T7995: Add capability to start VPP dataplane during system deployment

debian/control

@@ -109,6 +109,7 @@ Depends:
   file,
   iproute2 (>= 6.0.0),
   linux-cpupower,
+  kexec-tools,
 # ipaddrcheck is widely used in IP value validators
   ipaddrcheck,
   ethtool (>= 6.10),

src/conf_mode/system_option.py

@@ -16,19 +16,22 @@
 
 import os
 import psutil
+import shlex
 
 from sys import exit
 from time import sleep
 
-
+from vyos.base import Warning
 from vyos.config import Config
 from vyos.configverify import verify_source_interface
 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.cpu import get_cpus
 from vyos.utils.dict import dict_search
 from vyos.utils.file import write_file
+from vyos.utils.file import read_file
 from vyos.utils.kernel import check_kmod
 from vyos.utils.process import cmd
 from vyos.utils.process import is_systemd_service_running
@@ -58,6 +61,28 @@
     'virtual-host': 'virtual-host',
 }
 
+# Managed keys
+MANAGED_SINGLE = {
+    'mitigations',
+    'intel_idle.max_cstate',
+    'processor.max_cstate',
+    'initcall_blacklist',
+    'amd_pstate',
+    'quiet',
+    'panic',
+    'hpet',
+    'mce',
+    'nosoftlockup',
+    'isolcpus',
+    'nohz_full',
+    'rcu_nocbs',
+    'nmi_watchdog',
+    'numa_balancing',
+    'default_hugepagesz',
+}
+
+MANAGED_HUGEPAGES = {'hugepagesz', 'hugepages'}
+
 
 def _get_total_hugepages_and_memory(config):
     unit_map = {'M': 1 << 20, 'G': 1 << 30}
@@ -112,10 +137,10 @@ def verify(options):
         if 'source_address' in config:
             address = config['source_address']
             if not is_addr_assigned(config['source_address']):
-                raise ConfigError('No interface with address "{address}" configured!')
+                raise ConfigError(f'No interface with address "{address}" configured!')
 
         if 'source_interface' in config:
-            # verify_source_interface reuires key 'ifname'
+            # verify_source_interface requires key 'ifname'
             config['ifname'] = config['source_interface']
             verify_source_interface(config)
             if 'source_address' in config:
@@ -244,10 +269,128 @@ def generate(options):
 
     grub_util.update_kernel_cmdline_options(' '.join(cmdline_options))
 
+    options['cmdline_options'] = cmdline_options
+
     return None
 
 
+def generate_cmdline_for_kexec(options):
+    """
+    Build an updated kernel cmdline string based on desired options and the
+    currently running /proc/cmdline.
+
+    Returns:
+        (kexec_required: bool, new_cmdline: str)
+        - kexec_required is True if kernel options were added, removed,
+          or modified.
+    """
+
+    def parse_token(tok):
+        return tok.split('=', 1) if '=' in tok else [tok, None]
+
+    # Read current cmdline
+    raw_cmdline = read_file('/proc/cmdline').strip()
+    tokens = shlex.split(raw_cmdline)
+
+    # Separate normal keys vs hugepages
+    current_single_opts = {}
+    hugepages_current = []
+
+    # Split existing cmdline into normal keys and hugepages pairs
+    i = 0
+    while i < len(tokens):
+        key, val = parse_token(tokens[i])
+        if key == 'hugepagesz':
+            size = val
+            count = None
+            if i + 1 < len(tokens):
+                nk, nv = parse_token(tokens[i + 1])
+                if nk == 'hugepages':
+                    count = nv
+                    i += 1
+            hugepages_current.append([size, count])
+        else:
+            current_single_opts[key] = val
+        i += 1
+
+    kexec_required = False
+
+    # Extract desired single-value options from options['cmdline_options']
+    desired_single_opts = {}
+    for entry in options.get("cmdline_options", []):
+        for tok in entry.split():
+            k, v = parse_token(tok)
+            if k not in MANAGED_HUGEPAGES:
+                desired_single_opts[k] = v
+
+    # Remove obsolete managed options
+    for k in list(current_single_opts.keys()):
+        if k in MANAGED_SINGLE and k not in desired_single_opts:
+            kexec_required = True
+            current_single_opts.pop(k)
+
+    # Add/update managed single-value options
+    for k, v in desired_single_opts.items():
+        if current_single_opts.get(k, '') != v:
+            kexec_required = True
+            current_single_opts[k] = v
+
+    # Build desired hugepages dictionary
+    hp_cfg = options.get('kernel', {}).get('memory', {}).get('hugepage_size', {})
+    desired_hp = {size: cfg.get('hugepage_count') for size, cfg in hp_cfg.items()}
+
+    new_hugepages = []
+    seen_sizes = set()
+
+    # Update existing hugepages_pairs and remove obsolete
+    for size, count in hugepages_current:
+        if size in desired_hp:
+            if count != desired_hp[size]:
+                kexec_required = True
+                count = desired_hp[size]
+            new_hugepages.append([size, count])
+            seen_sizes.add(size)
+        else:
+            # obsolete hugepages -> remove
+            kexec_required = True
+
+    # Add new hugepages that do not exist in current cmdline
+    for size, count in desired_hp.items():
+        if size not in seen_sizes:
+            new_hugepages.append([size, count])
+            kexec_required = True
+
+    # Reconstruct final cmdline
+    new_tokens = []
+    for key, value in current_single_opts.items():
+        new_tokens.append(f'{key}={value}' if value is not None else key)
+
+    # Append hugepages pairs
+    for size, count in new_hugepages:
+        new_tokens.append(f'hugepagesz={size}')
+        if count is not None:
+            new_tokens.append(f'hugepages={count}')
+
+    cmdline_new = ' '.join(new_tokens)
+
+    return kexec_required, cmdline_new
+
+
 def apply(options):
+    kexec_required, cmdline_new = generate_cmdline_for_kexec(options)
+    if kexec_required:
+        if not boot_configuration_complete() and os.environ.get('VYOS_CONFIGD'):
+            cmd(
+                f'sudo kexec -l /boot/vmlinuz --initrd=/boot/initrd.img --command-line="{cmdline_new}"'
+            )
+            os.sync()
+            cmd('sudo systemctl kexec')
+        elif boot_configuration_complete():
+            Warning(
+                'Kernel configuration options have changed. '
+                'To apply these changes, you must save the configuration and reboot the system!'
+            )
+
     # System bootup beep
     beep_service = 'vyos-beep.service'
     if 'startup_beep' in options: