ethernet: rps: T4928: adjust to Kernel ABI changes #2

Fix ValueError: Unknown format code 'x' for object of type 'str' added in
commit c0ffb8ba4e663 ("ethernet: rps: T4928: adjust to Kernel ABI changes").

2 files changed, 9 insertions, 5 deletions

diff --git a/python/vyos/ifconfig/ethernet.py b/python/vyos/ifconfig/ethernet.py
index b45d8ea28..5080144ff 100644
--- a/python/vyos/ifconfig/ethernet.py
+++ b/python/vyos/ifconfig/ethernet.py
@@ -239,7 +239,7 @@ class EthernetIf(Interface):
         if not isinstance(state, bool):
             raise ValueError('Value out of range')
 
-        rps_cpus = '0'
+        rps_cpus = 0
         queues = len(glob(f'/sys/class/net/{self.ifname}/queues/rx-*'))
         if state:
             # Enable RPS on all available CPUs except CPU0 which we will not
@@ -248,9 +248,13 @@ class EthernetIf(Interface):
             # representation of the CPUs which should participate on RPS, we
             # can enable more CPUs that are physically present on the system,
             # Linux will clip that internally!
-            rps_cpus = os.cpu_count()
-            if rps_cpus > 1:
-                rps_cpus -= 1
+            rps_cpus = (1 << os.cpu_count()) -1
+
+            # XXX: we should probably reserve one core when the system is under
+            # high preasure so we can still have a core left for housekeeping.
+            # This is done by masking out the lowst bit so CPU0 is spared from
+            # receive packet steering.
+            rps_cpus &= ~1
 
         for i in range(0, queues):
             self._write_sysfs(f'/sys/class/net/{self.ifname}/queues/rx-{i}/rps_cpus', f'{rps_cpus:x}')
diff --git a/smoketest/scripts/cli/test_interfaces_ethernet.py b/smoketest/scripts/cli/test_interfaces_ethernet.py
index ed611062a..e53413f0d 100755
--- a/smoketest/scripts/cli/test_interfaces_ethernet.py
+++ b/smoketest/scripts/cli/test_interfaces_ethernet.py
@@ -160,7 +160,7 @@ class EthernetInterfaceTest(BasicInterfaceTest.TestCase):
                 self.assertFalse(is_intf_addr_assigned(intf, addr['addr']))
 
     def test_offloading_rps(self):
-        # enable RPS on all available CPUs, RPS works woth a CPU bitmask,
+        # enable RPS on all available CPUs, RPS works with a CPU bitmask,
         # where each bit represents a CPU (core/thread). The formula below
         # expands to rps_cpus = 255 for a 8 core system
         rps_cpus = (1 << os.cpu_count()) -1