[portsyncd]: Store eth0 oper status into state DB (sonic-net#630)

portsyncd listens to the netlink messages. In order for SNMP
to get the current oper status of the managemnt interface,
portsyncd will store eth0 oper status explicitly into the
state database.

portsyncd/Makefile.am

@@ -1,4 +1,4 @@
-INCLUDES = -I $(top_srcdir) -I $(top_srcdir)/warmrestart
+INCLUDES = -I $(top_srcdir) -I $(top_srcdir)/warmrestart -I $(top_srcdir)/cfgmgr
 
 bin_PROGRAMS = portsyncd
 
@@ -8,7 +8,7 @@ else
 DBGFLAGS = -g
 endif
 
-portsyncd_SOURCES = portsyncd.cpp linksync.cpp $(top_srcdir)/warmrestart/warm_restart.cpp $(top_srcdir)/warmrestart/warm_restart.h
+portsyncd_SOURCES = portsyncd.cpp linksync.cpp $(top_srcdir)/warmrestart/warm_restart.cpp $(top_srcdir)/warmrestart/warm_restart.h $(top_srcdir)/cfgmgr/shellcmd.h
 
 portsyncd_CFLAGS = $(DBGFLAGS) $(AM_CFLAGS) $(CFLAGS_COMMON)
 portsyncd_CPPFLAGS = $(DBGFLAGS) $(AM_CFLAGS) $(CFLAGS_COMMON)

portsyncd/linksync.cpp

@@ -14,6 +14,7 @@
 #include "linkcache.h"
 #include "portsyncd/linksync.h"
 #include "warm_restart.h"
+#include "shellcmd.h"
 
 #include <iostream>
 #include <set>
@@ -24,6 +25,7 @@ using namespace swss;
 #define VLAN_DRV_NAME   "bridge"
 #define TEAM_DRV_NAME   "team"
 
+const string MGMT_PREFIX = "eth";
 const string INTFS_PREFIX = "Ethernet";
 const string LAG_PREFIX = "PortChannel";
 
@@ -40,8 +42,56 @@ extern "C" { extern struct if_nameindex *if_nameindex (void) __THROW; }
 LinkSync::LinkSync(DBConnector *appl_db, DBConnector *state_db) :
     m_portTableProducer(appl_db, APP_PORT_TABLE_NAME),
     m_portTable(appl_db, APP_PORT_TABLE_NAME),
-    m_statePortTable(state_db, STATE_PORT_TABLE_NAME)
+    m_statePortTable(state_db, STATE_PORT_TABLE_NAME),
+    m_stateMgmtPortTable(state_db, STATE_MGMT_PORT_TABLE_NAME)
 {
+    struct if_nameindex *if_ni, *idx_p;
+    if_ni = if_nameindex();
+
+    for (idx_p = if_ni;
+            idx_p != NULL && idx_p->if_index != 0 && idx_p->if_name != NULL;
+            idx_p++)
+    {
+        string key = idx_p->if_name;
+
+        /* Explicitly store management ports oper status into the state database.
+         * This piece of information is used by SNMP. */
+        if (!key.compare(0, MGMT_PREFIX.length(), MGMT_PREFIX))
+        {
+            string cmd, res;
+            cmd = "cat /sys/class/net/" + key + "/operstate";
+            try
+            {
+                EXEC_WITH_ERROR_THROW(cmd, res);
+            }
+            catch (...)
+            {
+                SWSS_LOG_WARN("Failed to get %s oper status", key.c_str());
+                continue;
+            }
+
+            /* Remove the trailing newline */
+            if (res.length() >= 1 && res.at(res.length() - 1) == '\n')
+            {
+                res.erase(res.length() - 1);
+                /* The value of operstate will be either up or down */
+                if (res != "up" && res != "down")
+                {
+                    SWSS_LOG_WARN("Unknown %s oper status %s",
+                            key.c_str(), res.c_str());
+                }
+                FieldValueTuple fv("oper_status", res);
+                vector<FieldValueTuple> fvs;
+                fvs.push_back(fv);
+
+                m_stateMgmtPortTable.set(key, fvs);
+                SWSS_LOG_INFO("Store %s oper status %s to state DB",
+                        key.c_str(), res.c_str());
+            }
+            continue;
+        }
+    }
+
     if (!WarmStart::isWarmStart())
     {
         /* See the comments for g_portSet in portsyncd.cpp */
@@ -61,25 +111,22 @@ LinkSync::LinkSync(DBConnector *appl_db, DBConnector *state_db) :
             }
         }
 
-        struct if_nameindex *if_ni, *idx_p;
-        if_ni = if_nameindex();
-        if (if_ni == NULL)
-        {
-            return;
-        }
-
-        for (idx_p = if_ni; ! (idx_p->if_index == 0 && idx_p->if_name == NULL); idx_p++)
+        for (idx_p = if_ni;
+                idx_p != NULL && idx_p->if_index != 0 && idx_p->if_name != NULL;
+                idx_p++)
         {
             string key = idx_p->if_name;
+
+            /* Skip all non-frontpanel ports */
             if (key.compare(0, INTFS_PREFIX.length(), INTFS_PREFIX))
             {
                 continue;
             }
 
             m_ifindexOldNameMap[idx_p->if_index] = key;
 
-            /* Bring down the existing kernel interfaces */
             string cmd, res;
+            /* Bring down the existing kernel interfaces */
             SWSS_LOG_INFO("Bring down old interface %s(%d)", key.c_str(), idx_p->if_index);
             cmd = "ip link set " + key + " down";
             try
@@ -106,7 +153,8 @@ void LinkSync::onMsg(int nlmsg_type, struct nl_object *obj)
     string key = rtnl_link_get_name(link);
 
     if (key.compare(0, INTFS_PREFIX.length(), INTFS_PREFIX) &&
-        key.compare(0, LAG_PREFIX.length(), LAG_PREFIX))
+        key.compare(0, LAG_PREFIX.length(), LAG_PREFIX) &&
+        key.compare(0, MGMT_PREFIX.length(), MGMT_PREFIX))
     {
         return;
     }
@@ -133,6 +181,17 @@ void LinkSync::onMsg(int nlmsg_type, struct nl_object *obj)
                        nlmsg_type, key.c_str(), admin, oper, addrStr, ifindex, master);
     }
 
+    if (!key.compare(0, MGMT_PREFIX.length(), MGMT_PREFIX))
+    {
+        FieldValueTuple fv("oper_status", oper ? "up" : "down");
+        vector<FieldValueTuple> fvs;
+        fvs.push_back(fv);
+        m_stateMgmtPortTable.set(key, fvs);
+        SWSS_LOG_INFO("Store %s oper status %s to state DB",
+                key.c_str(), oper ? "up" : "down");
+        return;
+    }
+
     /* teamd instances are dealt in teamsyncd */
     if (type && !strcmp(type, TEAM_DRV_NAME))
     {

portsyncd/linksync.h

@@ -20,7 +20,7 @@ class LinkSync : public NetMsg
 
 private:
     ProducerStateTable m_portTableProducer;
-    Table m_portTable, m_statePortTable;
+    Table m_portTable, m_statePortTable, m_stateMgmtPortTable;
 
     std::map<unsigned int, std::string> m_ifindexNameMap;
     std::map<unsigned int, std::string> m_ifindexOldNameMap;