selftests: mlxsw: tc_flower_scale: Add a traffic test

Add a test that checks that the created filters do actually trigger on
matching traffic.

Exercising all the rules would be a very lengthy process. Instead, take a
log2 subset of rules. The logic behind picking log2 rules is that then
every bit of the instantiated item's number is exercised. This should catch
issues whether they happen at the high end, low end, or somewhere in
between.

Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Amit Cohen <amcohen@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: mlxsw: Remove a redundant if statement in tc_flower_scale test

Currently, the error return code of the failure condition is lost after
using an if statement, so the test doesn't fail when it should.

Remove the if statement that separates the condition and the error code
check, so the test won't always pass.

Fixes: abfce9e062021 ("selftests: mlxsw: Reduce running time using offload indication")
Reported-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Danielle Ratson <danieller@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: mlxsw: Reduce running time using offload indication

After adding a given number of flower rules for different IPv6
addresses, the test generates traffic and ensures that each packet is
received, which is time-consuming.

Instead, test the offload indication of the tc flower rules and reduce
the running time by half.

Signed-off-by: Danielle Ratson <danieller@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: mlxsw: Add tc flower scale test

Add test of capacity to offload flower.

This is a generic portion of the test that is meant to be called from a
driver that supplies a particular number of rules to be tested with.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Reviewed-by: Yuval Mintz <yuvalm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>