vpp: T8460: Use isolated cpus for VPP cpu-cores

VPP CPU core assignment now uses kernel-isolated CPUs (from /sys/devices/system/cpu/isolated) with explicit corelist-workers instead of computing offsets from available cores with skip-cores/workers. Added validation that enough CPUs are actually isolated before VPP starts, and that isolate-cpus config only references existing CPU IDs. Moved smoketest for kernel option 'isolate-cpus' to test_vpp.py

1 files changed, 27 insertions, 0 deletions

diff --git a/src/conf_mode/system_option.py b/src/conf_mode/system_option.py
index 41b9a23bb..b7487de8a 100755
--- a/src/conf_mode/system_option.py
+++ b/src/conf_mode/system_option.py
@@ -28,7 +28,10 @@ from vyos.configverify import verify_interface_exists
 from vyos.system import grub_util
 from vyos.template import render
 from vyos.utils.boot import boot_configuration_complete
+from vyos.utils.convert import range_str_to_list
+from vyos.utils.convert import list_to_range_str
 from vyos.utils.cpu import get_cpus
+from vyos.utils.cpu import get_available_cpus
 from vyos.utils.dict import dict_search
 from vyos.utils.file import write_file
 from vyos.utils.file import read_file
@@ -44,6 +47,7 @@ from vyos import ConfigError
 from vyos import airbag
 
 from vyos.vpp.config_resource_checks import memory as mem_check
+from vyos.vpp.config_resource_checks.resource_defaults import default_resource_map
 
 airbag.enable()
 
@@ -239,6 +243,29 @@ def verify(options):
                 f'AMD pstate driver cannot be used with "{cpu_vendor}" CPU!'
             )
 
+        isolate_cpus = dict_search('kernel.cpu.isolate_cpus', options)
+        if isolate_cpus:
+            available_cores = sorted({int(cpu['cpu']) for cpu in get_available_cpus()})
+            cpus_list = range_str_to_list(isolate_cpus)
+            reserved_cpus = default_resource_map.get('reserved_cpu_cores')
+
+            cpus_available = len(available_cores) - reserved_cpus
+            if len(cpus_list) > cpus_available:
+                raise ConfigError(
+                    f'Cannot isolate {len(cpus_list)} CPUs ({isolate_cpus}): '
+                    f'only {cpus_available} of {len(available_cores)} physical cores '
+                    f'are available ({reserved_cpus} reserved for the system)'
+                )
+
+            not_available = [cpu for cpu in cpus_list if cpu not in available_cores]
+            if not_available:
+                not_available_str = list_to_range_str(not_available)
+                available_str = list_to_range_str(available_cores)
+                raise ConfigError(
+                    f'CPU(s) {not_available_str} do not exist on this system. '
+                    f'Available CPUs: {available_str}'
+                )
+
         _, hp_memory_bytes = _get_total_hugepages_and_memory(
             options['kernel'].get('memory', {})
         )