

net-sysfs: expose physical switch id for particular device

2014-12-03T04:01:22Z

Signed-off-by: Jiri Pirko Reviewed-by: Thomas Graf Acked-by: John Fastabend Acked-by: Andy Gospodarek Acked-by: Florian Fainelli Signed-off-by: David S. Miller

net: rename netdev_phys_port_id to more generic name

2014-12-03T04:01:19Z

So this can be reused for identification of other "items" as well. Signed-off-by: Jiri Pirko Reviewed-by: Thomas Graf Acked-by: John Fastabend Acked-by: Andy Gospodarek Acked-by: Jamal Hadi Salim Signed-off-by: David S. Miller

net: gro: add a per device gro flush timer

2014-11-10T17:05:59Z

Tuning coalescing parameters on NIC can be really hard. Servers can handle both bulk and RPC like traffic, with conflicting goals : bulk flows want as big GRO packets as possible, RPC want minimal latencies. To reach big GRO packets on 10Gbe NIC, one can use : ethtool -C eth0 rx-usecs 4 rx-frames 44 But this penalizes rpc sessions, with an increase of latencies, up to 50% in some cases, as NICs generally do not force an interrupt when a packet with TCP Push flag is received. Some NICs do not have an absolute timer, only a timer rearmed for every incoming packet. This patch uses a different strategy : Let GRO stack decides what do do, based on traffic pattern. Packets with Push flag wont be delayed. Packets without Push flag might be held in GRO engine, if we keep receiving data. This new mechanism is off by default, and shall be enabled by setting /sys/class/net/ethX/gro_flush_timeout to a value in nanosecond. To fully enable this mechanism, drivers should use napi_complete_done() instead of napi_complete(). Tested: Ran 200 netperf TCP_STREAM from A to B (10Gbe mlx4 link, 8 RX queues) Without this feature, we send back about 305,000 ACK per second. GRO aggregation ratio is low (811/305 = 2.65 segments per GRO packet) Setting a timer of 2000 nsec is enough to increase GRO packet sizes and reduce number of ACK packets. (811/19.2 = 42) Receiver performs less calls to upper stacks, less wakes up. This also reduces cpu usage on the sender, as it receives less ACK packets. Note that reducing number of wakes up increases cpu efficiency, but can decrease QPS, as applications wont have the chance to warmup cpu caches doing a partial read of RPC requests/answers if they fit in one skb. B:~# sar -n DEV 1 10 | grep eth0 | tail -1 Average: eth0 811269.80 305732.30 1199462.57 19705.72 0.00 0.00 0.50 B:~# echo 2000 >/sys/class/net/eth0/gro_flush_timeout B:~# sar -n DEV 1 10 | grep eth0 | tail -1 Average: eth0 811577.30 19230.80 1199916.51 1239.80 0.00 0.00 0.50 Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller

net: do not name the pointer to struct net_device net

2014-07-25T06:33:55Z

"net" is normally for struct net*, pointer to struct net_device should be named to either "dev" or "ndev" etc. Cc: "David S. Miller" Signed-off-by: Cong Wang Signed-off-by: David S. Miller

net: add name_assign_type netdev attribute

2014-07-15T23:12:01Z

Based on a patch by David Herrmann. The name_assign_type attribute gives hints where the interface name of a given net-device comes from. These values are currently defined: NET_NAME_ENUM: The ifname is provided by the kernel with an enumerated suffix, typically based on order of discovery. Names may be reused and unpredictable. NET_NAME_PREDICTABLE: The ifname has been assigned by the kernel in a predictable way that is guaranteed to avoid reuse and always be the same for a given device. Examples include statically created devices like the loopback device and names deduced from hardware properties (including being given explicitly by the firmware). Names depending on the order of discovery, or in any other way on the existence of other devices, must not be marked as PREDICTABLE. NET_NAME_USER: The ifname was provided by user-space during net-device setup. NET_NAME_RENAMED: The net-device has been renamed from userspace. Once this type is set, it cannot change again. NET_NAME_UNKNOWN: This is an internal placeholder to indicate that we yet haven't yet categorized the name. It will not be exposed to userspace, rather -EINVAL is returned. The aim of these patches is to improve user-space renaming of interfaces. As a general rule, userspace must rename interfaces to guarantee that names stay the same every time a given piece of hardware appears (at boot, or when attaching it). However, there are several situations where userspace should not perform the renaming, and that depends on both the policy of the local admin, but crucially also on the nature of the current interface name. If an interface was created in repsonse to a userspace request, and userspace already provided a name, we most probably want to leave that name alone. The main instance of this is wifi-P2P devices created over nl80211, which currently have a long-standing bug where they are getting renamed by udev. We label such names NET_NAME_USER. If an interface, unbeknown to us, has already been renamed from userspace, we most probably want to leave also that alone. This will typically happen when third-party plugins (for instance to udev, but the interface is generic so could be from anywhere) renames the interface without informing udev about it. A typical situation is when you switch root from an installer or an initrd to the real system and the new instance of udev does not know what happened before the switch. These types of problems have caused repeated issues in the past. To solve this, once an interface has been renamed, its name is labelled NET_NAME_RENAMED. In many cases, the kernel is actually able to name interfaces in such a way that there is no need for userspace to rename them. This is the case when the enumeration order of devices, or in fact any other (non-parent) device on the system, can not influence the name of the interface. Examples include statically created devices, or any naming schemes based on hardware properties of the interface. In this case the admin may prefer to use the kernel-provided names, and to make that possible we label such names NET_NAME_PREDICTABLE. We want the kernel to have tho possibilty of performing predictable interface naming itself (and exposing to userspace that it has), as the information necessary for a proper naming scheme for a certain class of devices may not be exposed to userspace. The case where renaming is almost certainly desired, is when the kernel has given the interface a name using global device enumeration based on order of discovery (ethX, wlanY, etc). These naming schemes are labelled NET_NAME_ENUM. Lastly, a fallback is left as NET_NAME_UNKNOWN, to indicate that a driver has not yet been ported. This is mostly useful as a transitionary measure, allowing us to label the various naming schemes bit by bit. v8: minor documentation fixes v9: move comment to the right commit Signed-off-by: Tom Gundersen Reviewed-by: David Herrmann Reviewed-by: Kay Sievers Signed-off-by: David S. Miller