Test PACKET_FANOUT_EBPF by inserting a program into the the kernel
with bpf(), then attaching it to the fanout group. Observe the same
payload-based distribution as in the PACKET_FANOUT_CBPF test.
Signed-off-by: NWillem de Bruijn <willemb@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Test PACKET_FANOUT_CBPF by inserting a cBPF program that selects a
socket by payload. Requires modifying the test program to send
packets with multiple payloads.

Also fix a bug in testing the return value of mmap()
Signed-off-by: NWillem de Bruijn <willemb@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

psock_fanout tests the various fanout modes. Change the test for
rollover mode to expect early rollover due to socket pressure
as implemented in 2ccdbaa6 ("packet: rollover lock contention
avoidance").
Signed-off-by: NWillem de Bruijn <willemb@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The while loop in sock_fanout_read_ring() checks mmap region
bounds after access, causing it to segfault. Fix it to check
count before accessing header->tp_status. This problem can be
reproduced consistently when the test in run as follows:

    make -C tools/testing/selftests TARGETS=net run_tests
    or
    make run_tests from tools/testing/selftests
    or
    make run_test from tools/testing/selftests/net
Signed-off-by: NShuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds a simple test case that probes the packet socket's
TPACKET_V1, TPACKET_V2 and TPACKET_V3 behavior regarding mmap(2)'ed
I/O for a small burst of 100 packets. The test currently runs for ...

  TPACKET_V1: RX_RING, TX_RING
  TPACKET_V2: RX_RING, TX_RING
  TPACKET_V3: RX_RING

... and will output on success:

  test: TPACKET_V1 with PACKET_RX_RING .................... 100 pkts (9600 bytes)
  test: TPACKET_V1 with PACKET_TX_RING .................... 100 pkts (9600 bytes)
  test: TPACKET_V2 with PACKET_RX_RING .................... 100 pkts (9600 bytes)
  test: TPACKET_V2 with PACKET_TX_RING .................... 100 pkts (9600 bytes)
  test: TPACKET_V3 with PACKET_RX_RING .................... 100 pkts (9600 bytes)
  OK. All tests passed

Reusable parts of psock_fanout.c have been put into a psock_lib.h
file for common usage. Test case successfully tested on x86_64.
Signed-off-by: NDaniel Borkmann <dborkman@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The packetsocket fanout test uses a packet ring. Use TPACKET_V2
instead of TPACKET_V1 to work around a known 32/64 bit issue in
the older ring that manifests on sparc64.
Signed-off-by: NWillem de Bruijn <willemb@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Suggested-by: NDaniel Baluta <daniel.baluta@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NDaniel Baluta <dbaluta@ixiacom.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix flaky results with PACKET_FANOUT_HASH depending on whether the
two flows hash into the same packet socket or not.

Also adds tests for PACKET_FANOUT_LB and PACKET_FANOUT_CPU and
replaces the counting method with a packet ring.
Signed-off-by: NWillem de Bruijn <willemb@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Reported-by: NDaniel Baluta <dbaluta@ixiacom.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Changes:
  v3->v2: rebase (no other changes)
          passes selftest
  v2->v1: read f->num_members only once
          fix bug: test rollover mode + flag

Minimize packet drop in a fanout group. If one socket is full,
roll over packets to another from the group. Maintain flow
affinity during normal load using an rxhash fanout policy, while
dispersing unexpected traffic storms that hit a single cpu, such
as spoofed-source DoS flows. Rollover breaks affinity for flows
arriving at saturated sockets during those conditions.

The patch adds a fanout policy ROLLOVER that rotates between sockets,
filling each socket before moving to the next. It also adds a fanout
flag ROLLOVER. If passed along with any other fanout policy, the
primary policy is applied until the chosen socket is full. Then,
rollover selects another socket, to delay packet drop until the
entire system is saturated.

Probing sockets is not free. Selecting the last used socket, as
rollover does, is a greedy approach that maximizes chance of
success, at the cost of extreme load imbalance. In practice, with
sufficiently long queues to absorb bursts, sockets are drained in
parallel and load balance looks uniform in `top`.

To avoid contention, scales counters with number of sockets and
accesses them lockfree. Values are bounds checked to ensure
correctness.

Tested using an application with 9 threads pinned to CPUs, one socket
per thread and sufficient busywork per packet operation to limits each
thread to handling 32 Kpps. When sent 500 Kpps single UDP stream
packets, a FANOUT_CPU setup processes 32 Kpps in total without this
patch, 270 Kpps with the patch. Tested with read() and with a packet
ring (V1).

Also, passes psock_fanout.c unit test added to selftests.
Signed-off-by: NWillem de Bruijn <willemb@google.com>
Reviewed-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>