Commit Graph

455 Commits

Author SHA1 Message Date
Toshiaki Makita
d7dfc5cf56 virtio_net: Add ethtool stats
The main purpose of this patch is adding a way of checking per-queue stats.
It's useful to debug performance problems on multiqueue environment.

$ ethtool -S ens10
NIC statistics:
     rx_queue_0_packets: 2090408
     rx_queue_0_bytes: 3164825094
     rx_queue_1_packets: 2082531
     rx_queue_1_bytes: 3152932314
     tx_queue_0_packets: 2770841
     tx_queue_0_bytes: 4194955474
     tx_queue_1_packets: 3084697
     tx_queue_1_bytes: 4670196372

This change converts existing per-cpu stats structure into per-queue one.
This should not impact on performance since each queue counter is not
updated concurrently by multiple cpus.

Performance numbers:
 - Guest has 2 vcpus and 2 queues
 - Guest runs netserver
 - Host runs 100-flow super_netperf

                     Before      After       Diff
UDP_STREAM 18byte        86.22       87.00   +0.90%
UDP_STREAM 1472byte    4055.27     4042.18   -0.32%
TCP_STREAM            16956.32    16890.63   -0.39%
UDP_RR               178667.11   185862.70   +4.03%
TCP_RR               128473.04   124985.81   -2.71%

Signed-off-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-22 15:25:37 -05:00
Jason Baron
faa9b39f0e virtio_net: propagate linkspeed/duplex settings from the hypervisor
The ability to set speed and duplex for virtio_net is useful in various
scenarios as described here:

16032be virtio_net: add ethtool support for set and get of settings

However, it would be nice to be able to set this from the hypervisor,
such that virtio_net doesn't require custom guest ethtool commands.

Introduce a new feature flag, VIRTIO_NET_F_SPEED_DUPLEX, which allows
the hypervisor to export a linkspeed and duplex setting. The user can
subsequently overwrite it later if desired via: 'ethtool -s'.

Note that VIRTIO_NET_F_SPEED_DUPLEX is defined as bit 63, the intention
is that device feature bits are to grow down from bit 63, since the
transports are starting from bit 24 and growing up.

Signed-off-by: Jason Baron <jbaron@akamai.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: virtio-dev@lists.oasis-open.org
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-09 11:37:56 -05:00
Jesper Dangaard Brouer
754b8a21a9 virtio_net: setup xdp_rxq_info
The virtio_net driver doesn't dynamically change the RX-ring queue
layout and backing pages, but instead reject XDP setup if all the
conditions for XDP is not meet.  Thus, the xdp_rxq_info also remains
fairly static.  This allow us to simply add the reg/unreg to
net_device open/close functions.

Driver hook points for xdp_rxq_info:
 * reg  : virtnet_open
 * unreg: virtnet_close

V3:
 - bugfix, also setup xdp.rxq in receive_mergeable()
 - Tested bpf-sample prog inside guest on a virtio_net device

Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: virtualization@lists.linux-foundation.org
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Reviewed-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-01-05 15:21:22 -08:00
David S. Miller
51e18a453f Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflict was two parallel additions of include files to sch_generic.c,
no biggie.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-09 22:09:55 -05:00
Linus Torvalds
900add27f5 virtio: bugfixes
A couple of minor bugfixes.
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio bugfixes from Michael Tsirkin:
 "A couple of minor bugfixes"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  virtio_net: fix return value check in receive_mergeable()
  virtio_mmio: add cleanup for virtio_mmio_remove
  virtio_mmio: add cleanup for virtio_mmio_probe
2017-12-08 12:58:51 -08:00
Toshiaki Makita
fdaa767aef virtio_net: Disable interrupts if napi_complete_done rescheduled napi
Since commit 39e6c8208d ("net: solve a NAPI race") napi has been able
to be rescheduled within napi_complete_done() even in non-busypoll case,
but virtnet_poll() always enabled interrupts before complete, and when
napi was rescheduled within napi_complete_done() it did not disable
interrupts.
This caused more interrupts when event idx is disabled.

According to commit cbdadbbf0c ("virtio_net: fix race in RX VQ
processing") we cannot place virtqueue_enable_cb_prepare() after
NAPI_STATE_SCHED is cleared, so disable interrupts again if
napi_complete_done() returned false.

Tested with vhost-user of OVS 2.7 on host, which does not have the event
idx feature.

* Before patch:

$ netperf -t UDP_STREAM -H 192.168.150.253 -l 60 -- -m 1472
MIGRATED UDP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 192.168.150.253 () port 0 AF_INET
Socket  Message  Elapsed      Messages
Size    Size     Time         Okay Errors   Throughput
bytes   bytes    secs            #      #   10^6bits/sec

212992    1472   60.00     32763206      0    6430.32
212992           60.00     23384299           4589.56

Interrupts on guest: 9872369
Packets/interrupt:   2.37

* After patch

$ netperf -t UDP_STREAM -H 192.168.150.253 -l 60 -- -m 1472
MIGRATED UDP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 192.168.150.253 () port 0 AF_INET
Socket  Message  Elapsed      Messages
Size    Size     Time         Okay Errors   Throughput
bytes   bytes    secs            #      #   10^6bits/sec

212992    1472   60.00     32794646      0    6436.49
212992           60.00     32793501           6436.27

Interrupts on guest: 4941299
Packets/interrupt:   6.64

Signed-off-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-08 13:18:40 -05:00
Yunjian Wang
03e9f8a05b virtio_net: fix return value check in receive_mergeable()
The function virtqueue_get_buf_ctx() could return NULL, the return
value 'buf' need to be checked with NULL, not value 'ctx'.

Signed-off-by: Yunjian Wang <wangyunjian@huawei.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-12-07 18:34:52 +02:00
Linus Torvalds
7c225c69f8 Merge branch 'akpm' (patches from Andrew)
Merge updates from Andrew Morton:

 - a few misc bits

 - ocfs2 updates

 - almost all of MM

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (131 commits)
  memory hotplug: fix comments when adding section
  mm: make alloc_node_mem_map a void call if we don't have CONFIG_FLAT_NODE_MEM_MAP
  mm: simplify nodemask printing
  mm,oom_reaper: remove pointless kthread_run() error check
  mm/page_ext.c: check if page_ext is not prepared
  writeback: remove unused function parameter
  mm: do not rely on preempt_count in print_vma_addr
  mm, sparse: do not swamp log with huge vmemmap allocation failures
  mm/hmm: remove redundant variable align_end
  mm/list_lru.c: mark expected switch fall-through
  mm/shmem.c: mark expected switch fall-through
  mm/page_alloc.c: broken deferred calculation
  mm: don't warn about allocations which stall for too long
  fs: fuse: account fuse_inode slab memory as reclaimable
  mm, page_alloc: fix potential false positive in __zone_watermark_ok
  mm: mlock: remove lru_add_drain_all()
  mm, sysctl: make NUMA stats configurable
  shmem: convert shmem_init_inodecache() to void
  Unify migrate_pages and move_pages access checks
  mm, pagevec: rename pagevec drained field
  ...
2017-11-15 19:42:40 -08:00
Mel Gorman
453f85d43f mm: remove __GFP_COLD
As the page free path makes no distinction between cache hot and cold
pages, there is no real useful ordering of pages in the free list that
allocation requests can take advantage of.  Juding from the users of
__GFP_COLD, it is likely that a number of them are the result of copying
other sites instead of actually measuring the impact.  Remove the
__GFP_COLD parameter which simplifies a number of paths in the page
allocator.

This is potentially controversial but bear in mind that the size of the
per-cpu pagelists versus modern cache sizes means that the whole per-cpu
list can often fit in the L3 cache.  Hence, there is only a potential
benefit for microbenchmarks that alloc/free pages in a tight loop.  It's
even worse when THP is taken into account which has little or no chance
of getting a cache-hot page as the per-cpu list is bypassed and the
zeroing of multiple pages will thrash the cache anyway.

The truncate microbenchmarks are not shown as this patch affects the
allocation path and not the free path.  A page fault microbenchmark was
tested but it showed no sigificant difference which is not surprising
given that the __GFP_COLD branches are a miniscule percentage of the
fault path.

Link: http://lkml.kernel.org/r/20171018075952.10627-9-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15 18:21:06 -08:00
Jakub Kicinski
f4e63525ee net: bpf: rename ndo_xdp to ndo_bpf
ndo_xdp is a control path callback for setting up XDP in the
driver.  We can reuse it for other forms of communication
between the eBPF stack and the drivers.  Rename the callback
and associated structures and definitions.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-05 22:26:18 +09:00
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
Jason Wang
dd54379749 virtio-net: correctly set xdp_xmit for mergeable buffer
We should set xdp_xmit only when xdp_do_redirect() succeed.

Cc: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-22 18:15:33 -07:00
Jason Wang
186b3c998c virtio-net: support XDP_REDIRECT
This patch tries to add XDP_REDIRECT for virtio-net. The changes are
not complex as we could use exist XDP_TX helpers for most of the
work. The rest is passing the XDP_TX to NAPI handler for implementing
batching.

Cc: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-20 14:27:52 -07:00
Jason Wang
3124034535 virtio-net: add packet len average only when needed during XDP
There's no need to add packet len average in the case of XDP_PASS
since it will be done soon after skb is created.

Cc: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-20 14:27:52 -07:00
Jason Wang
9457642a40 virtio-net: remove unnecessary parameter of virtnet_xdp_xmit()
CC: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-20 14:27:52 -07:00
David S. Miller
6026e043d0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Three cases of simple overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-01 17:42:05 -07:00
Eric Dumazet
dadc0736f7 virtio_net: be drop monitor friendly
This change is needed to not fool drop monitor.
(perf record ... -e skb:kfree_skb )

Packets were properly sent and are consumed after TX completion.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-24 11:50:21 -07:00
stephen hemminger
718ad681ef net: drop unused attribute argument from sysfs queue funcs
The show and store functions don't need/use the attribute.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-18 22:38:31 -07:00
stephen hemminger
a4a765031d virtio: put paren around sizeof
Kernel coding style is to put paren around operand of sizeof.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-16 11:01:57 -07:00
Colin Ian King
7acd432968 virtio-net: make array guest_offloads static
The array guest_offloads is local to the source and does not need to
be in global scope, so make it static. Also tweak formatting.

Cleans up sparse warnings:
symbol 'guest_offloads' was not declared. Should it be static?

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-13 20:09:49 -07:00
David S. Miller
29fda25a2d Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Two minor conflicts in virtio_net driver (bug fix overlapping addition
of a helper) and MAINTAINERS (new driver edit overlapping revamp of
PHY entry).

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-01 10:07:50 -07:00
Linus Torvalds
bc78d646e7 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Handle notifier registry failures properly in tun/tap driver, from
    Tonghao Zhang.

 2) Fix bpf verifier handling of subtraction bounds and add a testcase
    for this, from Edward Cree.

 3) Increase reset timeout in ftgmac100 driver, from Ben Herrenschmidt.

 4) Fix use after free in prd_retire_rx_blk_timer_exired() in AF_PACKET,
    from Cong Wang.

 5) Fix SElinux regression due to recent UDP optimizations, from Paolo
    Abeni.

 6) We accidently increment IPSTATS_MIB_FRAGFAILS in the ipv6 code
    paths, fix from Stefano Brivio.

 7) Fix some mem leaks in dccp, from Xin Long.

 8) Adjust MDIO_BUS kconfig deps to avoid build errors, from Arnd
    Bergmann.

 9) Mac address length check and buffer size fixes from Cong Wang.

10) Don't leak sockets in ipv6 udp early demux, from Paolo Abeni.

11) Fix return value when copy_from_user() fails in
    bpf_prog_get_info_by_fd(), from Daniel Borkmann.

12) Handle PHY_HALTED properly in phy library state machine, from
    Florian Fainelli.

13) Fix OOPS in fib_sync_down_dev(), from Ido Schimmel.

14) Fix truesize calculation in virtio_net which led to performance
    regressions, from Michael S Tsirkin.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (76 commits)
  samples/bpf: fix bpf tunnel cleanup
  udp6: fix jumbogram reception
  ppp: Fix a scheduling-while-atomic bug in del_chan
  Revert "net: bcmgenet: Remove init parameter from bcmgenet_mii_config"
  virtio_net: fix truesize for mergeable buffers
  mv643xx_eth: fix of_irq_to_resource() error check
  MAINTAINERS: Add more files to the PHY LIBRARY section
  ipv4: fib: Fix NULL pointer deref during fib_sync_down_dev()
  net: phy: Correctly process PHY_HALTED in phy_stop_machine()
  sunhme: fix up GREG_STAT and GREG_IMASK register offsets
  bpf: fix bpf_prog_get_info_by_fd to dump correct xlated_prog_len
  tcp: avoid bogus gcc-7 array-bounds warning
  net: tc35815: fix spelling mistake: "Intterrupt" -> "Interrupt"
  bpf: don't indicate success when copy_from_user fails
  udp6: fix socket leak on early demux
  net: thunderx: Fix BGX transmit stall due to underflow
  Revert "vhost: cache used event for better performance"
  team: use a larger struct for mac address
  net: check dev->addr_len for dev_set_mac_address()
  phy: bcm-ns-usb3: fix MDIO_BUS dependency
  ...
2017-07-31 22:36:42 -07:00
Michael S. Tsirkin
1daa8790d0 virtio_net: fix truesize for mergeable buffers
Seth Forshee noticed a performance degradation with some workloads.
This turns out to be due to packet drops.  Euan Kemp noticed that this
is because we drop all packets where length exceeds the truesize, but
for some packets we add in extra memory without updating the truesize.
This in turn was kept around unchanged from ab7db91705 ("virtio-net:
auto-tune mergeable rx buffer size for improved performance").  That
commit had an internal reason not to account for the extra space: not
enough bits to do it.  No longer true so let's account for the allocated
length exactly.

Many thanks to Seth Forshee for the report and bisecting and Euan Kemp
for debugging the issue.

Fixes: 680557cf79 ("virtio_net: rework mergeable buffer handling")
Reported-by: Euan Kemp <euan.kemp@coreos.com>
Tested-by: Euan Kemp <euan.kemp@coreos.com>
Reported-by: Seth Forshee <seth.forshee@canonical.com>
Tested-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-31 18:02:46 -07:00
Arnd Bergmann
67a75194bc virtio-net: mark PM functions as __maybe_unused
After removing the reset function, the freeze and restore functions
are now unused when CONFIG_PM_SLEEP is disabled:

drivers/net/virtio_net.c:1881:12: error: 'virtnet_restore_up' defined but not used [-Werror=unused-function]
 static int virtnet_restore_up(struct virtio_device *vdev)
drivers/net/virtio_net.c:1859:13: error: 'virtnet_freeze_down' defined but not used [-Werror=unused-function]
 static void virtnet_freeze_down(struct virtio_device *vdev)

A more robust way to do this is to remove the #ifdef around the callers
and instead mark them as __maybe_unused. The compiler will now just
silently drop the unused code.

Fixes: 4941d472bf ("virtio-net: do not reset during XDP set")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-25 21:22:45 -07:00
Andrew Jones
cfa0ebc9d6 virtio-net: fix module unloading
Unregister the driver before removing multi-instance hotplug
callbacks. This order avoids the warning issued from
__cpuhp_remove_state_cpuslocked when the number of remaining
instances isn't yet zero.

Fixes: 8017c27919 ("net/virtio-net: Convert to hotplug state machine")
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-07-25 16:37:36 +03:00
Jason Wang
3f93522ffa virtio-net: switch off offloads on demand if possible on XDP set
Current XDP implementation wants guest offloads feature to be disabled
on device. This is inconvenient and means guest can't benefit from
offloads if XDP is not used. This patch tries to address this
limitation by disabling the offloads on demand through control guest
offloads. Guest offloads will be disabled and enabled on demand on XDP
set.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-24 13:37:00 -07:00
Jason Wang
4941d472bf virtio-net: do not reset during XDP set
We currently reset the device during XDP set, the main reason is
that we allocate more headroom with XDP (for header adjustment).

This works but causes network downtime for users.

Previous patches encoded the headroom in the buffer context,
this makes it possible to detect the case where a buffer
with headroom insufficient for XDP is added to the queue and
XDP is enabled afterwards.

Upon detection, we handle this case by copying the packet
(slow, but it's a temporary condition).

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-24 13:37:00 -07:00
Jason Wang
192f68cf35 virtio-net: switch to use new ctx API for small buffer
Use ctx API to store headroom for small buffers.
Following patches will retrieve this info and use it for XDP.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-24 13:37:00 -07:00
Jason Wang
28b39bc7c5 virtio-net: pack headroom into ctx for mergeable buffers
Pack headroom into ctx - this way when we get a buffer we can figure out
the actual headroom that was allocated for the buffer. Will be helpful
to optimize switching between XDP and non-XDP modes which have different
headroom requirements.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-24 13:37:00 -07:00
David S. Miller
e078de0378 virtio_net: Remove references to NETIF_F_UFO.
It is going away.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-17 09:52:58 -07:00
Jason Wang
55281621b6 virtio-net: fix leaking of ctx array
Fixes: commit d45b897b11 ("virtio_net: allow specifying context for rx")
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-07 20:03:41 +01:00
David S. Miller
b079115937 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
A set of overlapping changes in macvlan and the rocker
driver, nothing serious.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-30 12:43:08 -04:00
Jason Wang
713a98d90c virtio-net: serialize tx routine during reset
We don't hold any tx lock when trying to disable TX during reset, this
would lead a use after free since ndo_start_xmit() tries to access
the virtqueue which has already been freed. Fix this by using
netif_tx_disable() before freeing the vqs, this could make sure no tx
after vq freeing.

Reported-by: Jean-Philippe Menil <jpmenil@gmail.com>
Tested-by: Jean-Philippe Menil <jpmenil@gmail.com>
Fixes commit f600b69050 ("virtio_net: Add XDP support")
Cc: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Robert McCabe <robert.mccabe@rockwellcollins.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-29 12:51:59 -04:00
Martin KaFai Lau
5b0e6629be bpf: virtio_net: Report bpf_prog ID during XDP_QUERY_PROG
Add support to virtio_net to report bpf_prog ID during XDP_QUERY_PROG.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Jason Wang <jasowang@redhat.com>
Acked-by: Alexei Starovoitov <ast@fb.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-16 11:58:36 -04:00
Johannes Berg
59ae1d127a networking: introduce and use skb_put_data()
A common pattern with skb_put() is to just want to memcpy()
some data into the new space, introduce skb_put_data() for
this.

An spatch similar to the one for skb_put_zero() converts many
of the places using it:

    @@
    identifier p, p2;
    expression len, skb, data;
    type t, t2;
    @@
    (
    -p = skb_put(skb, len);
    +p = skb_put_data(skb, data, len);
    |
    -p = (t)skb_put(skb, len);
    +p = skb_put_data(skb, data, len);
    )
    (
    p2 = (t2)p;
    -memcpy(p2, data, len);
    |
    -memcpy(p, data, len);
    )

    @@
    type t, t2;
    identifier p, p2;
    expression skb, data;
    @@
    t *p;
    ...
    (
    -p = skb_put(skb, sizeof(t));
    +p = skb_put_data(skb, data, sizeof(t));
    |
    -p = (t *)skb_put(skb, sizeof(t));
    +p = skb_put_data(skb, data, sizeof(t));
    )
    (
    p2 = (t2)p;
    -memcpy(p2, data, sizeof(*p));
    |
    -memcpy(p, data, sizeof(*p));
    )

    @@
    expression skb, len, data;
    @@
    -memcpy(skb_put(skb, len), data, len);
    +skb_put_data(skb, data, len);

(again, manually post-processed to retain some comments)

Reviewed-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-16 11:48:37 -04:00
David S. Miller
216fe8f021 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Just some simple overlapping changes in marvell PHY driver
and the DSA core code.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-06 22:20:08 -04:00
Jason A. Donenfeld
e2fcad58fd virtio_net: check return value of skb_to_sgvec always
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-04 23:01:48 -04:00
Michael S. Tsirkin
f0c3192cee virtio_net: lower limit on buffer size
commit d85b758f72 ("virtio_net: fix support for small rings")
was supposed to increase the buffer size for small rings but had an
unintentional side effect of decreasing it for large rings. This seems
to break some setups - it's not yet clear why, but increasing buffer
size back to what it was before helps.

Fixes: d85b758f72 ("virtio_net: fix support for small rings")
Reported-by: Mikulas Patocka <mpatocka@redhat.com>
Reported-by: "J. Bruce Fields" <bfields@fieldses.org>
Tested-by: Mikulas Patocka <mpatocka@redhat.com>
Tested-by: "J. Bruce Fields" <bfields@fieldses.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-02 14:32:34 -04:00
Vlad Yasevich
2836b4f224 virtio-net: enable TSO/checksum offloads for Q-in-Q vlans
Since virtio does not provide it's own ndo_features_check handler,
TSO, and now checksum offload, are disabled for stacked vlans.
Re-enable the support and let the host take care of it.  This
restores/improves Guest-to-Guest performance over Q-in-Q vlans.

Acked-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Vladislav Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-24 16:27:14 -04:00
Linus Torvalds
c44b594303 virtio: fixes, cleanups, performance
A bunch of changes to virtio, most affecting virtio net.
 ptr_ring batched zeroing - first of batching enhancements
 that seems ready.
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio updates from Michael Tsirkin:
 "Fixes, cleanups, performance

  A bunch of changes to virtio, most affecting virtio net. Also ptr_ring
  batched zeroing - first of batching enhancements that seems ready."

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  s390/virtio: change maintainership
  tools/virtio: fix spelling mistake: "wakeus" -> "wakeups"
  virtio_net: tidy a couple debug statements
  ptr_ring: support testing different batching sizes
  ringtest: support test specific parameters
  ptr_ring: batch ring zeroing
  virtio: virtio_driver doc
  virtio_net: don't reset twice on XDP on/off
  virtio_net: fix support for small rings
  virtio_net: reduce alignment for buffers
  virtio_net: rework mergeable buffer handling
  virtio_net: allow specifying context for rx
  virtio: allow extra context per descriptor
  tools/virtio: fix build breakage
  virtio: add context flag to find vqs
  virtio: wrap find_vqs
  ringtest: fix an assert statement
2017-05-10 11:33:08 -07:00
Dan Carpenter
56da5fd04e virtio_net: tidy a couple debug statements
We are printing a decimal value for truesize so we shouldn't use an "0x"
prefix.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-05-09 16:43:24 +03:00
Michael S. Tsirkin
5f24df0945 virtio_net: don't reset twice on XDP on/off
We already do a reset once in remove_vq_common -
there appears to be no point in doing another one
when we add/remove XDP.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-05-09 16:43:22 +03:00
Michael S. Tsirkin
d85b758f72 virtio_net: fix support for small rings
When ring size is small (<32 entries) making buffers smaller means a
full ring might not be able to hold enough buffers to fit a single large
packet.

Make sure a ring full of buffers is large enough to allow at least one
packet of max size.

Fixes: 2613af0ed1 ("virtio_net: migrate mergeable rx buffers to page frag allocators")
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-05-09 16:43:21 +03:00
Michael S. Tsirkin
e377fcc848 virtio_net: reduce alignment for buffers
We don't need to align length to any particular
value anymore. Aligning to L1 cache size probably
sill makes sense to reduce false sharing.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-05-09 16:43:21 +03:00
Michael S. Tsirkin
680557cf79 virtio_net: rework mergeable buffer handling
Use the new _ctx virtio API to maintain true length for each buffer.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-05-09 16:43:20 +03:00
Michael S. Tsirkin
d45b897b11 virtio_net: allow specifying context for rx
With mergeable buffers we never use s/g for rx,
so allow specifying context in that case.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-05-09 16:43:15 +03:00
Daniel Borkmann
4d463c4dbc xdp: use common helper for netlink extended ack reporting
Small follow-up to d74a32acd5 ("xdp: use netlink extended ACK reporting")
in order to let drivers all use the same NL_SET_ERR_MSG_MOD() helper macro
for reporting. This also ensures that we consistently add the driver's
prefix for dumping the report in user space to indicate that the error
message is driver specific and not coming from core code. Furthermore,
NL_SET_ERR_MSG_MOD() now reuses NL_SET_ERR_MSG() and thus makes all macros
check the pointer as suggested.

References: https://www.spinics.net/lists/netdev/msg433267.html
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-03 09:51:24 -04:00
Michael S. Tsirkin
9b2bbdb227 virtio: wrap find_vqs
We are going to add more parameters to find_vqs, let's wrap the call so
we don't need to tweak all drivers every time.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-05-02 23:41:42 +03:00
Jakub Kicinski
9861ce039c virtio_net: make use of extended ack message reporting
Try to carry error messages to the user via the netlink extended
ack message attribute.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-01 10:35:48 -04:00
Willem de Bruijn
1d11e732e7 virtio-net: use netif_tx_napi_add for tx napi
Avoid hashing the tx napi struct into napi_hash[], which is used for
busy polling receive queues.

Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-30 22:33:04 -04:00
Willem de Bruijn
78a57b482a virtio-net: on tx, only call napi_disable if tx napi is on
As of tx napi, device down (`ip link set dev $dev down`) hangs unless
tx napi is enabled. Else napi_enable is not called, so napi_disable
will spin on test_and_set_bit NAPI_STATE_SCHED.

Only call napi_disable if tx napi is enabled.

Fixes: 5a719c2552ca ("virtio-net: transmit napi")
Reported-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-26 14:50:06 -04:00
Willem de Bruijn
bdb12e0d2f virtio-net: keep tx interrupts disabled unless kick
Tx napi mode increases the rate of transmit interrupts. Suppress some
by masking interrupts while more packets are expected. The interrupts
will be reenabled before the last packet is sent.

This optimization reduces the througput drop with tx napi for
unidirectional flows such as UDP_STREAM that do not benefit from
cleaning tx completions in the the receive napi handler.

Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-24 23:55:19 -04:00
Willem de Bruijn
7b0411ef4a virtio-net: clean tx descriptors from rx napi
Amortize the cost of virtual interrupts by doing both rx and tx work
on reception of a receive interrupt if tx napi is enabled. With
VIRTIO_F_EVENT_IDX, this suppresses most explicit tx completion
interrupts for bidirectional workloads.

Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-24 23:55:19 -04:00
Willem de Bruijn
ea7735d97b virtio-net: move free_old_xmit_skbs
An upcoming patch will call free_old_xmit_skbs indirectly from
virtnet_poll. Move the function above this to avoid having to
introduce a forward declaration.

This is a pure move: no code changes.

Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-24 23:55:19 -04:00
Willem de Bruijn
b92f1e6751 virtio-net: transmit napi
Convert virtio-net to a standard napi tx completion path. This enables
better TCP pacing using TCP small queues and increases single stream
throughput.

The virtio-net driver currently cleans tx descriptors on transmission
of new packets in ndo_start_xmit. Latency depends on new traffic, so
is unbounded. To avoid deadlock when a socket reaches its snd limit,
packets are orphaned on tranmission. This breaks socket backpressure,
including TSQ.

Napi increases the number of interrupts generated compared to the
current model, which keeps interrupts disabled as long as the ring
has enough free descriptors. Keep tx napi optional and disabled for
now. Follow-on patches will reduce the interrupt cost.

Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-24 23:55:19 -04:00
Willem de Bruijn
e4e8452a4a virtio-net: napi helper functions
Prepare virtio-net for tx napi by converting existing napi code to
use helper functions. This also deduplicates some logic.

Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-24 23:55:19 -04:00
David S. Miller
6b6cbc1471 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts were simply overlapping changes.  In the net/ipv4/route.c
case the code had simply moved around a little bit and the same fix
was made in both 'net' and 'net-next'.

In the net/sched/sch_generic.c case a fix in 'net' happened at
the same time that a new argument was added to qdisc_hash_add().

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-15 21:16:30 -04:00
Michael S. Tsirkin
fe36cbe067 virtio_net: clear MTU when out of range
virtio attempts to clear the MTU feature bit if the value is out of the
supported range, but this has no real effect since FEATURES_OK has
already been set.

Fix this up by checking the MTU in the new validate callback.

Fixes: 14de9d114a ("virtio-net: Add initial MTU advice feature")
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-04-07 16:38:59 +03:00
Michael S. Tsirkin
2e123b44a3 virtio_net: enable big packets for large MTU values
If one enables e.g. jumbo frames without mergeable
buffers, packets won't fit in 1500 byte buffers
we use. Switch to big packet mode instead.
TODO: make sizing more exact, possibly extend small
packet mode to use larger pages.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-04-07 16:38:59 +03:00
Philippe Reynes
ebb6b4b1ff net: virtio_net: use new api ethtool_{get|set}_link_ksettings
The ethtool api {get|set}_settings is deprecated.
We move this driver to new api {get|set}_link_ksettings.

Signed-off-by: Philippe Reynes <tremyfr@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-22 19:26:52 -07:00
Linus Torvalds
8d70eeb84a Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Fix double-free in batman-adv, from Sven Eckelmann.

 2) Fix packet stats for fast-RX path, from Joannes Berg.

 3) Netfilter's ip_route_me_harder() doesn't handle request sockets
    properly, fix from Florian Westphal.

 4) Fix sendmsg deadlock in rxrpc, from David Howells.

 5) Add missing RCU locking to transport hashtable scan, from Xin Long.

 6) Fix potential packet loss in mlxsw driver, from Ido Schimmel.

 7) Fix race in NAPI handling between poll handlers and busy polling,
    from Eric Dumazet.

 8) TX path in vxlan and geneve need proper RCU locking, from Jakub
    Kicinski.

 9) SYN processing in DCCP and TCP need to disable BH, from Eric
    Dumazet.

10) Properly handle net_enable_timestamp() being invoked from IRQ
    context, also from Eric Dumazet.

11) Fix crash on device-tree systems in xgene driver, from Alban Bedel.

12) Do not call sk_free() on a locked socket, from Arnaldo Carvalho de
    Melo.

13) Fix use-after-free in netvsc driver, from Dexuan Cui.

14) Fix max MTU setting in bonding driver, from WANG Cong.

15) xen-netback hash table can be allocated from softirq context, so use
    GFP_ATOMIC. From Anoob Soman.

16) Fix MAC address change bug in bgmac driver, from Hari Vyas.

17) strparser needs to destroy strp_wq on module exit, from WANG Cong.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (69 commits)
  strparser: destroy workqueue on module exit
  sfc: fix IPID endianness in TSOv2
  sfc: avoid max() in array size
  rds: remove unnecessary returned value check
  rxrpc: Fix potential NULL-pointer exception
  nfp: correct DMA direction in XDP DMA sync
  nfp: don't tell FW about the reserved buffer space
  net: ethernet: bgmac: mac address change bug
  net: ethernet: bgmac: init sequence bug
  xen-netback: don't vfree() queues under spinlock
  xen-netback: keep a local pointer for vif in backend_disconnect()
  netfilter: nf_tables: don't call nfnetlink_set_err() if nfnetlink_send() fails
  netfilter: nft_set_rbtree: incorrect assumption on lower interval lookups
  netfilter: nf_conntrack_sip: fix wrong memory initialisation
  can: flexcan: fix typo in comment
  can: usb_8dev: Fix memory leak of priv->cmd_msg_buffer
  can: gs_usb: fix coding style
  can: gs_usb: Don't use stack memory for USB transfers
  ixgbe: Limit use of 2K buffers on architectures with 256B or larger cache lines
  ixgbe: update the rss key on h/w, when ethtool ask for it
  ...
2017-03-04 17:31:39 -08:00
Linus Torvalds
54d7989f47 virtio, vhost: optimizations, fixes
Looks like a quiet cycle for vhost/virtio, just a couple of minor
 tweaks. Most notable is automatic interrupt affinity for blk and scsi.
 Hopefully other devices are not far behind.
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull vhost updates from Michael Tsirkin:
 "virtio, vhost: optimizations, fixes

  Looks like a quiet cycle for vhost/virtio, just a couple of minor
  tweaks. Most notable is automatic interrupt affinity for blk and scsi.
  Hopefully other devices are not far behind"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  virtio-console: avoid DMA from stack
  vhost: introduce O(1) vq metadata cache
  virtio_scsi: use virtio IRQ affinity
  virtio_blk: use virtio IRQ affinity
  blk-mq: provide a default queue mapping for virtio device
  virtio: provide a method to get the IRQ affinity mask for a virtqueue
  virtio: allow drivers to request IRQ affinity when creating VQs
  virtio_pci: simplify MSI-X setup
  virtio_pci: don't duplicate the msix_enable flag in struct pci_dev
  virtio_pci: use shared interrupts for virtqueues
  virtio_pci: remove struct virtio_pci_vq_info
  vhost: try avoiding avail index access when getting descriptor
  virtio_mmio: expose header to userspace
2017-03-02 13:53:13 -08:00
Johannes Berg
eb1e011a14 average: change to declare precision, not factor
Declaring the factor is counter-intuitive, and people are prone
to using small(-ish) values even when that makes no sense.

Change the DECLARE_EWMA() macro to take the fractional precision,
in bits, rather than a factor, and update all users.

While at it, add some more documentation.

Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2017-03-02 08:32:46 +01:00
Christoph Hellwig
fb5e31d970 virtio: allow drivers to request IRQ affinity when creating VQs
Add a struct irq_affinity pointer to the find_vqs methods, which if set
is used to tell the PCI layer to create the MSI-X vectors for our I/O
virtqueues with the proper affinity from the start.  Compared to after
the fact affinity hints this gives us an instantly working setup and
allows to allocate the irq descritors node-local and avoid interconnect
traffic.  Last but not least this will allow blk-mq queues are created
based on the interrupt affinity for storage drivers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-02-27 20:54:04 +02:00
Jason Wang
f6b10209b9 virtio-net: switch to use build_skb() for small buffer
This patch switch to use build_skb() for small buffer which can have
better performance for both TCP and XDP (since we can work at page
before skb creation). It also remove lots of XDP codes since both
mergeable and small buffer use page frag during refill now.

                       Before   | After
XDP_DROP(xdp1) 64B  :  11.1Mpps | 14.4Mpps

Tested with xdp1/xdp2/xdp_ip_tx_tunnel and netperf.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-21 12:24:52 -05:00
Jason Wang
017b29c38c virito-net: set queues after reset during xdp_set
We set queues before reset which will cause a crash[1]. This is
because is_xdp_raw_buffer_queue() depends on the old xdp queue pairs
number to do the correct detection. So fix this by

- passing xdp queue pairs and current queue pairs to virtnet_reset()
- change vi->xdp_qp after reset but before refill, to make sure both
  free_unused_bufs() and refill can make correct detection of XDP.
- remove the duplicated queue pairs setting before virtnet_reset()
  since we will do it inside virtnet_reset()

[1]

[   74.328168] general protection fault: 0000 [#1] SMP
[   74.328625] Modules linked in: nfsd xfs libcrc32c virtio_net virtio_pci
[   74.329117] CPU: 0 PID: 2849 Comm: xdp2 Not tainted 4.10.0-rc7+ #499
[   74.329577] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.10.1-0-g8891697-prebuilt.qemu-project.org 04/01/2014
[   74.330424] task: ffff88007a894000 task.stack: ffffc90004388000
[   74.330844] RIP: 0010:skb_release_head_state+0x28/0x80
[   74.331298] RSP: 0018:ffffc9000438b8d0 EFLAGS: 00010206
[   74.331676] RAX: 0000000000000000 RBX: ffff88007ad96300 RCX: 0000000000000000
[   74.332217] RDX: ffff88007fc137a8 RSI: ffff88007fc0db28 RDI: 0001bf00000001be
[   74.332758] RBP: ffffc9000438b8d8 R08: 000000000005008f R09: 00000000000005f9
[   74.333274] R10: ffff88007d001700 R11: ffffffff820a8a4d R12: ffff88007ad96300
[   74.333787] R13: 0000000000000002 R14: ffff880036604000 R15: 000077ff80000000
[   74.334308] FS:  00007fc70d8a7b40(0000) GS:ffff88007fc00000(0000) knlGS:0000000000000000
[   74.334891] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   74.335314] CR2: 00007fff4144a710 CR3: 000000007ab56000 CR4: 00000000003406f0
[   74.335830] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   74.336373] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   74.336895] Call Trace:
[   74.337086]  skb_release_all+0xd/0x30
[   74.337356]  consume_skb+0x2c/0x90
[   74.337607]  free_unused_bufs+0x1ff/0x270 [virtio_net]
[   74.337988]  ? vp_synchronize_vectors+0x3b/0x60 [virtio_pci]
[   74.338398]  virtnet_xdp+0x21e/0x440 [virtio_net]
[   74.338741]  dev_change_xdp_fd+0x101/0x140
[   74.339048]  do_setlink+0xcf4/0xd20
[   74.339304]  ? symcmp+0xf/0x20
[   74.339529]  ? mls_level_isvalid+0x52/0x60
[   74.339828]  ? mls_range_isvalid+0x43/0x50
[   74.340135]  ? nla_parse+0xa0/0x100
[   74.340400]  rtnl_setlink+0xd4/0x120
[   74.340664]  ? cpumask_next_and+0x30/0x50
[   74.340966]  rtnetlink_rcv_msg+0x7f/0x1f0
[   74.341259]  ? sock_has_perm+0x59/0x60
[   74.341586]  ? napi_consume_skb+0xe2/0x100
[   74.342010]  ? rtnl_newlink+0x890/0x890
[   74.342435]  netlink_rcv_skb+0x92/0xb0
[   74.342846]  rtnetlink_rcv+0x23/0x30
[   74.343277]  netlink_unicast+0x162/0x210
[   74.343677]  netlink_sendmsg+0x2db/0x390
[   74.343968]  sock_sendmsg+0x33/0x40
[   74.344233]  SYSC_sendto+0xee/0x160
[   74.344482]  ? SYSC_bind+0xb0/0xe0
[   74.344806]  ? sock_alloc_file+0x92/0x110
[   74.345106]  ? fd_install+0x20/0x30
[   74.345360]  ? sock_map_fd+0x3f/0x60
[   74.345586]  SyS_sendto+0x9/0x10
[   74.345790]  entry_SYSCALL_64_fastpath+0x1a/0xa9
[   74.346086] RIP: 0033:0x7fc70d1b8f6d
[   74.346312] RSP: 002b:00007fff4144a708 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
[   74.346785] RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 00007fc70d1b8f6d
[   74.347244] RDX: 000000000000002c RSI: 00007fff4144a720 RDI: 0000000000000003
[   74.347683] RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000
[   74.348544] R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff4144bd90
[   74.349082] R13: 0000000000000002 R14: 0000000000000002 R15: 00007fff4144cda0
[   74.349607] Code: 00 00 00 55 48 89 e5 53 48 89 fb 48 8b 7f 58 48 85 ff 74 0e 40 f6 c7 01 74 3d 48 c7 43 58 00 00 00 00 48 8b 7b 68 48 85 ff 74 05 <f0> ff 0f 74 20 48 8b 43 60 48 85 c0 74 14 65 8b 15 f3 ab 8d 7e
[   74.351008] RIP: skb_release_head_state+0x28/0x80 RSP: ffffc9000438b8d0
[   74.351625] ---[ end trace fe6e19fd11cfc80b ]---

Fixes: 2de2f7f40e ("virtio_net: XDP support for adjust_head")
Cc: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-20 22:22:20 -05:00
Jason Wang
61845d2072 virtio-net: batch stats updating
We already have counters for sent/recv packets and sent/recv bytes.
Doing a batched update to reduce the number of
u64_stats_update_begin/end().

Take care not to bother with stats update when called
speculatively.

Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-19 18:15:23 -05:00
John Fastabend
2de2f7f40e virtio_net: XDP support for adjust_head
Add support for XDP adjust head by allocating a 256B header region
that XDP programs can grow into. This is only enabled when a XDP
program is loaded.

In order to ensure that we do not have to unwind queue headroom push
queue setup below bpf_prog_add. It reads better to do a prog ref
unwind vs another queue setup call.

At the moment this code must do a full reset to ensure old buffers
without headroom on program add or with headroom on program removal
are not used incorrectly in the datapath. Ideally we would only
have to disable/enable the RX queues being updated but there is no
API to do this at the moment in virtio so use the big hammer. In
practice it is likely not that big of a problem as this will only
happen when XDP is enabled/disabled changing programs does not
require the reset. There is some risk that the driver may either
have an allocation failure or for some reason fail to correctly
negotiate with the underlying backend in this case the driver will
be left uninitialized. I have not seen this ever happen on my test
systems and for what its worth this same failure case can occur
from probe and other contexts in virtio framework.

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-07 10:05:12 -05:00
John Fastabend
9fe7bfce8b virtio_net: refactor freeze/restore logic into virtnet reset logic
For XDP we will need to reset the queues to allow for buffer headroom
to be configured. In order to do this we need to essentially run the
freeze()/restore() code path. Unfortunately the locking requirements
between the freeze/restore and reset paths are different however so
we can not simply reuse the code.

This patch refactors the code path and adds a reset helper routine.

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-07 10:05:12 -05:00
John Fastabend
722d82830a virtio_net: remove duplicate queue pair binding in XDP
Factor out qp assignment.

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-07 10:05:11 -05:00
John Fastabend
0354e4d19c virtio_net: factor out xdp handler for readability
At this point the do_xdp_prog is mostly if/else branches handling
the different modes of virtio_net. So remove it and handle running
the program in the per mode handlers.

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-07 10:05:11 -05:00
John Fastabend
473153291b virtio_net: wrap rtnl_lock in test for calling with lock already held
For XDP use case and to allow ethtool reset tests it is useful to be
able to use reset paths from contexts where rtnl lock is already
held.

This requries updating virtnet_set_queues and free_receive_bufs the
two places where rtnl_lock is taken in virtio_net. To do this we
use the following pattern,

	_foo(...) { do stuff }
	foo(...) { rtnl_lock(); _foo(...); rtnl_unlock()};

this allows us to use freeze()/restore() flow from both contexts.

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-07 10:05:11 -05:00
Eric Dumazet
4d6308aac3 virtio_net: exploit napi_complete_done() return value
Since commit 364b605573 ("net: busy-poll: return busypolling status to
drivers"), napi_complete_done() returns a boolean that can be used
by drivers to conditionally rearm interrupts.

This patch changes virtio_net to use this boolean to avoid a bit of
overhead for busy-poll users.

Jason reports about 1.1% improvement for 1 byte TCP_RR (burst 100).

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-04 19:38:28 -05:00
Eric Dumazet
ceef438d61 virtio_net: remove custom busy_poll
Generic NAPI busy polling allows us to remove custom implementations
found in drivers.

It is possible further optimization could be done by testing
napi_complete_done() return value.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-03 11:13:55 -05:00
David S. Miller
4e8f2fc1a5 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Two trivial overlapping changes conflicts in MPLS and mlx5.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-28 10:33:06 -05:00
Jakub Kicinski
529ec6ac26 virtio_net: reject XDP programs using header adjustment
commit 17bedab272 ("bpf: xdp: Allow head adjustment in XDP prog")
added a new XDP helper to prepend and remove data from a frame.
Make virtio_net reject programs making use of this helper until
proper support is added.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-25 22:48:40 -05:00
John Fastabend
b68df01560 virtio_net: use dev_kfree_skb for small buffer XDP receive
In the small buffer case during driver unload we currently use
put_page instead of dev_kfree_skb. Resolve this by adding a check
for virtnet mode when checking XDP queue type. Also name the
function so that the code reads correctly to match the additional
check.

Fixes: bb91accf27 ("virtio-net: XDP support for small buffers")
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-25 22:48:17 -05:00
Daniel Borkmann
a67edbf4fb bpf: add initial bpf tracepoints
This work adds a number of tracepoints to paths that are either
considered slow-path or exception-like states, where monitoring or
inspecting them would be desirable.

For bpf(2) syscall, tracepoints have been placed for main commands
when they succeed. In XDP case, tracepoint is for exceptions, that
is, f.e. on abnormal BPF program exit such as unknown or XDP_ABORTED
return code, or when error occurs during XDP_TX action and the packet
could not be forwarded.

Both have been split into separate event headers, and can be further
extended. Worst case, if they unexpectedly should get into our way in
future, they can also removed [1]. Of course, these tracepoints (like
any other) can be analyzed by eBPF itself, etc. Example output:

  # ./perf record -a -e bpf:* sleep 10
  # ./perf script
  sock_example  6197 [005]   283.980322:      bpf:bpf_map_create: map type=ARRAY ufd=4 key=4 val=8 max=256 flags=0
  sock_example  6197 [005]   283.980721:       bpf:bpf_prog_load: prog=a5ea8fa30ea6849c type=SOCKET_FILTER ufd=5
  sock_example  6197 [005]   283.988423:   bpf:bpf_prog_get_type: prog=a5ea8fa30ea6849c type=SOCKET_FILTER
  sock_example  6197 [005]   283.988443: bpf:bpf_map_lookup_elem: map type=ARRAY ufd=4 key=[06 00 00 00] val=[00 00 00 00 00 00 00 00]
  [...]
  sock_example  6197 [005]   288.990868: bpf:bpf_map_lookup_elem: map type=ARRAY ufd=4 key=[01 00 00 00] val=[14 00 00 00 00 00 00 00]
       swapper     0 [005]   289.338243:    bpf:bpf_prog_put_rcu: prog=a5ea8fa30ea6849c type=SOCKET_FILTER

  [1] https://lwn.net/Articles/705270/

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-25 13:17:47 -05:00
Michael S. Tsirkin
d0fa28f000 virtio_net: fix PAGE_SIZE > 64k
I don't have any guests with PAGE_SIZE > 64k but the
code seems to be clearly broken in that case
as PAGE_SIZE / MERGEABLE_BUFFER_ALIGN will need
more than 8 bit and so the code in mergeable_ctx_to_buf_address
does not give us the actual true size.

Cc: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-24 14:41:06 -05:00
Jason Wang
6391a4481b virtio-net: restore VIRTIO_HDR_F_DATA_VALID on receiving
Commit 501db51139 ("virtio: don't set VIRTIO_NET_HDR_F_DATA_VALID on
xmit") in fact disables VIRTIO_HDR_F_DATA_VALID on receiving path too,
fixing this by adding a hint (has_data_valid) and set it only on the
receiving path.

Cc: Rolf Neugebauer <rolf.neugebauer@docker.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Rolf Neugebauer <rolf.neugebauer@docker.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-20 11:01:17 -05:00
stephen hemminger
bc1f44709c net: make ndo_get_stats64 a void function
The network device operation for reading statistics is only called
in one place, and it ignores the return value. Having a structure
return value is potentially confusing because some future driver could
incorrectly assume that the return value was used.

Fix all drivers with ndo_get_stats64 to have a void function.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-08 17:51:44 -05:00
Shyam Saini
801822d1be net: Use kmemdup instead of kmalloc and memcpy
when some other buffer is immediately copied into allocated region.
Replace calls to kmalloc followed by a memcpy with a direct
call to kmemdup.

Signed-off-by: Shyam Saini <mayhs11saini@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-29 11:37:14 -05:00
Thomas Gleixner
73c1b41e63 cpu/hotplug: Cleanup state names
When the state names got added a script was used to add the extra argument
to the calls. The script basically converted the state constant to a
string, but the cleanup to convert these strings into meaningful ones did
not happen.

Replace all the useless strings with 'subsys/xxx/yyy:state' strings which
are used in all the other places already.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Link: http://lkml.kernel.org/r/20161221192112.085444152@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-25 10:47:44 +01:00
Jason Wang
bb91accf27 virtio-net: XDP support for small buffers
Commit f600b69050 ("virtio_net: Add XDP support") leaves the case of
small receive buffer untouched. This will confuse the user who want to
set XDP but use small buffers. Other than forbid XDP in small buffer
mode, let's make it work. XDP then can only work at skb->data since
virtio-net create skbs during refill, this is sub optimal which could
be optimized in the future.

Cc: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-23 13:48:56 -05:00
Jason Wang
c47a43d300 virtio-net: remove big packet XDP codes
Now we in fact don't allow XDP for big packets, remove its codes.

Cc: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-23 13:48:55 -05:00
Jason Wang
92502fe86c virtio-net: forbid XDP when VIRTIO_NET_F_GUEST_UFO is support
When VIRTIO_NET_F_GUEST_UFO is negotiated, host could still send UFO
packet that exceeds a single page which could not be handled
correctly by XDP. So this patch forbids setting XDP when GUEST_UFO is
supported. While at it, forbid XDP for ECN (which comes only from GRO)
too to prevent user from misconfiguration.

Cc: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-23 13:48:55 -05:00
Jason Wang
5c33474d41 virtio-net: make rx buf size estimation works for XDP
We don't update ewma rx buf size in the case of XDP. This will lead
underestimation of rx buf size which causes host to produce more than
one buffers. This will greatly increase the possibility of XDP page
linearization.

Cc: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-23 13:48:55 -05:00
Jason Wang
b00f70b0da virtio-net: unbreak csumed packets for XDP_PASS
We drop csumed packet when do XDP for packets. This breaks
XDP_PASS when GUEST_CSUM is supported. Fix this by allowing csum flag
to be set. With this patch, simple TCP works for XDP_PASS.

Cc: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-23 13:48:54 -05:00
Jason Wang
1830f8935f virtio-net: correctly handle XDP_PASS for linearized packets
When XDP_PASS were determined for linearized packets, we try to get
new buffers in the virtqueue and build skbs from them. This is wrong,
we should create skbs based on existed buffers instead. Fixing them by
creating skb based on xdp_page.

With this patch "ping 192.168.100.4 -s 3900 -M do" works for XDP_PASS.

Cc: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-23 13:48:54 -05:00
Jason Wang
56a86f84b8 virtio-net: fix page miscount during XDP linearizing
We don't put page during linearizing, the would cause leaking when
xmit through XDP_TX or the packet exceeds PAGE_SIZE. Fix them by
put page accordingly. Also decrease the number of buffers during
linearizing to make sure caller can free buffers correctly when packet
exceeds PAGE_SIZE. With this patch, we won't get OOM after linearize
huge number of packets.

Cc: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-23 13:48:54 -05:00
Jason Wang
275be061b3 virtio-net: correctly xmit linearized page on XDP_TX
After we linearize page, we should xmit this page instead of the page
of first buffer which may lead unexpected result. With this patch, we
can see correct packet during XDP_TX.

Cc: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-23 13:48:54 -05:00
Jason Wang
73b62bd085 virtio-net: remove the warning before XDP linearizing
Since we use EWMA to estimate the size of rx buffer. When rx buffer
size is underestimated, it's usual to have a packet with more than one
buffers. Consider this is not a bug, remove the warning and correct
the comment before XDP linearizing.

Cc: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-23 13:48:53 -05:00
John Fastabend
72979a6c35 virtio_net: xdp, add slowpath case for non contiguous buffers
virtio_net XDP support expects receive buffers to be contiguous.
If this is not the case we enable a slowpath to allow connectivity
to continue but at a significan performance overhead associated with
linearizing data. To make it painfully aware to users that XDP is
running in a degraded mode we throw an xdp buffer error.

To linearize packets we allocate a page and copy the segments of
the data, including the header, into it. After this the page can be
handled by XDP code flow as normal.

Then depending on the return code the page is either freed or sent
to the XDP xmit path. There is no attempt to optimize this path.

This case is being handled simple as a precaution in case some
unknown backend were to generate packets in this form. To test this
I had to hack qemu and force it to generate these packets. I do not
expect this case to be generated by "real" backends.

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-17 11:48:55 -05:00
John Fastabend
56434a01b1 virtio_net: add XDP_TX support
This adds support for the XDP_TX action to virtio_net. When an XDP
program is run and returns the XDP_TX action the virtio_net XDP
implementation will transmit the packet on a TX queue that aligns
with the current CPU that the XDP packet was processed on.

Before sending the packet the header is zeroed.  Also XDP is expected
to handle checksum correctly so no checksum offload  support is
provided.

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-17 11:48:55 -05:00
John Fastabend
672aafd5d8 virtio_net: add dedicated XDP transmit queues
XDP requires using isolated transmit queues to avoid interference
with normal networking stack (BQL, NETDEV_TX_BUSY, etc). This patch
adds a XDP queue per cpu when a XDP program is loaded and does not
expose the queues to the OS via the normal API call to
netif_set_real_num_tx_queues(). This way the stack will never push
an skb to these queues.

However virtio/vhost/qemu implementation only allows for creating
TX/RX queue pairs at this time so creating only TX queues was not
possible. And because the associated RX queues are being created I
went ahead and exposed these to the stack and let the backend use
them. This creates more RX queues visible to the network stack than
TX queues which is worth mentioning but does not cause any issues as
far as I can tell.

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-17 11:48:55 -05:00
John Fastabend
f600b69050 virtio_net: Add XDP support
This adds XDP support to virtio_net. Some requirements must be
met for XDP to be enabled depending on the mode. First it will
only be supported with LRO disabled so that data is not pushed
across multiple buffers. Second the MTU must be less than a page
size to avoid having to handle XDP across multiple pages.

If mergeable receive is enabled this patch only supports the case
where header and data are in the same buf which we can check when
a packet is received by looking at num_buf. If the num_buf is
greater than 1 and a XDP program is loaded the packet is dropped
and a warning is thrown. When any_header_sg is set this does not
happen and both header and data is put in a single buffer as expected
so we check this when XDP programs are loaded.  Subsequent patches
will process the packet in a degraded mode to ensure connectivity
and correctness is not lost even if backend pushes packets into
multiple buffers.

If big packets mode is enabled and MTU/LRO conditions above are
met then XDP is allowed.

This patch was tested with qemu with vhost=on and vhost=off where
mergeable and big_packet modes were forced via hard coding feature
negotiation. Multiple buffers per packet was forced via a small
test patch to vhost.c in the vhost=on qemu mode.

Suggested-by: Shrijeet Mukherjee <shrijeet@gmail.com>
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-17 11:48:55 -05:00
Jason Wang
a220871be6 virtio-net: correctly enable multiqueue
Commit 4490001029 ("virtio-net: enable
multiqueue by default") blindly set the affinity instead of queues
during probe which can cause a mismatch of #queues between guest and
host. This patch fixes it by setting queues.

Reported-by: Theodore Ts'o <tytso@mit.edu>
Tested-by: Theodore Ts'o <tytso@mit.edu>
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Fixes: 49000102901 ("virtio-net: enable multiqueue by default")
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-13 10:37:38 -05:00
David S. Miller
c63d352f05 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-12-06 21:33:19 -05:00
Andy Lutomirski
e37e2ff350 virtio-net: Fix DMA-from-the-stack in virtnet_set_mac_address()
With CONFIG_VMAP_STACK=y, virtnet_set_mac_address() can be passed a
pointer to the stack and it will OOPS.  Copy the address to the heap
to prevent the crash.

Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Laura Abbott <labbott@redhat.com>
Reported-by: zbyszek@in.waw.pl
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-06 11:38:43 -05:00
Jason Wang
4490001029 virtio-net: enable multiqueue by default
We use single queue even if multiqueue is enabled and let admin to
enable it through ethtool later. This is used to avoid possible
regression (small packet TCP stream transmission). But looks like an
overkill since:

- single queue user can disable multiqueue when launching qemu
- brings extra troubles for the management since it needs extra admin
  tool in guest to enable multiqueue
- multiqueue performs much better than single queue in most of the
  cases

So this patch enables multiqueue by default: if #queues is less than or
equal to #vcpu, enable as much as queue pairs; if #queues is greater
than #vcpu, enable #vcpu queue pairs.

Cc: Hannes Frederic Sowa <hannes@redhat.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Neil Horman <nhorman@redhat.com>
Cc: Jeremy Eder <jeder@redhat.com>
Cc: Marko Myllynen <myllynen@redhat.com>
Cc: Maxime Coquelin <maxime.coquelin@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-28 13:17:40 -05:00