Commit Graph

310 Commits

Author SHA1 Message Date
Björn Töpel 411dc16ff1 i40e: clean zero-copy XDP Rx ring on shutdown/reset
Outstanding Rx descriptors are temporarily stored on a stash/reuse
queue. When/if the HW rings comes up again, entries from the stash are
used to re-populate the ring.

The latter required some restructuring of the allocation scheme for
the AF_XDP zero-copy implementation. There is now a fast, and a slow
allocation. The "fast allocation" is used from the fast-path and
obtains free buffers from the fill ring and the internal recycle
mechanism. The "slow allocation" is only used in ring setup, and
obtains buffers from the fill ring and the stash (if any).

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2018-09-25 13:15:16 -07:00
Björn Töpel 9dbb137045 i40e: clean zero-copy XDP Tx ring on shutdown/reset
When the zero-copy enabled XDP Tx ring is torn down, due to
configuration changes, outstanding frames on the hardware descriptor
ring are queued on the completion ring.

The completion ring has a back-pressure mechanism that will guarantee
that there is sufficient space on the ring.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2018-09-25 13:10:24 -07:00
Magnus Karlsson 1328dcddbd i40e: add AF_XDP zero-copy Tx support
This patch adds zero-copy Tx support for AF_XDP sockets. It implements
the ndo_xsk_async_xmit netdev ndo and performs all the Tx logic from a
NAPI context. This means pulling egress packets from the Tx ring,
placing the frames on the NIC HW descriptor ring and completing sent
frames back to the application via the completion ring.

The regular XDP Tx ring is used for AF_XDP as well. This rationale for
this is as follows: XDP_REDIRECT guarantees mutual exclusion between
different NAPI contexts based on CPU id. In other words, a netdev can
XDP_REDIRECT to another netdev with a different NAPI context, since
the operation is bound to a specific core and each core has its own
hardware ring.

As the AF_XDP Tx action is running in the same NAPI context and using
the same ring, it will also be protected from XDP_REDIRECT actions
with the exact same mechanism.

As with AF_XDP Rx, all AF_XDP Tx specific functions are added to
i40e_xsk.c.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-08-29 12:25:53 -07:00
Magnus Karlsson a96e747273 i40e: move common Tx functions to i40e_txrx_common.h
This patch prepares for the upcoming zero-copy Tx functionality, by
moving common functions and refactor chunks of code into re-usable
functions, used both by the regular path and zero-copy path.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-08-29 12:25:53 -07:00
Björn Töpel 0a714186d3 i40e: add AF_XDP zero-copy Rx support
This patch adds zero-copy Rx support for AF_XDP sockets. Instead of
allocating buffers of type MEM_TYPE_PAGE_SHARED, the Rx frames are
allocated as MEM_TYPE_ZERO_COPY when AF_XDP is enabled for a certain
queue.

All AF_XDP specific functions are added to a new file, i40e_xsk.c.

Note that when AF_XDP zero-copy is enabled, the XDP action XDP_PASS
will allocate a new buffer and copy the zero-copy frame prior passing
it to the kernel stack.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-08-29 12:25:53 -07:00
Björn Töpel 20a739dbef i40e: move common Rx functions to i40e_txrx_common.h
This patch prepares for the upcoming zero-copy Rx functionality, by
moving/changing linkage of common functions, used both by the regular
path and zero-copy path.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-08-29 12:25:53 -07:00
Björn Töpel 6d7aad1da2 i40e: refactor Rx path for re-use
In this commit, the Rx path is refactored some, as a step torwards the
introduction AF_XDP Rx zero-copy.

The page re-use counter is moved into the i40e_reuse_rx_page, instead
of bumping the counter in many places. The Rx buffer page clearing is
moved for better readability. Lastely, functions to update statistics
and bump the XDP Tx ring are introduced.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-08-29 12:25:53 -07:00
Gustavo A. R. Silva f7c3ca2da4 i40e_txrx: mark expected switch fall-through
In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

Addresses-Coverity-ID: 114791 ("Missing break in switch")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-07 17:54:20 -07:00
Jesper Dangaard Brouer 2e68931238 i40e: split XDP_TX tail and XDP_REDIRECT map flushing
The driver was combining the XDP_TX tail flush and XDP_REDIRECT
map flushing (xdp_do_flush_map).  This is suboptimal, these two
flush operations should be kept separate.

It looks like the mistake was copy-pasted from ixgbe.

Fixes: d9314c474d ("i40e: add support for XDP_REDIRECT")
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-28 14:27:52 +09:00
Daniel Borkmann c51818d5b7 bpf, xdp, i40e: fix i40e_build_skb skb reserve and truesize
Using skb_reserve(skb, I40E_SKB_PAD + (xdp->data - xdp->data_hard_start))
is clearly wrong since I40E_SKB_PAD already points to the offset where
the original xdp->data was sitting since xdp->data_hard_start is defined
as xdp->data - i40e_rx_offset(rx_ring) where latter offsets to I40E_SKB_PAD
when build skb is used.

However, also before cc5b114dcf ("bpf, i40e: add meta data support")
this seems broken since bpf_xdp_adjust_head() helper could have been used
to alter headroom and enlarge / shrink the frame and with that the assumption
that the xdp->data remains unchanged does not hold and would push a bogus
packet to upper stack.

ixgbe got this right in 9247080816 ("ixgbe: add XDP support for pass and
drop actions"). In any case, fix it by removing the I40E_SKB_PAD from both
skb_reserve() and truesize calculation.

Fixes: cc5b114dcf ("bpf, i40e: add meta data support")
Fixes: 0c8493d90b ("i40e: add XDP support for pass and drop actions")
Reported-by: Keith Busch <keith.busch@linux.intel.com>
Reported-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Björn Töpel <bjorn.topel@intel.com>
Cc: John Fastabend <john.fastabend@gmail.com>
Tested-by: Keith Busch <keith.busch@linux.intel.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-20 07:24:28 +09:00
David S. Miller fd129f8941 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2018-06-05

The following pull-request contains BPF updates for your *net-next* tree.

The main changes are:

1) Add a new BPF hook for sendmsg similar to existing hooks for bind and
   connect: "This allows to override source IP (including the case when it's
   set via cmsg(3)) and destination IP:port for unconnected UDP (slow path).
   TCP and connected UDP (fast path) are not affected. This makes UDP support
   complete, that is, connected UDP is handled by connect hooks, unconnected
   by sendmsg ones.", from Andrey.

2) Rework of the AF_XDP API to allow extending it in future for type writer
   model if necessary. In this mode a memory window is passed to hardware
   and multiple frames might be filled into that window instead of just one
   that is the case in the current fixed frame-size model. With the new
   changes made this can be supported without having to add a new descriptor
   format. Also, core bits for the zero-copy support for AF_XDP have been
   merged as agreed upon, where i40e bits will be routed via Jeff later on.
   Various improvements to documentation and sample programs included as
   well, all from Björn and Magnus.

3) Given BPF's flexibility, a new program type has been added to implement
   infrared decoders. Quote: "The kernel IR decoders support the most
   widely used IR protocols, but there are many protocols which are not
   supported. [...] There is a 'long tail' of unsupported IR protocols,
   for which lircd is need to decode the IR. IR encoding is done in such
   a way that some simple circuit can decode it; therefore, BPF is ideal.
   [...] user-space can define a decoder in BPF, attach it to the rc
   device through the lirc chardev.", from Sean.

4) Several improvements and fixes to BPF core, among others, dumping map
   and prog IDs into fdinfo which is a straight forward way to correlate
   BPF objects used by applications, removing an indirect call and therefore
   retpoline in all map lookup/update/delete calls by invoking the callback
   directly for 64 bit archs, adding a new bpf_skb_cgroup_id() BPF helper
   for tc BPF programs to have an efficient way of looking up cgroup v2 id
   for policy or other use cases. Fixes to make sure we zero tunnel/xfrm
   state that hasn't been filled, to allow context access wrt pt_regs in
   32 bit archs for tracing, and last but not least various test cases
   for fixes that landed in bpf earlier, from Daniel.

5) Get rid of the ndo_xdp_flush API and extend the ndo_xdp_xmit with
   a XDP_XMIT_FLUSH flag instead which allows to avoid one indirect
   call as flushing is now merged directly into ndo_xdp_xmit(), from Jesper.

6) Add a new bpf_get_current_cgroup_id() helper that can be used in
   tracing to retrieve the cgroup id from the current process in order
   to allow for e.g. aggregation of container-level events, from Yonghong.

7) Two follow-up fixes for BTF to reject invalid input values and
   related to that also two test cases for BPF kselftests, from Martin.

8) Various API improvements to the bpf_fib_lookup() helper, that is,
   dropping MPLS bits which are not fully hashed out yet, rejecting
   invalid helper flags, returning error for unsupported address
   families as well as renaming flowlabel to flowinfo, from David.

9) Various fixes and improvements to sockmap BPF kselftests in particular
   in proper error detection and data verification, from Prashant.

10) Two arm32 BPF JIT improvements. One is to fix imm range check with
    regards to whether immediate fits into 24 bits, and a naming cleanup
    to get functions related to rsh handling consistent to those handling
    lsh, from Wang.

11) Two compile warning fixes in BPF, one for BTF and a false positive
    to silent gcc in stack_map_get_build_id_offset(), from Arnd.

12) Add missing seg6.h header into tools include infrastructure in order
    to fix compilation of BPF kselftests, from Mathieu.

13) Several formatting cleanups in the BPF UAPI helper description that
    also fix an error during rst2man compilation, from Quentin.

14) Hide an unused variable in sk_msg_convert_ctx_access() when IPv6 is
    not built into the kernel, from Yue.

15) Remove a useless double assignment in dev_map_enqueue(), from Colin.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-05 12:42:19 -04:00
Jesper Dangaard Brouer 763ea096f3 i40e: remove ndo_xdp_flush call i40e_xdp_flush
Remove the ndo_xdp_flush call implementation i40e_xdp_flush
as no callers of ndo_xdp_flush are left.

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-06-05 14:03:15 +02:00
Daniel Borkmann cc5b114dcf bpf, i40e: add meta data support
Add support for XDP meta data when using build skb variant of
the i40e driver. Implementation is analogous to the existing
ixgbe and ixgbevf support for meta data from 366a88fe2f ("bpf,
ixgbe: add meta data support") and be8333322e ("ixgbevf: Add
support for meta data"). With the build skb variant we get
192 bytes of extra headroom which can be used for encaps or
meta data.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Tested-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2018-06-04 10:23:58 -07:00
Jesper Dangaard Brouer cdb57ed07f i40e: implement flush flag for ndo_xdp_xmit
When passed the XDP_XMIT_FLUSH flag i40e_xdp_xmit now performs the
same kind of ring tail update as in i40e_xdp_flush.  The advantage is
that all the necessary checks have been performed and xdp_ring can be
updated, instead of having to perform the exact same steps/checks in
i40e_xdp_flush

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-06-03 08:11:34 -07:00
Jesper Dangaard Brouer 42b3346898 xdp: add flags argument to ndo_xdp_xmit API
This patch only change the API and reject any use of flags. This is an
intermediate step that allows us to implement the flush flag operation
later, for each individual driver in a separate patch.

The plan is to implement flush operation via XDP_XMIT_FLUSH flag
and then remove XDP_XMIT_FLAGS_NONE when done.

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-06-03 08:11:34 -07:00
Jesper Dangaard Brouer 735fc4054b xdp: change ndo_xdp_xmit API to support bulking
This patch change the API for ndo_xdp_xmit to support bulking
xdp_frames.

When kernel is compiled with CONFIG_RETPOLINE, XDP sees a huge slowdown.
Most of the slowdown is caused by DMA API indirect function calls, but
also the net_device->ndo_xdp_xmit() call.

Benchmarked patch with CONFIG_RETPOLINE, using xdp_redirect_map with
single flow/core test (CPU E5-1650 v4 @ 3.60GHz), showed
performance improved:
 for driver ixgbe: 6,042,682 pps -> 6,853,768 pps = +811,086 pps
 for driver i40e : 6,187,169 pps -> 6,724,519 pps = +537,350 pps

With frames avail as a bulk inside the driver ndo_xdp_xmit call,
further optimizations are possible, like bulk DMA-mapping for TX.

Testing without CONFIG_RETPOLINE show the same performance for
physical NIC drivers.

The virtual NIC driver tun sees a huge performance boost, as it can
avoid doing per frame producer locking, but instead amortize the
locking cost over the bulk.

V2: Fix compile errors reported by kbuild test robot <lkp@intel.com>
V4: Isolated ndo, driver changes and callers.

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-24 18:36:15 -07:00
Jacob Keller f5254429e1 i40e/i40evf: cleanup incorrect function doxygen comments
Recent versions of the Linux kernel now warn about incorrect parameter
definitions for function comments. Fix up several function comments to
correctly reflect the current function arguments. This cleans up the
warnings and helps ensure our documentation is accurate.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2018-04-30 09:09:04 -07:00
Jeff Kirsher 51dce24bcd net: intel: Cleanup the copyright/license headers
After many years of having a ~30 line copyright and license header to our
source files, we are finally able to reduce that to one line with the
advent of the SPDX identifier.

Also caught a few files missing the SPDX license identifier, so fixed
them up.

Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Acked-by: Shannon Nelson <shannon.nelson@oracle.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 14:00:04 -04:00
Jesper Dangaard Brouer 44fa2dbd47 xdp: transition into using xdp_frame for ndo_xdp_xmit
Changing API ndo_xdp_xmit to take a struct xdp_frame instead of struct
xdp_buff.  This brings xdp_return_frame and ndp_xdp_xmit in sync.

This builds towards changing the API further to become a bulk API,
because xdp_buff is not a queue-able object while xdp_frame is.

V4: Adjust for commit 59655a5b6c ("tuntap: XDP_TX can use native XDP")
V7: Adjust for commit d9314c474d ("i40e: add support for XDP_REDIRECT")

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-17 10:50:30 -04:00
Jesper Dangaard Brouer 039930945a xdp: transition into using xdp_frame for return API
Changing API xdp_return_frame() to take struct xdp_frame as argument,
seems like a natural choice. But there are some subtle performance
details here that needs extra care, which is a deliberate choice.

When de-referencing xdp_frame on a remote CPU during DMA-TX
completion, result in the cache-line is change to "Shared"
state. Later when the page is reused for RX, then this xdp_frame
cache-line is written, which change the state to "Modified".

This situation already happens (naturally) for, virtio_net, tun and
cpumap as the xdp_frame pointer is the queued object.  In tun and
cpumap, the ptr_ring is used for efficiently transferring cache-lines
(with pointers) between CPUs. Thus, the only option is to
de-referencing xdp_frame.

It is only the ixgbe driver that had an optimization, in which it can
avoid doing the de-reference of xdp_frame.  The driver already have
TX-ring queue, which (in case of remote DMA-TX completion) have to be
transferred between CPUs anyhow.  In this data area, we stored a
struct xdp_mem_info and a data pointer, which allowed us to avoid
de-referencing xdp_frame.

To compensate for this, a prefetchw is used for telling the cache
coherency protocol about our access pattern.  My benchmarks show that
this prefetchw is enough to compensate the ixgbe driver.

V7: Adjust for commit d9314c474d ("i40e: add support for XDP_REDIRECT")
V8: Adjust for commit bd658dda42 ("net/mlx5e: Separate dma base address
and offset in dma_sync call")

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-17 10:50:29 -04:00
Jesper Dangaard Brouer b411ef1102 i40e: convert to use generic xdp_frame and xdp_return_frame API
Also convert driver i40e, which very recently got XDP_REDIRECT support
in commit d9314c474d ("i40e: add support for XDP_REDIRECT").

V7: This patch got added in V7 of this patchset.

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-17 10:50:28 -04:00
Björn Töpel d9314c474d i40e: add support for XDP_REDIRECT
The driver now acts upon the XDP_REDIRECT return action. Two new ndos
are implemented, ndo_xdp_xmit and ndo_xdp_flush.

XDP_REDIRECT action enables XDP program to redirect frames to other
netdevs.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2018-03-26 14:17:10 -07:00
Björn Töpel 8ce29c679a i40e: tweak page counting for XDP_REDIRECT
This commit tweaks the page counting for XDP_REDIRECT to function
properly. XDP_REDIRECT support will be added in a future commit.

The current page counting scheme assumes that the reference count
cannot decrease until the received frame is sent to the upper layers
of the networking stack. This assumption does not hold for the
XDP_REDIRECT action, since a page (pointed out by xdp_buff) can have
its reference count decreased via the xdp_do_redirect call.

To work around that, we now start off by a large page count and then
don't allow a refcount less than two.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2018-03-26 14:10:04 -07:00
Jacob Keller 134201aead i40e: move AUTO_DISABLED flags into the state field
The two Flow Directory auto disable flags are used at run time to mark
when the flow director features needed to be disabled. Thus the flags
could change even when the RTNL lock is not held.

They also have some code constructions which really should be
test_and_set or test_and_clear using atomic bit operations.

Create new state fields to mark this, and stop including them in
pf->flags.

This is part of a larger effort to remove the need for cmpxchg64 in
i40e_set_priv_flags().

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2018-03-26 13:46:30 -07:00
Jeff Kirsher ae06c70b13 intel: add SPDX identifiers to all the Intel drivers
Add the SPDX identifiers to all the Intel wired LAN driver files, as
outlined in Documentation/process/license-rules.rst.

Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-23 12:18:21 -04:00
Alan Brady 04d4105174 i40e/i40evf: use SW variables for hang detection
The i40e_detect_recover_hung function uses the i40e_get_tx_pending
function to determine if there are packets stalled on the ring.
i40e_get_tx_pending calculates the pending packets using the head
writeback value and HW tail.  If the queue is stopped and we lose the
interrupt to update our next_to_clean then we a) won't get another
interrupt to clean because queue is stopped b) we won't catch the
problem with i40e_detect_recover_hung because the HW values look like
there's no packets waiting to be transmitted.  Using the SW values we
can catch the issue because next_to_clean will be out of sync with head
writeback.

This has the added benefit being less CPU intensive because we don't
need to reach into the hardware to get the values.

Signed-off-by: Alan Brady <alan.brady@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2018-02-26 12:33:27 -08:00
Alexander Duyck a0073a4b8b i40e/i40evf: Add support for new mechanism of updating adaptive ITR
This patch replaces the existing mechanism for determining the correct
value to program for adaptive ITR with yet another new and more
complicated approach.

The basic idea from a 30K foot view is that this new approach will push the
Rx interrupt moderation up so that by default it starts in low latency and
is gradually pushed up into a higher latency setup as long as doing so
increases the number of packets processed, if the number of packets drops
to 4 to 1 per packet we will reset and just base our ITR on the size of the
packets being received. For Tx we leave it floating at a high interrupt
delay and do not pull it down unless we start processing more than 112
packets per interrupt. If we start exceeding that we will cut our interrupt
rates in half until we are back below 112.

The side effect of these patches are that we will be processing more
packets per interrupt. This is both a good and a bad thing as it means we
will not be blocking processing in the case of things like pktgen and XDP,
but we will also be consuming a bit more CPU in the cases of things such as
network throughput tests using netperf.

One delta from this versus the ixgbe version of the changes is that I have
made the interrupt moderation a bit more aggressive when we are in bulk
mode by moving our "goldilocks zone" up from 48 to 96 to 56 to 112. The
main motivation behind moving this is to address the fact that we need to
update less frequently, and have more fine grained control due to the
separate Tx and Rx ITR times.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2018-02-12 11:50:10 -08:00
Alexander Duyck 556fdfd6e6 i40e/i40evf: Split container ITR into current_itr and target_itr
This patch is mostly prep-work for replacing the current approach to
programming the dynamic aka adaptive ITR. Specifically here what we are
doing is splitting the Tx and Rx ITR each into two separate values.

The first value current_itr represents the current value of the register.

The second value target_itr represents the desired value of the register.

The general plan by doing this is to allow for deferring the update of the
ITR value under certain circumstances. For now we will work with what we
have, but in the future I hope to change the behavior so that we always
only update one ITR at a time using some simple logic to determine which
ITR requires an update.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2018-02-12 11:43:50 -08:00
Alexander Duyck 92418fb147 i40e/i40evf: Use usec value instead of reg value for ITR defines
Instead of using the register value for the defines when setting up the
ring ITR we can just use the actual values and avoid the use of shifts and
macros to translate between the values we have and the values we want.

This helps to make the code more readable as we can quickly translate from
one value to the other.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2018-02-12 11:29:47 -08:00
Alexander Duyck 4ff17929e6 i40e/i40evf: Don't bother setting the CLEARPBA bit
The CLEARPBA bit in the dynamic interrupt control register actually has
no effect either way on the hardware. As per errata 28 in the XL710
specification update the interrupt is actually cleared any time the
register is written with the INTENA_MSK bit set to 0. As such the act of
toggling the enable bit actually will trigger the interrupt being
cleared and could lead to potential lost events if auto-masking is
not enabled.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2018-02-12 10:56:16 -08:00
Alexander Duyck 71dc371993 i40e/i40evf: Clean up logic for adaptive ITR
The logic for dynamic ITR update is confusing at best as there were odd
paths chosen for how to find the rings associated with a given queue based
on the vector index and other inconsistencies throughout the code.

This patch is an attempt to clean up the logic so that we can more easily
understand what is going on. Specifically if there is a Rx or Tx ring that
is enabled in dynamic mode on the q_vector it is allowed to override the
other side of the interrupt moderation. While it isn't correct all this
patch is doing is cleaning up the logic for now so that when we come
through and fix it we can more easily identify that this is wrong.

The other big change made here is that we replace references to:
	vsi->rx_rings[q_vector->v_idx]->itr_setting
with:
	q_vector->rx.ring->itr_setting

The general idea is we can avoid the long pointer chase since just
accessing q_vector->rx.ring is a single pointer access versus having to
chase down vsi->rx_rings, and then finding the pointer in the array, and
finally chasing down the itr_setting from there.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2018-02-12 10:35:49 -08:00
Alexander Duyck 40588ca651 i40e/i40evf: Only track one ITR setting per ring instead of Tx/Rx
The rings are already split out into Tx and Rx rings so it doesn't make
sense to have any single ring store both a Tx and Rx itr_setting value.
Since that is the case drop the pair in favor of storing just a single ITR
value.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2018-02-12 10:27:12 -08:00
Alan Brady 11a350c965 i40e: fix typo in function description
'bufer' should be 'buffer'

Signed-off-by: Alan Brady <alan.brady@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2018-02-12 09:55:34 -08:00
Alexander Duyck a3f9fb5ef3 i40e/i40evf: Record ITR register location in the q_vector
The drivers for i40e and i40evf had a reg_idx value stored in the q_vector
that was going completely unused. I can only assume this was copied over
from ixgbe and nobody knew how to use it.

I'm going to make use of the value to avoid having to compute the vector
and thus the register index for multiple paths throughout the drivers.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2018-01-26 13:23:46 -08:00
Sudheer Mogilappagari 07d44190a3 i40e/i40evf: Detect and recover hung queue scenario
In VFs, there is a known issue which can cause writebacks
to not occur when interrupts are disabled and there are
less than 4 descriptors resulting in TX timeout. Timeout
can also occur due to lost interrupt.

The current implementation for detecting and recovering
from hung queues in the PF is problematic because it actually
actively encourages lost interrupts.  By triggering a SW
interrupt, interrupts are forced on.  If we are already in
napi_poll and an interrupt fires, napi_poll will not be
rescheduled and the interrupt is effectively lost; thereby
potentially *causing* hung queues.

This patch checks whether packets are being processed between
every watchdog cycle and determine potential hung queue and
fires triggers SW interrupt only for that particular queue.

Signed-off-by: Sudheer Mogilappagari <sudheer.mogilappagari@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2018-01-23 11:29:19 -08:00
David S. Miller a0ce093180 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-01-09 10:37:00 -05:00
Jesper Dangaard Brouer 871288248d i40e: setup xdp_rxq_info
The i40e driver has a special "FDIR" RX-ring (I40E_VSI_FDIR) which is
a sideband channel for configuring/updating the flow director tables.
This (i40e_vsi_)type does not invoke XDP-ebpf code.

As suggested by Björn (V2): Instead of marking this I40E_VSI_FDIR RX-ring
a special case, reverse the logic and only select RX-rings of type
I40E_VSI_MAIN to register xdp_rxq_info's for.

Driver hook points for xdp_rxq_info:
 * reg  : i40e_setup_rx_descriptors (via i40e_vsi_setup_rx_resources)
 * unreg: i40e_free_rx_resources    (via i40e_vsi_free_rx_resources)

Tested on actual hardware with samples/bpf program.

V2: Fixed bug in i40e_set_ringparam (memset zero) + match on I40E_VSI_MAIN.
V4: Update patch desc that got out-of-sync with code.

Cc: intel-wired-lan@lists.osuosl.org
Cc: Björn Töpel <bjorn.topel@intel.com>
Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Cc: Paul Menzel <pmenzel@molgen.mpg.de>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Reviewed-by: Paul Menzel <pmenzel@molgen.mpg.de>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-01-05 15:21:21 -08:00
Alexander Duyck 248de22e63 i40e/i40evf: Account for frags split over multiple descriptors in check linearize
The original code for __i40e_chk_linearize didn't take into account the
fact that if a fragment is 16K in size or larger it has to be split over 2
descriptors and the smaller of those 2 descriptors will be on the trailing
edge of the transmit. As a result we can get into situations where we didn't
catch requests that could result in a Tx hang.

This patch takes care of that by subtracting the length of all but the
trailing edge of the stale fragment before we test for sum. By doing this
we can guarantee that we have all cases covered, including the case of a
fragment that spans multiple descriptors. We don't need to worry about
checking the inner portions of this since 12K is the maximum aligned DMA
size and that is larger than any MSS will ever be since the MTU limit for
jumbos is something on the order of 9K.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2018-01-03 08:47:29 -08:00
Brian King 52c6912fde i40e: Use smp_rmb rather than read_barrier_depends
The original issue being fixed in this patch was seen with the ixgbe
driver, but the same issue exists with i40e as well, as the code is
very similar. read_barrier_depends is not sufficient to ensure
loads following it are not speculatively loaded out of order
by the CPU, which can result in stale data being loaded, causing
potential system crashes.

Cc: stable <stable@vger.kernel.org>
Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Acked-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2017-11-21 23:43:21 -08:00
Alexander Duyck aa250f1186 i40e/i40evf: Revert "i40e/i40evf: bump tail only in multiples of 8"
This reverts commit 11f29003d6.

I am reverting this as I am fairly certain this can result in a memory leak
when combined with the current page recycling scheme. Specifically we end
up attempting to allocate fewer buffers than we recycled and this results
in us rewinding the next to alloc pointer which leads to leaks when we
overwrite the rx_buffer_info when processing the next frame.

Fixes: 11f29003d6 ("i40e/i40evf: bump tail only in multiples of 8")
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2017-10-31 10:41:10 -07:00
David S. Miller e1ea2f9856 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Several conflicts here.

NFP driver bug fix adding nfp_netdev_is_nfp_repr() check to
nfp_fl_output() needed some adjustments because the code block is in
an else block now.

Parallel additions to net/pkt_cls.h and net/sch_generic.h

A bug fix in __tcp_retransmit_skb() conflicted with some of
the rbtree changes in net-next.

The tc action RCU callback fixes in 'net' had some overlap with some
of the recent tcf_block reworking.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-30 21:09:24 +09:00
Alexander Duyck 62b4c6694d i40e: Add programming descriptors to cleaned_count
This patch updates the i40e driver to include programming descriptors in
the cleaned_count. Without this change it becomes possible for us to leak
memory as we don't trigger a large enough allocation when the time comes to
allocate new buffers and we end up overwriting a number of rx_buffers equal
to the number of programming descriptors we encountered.

Fixes: 0e626ff7cc ("i40e: Fix support for flow director programming status")
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Anders K. Pedersen <akp@cohaesio.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2017-10-26 07:42:58 -07:00
Alexander Duyck 10781348ca i40e: Fix incorrect use of tx_itr_setting when checking for Rx ITR setup
It looks like there was either a copy/paste error or just a typo that
resulted in the Tx ITR setting being used to determine if we were using
adaptive Rx interrupt moderation or not.

This patch fixes the typo.

Fixes: 65e87c0398 ("i40evf: support queue-specific settings for interrupt moderation")
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2017-10-26 07:42:58 -07:00
David S. Miller f8ddadc4db Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
There were quite a few overlapping sets of changes here.

Daniel's bug fix for off-by-ones in the new BPF branch instructions,
along with the added allowances for "data_end > ptr + x" forms
collided with the metadata additions.

Along with those three changes came veritifer test cases, which in
their final form I tried to group together properly.  If I had just
trimmed GIT's conflict tags as-is, this would have split up the
meta tests unnecessarily.

In the socketmap code, a set of preemption disabling changes
overlapped with the rename of bpf_compute_data_end() to
bpf_compute_data_pointers().

Changes were made to the mv88e6060.c driver set addr method
which got removed in net-next.

The hyperv transport socket layer had a locking change in 'net'
which overlapped with a change of socket state macro usage
in 'net-next'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-22 13:39:14 +01:00
Alexander Duyck 2b9478ffc5 i40e: Fix memory leak related filter programming status
It looks like we weren't correctly placing the pages from buffers that had
been used to return a filter programming status back on the ring. As a
result they were being overwritten and tracking of the pages was lost.

This change works to correct that by incorporating part of
i40e_put_rx_buffer into the programming status handler code. As a result we
should now be correctly placing the pages for those buffers on the
re-allocation list instead of letting them stay in place.

Fixes: 0e626ff7cc ("i40e: Fix support for flow director programming status")
Reported-by: Anders K. Pedersen <akp@cohaesio.com>
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Anders K Pedersen <akp@cohaesio.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2017-10-10 08:04:36 -07:00
Jacob Keller 11f29003d6 i40e/i40evf: bump tail only in multiples of 8
Hardware only fetches descriptors on cachelines of 8, essentially
ignoring the lower 3 bits of the tail register. Thus, it is pointless to
bump tail by an unaligned access as the hardware will ignore some of the
new descriptors we allocated. Thus, it's ideal if we can ensure tail
writes are always aligned to 8.

At first, it seems like we'd already do this, since we allocate
descriptors in batches which are a multiple of 8. Since we'd always
increment by a multiple of 8, it seems like the value should always be
aligned.

However, this ignores allocation failures. If we fail to allocate
a buffer, our tail register will become unaligned. Once it has become
unaligned it will essentially be stuck unaligned until a buffer
allocation happens to fail at the exact amount necessary to re-align it.

We can do better, by simply rounding down the number of buffers we're
about to allocate (cleaned_count) such that "next_to_clean
+ cleaned_count" is rounded to the nearest multiple of 8.

We do this by calculating how far off that value is and subtracting it
from the cleaned_count. This essentially defers allocation of buffers if
they're going to be ignored by hardware anyways, and re-aligns our
next_to_use and tail values after a failure to allocate a descriptor.

This calculation ensures that we always align the tail writes in a way
the hardware expects and don't unnecessarily allocate buffers which
won't be fetched immediately.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2017-10-09 14:26:29 -07:00
Jacob Keller dbadbbe235 i40e/i40evf: always set the CLEARPBA flag when re-enabling interrupts
In the past we changed driver behavior to not clear the PBA when
re-enabling interrupts. This change was motivated by the flawed belief
that clearing the PBA would cause a lost interrupt if a receive
interrupt occurred while interrupts were disabled.

According to empirical testing this isn't the case. Additionally, the
data sheet specifically says that we should set the CLEARPBA bit when
re-enabling interrupts in a polling setup.

This reverts commit 40d72a5098 ("i40e/i40evf: don't lose interrupts")

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2017-10-09 14:21:26 -07:00
Jacob Keller a5340d933e i40e: ignore skb->xmit_more when deciding to set RS bit
Since commit 6a7fded776 ("i40e: Fix RS bit update in Tx path and
disable force WB workaround") we've tried to "optimize" setting the
RS bit based around skb->xmit_more. This same logic was refactored
in commit 1dc8b53879 ("i40e: Reorder logic for coalescing RS bits"),
but ultimately was not functionally changed.

Using skb->xmit_more in this way is incorrect, because in certain
circumstances we may see a large number of skbs in sequence with
xmit_more set. This leads to a performance loss as the hardware does not
writeback anything for those packets, which delays the time it takes for
us to respond to the stack transmit requests. This significantly impacts
UDP performance, especially when layered with multiple devices, such as
bonding, VLANs, and vnet setups.

This was not noticed until now because it is difficult to create a setup
which reproduces the issue. It was discovered in a UDP_STREAM test in
a VM, connected using a vnet device to a bridge, which is connected to
a bonded pair of X710 ports in active-backup mode with a VLAN. These
layered devices seem to compound the number of skbs transmitted at once
by the qdisc. Additionally, the problem can be masked by reducing the
ITR value.

Since the original commit does not provide strong justification for this
RS bit "optimization", revert to the previous behavior of setting the RS
bit every 4th packet.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2017-10-06 08:11:32 -07:00
Jacob Keller 2b634bb068 i40e/i40evf: rename bytes_per_int to bytes_per_usec
This value is not calculating bytes_per_int, which would actually just
be bytes/ITR_COUNTDOWN_START, but rather it's calculating bytes/usecs.

Rename the variable for clarity so that future developers understand
what the value is actually calculating.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2017-09-29 12:50:58 -07:00
Daniel Borkmann de8f3a83b0 bpf: add meta pointer for direct access
This work enables generic transfer of metadata from XDP into skb. The
basic idea is that we can make use of the fact that the resulting skb
must be linear and already comes with a larger headroom for supporting
bpf_xdp_adjust_head(), which mangles xdp->data. Here, we base our work
on a similar principle and introduce a small helper bpf_xdp_adjust_meta()
for adjusting a new pointer called xdp->data_meta. Thus, the packet has
a flexible and programmable room for meta data, followed by the actual
packet data. struct xdp_buff is therefore laid out that we first point
to data_hard_start, then data_meta directly prepended to data followed
by data_end marking the end of packet. bpf_xdp_adjust_head() takes into
account whether we have meta data already prepended and if so, memmove()s
this along with the given offset provided there's enough room.

xdp->data_meta is optional and programs are not required to use it. The
rationale is that when we process the packet in XDP (e.g. as DoS filter),
we can push further meta data along with it for the XDP_PASS case, and
give the guarantee that a clsact ingress BPF program on the same device
can pick this up for further post-processing. Since we work with skb
there, we can also set skb->mark, skb->priority or other skb meta data
out of BPF, thus having this scratch space generic and programmable
allows for more flexibility than defining a direct 1:1 transfer of
potentially new XDP members into skb (it's also more efficient as we
don't need to initialize/handle each of such new members). The facility
also works together with GRO aggregation. The scratch space at the head
of the packet can be multiple of 4 byte up to 32 byte large. Drivers not
yet supporting xdp->data_meta can simply be set up with xdp->data_meta
as xdp->data + 1 as bpf_xdp_adjust_meta() will detect this and bail out,
such that the subsequent match against xdp->data for later access is
guaranteed to fail.

The verifier treats xdp->data_meta/xdp->data the same way as we treat
xdp->data/xdp->data_end pointer comparisons. The requirement for doing
the compare against xdp->data is that it hasn't been modified from it's
original address we got from ctx access. It may have a range marking
already from prior successful xdp->data/xdp->data_end pointer comparisons
though.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-26 13:36:44 -07:00