Commit Graph

4 Commits

Author SHA1 Message Date
Jan Kiszka
4712c158c5 e1000e: Prevent MSI/MSI-X storms
Only signal MSI/MSI-X events on rising edges. So far we re-triggered the
interrupt sources even if the guest did no consumed the pending one,
easily causing interrupt storms.

Issue was observable with Linux 4.16 e1000e driver when MSI-X was used.
Vector 2 was causing interrupt storms after the driver activated the
device.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2018-07-20 08:30:48 +08:00
Ed Swierk via Qemu-devel
7d08c73e7b e1000, e1000e: Move per-packet TX offload flags out of context state
sum_needed and cptse flags are received from the guest within each
transmit data descriptor. They are not part of the offload context;
instead, they determine how to apply a previously received context to
the packet being transmitted:

- If cptse is set, perform both segmentation and checksum offload
  using the parameters in the TSO context; otherwise just do checksum
  offload. (Currently the e1000 device incorrectly stores only one
  context, which will be fixed in a subsequent patch.)

- Depending on the bits set in sum_needed, possibly perform L4
  checksum offload and/or IP checksum offload, using the parameters in
  the appropriate context.

Move these flags out of struct e1000x_txd_props, which is otherwise
dedicated to storing values from a context descriptor, and into the
per-packet TX struct.

Signed-off-by: Ed Swierk <eswierk@skyportsystems.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2017-12-22 09:53:23 +08:00
Dmitry Fleytman
6ee0e20b65 e1000e: Flush all receive queues on receive enable
Before this patch first netdev queue only was flushed.

Signed-off-by: Dmitry Fleytman <dmitry@daynix.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2016-09-27 17:54:22 +08:00
Dmitry Fleytman
6f3fbe4ed0 net: Introduce e1000e device emulation
This patch introduces emulation for the Intel 82574 adapter, AKA e1000e.

This implementation is derived from the e1000 emulation code, and
utilizes the TX/RX packet abstractions that were initially developed for
the vmxnet3 device. Although some parts of the introduced code may be
shared with e1000, the differences are substantial enough so that the
only shared resources for the two devices are the definitions in
hw/net/e1000_regs.h.

Similarly to vmxnet3, the new device uses virtio headers for task
offloads (for backends that support virtio extensions). Usage of
virtio headers may be forcibly disabled via a boolean device property
"vnet" (which is enabled by default). In such case task offloads
will be performed in software, in the same way it is done on
backends that do not support virtio headers.

The device code is split into two parts:

  1. hw/net/e1000e.c: QEMU-specific code for a network device;
  2. hw/net/e1000e_core.[hc]: Device emulation according to the spec.

The new device name is e1000e.

Intel specifications for the 82574 controller are available at:
http://www.intel.com/content/dam/doc/datasheet/82574l-gbe-controller-datasheet.pdf

Throughput measurement results (iperf2):

                Fedora 22 guest, TCP, RX
    4 ++------------------------------------------+
      |                                           |
      |                           X   X   X   X   X
  3.5 ++          X   X   X   X                   |
      |       X                                   |
      |                                           |
    3 ++                                          |
G     |   X                                       |
b     |                                           |
/ 2.5 ++                                          |
s     |                                           |
      |                                           |
    2 ++                                          |
      |                                           |
      |                                           |
  1.5 X+                                          |
      |                                           |
      +   +   +   +   +   +   +   +   +   +   +   +
    1 ++--+---+---+---+---+---+---+---+---+---+---+
     32  64  128 256 512  1   2   4   8  16  32  64
      B   B   B   B   B   KB  KB  KB  KB KB  KB  KB
                       Buffer size

               Fedora 22 guest, TCP, TX
  18 ++-------------------------------------------+
     |                        X                   |
  16 ++                           X   X   X   X   X
     |                   X                        |
  14 ++                                           |
     |                                            |
  12 ++                                           |
G    |               X                            |
b 10 ++                                           |
/    |                                            |
s  8 ++                                           |
     |                                            |
   6 ++          X                                |
     |                                            |
   4 ++                                           |
     |       X                                    |
   2 ++  X                                        |
     X   +   +   +   +   +    +   +   +   +   +   +
   0 ++--+---+---+---+---+----+---+---+---+---+---+
    32  64  128 256 512  1    2   4   8  16  32  64
     B   B   B   B   B   KB   KB  KB  KB KB  KB  KB
                       Buffer size

                Fedora 22 guest, UDP, RX
    3 ++------------------------------------------+
      |                                           X
      |                                           |
  2.5 ++                                          |
      |                                           |
      |                                           |
    2 ++                                 X        |
G     |                                           |
b     |                                           |
/ 1.5 ++                                          |
s     |                         X                 |
      |                                           |
    1 ++                                          |
      |                                           |
      |                 X                         |
  0.5 ++                                          |
      |        X                                  |
      X        +        +       +        +        +
    0 ++-------+--------+-------+--------+--------+
     32       64       128     256      512       1
      B        B         B       B        B      KB
                       Datagram size

                Fedora 22 guest, UDP, TX
    1 ++------------------------------------------+
      |                                           X
  0.9 ++                                          |
      |                                           |
  0.8 ++                                          |
  0.7 ++                                          |
      |                                           |
G 0.6 ++                                          |
b     |                                           |
/ 0.5 ++                                          |
s     |                                  X        |
  0.4 ++                                          |
      |                                           |
  0.3 ++                                          |
  0.2 ++                        X                 |
      |                                           |
  0.1 ++                X                         |
      X        X        +       +        +        +
    0 ++-------+--------+-------+--------+--------+
     32       64       128     256      512       1
      B        B         B       B        B      KB
                       Datagram size

              Windows 2012R2 guest, TCP, RX
  3.2 ++------------------------------------------+
      |                                   X       |
    3 ++                                          |
      |                                           |
  2.8 ++                                          |
      |                                           |
  2.6 ++                              X           |
G     |   X                   X   X           X   X
b 2.4 ++      X       X                           |
/     |                                           |
s 2.2 ++                                          |
      |                                           |
    2 ++                                          |
      |           X       X                       |
  1.8 ++                                          |
      |                                           |
  1.6 X+                                          |
      +   +   +   +   +   +   +   +   +   +   +   +
  1.4 ++--+---+---+---+---+---+---+---+---+---+---+
     32  64  128 256 512  1   2   4   8  16  32  64
      B   B   B   B   B   KB  KB  KB  KB KB  KB  KB
                       Buffer size

             Windows 2012R2 guest, TCP, TX
  14 ++-------------------------------------------+
     |                                            |
     |                                        X   X
  12 ++                                           |
     |                                            |
  10 ++                                           |
     |                                            |
G    |                                            |
b  8 ++                                           |
/    |                                    X       |
s  6 ++                                           |
     |                                            |
     |                                            |
   4 ++                               X           |
     |                                            |
   2 ++                                           |
     |           X   X            X               |
     +   X   X   +   +   X    X   +   +   +   +   +
   0 X+--+---+---+---+---+----+---+---+---+---+---+
    32  64  128 256 512  1    2   4   8  16  32  64
     B   B   B   B   B   KB   KB  KB  KB KB  KB  KB
                       Buffer size

              Windows 2012R2 guest, UDP, RX
  1.6 ++------------------------------------------X
      |                                           |
  1.4 ++                                          |
      |                                           |
  1.2 ++                                          |
      |                                  X        |
      |                                           |
G   1 ++                                          |
b     |                                           |
/ 0.8 ++                                          |
s     |                                           |
  0.6 ++                        X                 |
      |                                           |
  0.4 ++                                          |
      |                 X                         |
      |                                           |
  0.2 ++       X                                  |
      X        +        +       +        +        +
    0 ++-------+--------+-------+--------+--------+
     32       64       128     256      512       1
      B        B         B       B        B      KB
                       Datagram size

              Windows 2012R2 guest, UDP, TX
  0.6 ++------------------------------------------+
      |                                           X
      |                                           |
  0.5 ++                                          |
      |                                           |
      |                                           |
  0.4 ++                                          |
G     |                                           |
b     |                                           |
/ 0.3 ++                                 X        |
s     |                                           |
      |                                           |
  0.2 ++                                          |
      |                                           |
      |                         X                 |
  0.1 ++                                          |
      |                 X                         |
      X        X        +       +        +        +
    0 ++-------+--------+-------+--------+--------+
     32       64       128     256      512       1
      B        B         B       B        B      KB
                       Datagram size

Signed-off-by: Dmitry Fleytman <dmitry.fleytman@ravellosystems.com>
Signed-off-by: Leonid Bloch <leonid.bloch@ravellosystems.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2016-06-02 10:42:29 +08:00