[PATCH net-next v2 0/3] net: introduce rps_default_mask

[Paolo Abeni <pabeni@redhat.com>]

Real-time setups try hard to ensure proper isolation between time
critical applications and e.g. network processing performed by the
network stack in softirq and RPS is used to move the softirq 
activity away from the isolated core.

If the network configuration is dynamic, with netns and devices
routinely created at run-time, enforcing the correct RPS setting
on each newly created device allowing to transient bad configuration
became complex.

These series try to address the above, introducing a new
sysctl knob: rps_default_mask. The new sysctl entry allows
configuring a systemwide RPS mask, to be enforced since receive 
queue creation time without any fourther per device configuration
required.

Additionally, a simple self-test is introduced to check the 
rps_default_mask behavior.

v1 -> v2:
 - fix sparse warning in patch 2/3

Paolo Abeni (3):
  net/sysctl: factor-out netdev_rx_queue_set_rps_mask() helper
  net/core: introduce default_rps_mask netns attribute
  self-tests: introduce self-tests for RPS default mask

 Documentation/admin-guide/sysctl/net.rst      |  6 ++
 include/linux/netdevice.h                     |  1 +
 net/core/net-sysfs.c                          | 73 +++++++++++--------
 net/core/sysctl_net_core.c                    | 58 +++++++++++++++
 tools/testing/selftests/net/Makefile          |  1 +
 tools/testing/selftests/net/config            |  3 +
 .../testing/selftests/net/rps_default_mask.sh | 57 +++++++++++++++
 7 files changed, 169 insertions(+), 30 deletions(-)
 create mode 100755 tools/testing/selftests/net/rps_default_mask.sh

-- 
2.26.2