- 03 Mar, 2022 40 commits
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Martin KaFai Lau authored
A latter patch will postpone the delivery_time clearing until the stack knows the skb is being delivered locally. That will allow other kernel forwarding path (e.g. ip[6]_forward) to keep the delivery_time also. An earlier attempt was to do skb_clear_delivery_time() in ip_local_deliver() and ip6_input(). The discussion [0] requested to move it one step later into ip_local_deliver_finish() and ip6_input_finish() so that the delivery_time can be kept for the ip_vs forwarding path also. To do that, this patch also needs to take care of the (rcv) timestamp usecase in ip_is_fragment(). It needs to expect delivery_time in the skb->tstamp, so it needs to save the mono_delivery_time bit in inet_frag_queue such that the delivery_time (if any) can be restored in the final defragmented skb. [Note that it will only happen when the locally generated skb is looping from egress to ingress over a virtual interface (e.g. veth, loopback...), skb->tstamp may have the delivery time before it is known that it will be delivered locally and received by another sk.] [0]: https://lore.kernel.org/netdev/ca728d81-80e8-3767-d5e-d44f6ad96e43@ssi.bg/Signed-off-by:
Martin KaFai Lau <kafai@fb.com> Signed-off-by:
David S. Miller <davem@davemloft.net>
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Martin KaFai Lau authored
The previous patches handled the delivery_time before sch_handle_ingress(). This patch can now set the skb->mono_delivery_time to flag the skb->tstamp is used as the mono delivery_time (EDT) instead of the (rcv) timestamp and also clear it with skb_clear_delivery_time() after sch_handle_ingress(). This will make the bpf_redirect_*() to keep the mono delivery_time and used by a qdisc (fq) of the egress-ing interface. A latter patch will postpone the skb_clear_delivery_time() until the stack learns that the skb is being delivered locally and that will make other kernel forwarding paths (ip[6]_forward) able to keep the delivery_time also. Thus, like the previous patches on using the skb->mono_delivery_time bit, calling skb_clear_delivery_time() is not limited within the CONFIG_NET_INGRESS to avoid too many code churns among this set. Signed-off-by:
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Martin KaFai Lau authored
In __skb_tstamp_tx(), it may clone the egress skb and queues the clone to the sk_error_queue. The outgoing skb may have the mono delivery_time while the (rcv) timestamp is expected for the clone, so the skb->mono_delivery_time bit needs to be cleared from the clone. This patch adds the skb->mono_delivery_time clearing to the existing __net_timestamp() and use it in __skb_tstamp_tx(). The __net_timestamp() fast path usage in dev.c is changed to directly call ktime_get_real() since the mono_delivery_time bit is not set at that point. Signed-off-by:
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Martin KaFai Lau authored
A latter patch will set the skb->mono_delivery_time to flag the skb->tstamp is used as the mono delivery_time (EDT) instead of the (rcv) timestamp. skb_clear_tstamp() will then keep this delivery_time during forwarding. This patch is to make the network tapping (with af_packet) to handle the delivery_time stored in skb->tstamp. Regardless of tapping at the ingress or egress, the tapped skb is received by the af_packet socket, so it is ingress to the af_packet socket and it expects the (rcv) timestamp. When tapping at egress, dev_queue_xmit_nit() is used. It has already expected skb->tstamp may have delivery_time, so it does skb_clone()+net_timestamp_set() to ensure the cloned skb has the (rcv) timestamp before passing to the af_packet sk. This patch only adds to clear the skb->mono_delivery_time bit in net_timestamp_set(). When tapping at ingress, it currently expects the skb->tstamp is either 0 or the (rcv) timestamp. Meaning, the tapping at ingress path has already expected the skb->tstamp could be 0 and it will get the (rcv) timestamp by ktime_get_real() when needed. There are two cases for tapping at ingress: One case is af_packet queues the skb to its sk_receive_queue. The skb is either not shared or new clone created. The newly added skb_clear_delivery_time() is called to clear the delivery_time (if any) and set the (rcv) timestamp if needed before the skb is queued to the sk_receive_queue. Another case, the ingress skb is directly copied to the rx_ring and tpacket_get_timestamp() is used to get the (rcv) timestamp. The newly added skb_tstamp() is used in tpacket_get_timestamp() to check the skb->mono_delivery_time bit before returning skb->tstamp. As mentioned earlier, the tapping@ingress has already expected the skb may not have the (rcv) timestamp (because no sk has asked for it) and has handled this case by directly calling ktime_get_real(). Signed-off-by:
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Martin KaFai Lau authored
Right now, skb->tstamp is reset to 0 whenever the skb is forwarded. If skb->tstamp has the mono delivery_time, clearing it can hurt the performance when it finally transmits out to fq@phy-dev. The earlier patch added a skb->mono_delivery_time bit to flag the skb->tstamp carrying the mono delivery_time. This patch adds skb_clear_tstamp() helper which keeps the mono delivery_time and clears everything else. The delivery_time clearing will be postponed until the stack knows the skb will be delivered locally. It will be done in a latter patch. Signed-off-by:
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Martin KaFai Lau authored
skb->tstamp was first used as the (rcv) timestamp. The major usage is to report it to the user (e.g. SO_TIMESTAMP). Later, skb->tstamp is also set as the (future) delivery_time (e.g. EDT in TCP) during egress and used by the qdisc (e.g. sch_fq) to make decision on when the skb can be passed to the dev. Currently, there is no way to tell skb->tstamp having the (rcv) timestamp or the delivery_time, so it is always reset to 0 whenever forwarded between egress and ingress. While it makes sense to always clear the (rcv) timestamp in skb->tstamp to avoid confusing sch_fq that expects the delivery_time, it is a performance issue [0] to clear the delivery_time if the skb finally egress to a fq@phy-dev. For example, when forwarding from egress to ingress and then finally back to egress: tcp-sender => veth@netns => veth@hostns => fq@eth0@hostns ^ ^ reset rest This patch adds one bit skb->mono_delivery_time to flag the skb->tstamp is storing the mono delivery_time (EDT) instead of the (rcv) timestamp. The current use case is to keep the TCP mono delivery_time (EDT) and to be used with sch_fq. A latter patch will also allow tc-bpf@ingress to read and change the mono delivery_time. In the future, another bit (e.g. skb->user_delivery_time) can be added for the SCM_TXTIME where the clock base is tracked by sk->sk_clockid. [ This patch is a prep work. The following patches will get the other parts of the stack ready first. Then another patch after that will finally set the skb->mono_delivery_time. ] skb_set_delivery_time() function is added. It is used by the tcp_output.c and during ip[6] fragmentation to assign the delivery_time to the skb->tstamp and also set the skb->mono_delivery_time. A note on the change in ip_send_unicast_reply() in ip_output.c. It is only used by TCP to send reset/ack out of a ctl_sk. Like the new skb_set_delivery_time(), this patch sets the skb->mono_delivery_time to 0 for now as a place holder. It will be enabled in a latter patch. A similar case in tcp_ipv6 can be done with skb_set_delivery_time() in tcp_v6_send_response(). [0] (slide 22): https://linuxplumbersconf.org/event/11/contributions/953/attachments/867/1658/LPC_2021_BPF_Datapath_Extensions.pdfSigned-off-by: -
David S. Miller authored
Vladimir Oltean says: ==================== DSA unicast filtering This series doesn't attempt anything extremely brave, it just changes the way in which standalone ports which support FDB isolation work. Up until now, DSA has recommended that switch drivers configure standalone ports in a separate VID/FID with learning disabled, and with the CPU port as the only destination, reached trivially via flooding. That works, except that standalone ports will deliver all packets to the CPU. We can leverage the hardware FDB as a MAC DA filter, and disable flooding towards the CPU port, to force the dropping of packets with unknown MAC DA. We handle port promiscuity by re-enabling flooding towards the CPU port. This is relevant because the bridge puts its automatic (learning + flooding) ports in promiscuous mode, and this makes some things work automagically, like for example bridging with a foreign interface. We don't delve yet into the territory of managing CPU flooding more aggressively while under a bridge. The only switch driver that benefits from this work right now is the NXP LS1028A switch (felix). The others need to implement FDB isolation first, before DSA is going to install entries to the port's standalone database. Otherwise, these entries might collide with bridge FDB/MDB entries. This work was done mainly to have all the required features in place before somebody starts seriously architecting DSA support for multiple CPU ports. Otherwise it is much more difficult to bolt these features on top of multiple CPU ports. ==================== Signed-off-by: -
Vladimir Oltean authored
In order for the Felix DSA driver to be able to turn on/off flooding towards its CPU port, we need to redirect calls on the NPI port to actually act upon the index in the analyzer block that corresponds to the CPU port module. This was never necessary until now because DSA (or the bridge) never called ocelot_port_bridge_flags() for the NPI port. Signed-off-by:
Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by:
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Vladimir Oltean authored
felix_migrate_flood_to_tag_8021q_port() takes care of clearing the flooding bits on the old CPU port (which was the CPU port module), so manually clearing this bit from PGID_UC, PGID_MC, PGID_BC is redundant. Signed-off-by:
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Vladimir Oltean authored
The driver probes with all ports as standalone, and it supports unicast filtering. So DSA will call port_fdb_add() for all necessary addresses on the current CPU port. We also handle migrations when the CPU port hardware resource changes (on tagging protocol change), so there should not be any unknown address that we have to receive while not promiscuous. Signed-off-by:
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Vladimir Oltean authored
When the tagging protocol changes from "ocelot" to "ocelot-8021q" or in reverse, the DSA promiscuity setting that was applied for the old CPU port must be transferred to the new one. Signed-off-by:
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Vladimir Oltean authored
The "ocelot" and "ocelot-8021q" tagging protocols make use of different hardware resources, and host FDB entries have different destination ports in the switch analyzer module, practically speaking. So when the user requests a tagging protocol change, the driver must migrate all host FDB and MDB entries from the NPI port (in fact CPU port module) towards the same physical port, but this time used as a regular port. It is pointless for the felix driver to keep a copy of the host addresses, when we can create and export DSA helpers for walking through the addresses that it already needs to keep on the CPU port, for refcounting purposes. felix_classify_db() is moved up to avoid a forward declaration. We pass "bool change" because dp->fdbs and dp->mdbs are uninitialized lists when felix_setup() first calls felix_set_tag_protocol(), so we need to avoid calling dsa_port_walk_fdbs() during probe time. Signed-off-by:
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Vladimir Oltean authored
DSA can treat IFF_PROMISC and IFF_ALLMULTI on standalone user ports as signifying whether packets with an unknown MAC DA will be received or not. Since known MAC DAs are handled by FDB/MDB entries, this means that promiscuity is analogous to including/excluding the CPU port from the flood domain of those packets. There are two ways to signal CPU flooding to drivers. The first (chosen here) is to synthesize a call to ds->ops->port_bridge_flags() for the CPU port, with a mask of BR_FLOOD | BR_MCAST_FLOOD. This has the effect of turning on egress flooding on the CPU port regardless of source. The alternative would be to create a new ds->ops->port_host_flood() which is called per user port. Some switches (sja1105) have a flood domain that is managed per {ingress port, egress port} pair, so it would make more sense for this kind of switch to not flood the CPU from port A if just port B requires it. Nonetheless, the sja1105 has other quirks that prevent it from making use of unicast filtering, and without a concrete user making use of this feature, I chose not to implement it. Signed-off-by: -
Vladimir Oltean authored
To be able to safely turn off CPU flooding for standalone ports, we need to ensure that the dev_addr of each DSA slave interface is installed as a standalone host FDB entry for compatible switches. Signed-off-by:
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Vladimir Oltean authored
In preparation of disabling flooding towards the CPU in standalone ports mode, identify the addresses requested by upper interfaces and use the new API for DSA FDB isolation to request the hardware driver to offload these as FDB or MDB objects. The objects belong to the user port's database, and are installed pointing towards the CPU port. Because dev_uc_add()/dev_mc_add() is VLAN-unaware, we offload to the port standalone database addresses with VID 0 (also VLAN-unaware). So this excludes switches with global VLAN filtering from supporting unicast filtering, because there, it is possible for a port of a switch to join a VLAN-aware bridge, and this changes the VLAN awareness of standalone ports, requiring VLAN-aware standalone host FDB entries. For the same reason, hellcreek, which requires VLAN awareness in standalone mode, is also exempted from unicast filtering. We create "standalone" variants of dsa_port_host_fdb_add() and dsa_port_host_mdb_add() (and the _del coresponding functions). We also create a separate work item type for handling deferred standalone host FDB/MDB entries compared to the switchdev one. This is done for the purpose of clarity - the procedure for offloading a bridge FDB entry is different than offloading a standalone one, and the switchdev event work handles only FDBs anyway, not MDBs. Deferral is needed for standalone entries because ndo_set_rx_mode runs in atomic context. We could probably optimize things a little by first queuing up all entries that need to be offloaded, and scheduling the work item just once, but the data structures that we can pass through __dev_uc_sync() and __dev_mc_sync() are limiting (there is nothing like a void *priv), so we'd have to keep the list of queued events somewhere in struct dsa_switch, and possibly a lock for it. Too complicated for now. Adding the address to the master is handled by dev_uc_sync(), adding it to the hardware is handled by __dev_uc_sync(). So this is the reason why dsa_port_standalone_host_fdb_add() does not call dev_uc_add(). Not that it had the rtnl_mutex anyway - ndo_set_rx_mode has it, but is atomic. Signed-off-by:
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Vladimir Oltean authored
We are preparing to add API in port.c that adds FDB and MDB entries that correspond to the port's standalone database. Rename the existing methods to make it clear that the FDB and MDB entries offloaded come from the bridge database. Since the function names lengthen in dsa_slave_switchdev_event_work(), we place "addr" and "vid" in temporary variables, to shorten those. Signed-off-by:
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Vladimir Oltean authored
Lennert Buytenhek explains in commit df02c6ff ("dsa: fix master interface allmulti/promisc handling"), dated Nov 2008, that changing the promiscuity of interfaces that are down (here the master) is broken. This fact regarding promisc/allmulti has changed since commit b6c40d68 ("net: only invoke dev->change_rx_flags when device is UP") by Vlad Yasevich, dated Nov 2013. Therefore, DSA now has unnecessary complexity to handle master state transitions from down to up. In fact, syncing the unicast and multicast addresses can happen completely asynchronously to the administrative state changes. This change reduces that complexity by effectively fully reverting commit df02c6ff ("dsa: fix master interface allmulti/promisc handling"). Signed-off-by:
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Karol Kolacinski authored
Add a new ice_gnss.c file for holding the basic GNSS module functions. If the device supports GNSS module, call the new ice_gnss_init and ice_gnss_release functions where appropriate. Implement basic functionality for reading the data from GNSS module using TTY device. Add I2C read AQ command. It is now required for controlling the external physical connectors via external I2C port expander on E810-T adapters. Future changes will introduce write functionality. Signed-off-by:
Karol Kolacinski <karol.kolacinski@intel.com> Signed-off-by:
Sudhansu Sekhar Mishra <sudhansu.mishra@intel.com> Tested-by:
Sunitha Mekala <sunithax.d.mekala@intel.com> Signed-off-by:
Tony Nguyen <anthony.l.nguyen@intel.com> Signed-off-by:
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David S. Miller authored
Krzysztof Kozlowski says: ==================== nfc: llcp: few cleanups/improvements These are improvements, not fixing any experienced issue, just looking correct to me from the code point of view. Changes since v1 ================ 1. Split from the fix. Testing ======= Under QEMU only. The NFC/LLCP code was not really tested on a device. ==================== Signed-off-by: -
Krzysztof Kozlowski authored
This reverts commit 17f7ae16. The commit brought a new socket state LLCP_DISCONNECTING, which was never set, only read, so socket could never set to such state. Remove the dead code. Signed-off-by:
Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com> Signed-off-by:
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Krzysztof Kozlowski authored
nfc_llcp_sock_link() is called in all paths (bind/connect) as a last action, still protected with lock_sock(). When cleaning up in llcp_sock_release(), call nfc_llcp_sock_unlink() in a mirrored way: earlier and still under the lock_sock(). Signed-off-by:
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Krzysztof Kozlowski authored
Use test_bit() instead of open-coding it, just like in other places touching the bitmap. Signed-off-by:
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Krzysztof Kozlowski authored
Coding style encourages centralized exiting of functions, so rewrite llcp_sock_bind() error paths to use such pattern. This reduces the duplicated cleanup code, make success path visually shorter and also cleans up the errors in proper order (in reversed way from initialization). No functional impact expected. Signed-off-by:
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Krzysztof Kozlowski authored
The llcp_sock_connect() error paths were using a mixed way of central exit (goto) and cleanup Signed-off-by:
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Krzysztof Kozlowski authored
Nullify the llcp_sock->dev on llcp_sock_connect() error paths, symmetrically to the code llcp_sock_bind(). The non-NULL value of llcp_sock->dev is used in a few places to check whether the socket is still valid. There was no particular issue observed with missing NULL assignment in connect() error path, however a similar case - in the bind() error path - was triggereable. That one was fixed in commit 4ac06a1e ("nfc: fix NULL ptr dereference in llcp_sock_getname() after failed connect"), so the change here seems logical as well. Signed-off-by:
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David S. Miller authored
Ido Schimmel says: ==================== HW counters for soft devices Petr says: Offloading switch device drivers may be able to collect statistics of the traffic taking place in the HW datapath that pertains to a certain soft netdevice, such as a VLAN. In this patch set, add the necessary infrastructure to allow exposing these statistics to the offloaded netdevice in question, and add mlxsw offload. Across HW platforms, the counter itself very likely constitutes a limited resource, and the act of counting may have a performance impact. Therefore this patch set makes the HW statistics collection opt-in and togglable from userspace on a per-netdevice basis. Additionally, HW devices may have various limiting conditions under which they can realize the counter. Therefore it is also possible to query whether the requested counter is realized by any driver. In TC parlance, which is to a degree reused in this patch set, two values are recognized: "request" tracks whether the user enabled collecting HW statistics, and "used" tracks whether any HW statistics are actually collected. In the past, this author has expressed the opinion that `a typical user doing "ip -s l sh", including various scripts, wants to see the full picture and not worry what's going on where'. While that would be nice, unfortunately it cannot work: - Packets that trap from the HW datapath to the SW datapath would be double counted. For a given netdevice, some traffic can be purely a SW artifact, and some may flow through the HW object corresponding to the netdevice. But some traffic can also get trapped to the SW datapath after bumping the HW counter. It is not clear how to make sure double-counting does not occur in the SW datapath in that case, while still making sure that possibly divergent SW forwarding path gets bumped as appropriate. So simply adding HW and SW stats may work roughly, most of the time, but there are scenarios where the result is nonsensical. - HW devices will have limitations as to what type of traffic they can count. In case of mlxsw, which is part of this patch set, there is no reasonable way to count all traffic going through a certain netdevice, such as a VLAN netdevice enslaved to a bridge. It is however very simple to count traffic flowing through an L3 object, such as a VLAN netdevice with an IP address. Similarly for physical netdevices, the L3 object at which the counter is installed is the subport carrying untagged traffic. These are not "just counters". It is important that the user understands what is being counted. It would be incorrect to conflate these statistics with another existing statistics suite. To that end, this patch set introduces a statistics suite called "L3 stats". This label should make it easy to understand what is being counted, and to decide whether a given device can or cannot implement this suite for some type of netdevice. At the same time, the code is written to make future extensions easy, should a device pop up that can implement a different flavor of statistics suite (say L2, or an address-family-specific suite). For example, using a work-in-progress iproute2[1], to turn on and then list the counters on a VLAN netdevice: # ip stats set dev swp1.200 l3_stats on # ip stats show dev swp1.200 group offload subgroup l3_stats 56: swp1.200: group offload subgroup l3_stats on used on RX: bytes packets errors dropped missed mcast 0 0 0 0 0 0 TX: bytes packets errors dropped carrier collsns 0 0 0 0 0 0 The patchset progresses as follows: - Patch #1 is a cleanup. - In patch #2, remove the assumption that all LINK_OFFLOAD_XSTATS are dev-backed. The only attribute defined under the nest is currently IFLA_OFFLOAD_XSTATS_CPU_HIT. L3_STATS differs from CPU_HIT in that the driver that supplies the statistics is not the same as the driver that implements the netdevice. Make the code compatible with this in patch #2. - In patch #3, add the possibility to filter inside nests. The filter_mask field of RTM_GETSTATS header determines which top-level attributes should be included in the netlink response. This saves processing time by only including the bits that the user cares about instead of always dumping everything. This is doubly important for HW-backed statistics that would typically require a trip to the device to fetch the stats. In this patch, the UAPI is extended to allow filtering inside IFLA_STATS_LINK_OFFLOAD_XSTATS in particular, but the scheme is easily extensible to other nests as well. - In patch #4, propagate extack where we need it. In patch #5, make it possible to propagate errors from drivers to the user. - In patch #6, add the in-kernel APIs for keeping track of the new stats suite, and the notifiers that the core uses to communicate with the drivers. - In patch #7, add UAPI for obtaining the new stats suite. - In patch #8, add a new UAPI message, RTM_SETSTATS, which will carry the message to toggle the newly-added stats suite. In patch #9, add the toggle itself. At this point the core is ready for drivers to add support for the new stats suite. - In patches #10, #11 and #12, apply small tweaks to mlxsw code. - In patch #13, add support for L3 stats, which are realized as RIF counters. - Finally in patch #14, a selftest is added to the net/forwarding directory. Technically this is a HW-specific test, in that without a HW implementing the counters, it just will not pass. But devices that support L3 statistics at all are likely to be able to reuse this selftest, so it seems appropriate to put it in the general forwarding directory. We also have a netdevsim implementation, and a corresponding selftest that verifies specifically some of the core code. We intend to contribute these later. Interested parties can take a look at the raw code at [2]. [1] https://github.com/pmachata/iproute2/commits/soft_counters [2] https://github.com/pmachata/linux_mlxsw/commits/petrm_soft_counters_2 v2: - Patch #3: - Do not declare strict_start_type at the new policies, since they are used with nla_parse_nested() (sans _deprecated). - Use NLA_POLICY_NESTED to declare what the nest contents should be - Use NLA_POLICY_MASK instead of BITFIELD32 for the filtering attribute. - Patch #6: - s/monotonous/monotonic/ in commit message - Use a newly-added struct rtnl_hw_stats64 for stats transfer - Patch #7: - Use a newly-added struct rtnl_hw_stats64 for stats transfer - Patch #8: - Do not declare strict_start_type at the new policies, since they are used with nla_parse_nested() (sans _deprecated). - Patch #13: - Use a newly-added struct rtnl_hw_stats64 for stats transfer ==================== Signed-off-by: -
Petr Machata authored
Add a test that verifies operation of L3 HW statistics. Signed-off-by:
Petr Machata <petrm@nvidia.com> Signed-off-by:
Ido Schimmel <idosch@nvidia.com> Signed-off-by:
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Petr Machata authored
Spectrum machines support L3 stats by binding a counter to a RIF, a hardware object representing a router interface. Recognize the netdevice notifier events, NETDEV_OFFLOAD_XSTATS_*, to support enablement, disablement, and reporting back to core. As a netdevice gains a RIF, if L3 stats are enabled, install the counters, and ping the core so that a userspace notification can be emitted. Similarly, as a netdevice loses a RIF, push the as-yet-unreported statistics to the core, so that they are not lost, and ping the core to emit userspace notification. Signed-off-by:
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Petr Machata authored
Several more events are coming in the following patches, and extending the if statement is getting awkward. Instead, convert it to a switch. Signed-off-by:
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Petr Machata authored
The mlxsw_sp reference is carried by the mlxsw_sp_rif object that is passed to these functions as well. Just deduce the former from the latter, and drop the explicit mlxsw_sp parameter. Adapt callers. Signed-off-by:
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Petr Machata authored
The function mlxsw_reg_ritr_counter_pack() formats a register to configure a router interface (RIF) counter. The parameter `egress' determines whether an ingress or egress counter is to be configured. RITR, the register in question, has two sets of counter-related fields: one for ingress, one for egress. When setting values of the fields, the function sets the proper counter index field, but when setting the counter type, it always sets the egress field. Thus configuration of ingress counters is broken, and in fact an attempt to configure an ingress counter mangles a previously configured egress counter. This was never discovered, because there is currently no way to enable ingress counters on a router interface, only the egress one. Fix in an obvious way. Signed-off-by:
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Petr Machata authored
The offloaded HW stats are designed to allow per-netdevice enablement and disablement. Add an attribute, IFLA_STATS_SET_OFFLOAD_XSTATS_L3_STATS, which should be carried by the RTM_SETSTATS message, and expresses a desire to toggle L3 offload xstats on or off. As part of the above, add an exported function rtnl_offload_xstats_notify() that drivers can use when they have installed or deinstalled the counters backing the HW stats. At this point, it is possible to enable, disable and query L3 offload xstats on netdevices. (However there is no driver actually implementing these.) Signed-off-by:
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Petr Machata authored
The offloaded HW stats are designed to allow per-netdevice enablement and disablement. These stats are only accessible through RTM_GETSTATS, and therefore should be toggled by a RTM_SETSTATS message. Add it, and the necessary skeleton handler. Signed-off-by:
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Petr Machata authored
Add a new IFLA_STATS_LINK_OFFLOAD_XSTATS child attribute, IFLA_OFFLOAD_XSTATS_L3_STATS, to carry statistics for traffic that takes place in a HW router. The offloaded HW stats are designed to allow per-netdevice enablement and disablement. Additionally, as a netdevice is configured, it may become or cease being suitable for binding of a HW counter. Both of these aspects need to be communicated to the userspace. To that end, add another child attribute, IFLA_OFFLOAD_XSTATS_HW_S_INFO: - attr nest IFLA_OFFLOAD_XSTATS_HW_S_INFO - attr nest IFLA_OFFLOAD_XSTATS_L3_STATS - attr IFLA_OFFLOAD_XSTATS_HW_S_INFO_REQUEST - {0,1} as u8 - attr IFLA_OFFLOAD_XSTATS_HW_S_INFO_USED - {0,1} as u8 Thus this one attribute is a nest that can be used to carry information about various types of HW statistics, and indexing is very simply done by wrapping the information for a given statistics suite into the attribute that carries the suite is the RTM_GETSTATS query. At the same time, because _HW_S_INFO is nested directly below IFLA_STATS_LINK_OFFLOAD_XSTATS, it is possible through filtering to request only the metadata about individual statistics suites, without having to hit the HW to get the actual counters. Signed-off-by: -
Petr Machata authored
Offloading switch device drivers may be able to collect statistics of the traffic taking place in the HW datapath that pertains to a certain soft netdevice, such as VLAN. Add the necessary infrastructure to allow exposing these statistics to the offloaded netdevice in question. The API was shaped by the following considerations: - Collection of HW statistics is not free: there may be a finite number of counters, and the act of counting may have a performance impact. It is therefore necessary to allow toggling whether HW counting should be done for any particular SW netdevice. - As the drivers are loaded and removed, a particular device may get offloaded and unoffloaded again. At the same time, the statistics values need to stay monotonic (modulo the eventual 64-bit wraparound), increasing only to reflect traffic measured in the device. To that end, the netdevice keeps around a lazily-allocated copy of struct rtnl_link_stats64. Device drivers then contribute to the values kept therein at various points. Even as the driver goes away, the struct stays around to maintain the statistics values. - Different HW devices may be able to count different things. The motivation behind this patch in particular is exposure of HW counters on Nvidia Spectrum switches, where the only practical approach to counting traffic on offloaded soft netdevices currently is to use router interface counters, and count L3 traffic. Correspondingly that is the statistics suite added in this patch. Other devices may be able to measure different kinds of traffic, and for that reason, the APIs are built to allow uniform access to different statistics suites. - Because soft netdevices and offloading drivers are only loosely bound, a netdevice uses a notifier chain to communicate with the drivers. Several new notifiers, NETDEV_OFFLOAD_XSTATS_*, have been added to carry messages to the offloading drivers. - Devices can have various conditions for when a particular counter is available. As the device is configured and reconfigured, the device offload may become or cease being suitable for counter binding. A netdevice can use a notifier type NETDEV_OFFLOAD_XSTATS_REPORT_USED to ping offloading drivers and determine whether anyone currently implements a given statistics suite. This information can then be propagated to user space. When the driver decides to unoffload a netdevice, it can use a newly-added function, netdev_offload_xstats_report_delta(), to record outstanding collected statistics, before destroying the HW counter. This patch adds a helper, call_netdevice_notifiers_info_robust(), for dispatching a notifier with the possibility of unwind when one of the consumers bails. Given the wish to eventually get rid of the global notifier block altogether, this helper only invokes the per-netns notifier block. Signed-off-by:
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Petr Machata authored
Obtaining stats for the IFLA_STATS_LINK_OFFLOAD_XSTATS nest involves a HW access, and can fail for more reasons than just netlink message size exhaustion. Therefore do not always return -EMSGSIZE on the failure path, but respect the error code provided by the callee. Set the error explicitly where it is reasonable to assume -EMSGSIZE as the failure reason. Signed-off-by:
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Petr Machata authored
Later patches add handlers for more HW-backed statistics. An extack will be useful when communicating HW / driver errors to the client. Add the arguments as appropriate. Signed-off-by:
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Petr Machata authored
The filter_mask field of RTM_GETSTATS header determines which top-level attributes should be included in the netlink response. This saves processing time by only including the bits that the user cares about instead of always dumping everything. This is doubly important for HW-backed statistics that would typically require a trip to the device to fetch the stats. So far there was only one HW-backed stat suite per attribute. However, IFLA_STATS_LINK_OFFLOAD_XSTATS is a nest, and will gain a new stat suite in the following patches. It would therefore be advantageous to be able to filter within that nest, and select just one or the other HW-backed statistics suite. Extend rtnetlink so that RTM_GETSTATS permits attributes in the payload. The scheme is as follows: - RTM_GETSTATS - struct if_stats_msg - attr nest IFLA_STATS_GET_FILTERS - attr IFLA_STATS_LINK_OFFLOAD_XSTATS - u32 filter_mask This scheme reuses the existing enumerators by nesting them in a dedicated context attribute. This is covered by policies as usual, therefore a gradual opt-in is possible. Currently only IFLA_STATS_LINK_OFFLOAD_XSTATS nest has filtering enabled, because for the SW counters the issue does not seem to be that important. rtnl_offload_xstats_get_size() and _fill() are extended to observe the requested filters. Signed-off-by: -
Petr Machata authored
The IFLA_STATS_LINK_OFFLOAD_XSTATS attribute is a nest whose child attributes carry various special hardware statistics. The code that handles this nest was written with the idea that all these statistics would be exposed by the device driver of a physical netdevice. In the following patches, a new attribute is added to the abovementioned nest, which however can be defined for some soft netdevices. The NDO-based approach to querying these does not work, because it is not the soft netdevice driver that exposes these statistics, but an offloading NIC driver that does so. The current code does not scale well to this usage. Simply rewrite it back to the pattern seen in other fill-like and get_size-like functions elsewhere. Extract to helpers the code that is concerned with handling specifically NDO-backed statistics so that it can be easily reused should more such statistics be added. Signed-off-by:
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Petr Machata authored
The currently used names rtnl_get_offload_stats() and rtnl_get_offload_stats_size() do not clearly show the namespace. The former function additionally seems to have been named this way in accordance with the NDO name, as opposed to the naming used in the rtnetlink.c file (and indeed elsewhere in the netlink handling code). As more and differently-flavored attributes are introduced, a common clear prefix is needed for all related functions. Rename the functions to follow the rtnl_offload_xstats_* naming scheme. Signed-off-by:
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