Mtce: increase hbsAgent/hwmond command RX socket buffer

hbsAgent and hwmond obtain host inventory from the mtcAgent.

After a process restart they emit a "ready" event, which triggers
mtcAgent to send it all node inventory as individula messages for each
host, sometimes 2.

On large deployments (100+ nodes) this burst of messaging can overrun
the current command receive socket buffer, causing dropped inventory
messages that can lead to incomplete monitoring coverage.

This change raises the command channel's SO_RCVBUF for both hbsAgent
and hwmond to rmem size to provide headroom for these restart bursts.

Risk Assessment:

- No protocol change; process form and function remains unchanged.
- Safe for upgrade/rollback with no API change, only local socket
  sizing is altered.
- Memory impact is limited to the larger RX buffer allowable
  per process.

Test Plan: The issue has been verified to occur with both hwmond and
           the hbsAgent processes without this update and then fixed
           with this update.

PASS: Verify socket memory is increased to kernel rmem value for both
      hbsAgent and hwmond
PASS: Verify in an at-scale 100 node system, running WRCP, WRO and WRA
      app stack, on the active controller that a ...
PASS: - hwmond process restart gets required inventory for all node
PASS: - hbsAgent process restart gets required inventory for all nodes
PASS: Verify restart of hbsAgent on the standby controller gets the
      required inventory for all nodes.
PASS: Verify restart of each condition above 5 times

Closes-Bug: 2125017
Change-Id: I6b77e0737af7313fba199afc6b9721c7ef48e2c0
Signed-off-by: Eric MacDonald <eric.macdonald@windriver.com>

mtce/src/heartbeat/hbsAgent.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013-2020 Wind River Systems, Inc.
+ * Copyright (c) 2013-2020, 2025 Wind River Systems, Inc.
 *
 * SPDX-License-Identifier: Apache-2.0
 *
@@ -774,6 +774,7 @@ int hbs_socket_init ( void )
     {
         /* load local variables */
         int port = hbs_config.mtc_to_hbs_cmd_port ;
+        int rmem_max = daemon_get_rmem_max();
 
         /* Handle re-init case */
         if ( hbs_sock.mtc_to_hbs_sock != NULL )
@@ -788,6 +789,17 @@ int hbs_socket_init ( void )
                          port,
                          IPPROTO_UDP);
 
+        /* Set rx socket buffer size to rmem_max.
+         * Needed to handle inventory push from mtcAgent over
+         * process restart on at-scale system deployments. */
+        if (rmem_max > 0)
+        {
+            hbs_sock.mtc_to_hbs_sock->setSocketMemory(
+                hbs_config.mgmnt_iface,
+                "mtc command rx socket memory",
+                rmem_max );
+        }
+
         /* Check the socket */
         if (hbs_sock.mtc_to_hbs_sock != NULL )
         {

mtce/src/hwmon/hwmonMsg.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013, 2016 Wind River Systems, Inc.
+ * Copyright (c) 2013, 2016, 2025 Wind River Systems, Inc.
 *
 * SPDX-License-Identifier: Apache-2.0
 *
@@ -70,6 +70,7 @@ void hwmon_msg_fini ( void )
 int cmd_rx_port_init ( int port )
 {
     int rc = PASS ;
+    int rmem_max = daemon_get_rmem_max();
     hwmon_sock.cmd_port = port ;
 
     mtcAgent_ip = getipbyname ( CONTROLLER );
@@ -82,6 +83,16 @@ int cmd_rx_port_init ( int port )
         return (rc);
     }
 
+    /* Set rx socket buffer size to rmem_max.
+     * Needed to handle inventory push from mtcAgent over
+     * process restart on at-scale system deployments. */
+    if (rmem_max > 0)
+    {
+        hwmon_sock.cmd_sock->setSocketMemory(
+            daemon_get_cfg_ptr()->mgmnt_iface,
+            "mtc command rx socket memory",
+            rmem_max );
+    }
     return (rc);
 }