[LLDP] Enhance lldmgrd Redis events handling (#10593)

Why I did it
When lldpmgrd handled events of other tables besides PORT_TABLE, error message was printed to log.

How I did it
Handle event according to its file descriptor instead of looping all registered selectables for each coming event.

How to verify it
I verified same events are being handled by printing events key and operation, before and after the change.
Also, before the change, in init flow after config reload, when lldpmgrd handled events of other tables besides PORT_TABLE, error messages were printed to log, this issue is solved now.

dockers/docker-lldp/lldpmgrd

@@ -76,6 +76,9 @@ class LldpManager(daemon_base.DaemonBase):
  self.app_port_table = swsscommon.Table(self.appl_db, swsscommon.APP_PORT_TABLE_NAME)
  self.state_port_table = swsscommon.Table(self.state_db, swsscommon.STATE_PORT_TABLE_NAME)
 
+ self.port_config_done = False
+ self.port_init_done = False
+
  def update_hostname(self, hostname):
  cmd = "lldpcli configure system hostname {0}".format(hostname)
  self.log_debug("Running command: '{}'".format(cmd))
@@ -247,6 +250,23 @@ class LldpManager(daemon_base.DaemonBase):
  self.log_info("Hostname changed old {0}, new {1}".format(self.hostname, hostname))
  self.update_hostname(hostname)
 
+ def lldp_process_port_table_event(self, key, op, fvp):
+ if (key != "PortInitDone") and (key != "PortConfigDone"):
+ if op == "SET":
+ if fvp:
+ if "up" in dict(fvp).get("oper_status",""):
+ self.generate_pending_lldp_config_cmd_for_port(key, dict(fvp))
+ else:
+ self.pending_cmds.pop(key, None)
+ elif op == "DEL":
+ self.pending_cmds.pop(key, None)
+ else:
+ self.log_error("unknown operation '{}'".format(op))
+ elif key == "PortInitDone":
+ self.port_init_done = True
+ elif key == "PortConfigDone":
+ self.port_config_done = True
+
  def run(self):
  """
  Subscribes to notifications of changes in the PORT table
@@ -267,8 +287,6 @@ class LldpManager(daemon_base.DaemonBase):
 
  # Daemon is paused on the configuration file to avoid lldp packets with wrong information
  # until all interfaces are well configured on lldpd
- port_init_done = False
- port_config_done = False
  resume_lldp_sent = False
  start_time = time.time()
 
@@ -288,44 +306,30 @@ class LldpManager(daemon_base.DaemonBase):
 
  # Listen for changes to the PORT table in the CONFIG_DB and APP_DB
  while True:
- (state, c) = sel.select(SELECT_TIMEOUT_MS)
+ (state, selectableObj) = sel.select(SELECT_TIMEOUT_MS)
 
  if state == swsscommon.Select.OBJECT:
- (key, op, fvp) = sst_mgmt_ip_confdb.pop()
- if key:
+ if selectableObj.getFd() == sst_mgmt_ip_confdb.getFd():
+  (key, op, fvp) = sst_mgmt_ip_confdb.pop()
  self.lldp_process_mgmt_info_change(op, dict(fvp), key)
-
- (key, op, fvp) = sst_device_confdb.pop()
- if key:
+ elif selectableObj.getFd() == sst_device_confdb.getFd():
+ (key, op, fvp) = sst_device_confdb.pop()
  self.lldp_process_device_table_event(op, dict(fvp), key)
-
- (key, op, fvp) = sst_appdb.pop()
- if (key != "PortInitDone") and (key != "PortConfigDone"):
- if op == "SET":
- if fvp:
- if "up" in dict(fvp).get("oper_status",""):
- self.generate_pending_lldp_config_cmd_for_port(key, dict(fvp))
- else:
- self.pending_cmds.pop(key, None)
- elif op == "DEL":
- self.pending_cmds.pop(key, None)
- else:
- self.log_error("unknown operation")
-
- elif key == "PortInitDone":
- port_init_done = True
- elif key == "PortConfigDone":
- port_config_done = True
+ elif selectableObj.getFd() == sst_appdb.getFd():
+ (key, op, fvp) = sst_appdb.pop()
+ self.lldp_process_port_table_event(key, op, fvp)
+ else:
+ self.log_error("Got unexpected selectable object")
 
  # Process all pending commands
  self.process_pending_cmds()
 
  # Resume the daemon since all interfaces data updated and configured to the lldpd so no miss leading packets will be sent
  if not resume_lldp_sent:
  if check_timeout(self, start_time):
- port_init_done = port_config_done = True
- if port_init_done and port_config_done:
- port_init_done = port_config_done = False
+ self.port_init_done = self.port_config_done = True
+ if self.port_init_done and self.port_config_done:
+ self.port_init_done = self.port_config_done = False
  rc, stderr = run_cmd(self, "lldpcli resume")
  if rc != 0:
  self.log_error("Failed to resume lldpd with command: 'lldpcli resume': {}".format(stderr))