Add explicit lossy check and update UT

Signed-off-by: Jianyue Wu <jianyuew@nvidia.com>

Author: jianyuewu

cfgmgr/buffermgrdyn.cpp

@@ -944,10 +944,10 @@ void BufferMgrDynamic::updateBufferObjectListToDb(const string &key, const strin
 // We have to check the headroom ahead of applying them
 task_process_status BufferMgrDynamic::allocateProfile(const string &speed, const string &cable_len, const string &mtu, const string &threshold, const string &gearbox_model, long lane_count, string &profile_name)
 {
-    bool is_lossless = (profile_name.find("pg_lossless_") != string::npos);
+    bool is_lossless = (profile_name.find("lossless") != string::npos);
     if (cable_len == "0m" && is_lossless)
     {
-        SWSS_LOG_NOTICE("Not creating PG profile when cable length is set to %s", cable_len.c_str());
+        SWSS_LOG_NOTICE("Not creating lossless profile when cable length is set to %s", cable_len.c_str());
         return task_process_status::task_success;
     }
 
@@ -1469,9 +1469,16 @@ task_process_status BufferMgrDynamic::refreshPgsForPort(const string &port, cons
                 continue;
             }
 
-            if (cable_length == "0m" && it->second.lossless)
+            // If cable len is 0m, remove lossless PG, keep lossy PG.
+            bool old_profile_is_lossless = (oldProfile.find("lossless") != string::npos);
+            if (cable_length == "0m" && portPg.lossless && old_profile_is_lossless)
             {
-                updateBufferObjectToDb(key, oldProfile, false); // 0m, remove PG.
+                if (oldProfile.empty())
+                {
+                    SWSS_LOG_WARN("No lossless profile found for port %s when cable length is set to '0m'.", port.c_str());
+                    continue;
+                }
+                updateBufferObjectToDb(key, oldProfile, false);
                 SWSS_LOG_NOTICE("All profiles for port %s have been removed due to cable length being set to '0m'", port.c_str());
 
                 if (!oldProfile.empty())

tests/mock_tests/buffermgrdyn_ut.cpp

@@ -1477,15 +1477,30 @@ namespace buffermgrdyn_test
         ASSERT_EQ(m_dynamicBuffer->m_portInfoLookup["Ethernet12"].state, PORT_READY);
     }
 
+    /*
+    Purpose: To verify the behavior of the buffer mgr dynamic when the cable length is set to "0m".
+    Here set to 0m indicates no lossless profile will be created, can still create lossy profile.
+    Steps:
+    1. Initialize the environment, including default lossless parameters and MMU size.
+    2. Start the Buffer Manager and initialize the port.
+    3. No new lossless profile is created when the cable length is "0m".
+    4. Existing lossless profiles are removed when the cable length is "0m".
+    5. No new lossless PG is created when the cable length is "0m".
+    6. When the cable length is updated to "5m", the correct lossless profiles and PGs are created.
+    7. When the cable length is updated back to "0m", the lossless profiles and PGs are removed.
+    8. Check if port MTU update, PG and profile still there.
+    9. When the cable length is "0m", lossy PGs remain, while lossless PGs are deleted.
+    */
     TEST_F(BufferMgrDynTest, SkipProfileCreationForZeroCableLength)
     {
         vector<FieldValueTuple> fieldValues;
         vector<string> keys;
 
-        // Prepare information that will be read at the beginning
+        // 1. Initialize the environment, including default lossless parameters and MMU size.
         InitDefaultLosslessParameter();
         InitMmuSize();
 
+        // 2. Start the Buffer Manager and initialize the port.
         StartBufferManager();
 
         InitPort();
@@ -1506,56 +1521,95 @@ namespace buffermgrdyn_test
         appBufferProfileTable.getKeys(keys);
         ASSERT_EQ(keys.size(), 4);
         ASSERT_EQ(m_dynamicBuffer->m_bufferProfileLookup.size(), 4);
-
-        // 1. Set cable length to "0m"
-        InitCableLength("Ethernet0", "0m");
+        InitCableLength("Ethernet0", "5m");
         ASSERT_EQ(m_dynamicBuffer->m_portInfoLookup["Ethernet0"].state, PORT_READY);
+
+        auto expectedProfile = "pg_lossless_100000_5m_profile";
+        CheckPg("Ethernet0", "Ethernet0:3-4", expectedProfile);
+
+        // 3. No new lossless profile is created when the cable length is "0m".
+        cableLengthTable.set("AZURE",
+                            {
+                            {"Ethernet0", "0m"}
+                            });
+        HandleTable(cableLengthTable);
         // Expect profile not created
         auto zeroMProfile = "pg_lossless_100000_0m_profile";
         ASSERT_EQ(m_dynamicBuffer->m_bufferProfileLookup.find(zeroMProfile), m_dynamicBuffer->m_bufferProfileLookup.end());
 
-        // 2. Check if the reference for 5m profile of this port had been deleted in buffer PG table
+        // 4. Existing lossless profiles are removed when the cable length is "0m".
         // Since the cable length is set to 0m, previous profile for 5m should not exist.
         ASSERT_TRUE(m_dynamicBuffer->m_bufferProfileLookup.find("pg_lossless_100000_5m_profile") == m_dynamicBuffer->m_bufferProfileLookup.end());
 
-        // 3. Add a PG, Ethernet0:6, it should not be created with 0m profile
+        // 5. No new lossless PG is created when the cable length is "0m".
         // The expectation is that no new PGs should be created with a cable length of 0m.
         InitBufferPg("Ethernet0|6");
         ASSERT_TRUE(m_dynamicBuffer->m_portPgLookup.find("Ethernet0:6") == m_dynamicBuffer->m_portPgLookup.end());
 
-        // 4. Update cable length to 5m, then Ethernet0:6 and Ethernet0:3-4 should be created with 5m profile
-        InitCableLength("Ethernet0", "5m");
+        // 6. When the cable length is updated to "5m", the correct lossless profiles and PGs are created.
+        cableLengthTable.set("AZURE",
+                            {
+                            {"Ethernet0", "5m"}
+                            });
+        HandleTable(cableLengthTable);
         // Check if the profiles are created correctly
         CheckPg("Ethernet0", "Ethernet0:3-4", "pg_lossless_100000_5m_profile");
         CheckPg("Ethernet0", "Ethernet0:6", "pg_lossless_100000_5m_profile");
 
-        // 5. Update cable length to 0m, then Ethernet0:6 should be deleted, Ethernet0:3-4 should be deleted and 0m profile also not exist, and 5m profile should be deleted, PG also deleted, as profiles not exist
-        InitCableLength("Ethernet0", "0m");
-        static_cast<Orch *>(m_dynamicBuffer)->doTask();
-        // Check that the profiles for 0m and 5m both do not exist
+        // 7. When the cable length is updated back to "0m", the lossless profiles and PGs are removed.
+        cableLengthTable.set("AZURE",
+                            {
+                            {"Ethernet0", "0m"}
+                            });
+        HandleTable(cableLengthTable);
+        // Check that the profiles for 0m do not exist, 5m profile could be still there, because it is shared by other ports
         ASSERT_TRUE(m_dynamicBuffer->m_bufferProfileLookup.find("pg_lossless_100000_0m_profile") == m_dynamicBuffer->m_bufferProfileLookup.end());
         ASSERT_TRUE(m_dynamicBuffer->m_bufferProfileLookup.find("pg_lossless_100000_5m_profile") == m_dynamicBuffer->m_bufferProfileLookup.end());
         // Check that the PGs for Ethernet0:3-4 and Ethernet0:6 have been deleted
         ASSERT_TRUE(m_dynamicBuffer->m_portPgLookup.find("Ethernet0:3-4") == m_dynamicBuffer->m_portPgLookup.end());
         ASSERT_TRUE(m_dynamicBuffer->m_portPgLookup.find("Ethernet0:6") == m_dynamicBuffer->m_portPgLookup.end());
 
-        // 6. Check if port MTU update, PG and profile still there
-        InitCableLength("Ethernet0", "5m");
+        // 8. Check if port MTU update, PG and profile still there.
+        cableLengthTable.set("AZURE",
+                            {
+                            {"Ethernet0", "5m"}
+                            });
+        HandleTable(cableLengthTable);
         string mtu = "4096";
-        m_dynamicBuffer->m_portInfoLookup["Ethernet0"].mtu = mtu;
-        static_cast<Orch *>(m_dynamicBuffer)->doTask();
+        m_dynamicBuffer->m_portInfoLookup["Ethernet0"].mtu = mtu; 
         // Check if the profile is created correctly
         CheckPg("Ethernet0", "Ethernet0:3-4", "pg_lossless_100000_5m_profile");
         CheckPg("Ethernet0", "Ethernet0:6", "pg_lossless_100000_5m_profile");
 
         // 7. Check if lossy PG can still be created
         InitBufferPg("Ethernet0|0", "ingress_lossy_profile");
-        InitCableLength("Ethernet0", "0m");
+        cableLengthTable.set("AZURE",
+                            {
+                            {"Ethernet0", "0m"}
+                            });
+        HandleTable(cableLengthTable);
         bool found = false;
         auto it = m_dynamicBuffer->m_portPgLookup.find("Ethernet0");
         if (it != m_dynamicBuffer->m_portPgLookup.end()) {
             found = (it->second.find("Ethernet0:0") != it->second.end());
         }
         ASSERT_TRUE(found);
+
+        // 9. When the cable length is "0m", lossy PGs remain, while lossless PGs are deleted.
+        cableLengthTable.set("AZURE",
+                            {
+                            {"Ethernet0", "0m"}
+                            });
+        HandleTable(cableLengthTable);
+        it = m_dynamicBuffer->m_portPgLookup.find("Ethernet0");
+        if (it != m_dynamicBuffer->m_portPgLookup.end()) {
+            found = (it->second.find("Ethernet0:0") != it->second.end());
+        }
+        ASSERT_TRUE(found);
+        ASSERT_TRUE(m_dynamicBuffer->m_bufferProfileLookup.find("pg_lossless_100000_0m_profile") == m_dynamicBuffer->m_bufferProfileLookup.end());
+        ASSERT_TRUE(m_dynamicBuffer->m_bufferProfileLookup.find("pg_lossless_100000_5m_profile") == m_dynamicBuffer->m_bufferProfileLookup.end());
+        // Check that the PGs for Ethernet0:3-4 and Ethernet0:6 have been deleted
+        ASSERT_TRUE(m_dynamicBuffer->m_portPgLookup.find("Ethernet0:3-4") == m_dynamicBuffer->m_portPgLookup.end());
+        ASSERT_TRUE(m_dynamicBuffer->m_portPgLookup.find("Ethernet0:6") == m_dynamicBuffer->m_portPgLookup.end());
     }
 }