[PATCH net-next v3 0/2] net: ipv4: allow directed broadcast routes to use dst hint

[Oscar Maes <oscmaes92@gmail.com>]

Currently, ip_extract_route_hint uses RTN_BROADCAST to decide
whether to use the route dst hint mechanism.

This check is too strict, as it prevents directed broadcast
routes from using the hint, resulting in poor performance
during bursts of directed broadcast traffic.

This series fixes this, and adds a new selftest to ensure
this does not regress.

Changes in v3:
 - Improved selftest
 - Use ipv4_is_zeronet to check daddr

Changes in v2:
 - Removed unused variable
 - Fixed formatting
 - Added new selftest

Link to v2: https://lore.kernel.org/netdev/20250814140309.3742-1-oscmaes92@gmail.com/

Oscar Maes (2):
  net: ipv4: allow directed broadcast routes to use dst hint
  selftests: net: add test for dst hint mechanism with directed
    broadcast addresses

 net/ipv4/ip_input.c                       | 11 ++--
 net/ipv4/route.c                          |  2 +-
 tools/testing/selftests/net/Makefile      |  1 +
 tools/testing/selftests/net/route_hint.sh | 79 +++++++++++++++++++++++
 4 files changed, 88 insertions(+), 5 deletions(-)
 create mode 100755 tools/testing/selftests/net/route_hint.sh

-- 
2.39.5