If the MPTCP protocol is unable to create a new token,
the socket fallback to plain TCP, let's keep track
of such events via a specific MIB.
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Shannon Nelson says:
====================
ionic: add PTP and hw clock support
This patchset adds support for accessing the DSC hardware clock and
for offloading PTP timestamping.
Tx packet timestamping happens through a separate Tx queue set up with
expanded completion descriptors that can report the timestamp.
Rx timestamping can happen either on all queues, or on a separate
timestamping queue when specific filtering is requested. Again, the
timestamps are reported with the expanded completion descriptors.
The timestamping offload ability is advertised but not enabled until an
OS service asks for it. At that time the driver's queues are reconfigured
to use the different completion descriptors and the private processing
queues as needed.
Reading the raw clock value comes through a new pair of values in the
device info registers in BAR0. These high and low values are interpreted
with help from new clock mask, mult, and shift values in the device
identity information.
First we add the ability to detect new queue features, then the handling
of the new descriptor sizes. After adding the new interface structures,
we start adding the support code, saving the advertising to the stack
for last.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Let the network stack know we've got support for timestamping
the packets.
Signed-off-by: Allen Hubbe <allenbh@pensando.io>
Signed-off-by: Shannon Nelson <snelson@pensando.io>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add the new hwstamp stats to our ethtool stats output.
Signed-off-by: Allen Hubbe <allenbh@pensando.io>
Signed-off-by: Shannon Nelson <snelson@pensando.io>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add the get_ts_info() callback for ethtool support of
timestamping information.
Signed-off-by: Allen Hubbe <allenbh@pensando.io>
Signed-off-by: Shannon Nelson <snelson@pensando.io>
Signed-off-by: David S. Miller <davem@davemloft.net>
The Tx and Rx timestamped packets are handled through separate
queues. Here we set them up, service them, and tear them down
along with the normal Tx and Rx queues.
Signed-off-by: Allen Hubbe <allenbh@pensando.io>
Signed-off-by: Shannon Nelson <snelson@pensando.io>
Signed-off-by: David S. Miller <davem@davemloft.net>
We do hardware timestamping through a separate Tx queue,
and optionally through a separate Rx queue. These queues
are allocated, freed, and tracked separately from the basic
queue arrays.
Signed-off-by: Allen Hubbe <allenbh@pensando.io>
Signed-off-by: Shannon Nelson <snelson@pensando.io>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add handling of the new Rx packet classification filter type.
This simple bit of classification allows for steering packets
to a separate Rx queue for processing.
Signed-off-by: Allen Hubbe <allenbh@pensando.io>
Signed-off-by: Shannon Nelson <snelson@pensando.io>
Signed-off-by: David S. Miller <davem@davemloft.net>
These are changes to compile and link the new code, but no
new feature support is available or advertised yet.
Signed-off-by: Allen Hubbe <allenbh@pensando.io>
Signed-off-by: Shannon Nelson <snelson@pensando.io>
Signed-off-by: David S. Miller <davem@davemloft.net>
This adds the file of code for supporting Tx and Rx hardware
timestamps and the raw clock interface, but does not yet link
it in for compiling or use.
Signed-off-by: Allen Hubbe <allenbh@pensando.io>
Signed-off-by: Shannon Nelson <snelson@pensando.io>
Signed-off-by: David S. Miller <davem@davemloft.net>
Split the wait part out of adminq_post_wait() into a separate
function so that a caller can have finer grain control over
the sequencing of operations and locking.
Signed-off-by: Allen Hubbe <allenbh@pensando.io>
Signed-off-by: Shannon Nelson <snelson@pensando.io>
Signed-off-by: David S. Miller <davem@davemloft.net>
The interface for hardware timestamping includes a new FW
request, device identity fields, Tx and Rx queue feature bits, a
new Rx filter type, the beginnings of Rx packet classifications,
and hardware timestamp registers.
If the IONIC_ETH_HW_TIMESTAMP bit is shown in the
ionic_lif_config features bit string, then we have support
for the hw clock registers. If the IONIC_RXQ_F_HWSTAMP and
IONIC_TXQ_F_HWSTAMP features are shown in the ionic_q_identity
features, then the queues can support HW timestamps on packets.
Signed-off-by: Allen Hubbe <allenbh@pensando.io>
Signed-off-by: Shannon Nelson <snelson@pensando.io>
Signed-off-by: David S. Miller <davem@davemloft.net>
In preparating for hardware timestamping, we need to support
large Tx and Rx completion descriptors. Here we add the new
queue feature ids and handling for the completion descriptor
sizes.
We only are adding support for the Rx 2x sized completion
descriptors in the general Rx queues for now as we will be
using it for PTP Rx support, and we don't have an immediate
use for the large descriptors in the general Tx queues yet;
it will be used in a special Tx queues added in one of the
next few patches.
Signed-off-by: Allen Hubbe <allenbh@pensando.io>
Signed-off-by: Shannon Nelson <snelson@pensando.io>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add queue feature extensions to prepare for features that
can be queue specific, in addition to the general queue
features already defined. While we're here, change the
existing feature ids from #defines to enum.
Signed-off-by: Allen Hubbe <allenbh@pensando.io>
Signed-off-by: Shannon Nelson <snelson@pensando.io>
Signed-off-by: David S. Miller <davem@davemloft.net>
Alexei Starovoitov says:
====================
pull-request: bpf-next 2021-04-01
The following pull-request contains BPF updates for your *net-next* tree.
We've added 68 non-merge commits during the last 7 day(s) which contain
a total of 70 files changed, 2944 insertions(+), 1139 deletions(-).
The main changes are:
1) UDP support for sockmap, from Cong.
2) Verifier merge conflict resolution fix, from Daniel.
3) xsk selftests enhancements, from Maciej.
4) Unstable helpers aka kernel func calling, from Martin.
5) Batches ops for LPM map, from Pedro.
6) Fix race in bpf_get_local_storage, from Yonghong.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
All Gigabit PHYs use the same register layout as far as fetching
statistics goes. Fast Ethernet PHYs do not all support statistics, and
the BCM54616S would require some switching between the coper and fiber
modes to fetch the appropriate statistics which is not supported yet.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
If there is overlapp between ip_local_port_range and ip_local_reserved_ports with a huge reserved block, it will affect probability of selecting ephemeral ports, see file net/ipv4/inet_hashtables.c:723
int __inet_hash_connect(
...
for (i = 0; i < remaining; i += 2, port += 2) {
if (unlikely(port >= high))
port -= remaining;
if (inet_is_local_reserved_port(net, port))
continue;
E.g. if there is reserved block of 10000 ports, two ports right after this block will be 5000 more likely selected than others.
If this was intended, we can/should add note into documentation as proposed in this commit, otherwise we should think about different solution. One option could be mapping table of continuous port ranges. Second option could be letting user to modify step (port+=2) in above loop, e.g. using new sysctl parameter.
Signed-off-by: Otto Hollmann <otto.hollmann@suse.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix some typos.
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Lu Wei <luwei32@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
struct smc_clc_msg_local is declared twice. One is declared at
301st line. The blew one is not needed. Remove the duplicate.
Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
Acked-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
struct ctl_table_header is declared twice. One is declared
at 46th line. The blew one is not needed. Remove the duplicate.
Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The commit d2a029bde3 ("stmmac: pci: add MSI support for Intel Quark
X1000") introduced a pci_enable_msi() call in stmmac_pci.c.
With the commit 58da0cfa6c ("net: stmmac: create dwmac-intel.c to
contain all Intel platform"), Intel Quark platform related codes
have been moved to the newly created driver.
Removing this unnecessary pci_enable_msi() call as there are no other
devices that uses stmmac-pci and need MSI to be enabled.
Signed-off-by: Wong Vee Khee <vee.khee.wong@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Update dwmac-intel to use managed function, i.e. pcim_enable_device().
This will allow devres framework to call resource free function for us.
Signed-off-by: Wong Vee Khee <vee.khee.wong@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The logic in rt6_age_examine_exception is confusing. The commit is
to refactor the code.
Signed-off-by: Xu Jia <xujia39@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When enabling a bearer by name, we don't sanity check its name with
higher slot in bearer list. This may have the effect that the name
of an already enabled bearer bypasses the check.
To fix the above issue, we just perform an extra checking with all
existing bearers.
Fixes: cb30a63384 ("tipc: refactor function tipc_enable_bearer()")
Cc: stable@vger.kernel.org
Acked-by: Jon Maloy <jmaloy@redhat.com>
Signed-off-by: Hoang Le <hoang.h.le@dektech.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Tony Nguyen says:
====================
100GbE Intel Wired LAN Driver Updates 2021-03-31
This series contains updates to ice driver only.
Benita adds support for XPS.
Ani moves netdev registration to the end of probe to prevent use before
the interface is ready and moves up an error check to possibly avoid
an unneeded call. He also consolidates the VSI state and flag fields to
a single field.
Dan changes the segment where package information is pulled.
Paul S ensures correct ITR values are set when increasing ring size.
Paul G rewords a link misconfiguration message as this could be
expected.
Bruce removes setting an unnecessary AQ flag and corrects a memory
allocation call. Also fixes checkpatch issues for 'COMPLEX_MACRO'.
Qi aligns PTYPE bitmap naming by adding 'ptype' prefix to the bitmaps
missing it.
Brett removes limiting Rx queue mapping to RSS size as there is not a
dependency on this. He also refactors RSS configuration by introducing
individual functions for LUT and key configuration and by passing a
structure containing pertinent information instead of individual
arguments.
Tony corrects a comment block to follow netdev style.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Cong Wang says:
====================
From: Cong Wang <cong.wang@bytedance.com>
We have thousands of services connected to a daemon on every host
via AF_UNIX dgram sockets, after they are moved into VM, we have to
add a proxy to forward these communications from VM to host, because
rewriting thousands of them is not practical. This proxy uses an
AF_UNIX socket connected to services and a UDP socket to connect to
the host. It is inefficient because data is copied between kernel
space and user space twice, and we can not use splice() which only
supports TCP. Therefore, we want to use sockmap to do the splicing
without going to user-space at all (after the initial setup).
Currently sockmap only fully supports TCP, UDP is partially supported
as it is only allowed to add into sockmap. This patchset, as the second
part of the original large patchset, extends sockmap with:
1) cross-protocol support with BPF_SK_SKB_VERDICT; 2) full UDP support.
On the high level, ->read_sock() is required for each protocol to support
sockmap redirection, and in order to do sock proto update, a new ops
->psock_update_sk_prot() is introduced, which is also required. And the
BPF ->recvmsg() is also needed to replace the original ->recvmsg() to
retrieve skmsg. To make life easier, we have to get rid of lock_sock()
in sk_psock_handle_skb(), otherwise we would have to implement
->sendmsg_locked() on top of ->sendmsg(), which is ugly.
Please see each patch for more details.
To see the big picture, the original patchset is available here:
https://github.com/congwang/linux/tree/sockmap
this patchset is also available:
https://github.com/congwang/linux/tree/sockmap2
---
v8: get rid of 'offset' in udp_read_sock()
add checks for skb_verdict/stream_verdict conflict
add two cleanup patches for sock_map_link()
add a new test case
v7: use work_mutex to protect psock->work
return err in udp_read_sock()
add patch 6/13
clean up test case
v6: get rid of sk_psock_zap_ingress()
add rcu work patch
v5: use INDIRECT_CALL_2() for function pointers
use ingress_lock to fix a race condition found by Jacub
rename two helper functions
v4: get rid of lock_sock() in sk_psock_handle_skb()
get rid of udp_sendmsg_locked()
remove an empty line
update cover letter
v3: export tcp/udp_update_proto()
rename sk->sk_prot->psock_update_sk_prot()
improve changelogs
v2: separate from the original large patchset
rebase to the latest bpf-next
split UDP test case
move inet_csk_has_ulp() check to tcp_bpf.c
clean up udp_read_sock()
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Now UDP supports sockmap and redirection, we can safely update
the sock type checks for it accordingly.
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20210331023237.41094-15-xiyou.wangcong@gmail.com
We have to implement udp_bpf_recvmsg() to replace the ->recvmsg()
to retrieve skmsg from ingress_msg.
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20210331023237.41094-14-xiyou.wangcong@gmail.com
Although these two functions are only used by TCP, they are not
specific to TCP at all, both operate on skmsg and ingress_msg,
so fit in net/core/skmsg.c very well.
And we will need them for non-TCP, so rename and move them to
skmsg.c and export them to modules.
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210331023237.41094-13-xiyou.wangcong@gmail.com
This is similar to tcp_read_sock(), except we do not need
to worry about connections, we just need to retrieve skb
from UDP receive queue.
Note, the return value of ->read_sock() is unused in
sk_psock_verdict_data_ready(), and UDP still does not
support splice() due to lack of ->splice_read(), so users
can not reach udp_read_sock() directly.
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20210331023237.41094-12-xiyou.wangcong@gmail.com
Currently sockmap calls into each protocol to update the struct
proto and replace it. This certainly won't work when the protocol
is implemented as a module, for example, AF_UNIX.
Introduce a new ops sk->sk_prot->psock_update_sk_prot(), so each
protocol can implement its own way to replace the struct proto.
This also helps get rid of symbol dependencies on CONFIG_INET.
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210331023237.41094-11-xiyou.wangcong@gmail.com
Reusing BPF_SK_SKB_STREAM_VERDICT is possible but its name is
confusing and more importantly we still want to distinguish them
from user-space. So we can just reuse the stream verdict code but
introduce a new type of eBPF program, skb_verdict. Users are not
allowed to attach stream_verdict and skb_verdict programs to the
same map.
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20210331023237.41094-10-xiyou.wangcong@gmail.com
sock_map_link() passes down map progs, but it is confusing
to see both map progs and psock progs. Make the map progs
more obvious by retrieving it directly with sock_map_progs()
inside sock_map_link(). Now it is aligned with
sock_map_link_no_progs() too.
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20210331023237.41094-8-xiyou.wangcong@gmail.com
The RCU callback sk_psock_destroy() only queues work psock->gc,
so we can just switch to rcu work to simplify the code.
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20210331023237.41094-6-xiyou.wangcong@gmail.com
We do not have to lock the sock to avoid losing sk_socket,
instead we can purge all the ingress queues when we close
the socket. Sending or receiving packets after orphaning
socket makes no sense.
We do purge these queues when psock refcnt reaches zero but
here we want to purge them explicitly in sock_map_close().
There are also some nasty race conditions on testing bit
SK_PSOCK_TX_ENABLED and queuing/canceling the psock work,
we can expand psock->ingress_lock a bit to protect them too.
As noticed by John, we still have to lock the psock->work,
because the same work item could be running concurrently on
different CPU's.
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20210331023237.41094-5-xiyou.wangcong@gmail.com
We only have skb_send_sock_locked() which requires callers
to use lock_sock(). Introduce a variant skb_send_sock()
which locks on its own, callers do not need to lock it
any more. This will save us from adding a ->sendmsg_locked
for each protocol.
To reuse the code, pass function pointers to __skb_send_sock()
and build skb_send_sock() and skb_send_sock_locked() on top.
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com>
Link: https://lore.kernel.org/bpf/20210331023237.41094-4-xiyou.wangcong@gmail.com
Currently we rely on lock_sock to protect ingress_msg,
it is too big for this, we can actually just use a spinlock
to protect this list like protecting other skb queues.
__tcp_bpf_recvmsg() is still special because of peeking,
it still has to use lock_sock.
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Jakub Sitnicki <jakub@cloudflare.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20210331023237.41094-3-xiyou.wangcong@gmail.com
Currently we purge the ingress_skb queue only when psock
refcnt goes down to 0, so locking the queue is not necessary,
but in order to be called during ->close, we have to lock it
here.
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Jakub Sitnicki <jakub@cloudflare.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20210331023237.41094-2-xiyou.wangcong@gmail.com
SO_TXTIME hardware offload requires testing across devices, either
between machines or separate network namespaces.
Split up SO_TXTIME test into tx and rx modes, so traffic can be
sent from one process to another. Create a veth-pair on different
namespaces and bind each process to an end point via [-S]ource and
[-D]estination parameters. Optional start [-t]ime parameter can be
passed to synchronize the test across the hosts (with synchorinzed
clocks).
Signed-off-by: Carlos Llamas <cmllamas@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
mt7623 uses offload version 2 too
tested on Bananapi-R2
Signed-off-by: Frank Wunderlich <frank-w@public-files.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Turn on the MEEAO field of MTL_ECC_Control_Register by default.
As the MTL ECC Error Address Status Over-ride(MEEAO) is set by default,
the following error address fields will hold the last valid address
where the error is detected.
Signed-off-by: Voon Weifeng <weifeng.voon@intel.com>
Signed-off-by: Tan Tee Min <tee.min.tan@intel.com>
Co-developed-by: Wong Vee Khee <vee.khee.wong@linux.intel.com>
Signed-off-by: Wong Vee Khee <vee.khee.wong@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Vladimir Oltean says:
====================
XDP for NXP ENETC
This series adds support to the enetc driver for the basic XDP primitives.
The ENETC is a network controller found inside the NXP LS1028A SoC,
which is a dual-core Cortex A72 device for industrial networking,
with the CPUs clocked at up to 1.3 GHz. On this platform, there are 4
ENETC ports and a 6-port embedded DSA switch, in a topology that looks
like this:
+-------------------------------------------------------------------------+
| +--------+ 1 Gbps (typically disabled) |
| ENETC PCI | ENETC |--------------------------+ |
| Root Complex | port 3 |-----------------------+ | |
| Integrated +--------+ | | |
| Endpoint | | |
| +--------+ 2.5 Gbps | | |
| | ENETC |--------------+ | | |
| | port 2 |-----------+ | | | |
| +--------+ | | | | |
| | | | | |
| +------------------------------------------------+
| | | Felix | | Felix | |
| | Switch | port 4 | | port 5 | |
| | +--------+ +--------+ |
| | |
| +--------+ +--------+ | +--------+ +--------+ +--------+ +--------+ |
| | ENETC | | ENETC | | | Felix | | Felix | | Felix | | Felix | |
| | port 0 | | port 1 | | | port 0 | | port 1 | | port 2 | | port 3 | |
+-------------------------------------------------------------------------+
| | | | | |
v v v v v v
Up to Up to Up to 4x 2.5Gbps
2.5Gbps 1Gbps
The ENETC ports 2 and 3 can act as DSA masters for the embedded switch.
Because 4 out of the 6 externally-facing ports of the SoC are switch
ports, the most interesting use case for XDP on this device is in fact
XDP_TX on the 2.5Gbps DSA master.
Nonetheless, the results presented below are for IPv4 forwarding between
ENETC port 0 (eno0) and port 1 (eno1) both configured for 1Gbps.
There are two streams of IPv4/UDP datagrams with a frame length of 64
octets delivered at 100% port load to eno0 and to eno1. eno0 has a flow
steering rule to process the traffic on RX ring 0 (CPU 0), and eno1 has
a flow steering rule towards RX ring 1 (CPU 1).
For the IPFWD test, standard IP routing was enabled in the netns.
For the XDP_DROP test, the samples/bpf/xdp1 program was attached to both
eno0 and to eno1.
For the XDP_TX test, the samples/bpf/xdp2 program was attached to both
eno0 and to eno1.
For the XDP_REDIRECT test, the samples/bpf/xdp_redirect program was
attached once to the input of eno0/output of eno1, and twice to the
input of eno1/output of eno0.
Finally, the preliminary results are as follows:
| IPFWD | XDP_TX | XDP_REDIRECT | XDP_DROP
--------+-------+--------+-------------------------
fps | 761 | 2535 | 1735 | 2783
Gbps | 0.51 | 1.71 | 1.17 | n/a
There is a strange phenomenon in my testing sistem where it appears that
one CPU is processing more than the other. I have not investigated this
too much. Also, the code might not be very well optimized (for example
dma_sync_for_device is called with the full ENETC_RXB_DMA_SIZE_XDP).
Design wise, the ENETC is a PCI device with BD rings, so it uses the
MEM_TYPE_PAGE_SHARED memory model, as can typically be seen in Intel
devices. The strategy was to build upon the existing model that the
driver uses, and not change it too much. So you will see things like a
separate NAPI poll function for XDP.
I have only tested with PAGE_SIZE=4096, and since we split pages in
half, it means that MTU-sized frames are scatter/gather (the XDP
headroom + skb_shared_info only leaves us 1476 bytes of data per
buffer). This is sub-optimal, but I would rather keep it this way and
help speed up Lorenzo's series for S/G support through testing, rather
than change the enetc driver to use some other memory model like page_pool.
My code is already structured for S/G, and that works fine for XDP_DROP
and XDP_TX, just not for XDP_REDIRECT, even between two enetc ports.
So the S/G XDP_REDIRECT is stubbed out (the frames are dropped), but
obviously I would like to remove that limitation soon.
Please note that I am rather new to this kind of stuff, I am more of a
control path person, so I would appreciate feedback.
Enough talking, on to the patches.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
The driver implementation of the XDP_REDIRECT action reuses parts from
XDP_TX, most notably the enetc_xdp_tx function which transmits an array
of TX software BDs. Only this time, the buffers don't have DMA mappings,
we need to create them.
When a BPF program reaches the XDP_REDIRECT verdict for a frame, we can
employ the same buffer reuse strategy as for the normal processing path
and for XDP_PASS: we can flip to the other page half and seed that to
the RX ring.
Note that scatter/gather support is there, but disabled due to lack of
multi-buffer support in XDP (which is added by this series):
https://patchwork.kernel.org/project/netdevbpf/cover/cover.1616179034.git.lorenzo@kernel.org/
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As explained in the XDP_TX patch, when receiving a burst of frames with
the XDP_TX verdict, there is a momentary dip in the number of available
RX buffers. The system will eventually recover as TX completions will
start kicking in and refilling our RX BD ring again. But until that
happens, we need to survive with as few out-of-buffer discards as
possible.
This increases the memory footprint of the driver in order to avoid
discards at 2.5Gbps line rate 64B packet sizes, the maximum speed
available for testing on 1 port on NXP LS1028A.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
