Граф коммитов

106 Коммитов

Автор SHA1 Сообщение Дата
Linus Torvalds 70e71ca0af Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:

 1) New offloading infrastructure and example 'rocker' driver for
    offloading of switching and routing to hardware.

    This work was done by a large group of dedicated individuals, not
    limited to: Scott Feldman, Jiri Pirko, Thomas Graf, John Fastabend,
    Jamal Hadi Salim, Andy Gospodarek, Florian Fainelli, Roopa Prabhu

 2) Start making the networking operate on IOV iterators instead of
    modifying iov objects in-situ during transfers.  Thanks to Al Viro
    and Herbert Xu.

 3) A set of new netlink interfaces for the TIPC stack, from Richard
    Alpe.

 4) Remove unnecessary looping during ipv6 routing lookups, from Martin
    KaFai Lau.

 5) Add PAUSE frame generation support to gianfar driver, from Matei
    Pavaluca.

 6) Allow for larger reordering levels in TCP, which are easily
    achievable in the real world right now, from Eric Dumazet.

 7) Add a variable of napi_schedule that doesn't need to disable cpu
    interrupts, from Eric Dumazet.

 8) Use a doubly linked list to optimize neigh_parms_release(), from
    Nicolas Dichtel.

 9) Various enhancements to the kernel BPF verifier, and allow eBPF
    programs to actually be attached to sockets.  From Alexei
    Starovoitov.

10) Support TSO/LSO in sunvnet driver, from David L Stevens.

11) Allow controlling ECN usage via routing metrics, from Florian
    Westphal.

12) Remote checksum offload, from Tom Herbert.

13) Add split-header receive, BQL, and xmit_more support to amd-xgbe
    driver, from Thomas Lendacky.

14) Add MPLS support to openvswitch, from Simon Horman.

15) Support wildcard tunnel endpoints in ipv6 tunnels, from Steffen
    Klassert.

16) Do gro flushes on a per-device basis using a timer, from Eric
    Dumazet.  This tries to resolve the conflicting goals between the
    desired handling of bulk vs.  RPC-like traffic.

17) Allow userspace to ask for the CPU upon what a packet was
    received/steered, via SO_INCOMING_CPU.  From Eric Dumazet.

18) Limit GSO packets to half the current congestion window, from Eric
    Dumazet.

19) Add a generic helper so that all drivers set their RSS keys in a
    consistent way, from Eric Dumazet.

20) Add xmit_more support to enic driver, from Govindarajulu
    Varadarajan.

21) Add VLAN packet scheduler action, from Jiri Pirko.

22) Support configurable RSS hash functions via ethtool, from Eyal
    Perry.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1820 commits)
  Fix race condition between vxlan_sock_add and vxlan_sock_release
  net/macb: fix compilation warning for print_hex_dump() called with skb->mac_header
  net/mlx4: Add support for A0 steering
  net/mlx4: Refactor QUERY_PORT
  net/mlx4_core: Add explicit error message when rule doesn't meet configuration
  net/mlx4: Add A0 hybrid steering
  net/mlx4: Add mlx4_bitmap zone allocator
  net/mlx4: Add a check if there are too many reserved QPs
  net/mlx4: Change QP allocation scheme
  net/mlx4_core: Use tasklet for user-space CQ completion events
  net/mlx4_core: Mask out host side virtualization features for guests
  net/mlx4_en: Set csum level for encapsulated packets
  be2net: Export tunnel offloads only when a VxLAN tunnel is created
  gianfar: Fix dma check map error when DMA_API_DEBUG is enabled
  cxgb4/csiostor: Don't use MASTER_MUST for fw_hello call
  net: fec: only enable mdio interrupt before phy device link up
  net: fec: clear all interrupt events to support i.MX6SX
  net: fec: reset fep link status in suspend function
  net: sock: fix access via invalid file descriptor
  net: introduce helper macro for_each_cmsghdr
  ...
2014-12-11 14:27:06 -08:00
Al Viro c0371da604 put iov_iter into msghdr
Note that the code _using_ ->msg_iter at that point will be very
unhappy with anything other than unshifted iovec-backed iov_iter.
We still need to convert users to proper primitives.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-12-09 16:29:03 -05:00
Michael S. Tsirkin 41e3e42108 vhost/net: enable virtio 1.0
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-09 12:05:30 +02:00
Michael S. Tsirkin e4fca7d6ff vhost/net: larger header for virtio 1.0
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2014-12-09 12:05:30 +02:00
Michael S. Tsirkin 8b38694a2d vhost/net: virtio 1.0 byte swap
I had to add an explicit tag to suppress compiler warning:
gcc isn't smart enough to notice that
len is always initialized since function is called with size > 0.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2014-12-09 12:05:29 +02:00
Michael S. Tsirkin bf99573496 vhost/net: force len for TX to host endian
vhost/net keeps a copy of the used ring in host memory but (ab)uses
the length field for internal house-keeping. This works because the
length in the used ring for tx is always 0. In order to suppress sparse
warnings, we force native endianness here.
Note that these values are never exposed to guests.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Jason Wang <jasowang@redhat.com>
2014-12-09 12:05:29 +02:00
Romain Francoise d04257b07f vhost-net: don't open-code kvfree
Commit 23cc5a991c ("vhost-net: extend device allocation to vmalloc")
added another open-coded version of kvfree (which is available since
v3.15-rc5), nuke it.

Signed-off-by: Romain Francoise <romain@orebokech.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-06-23 09:22:48 +03:00
Michael S. Tsirkin 47283bef7e vhost: move memory pointer to VQs
commit 2ae76693b8bcabf370b981cd00c36cd41d33fabc
    vhost: replace rcu with mutex
replaced rcu sync for memory accesses with VQ mutex locl/unlock.
This is correct since all accesses are under VQ mutex, but incomplete:
we still do useless rcu lock/unlock operations, someone might copy this
code into some other context where this won't be right.
This use of RCU is also non standard and hard to understand.
Let's copy the pointer to each VQ structure, this way
the access rules become straight-forward, and there's
no need for RCU anymore.

Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-06-09 16:21:07 +03:00
Michael S. Tsirkin ea16c51433 vhost: move acked_features to VQs
Refactor code to make sure features are only accessed
under VQ mutex. This makes everything simpler, no need
for RCU here anymore.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-06-09 16:21:06 +03:00
Michael S. Tsirkin 23cc5a991c vhost-net: extend device allocation to vmalloc
Michael Mueller provided a patch to reduce the size of
vhost-net structure as some allocations could fail under
memory pressure/fragmentation. We are still left with
high order allocations though.

This patch is handling the problem at the core level, allowing
vhost structures to use vmalloc() if kmalloc() failed.

As vmalloc() adds overhead on a critical network path, add __GFP_REPEAT
to kzalloc() flags to do this fallback only when really needed.

People are still looking at cleaner ways to handle the problem
at the API level, probably passing in multiple iovecs.
This hack seems consistent with approaches
taken since then by drivers/vhost/scsi.c and net/core/dev.c

Based on patch by Romain Francoise.

Cc: Michael Mueller <mimu@linux.vnet.ibm.com>
Signed-off-by: Romain Francoise <romain@orebokech.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
2014-06-09 16:21:05 +03:00
Al Viro 09aaacf02a vhost: don't open-code sockfd_put()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-04-01 23:19:10 -04:00
Michael S. Tsirkin a39ee449f9 vhost: validate vhost_get_vq_desc return value
vhost fails to validate negative error code
from vhost_get_vq_desc causing
a crash: we are using -EFAULT which is 0xfffffff2
as vector size, which exceeds the allocated size.

The code in question was introduced in commit
8dd014adfe
    vhost-net: mergeable buffers support

CVE-2014-0055

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-28 16:10:35 -04:00
Michael S. Tsirkin d8316f3991 vhost: fix total length when packets are too short
When mergeable buffers are disabled, and the
incoming packet is too large for the rx buffer,
get_rx_bufs returns success.

This was intentional in order for make recvmsg
truncate the packet and then handle_rx would
detect err != sock_len and drop it.

Unfortunately we pass the original sock_len to
recvmsg - which means we use parts of iov not fully
validated.

Fix this up by detecting this overrun and doing packet drop
immediately.

CVE-2014-0077

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-28 16:07:31 -04:00
Michael S. Tsirkin b0c057ca7e vhost: fix a theoretical race in device cleanup
vhost_zerocopy_callback accesses VQ right after it drops a ubuf
reference.  In theory, this could race with device removal which waits
on the ubuf kref, and crash on use after free.

Do all accesses within rcu read side critical section, and synchronize
on release.

Since callbacks are always invoked from bh, synchronize_rcu_bh seems
enough and will help release complete a bit faster.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-13 18:47:30 -05:00
Michael S. Tsirkin 0ad8b480d6 vhost: fix ref cnt checking deadlock
vhost checked the counter within the refcnt before decrementing.  It
really wanted to know that it is the one that has the last reference, as
a way to batch freeing resources a bit more efficiently.

Note: we only let refcount go to 0 on device release.

This works well but we now access the ref counter twice so there's a
race: all users might see a high count and decide to defer freeing
resources.
In the end no one initiates freeing resources until the last reference
is gone (which is on VM shotdown so might happen after a looooong time).

Let's do what we probably should have done straight away:
switch from kref to plain atomic, documenting the
semantics, return the refcount value atomically after decrement,
then use that to avoid the deadlock.

Reported-by: Qin Chuanyu <qinchuanyu@huawei.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-13 18:47:30 -05:00
Zhi Yong Wu 59566b6e8c vhost: remove the dead branch
Since vhost_dev_init() forever return 0, some branches are never run,
therefore need to be removed.

Signed-off-by: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-06 15:22:05 -05:00
Jason Wang f7c6be404d vhost_net: correctly limit the max pending buffers
As Michael point out, We used to limit the max pending DMAs to get better cache
utilization. But it was not done correctly since it was one done when there's no
new buffers submitted from guest. Guest can easily exceeds the limitation by
keeping sending packets.

So this patch moves the check into main loop. Tests shows about 5%-10%
improvement on per cpu throughput for guest tx.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-03 22:46:58 -04:00
Jason Wang 19c73b3e08 vhost_net: poll vhost queue after marking DMA is done
We used to poll vhost queue before making DMA is done, this is racy if vhost
thread were waked up before marking DMA is done which can result the signal to
be missed. Fix this by always polling the vhost thread before DMA is done.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-03 22:46:57 -04:00
Jason Wang ce21a02913 vhost_net: determine whether or not to use zerocopy at one time
Currently, even if the packet length is smaller than VHOST_GOODCOPY_LEN, if
upend_idx != done_idx we still set zcopy_used to true and rollback this choice
later. This could be avoided by determining zerocopy once by checking all
conditions at one time before.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-03 22:46:57 -04:00
Jason Wang c92112aed3 vhost_net: use vhost_add_used_and_signal_n() in vhost_zerocopy_signal_used()
We tend to batch the used adding and signaling in vhost_zerocopy_callback()
which may result more than 100 used buffers to be updated in
vhost_zerocopy_signal_used() in some cases. So switch to use
vhost_add_used_and_signal_n() to avoid multiple calls to
vhost_add_used_and_signal(). Which means much less times of used index
updating and memory barriers.

2% performance improvement were seen on netperf TCP_RR test.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-03 22:46:57 -04:00
Jason Wang 094afe7d55 vhost_net: make vhost_zerocopy_signal_used() return void
None of its caller use its return value, so let it return void.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-03 22:46:57 -04:00
Asias He 22fa90c7fb vhost: Remove custom vhost rcu usage
Now, vq->private_data is always accessed under vq mutex. No need to play
the vhost rcu trick.

Signed-off-by: Asias He <asias@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2013-07-11 15:38:40 +03:00
Asias He 2e26af79b7 vhost-net: Always access vq->private_data under vq mutex
Signed-off-by: Asias He <asias@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2013-07-11 15:36:45 +03:00
Asias He 0a1febf7ba vhost: Make local function static
$ make C=1 M=drivers/vhost

drivers/vhost/net.c:168:5: warning: symbol 'vhost_net_set_ubuf_info' was not declared. Should it be static?
drivers/vhost/net.c:194:6: warning: symbol 'vhost_net_vq_reset' was not declared. Should it be static?
drivers/vhost/scsi.c:219:6: warning: symbol 'tcm_vhost_done_inflight' was not declared. Should it be static?

Signed-off-by: Asias He <asias@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2013-07-07 17:34:07 +03:00
Michael S. Tsirkin c38e39c378 vhost-net: fix use-after-free in vhost_net_flush
vhost_net_ubuf_put_and_wait has a confusing name:
it will actually also free it's argument.
Thus since commit 1280c27f8e
    "vhost-net: flush outstanding DMAs on memory change"
vhost_net_flush tries to use the argument after passing it
to vhost_net_ubuf_put_and_wait, this results
in use after free.
To fix, don't free the argument in vhost_net_ubuf_put_and_wait,
add an new API for callers that want to free ubufs.

Acked-by: Asias He <asias@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2013-07-07 14:06:22 +03:00
Michael S. Tsirkin 288cfe78c8 vhost: fix ubuf_info cleanup
vhost_net_clear_ubuf_info didn't clear ubuf_info
after kfree, this could trigger double free.
Fix this and simplify this code to make it more robust: make sure
ubuf info is always freed through vhost_net_clear_ubuf_info.

Reported-by: Tommi Rantala <tt.rantala@gmail.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-11 02:46:21 -07:00
Michael S. Tsirkin 05c0535194 vhost: check owner before we overwrite ubuf_info
If device has an owner, we shouldn't touch ubuf_info
since it might be in use.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-11 02:46:21 -07:00
Jason Wang 4364d5f96e vhost_net: clear msg.control for non-zerocopy case during tx
When we decide not use zero-copy, msg.control should be set to NULL otherwise
macvtap/tap may set zerocopy callbacks which may decrease the kref of ubufs
wrongly.

Bug were introduced by commit cedb9bdce0
(vhost-net: skip head management if no outstanding).

This solves the following warnings:

WARNING: at include/linux/kref.h:47 handle_tx+0x477/0x4b0 [vhost_net]()
Modules linked in: vhost_net macvtap macvlan tun nfsd exportfs bridge stp llc openvswitch kvm_amd kvm bnx2 megaraid_sas [last unloaded: tun]
CPU: 5 PID: 8670 Comm: vhost-8668 Not tainted 3.10.0-rc2+ #1566
Hardware name: Dell Inc. PowerEdge R715/00XHKG, BIOS 1.5.2 04/19/2011
ffffffffa0198323 ffff88007c9ebd08 ffffffff81796b73 ffff88007c9ebd48
ffffffff8103d66b 000000007b773e20 ffff8800779f0000 ffff8800779f43f0
ffff8800779f8418 000000000000015c 0000000000000062 ffff88007c9ebd58
Call Trace:
[<ffffffff81796b73>] dump_stack+0x19/0x1e
[<ffffffff8103d66b>] warn_slowpath_common+0x6b/0xa0
[<ffffffff8103d6b5>] warn_slowpath_null+0x15/0x20
[<ffffffffa0197627>] handle_tx+0x477/0x4b0 [vhost_net]
[<ffffffffa0197690>] handle_tx_kick+0x10/0x20 [vhost_net]
[<ffffffffa019541e>] vhost_worker+0xfe/0x1a0 [vhost_net]
[<ffffffffa0195320>] ? vhost_attach_cgroups_work+0x30/0x30 [vhost_net]
[<ffffffffa0195320>] ? vhost_attach_cgroups_work+0x30/0x30 [vhost_net]
[<ffffffff81061f46>] kthread+0xc6/0xd0
[<ffffffff81061e80>] ? kthread_freezable_should_stop+0x70/0x70
[<ffffffff817a1aec>] ret_from_fork+0x7c/0xb0
[<ffffffff81061e80>] ? kthread_freezable_should_stop+0x70/0x70

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>
2013-06-10 14:31:45 -07:00
Asias He fe729a57c8 vhost-net: Cleanup vhost_ubuf and vhost_zcopy
- Rename vhost_ubuf to vhost_net_ubuf
- Rename vhost_zcopy_mask to vhost_net_zcopy_mask
- Make funcs static

Signed-off-by: Asias He <asias@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2013-05-06 13:25:47 +03:00
Asias He 8570a6e72c vhost: Move VHOST_NET_FEATURES to net.c
vhost.h should not depend on device specific marcos like
VHOST_NET_F_VIRTIO_NET_HDR and VIRTIO_NET_F_MRG_RXBUF.

Signed-off-by: Asias He <asias@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2013-05-06 13:21:00 +03:00
Asias He b1ad8496c9 vhost-net: Free ubuf when vhost_dev_set_owner fails
Signed-off-by: Asias He <asias@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2013-05-06 12:57:54 +03:00
Michael S. Tsirkin 150b9e51ae vhost: fix error handling in RESET_OWNER ioctl
RESET_OWNER ioctl would leave the fd in a bad state if
memory allocation failed: device is stopped
but owner is not reset. Make state changes
after allocating memory, such that a failed
ioctl has no effect.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2013-05-01 10:02:54 +03:00
Michael S. Tsirkin 81f95a5580 vhost: move per-vq net specific fields out to net
This will remove the need for vhost scsi to pull
in virtio-net.h.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2013-05-01 10:02:53 +03:00
Asias He 2839400f8f vhost: move vhost-net zerocopy fields to net.c
On top of 'vhost: Allow device specific fields per vq', we can move device
specific fields to device virt queue from vhost virt queue.

Signed-off-by: Asias He <asias@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2013-05-01 10:02:52 +03:00
Asias He 3ab2e420ec vhost: Allow device specific fields per vq
This is useful for any device who wants device specific fields per vq.
For example, tcm_vhost wants a per vq field to track requests which are
in flight on the vq. Also, on top of this we can add patches to move
things like ubufs from vhost.h out to net.c.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Asias He <asias@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2013-05-01 10:02:45 +03:00
Jason Wang 70181d5120 vhost_net: remove tx polling state
After commit 2b8b328b61 (vhost_net: handle polling
errors when setting backend), we in fact track the polling state through
poll->wqh, so there's no need to duplicate the work with an extra
vhost_net_polling_state. So this patch removes this and make the code simpler.

This patch also removes the all tx starting/stopping code in tx path according
to Michael's suggestion.

Netperf test shows almost the same result in stream test, but gets improvements
on TCP_RR tests (both zerocopy or copy) especially on low load cases.

Tested between multiqueue kvm guest and external host with two direct
connected 82599s.

zerocopy disabled:

sessions|transaction rates|normalize|
before/after/+improvements
1 | 9510.24/11727.29/+23.3%    | 693.54/887.68/+28.0%   |
25| 192931.50/241729.87/+25.3% | 2376.80/2771.70/+16.6% |
50| 277634.64/291905.76/+5%    | 3118.36/3230.11/+3.6%  |

zerocopy enabled:

sessions|transaction rates|normalize|
before/after/+improvements
1 | 7318.33/11929.76/+63.0%    | 521.86/843.30/+61.6%   |
25| 167264.88/242422.15/+44.9% | 2181.60/2788.16/+27.8% |
50| 272181.02/294347.04/+8.1%  | 3071.56/3257.85/+6.1%  |

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>
2013-04-11 16:16:22 -04:00
Michael S. Tsirkin 46aa92d1ba vhost/net: fix heads usage of ubuf_info
ubuf info allocator uses guest controlled head as an index,
so a malicious guest could put the same head entry in the ring twice,
and we will get two callbacks on the same value.
To fix use upend_idx which is guaranteed to be unique.

Reported-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Cc: stable@kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-17 14:28:54 -04:00
Jason Wang 2b8b328b61 vhost_net: handle polling errors when setting backend
Currently, the polling errors were ignored, which can lead following issues:

- vhost remove itself unconditionally from waitqueue when stopping the poll,
  this may crash the kernel since the previous attempt of starting may fail to
  add itself to the waitqueue
- userspace may think the backend were successfully set even when the polling
  failed.

Solve this by:

- check poll->wqh before trying to remove from waitqueue
- report polling errors in vhost_poll_start(), tx_poll_start(), the return value
  will be checked and returned when userspace want to set the backend

After this fix, there still could be a polling failure after backend is set, it
will addressed by the next patch.

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>
2013-01-29 15:43:03 -05:00
Jason Wang 692a998b90 vhost_net: correct error handling in vhost_net_set_backend()
Currently, when vhost_init_used() fails the sock refcnt and ubufs were
leaked. Correct this by calling vhost_init_used() before assign ubufs and
restore the oldsock when it fails.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-01-29 15:43:03 -05:00
Michael S. Tsirkin f9611c43ab vhost-net: enable zerocopy tx by default
Zero copy TX has been around for a while now.
We seem to be down to eliminating theoretical bugs
and performance tuning at this point:
it's probably time to enable it by default so that
most users get the benefit.

Keep the flag around meanwhile so users can experiment
with disabling this if they experience regressions.
I expect that we will remove it in the future.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2012-12-06 17:09:18 +02:00
Michael S. Tsirkin cedb9bdce0 vhost-net: skip head management if no outstanding
For short packets zerocopy mode adds overhead
of managing heads which isn't necessary: we
could simly update used ring directly
same as with zerocopy disabled.

Things seem to run a bit faster if we detect
and bypass head management when zcopy isn't used.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2012-12-06 17:09:18 +02:00
Michael S. Tsirkin 1280c27f8e vhost-net: flush outstanding DMAs on memory change
When memory map changes, we need to flush outstanding
DMAs as they might in theory reference old memory addresses.
To do this simply stop initiating new DMAs
and wait for ubufs ref count to drop to 0.
Afterwards reset the count back to 1.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2012-12-06 17:09:18 +02:00
Michael S. Tsirkin 935cdee7ee vhost: avoid backend flush on vring ops
vring changes already do a flush internally where appropriate, so we do
not need a second flush.

It's currently not very expensive but a follow-up patch makes flush more
heavy-weight, so remove the extra flush here to avoid regressing
performance if call or kick fds are changed on data path.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2012-12-06 17:09:18 +02:00
Michael S. Tsirkin 64e9a9b8a0 vhost-net: initialize zcopy packet counters
These packet counters are used to drive the zercopy
selection heuristic so nothing too bad happens if they are off a bit -
and they are also reset once in a while.
But it's cleaner to clear them when backend is set so that
we start in a known state.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-12-03 13:42:17 -05:00
David S. Miller d4185bbf62 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c

Minor conflict between the BCM_CNIC define removal in net-next
and a bug fix added to net.  Based upon a conflict resolution
patch posted by Stephen Rothwell.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-10 18:32:51 -05:00
Michael S. Tsirkin 24eb21a148 vhost-net: reduce vq polling on tx zerocopy
It seems that to avoid deadlocks it is enough to poll vq before
 we are going to use the last buffer.  This is faster than
c70aa540c7.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-02 21:29:58 -04:00
Michael S. Tsirkin eaae8132ef vhost-net: select tx zero copy dynamically
Even when vhost-net is in zero-copy transmit mode,
net core might still decide to copy the skb later
which is somewhat slower than a copy in user
context: data copy overhead is added to the cost of
page pin/unpin. The result is that enabling tx zero copy
option leads to higher CPU utilization for guest to guest
and guest to host traffic.

To fix this, suppress zero copy tx after a given number of
packets triggered late data copy. Re-enable periodically
to detect workload changes.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-02 21:29:58 -04:00
Michael S. Tsirkin b211616d71 vhost: move -net specific code out
Zerocopy handling code is vhost-net specific.
Move it from vhost.c/vhost.h out to net.c

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-02 21:29:58 -04:00
Michael S. Tsirkin 70e4cb9aaf vhost-net: cleanup macros for DMA status tracking
Better document macros for DMA tracking. Add an
explicit one for DMA in progress instead of
relying on user supplying len != 1.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-02 21:29:57 -04:00
Michael S. Tsirkin 910a578f7e vhost: fix mergeable bufs on BE hosts
We copy head count to a 16 bit field, this works by chance on LE but on
BE guest gets 0. Fix it up.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Alexander Graf <agraf@suse.de>
Cc: stable@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-10-24 23:19:30 -04:00