[PFC_WD] Avoid applying ZeroBuffer Profiles to ingress PG when a PFC storm is detected (sonic-net#2304)

What I did
Avoid dropping traffic that is ingressing the port/pg that is in storm. The code changes in this PR avoid creating the ingress zero pool and profile and does not attach any zero profile to the ingress pg when pfcwd is triggered

Revert changes related to sonic-net#1480 where the retry mechanism was added to BufferOrch which caches the task retries and while the PG is locked by PfcWdZeroBufferHandler.

Revert changes related to sonic-net#2164 in PfcWdZeroBufferHandler & ZeroBufferProfile & BufferOrch.

Updated UT's accordingly

How I verified it
UT's.
Ran the sonic-mgmt test with these changes sonic-net/sonic-mgmt#5665 and verified if they've passed.

Signed-off-by: Vivek Reddy Karri <[email protected]>

Author: vivekrnv

orchagent/bufferorch.cpp

@@ -48,11 +48,7 @@ BufferOrch::BufferOrch(DBConnector *applDb, DBConnector *confDb, DBConnector *st
     m_flexCounterTable(new ProducerTable(m_flexCounterDb.get(), FLEX_COUNTER_TABLE)),
     m_flexCounterGroupTable(new ProducerTable(m_flexCounterDb.get(), FLEX_COUNTER_GROUP_TABLE)),
     m_countersDb(new DBConnector("COUNTERS_DB", 0)),
-    m_stateBufferMaximumValueTable(stateDb, STATE_BUFFER_MAXIMUM_VALUE_TABLE),
-    m_ingressZeroBufferPool(SAI_NULL_OBJECT_ID),
-    m_egressZeroBufferPool(SAI_NULL_OBJECT_ID),
-    m_ingressZeroPoolRefCount(0),
-    m_egressZeroPoolRefCount(0)
+    m_stateBufferMaximumValueTable(stateDb, STATE_BUFFER_MAXIMUM_VALUE_TABLE)
 {
     SWSS_LOG_ENTER();
     initTableHandlers();
@@ -314,65 +310,6 @@ const object_reference_map &BufferOrch::getBufferPoolNameOidMap(void)
     return *m_buffer_type_maps[APP_BUFFER_POOL_TABLE_NAME];
 }
 
-void BufferOrch::lockZeroBufferPool(bool ingress)
-{
-    if (ingress)
-        m_ingressZeroPoolRefCount++;
-    else
-        m_egressZeroPoolRefCount++;
-}
-
-void BufferOrch::unlockZeroBufferPool(bool ingress)
-{
-    sai_object_id_t pool = SAI_NULL_OBJECT_ID;
-    if (ingress)
-    {
-        if (--m_ingressZeroPoolRefCount <= 0)
-        {
-            pool = m_ingressZeroBufferPool;
-            m_ingressZeroBufferPool = SAI_NULL_OBJECT_ID;
-        }
-    }
-    else
-    {
-        if (--m_egressZeroPoolRefCount <= 0)
-        {
-            pool = m_egressZeroBufferPool;
-            m_egressZeroBufferPool = SAI_NULL_OBJECT_ID;
-        }
-    }
-
-    if (pool != SAI_NULL_OBJECT_ID)
-    {
-        auto sai_status = sai_buffer_api->remove_buffer_pool(pool);
-        if (SAI_STATUS_SUCCESS != sai_status)
-        {
-            SWSS_LOG_ERROR("Failed to remove buffer pool, rv:%d", sai_status);
-            task_process_status handle_status = handleSaiRemoveStatus(SAI_API_BUFFER, sai_status);
-            if (handle_status != task_process_status::task_success)
-            {
-                return;
-            }
-        }
-        else
-        {
-            SWSS_LOG_NOTICE("Zero buffer pool has been successfully removed");
-        }
-    }
-}
-
-void BufferOrch::setZeroBufferPool(bool ingress, sai_object_id_t pool)
-{
-    if (ingress)
-    {
-        m_ingressZeroBufferPool = pool;
-    }
-    else
-    {
-        m_egressZeroBufferPool = pool;
-    }
-}
-
 task_process_status BufferOrch::processBufferPool(KeyOpFieldsValuesTuple &tuple)
 {
     SWSS_LOG_ENTER();
@@ -381,8 +318,6 @@ task_process_status BufferOrch::processBufferPool(KeyOpFieldsValuesTuple &tuple)
     string map_type_name = APP_BUFFER_POOL_TABLE_NAME;
     string object_name = kfvKey(tuple);
     string op = kfvOp(tuple);
-    sai_buffer_pool_type_t pool_direction = SAI_BUFFER_POOL_TYPE_INGRESS;
-    bool creating_zero_pool = false;
 
     SWSS_LOG_DEBUG("object name:%s", object_name.c_str());
     if (m_buffer_type_maps[map_type_name]->find(object_name) != m_buffer_type_maps[map_type_name]->end())
@@ -396,16 +331,6 @@ task_process_status BufferOrch::processBufferPool(KeyOpFieldsValuesTuple &tuple)
         }
     }
     SWSS_LOG_DEBUG("processing command:%s", op.c_str());
-    if (object_name == "ingress_zero_pool")
-    {
-        creating_zero_pool = true;
-        pool_direction = SAI_BUFFER_POOL_TYPE_INGRESS;
-    }
-    else if (object_name == "egress_zero_pool")
-    {
-        creating_zero_pool = true;
-        pool_direction = SAI_BUFFER_POOL_TYPE_EGRESS;
-    }
 
     if (op == SET_COMMAND)
     {
@@ -453,11 +378,6 @@ task_process_status BufferOrch::processBufferPool(KeyOpFieldsValuesTuple &tuple)
                     return task_process_status::task_invalid_entry;
                 }
                 attr.id = SAI_BUFFER_POOL_ATTR_TYPE;
-                if (creating_zero_pool && pool_direction != static_cast<sai_buffer_pool_type_t>(attr.value.u32))
-                {
-                    SWSS_LOG_ERROR("Wrong pool direction for pool %s", object_name.c_str());
-                    return task_process_status::task_invalid_entry;
-                }
                 attribs.push_back(attr);
             }
             else if (field == buffer_pool_mode_field_name)
@@ -523,54 +443,20 @@ task_process_status BufferOrch::processBufferPool(KeyOpFieldsValuesTuple &tuple)
         }
         else
         {
-            if (creating_zero_pool)
-            {
-                if (pool_direction == SAI_BUFFER_POOL_TYPE_INGRESS)
-                {
-                    sai_object = m_ingressZeroBufferPool;
-                }
-                else if (pool_direction == SAI_BUFFER_POOL_TYPE_EGRESS)
-                {
-                    sai_object = m_egressZeroBufferPool;
-                }
-            }
-
-            if (SAI_NULL_OBJECT_ID == sai_object)
-            {
-                sai_status = sai_buffer_api->create_buffer_pool(&sai_object, gSwitchId, (uint32_t)attribs.size(), attribs.data());
-                if (SAI_STATUS_SUCCESS != sai_status)
-                {
-                    SWSS_LOG_ERROR("Failed to create buffer pool %s with type %s, rv:%d", object_name.c_str(), map_type_name.c_str(), sai_status);
-                    task_process_status handle_status = handleSaiCreateStatus(SAI_API_BUFFER, sai_status);
-                    if (handle_status != task_process_status::task_success)
-                    {
-                        return handle_status;
-                    }
-                }
-
-                SWSS_LOG_NOTICE("Created buffer pool %s with type %s", object_name.c_str(), map_type_name.c_str());
-            }
-            else
-            {
-                SWSS_LOG_NOTICE("No need to create buffer pool %s since it has been created", object_name.c_str());
-            }
-
-            if (creating_zero_pool)
+            sai_status = sai_buffer_api->create_buffer_pool(&sai_object, gSwitchId, (uint32_t)attribs.size(), attribs.data());
+            if (SAI_STATUS_SUCCESS != sai_status)
             {
-                if (pool_direction == SAI_BUFFER_POOL_TYPE_INGRESS)
-                {
-                    m_ingressZeroPoolRefCount++;
-                    m_ingressZeroBufferPool = sai_object;
-                }
-                else if (pool_direction == SAI_BUFFER_POOL_TYPE_EGRESS)
+                SWSS_LOG_ERROR("Failed to create buffer pool %s with type %s, rv:%d", object_name.c_str(), map_type_name.c_str(), sai_status);
+                task_process_status handle_status = handleSaiCreateStatus(SAI_API_BUFFER, sai_status);
+                if (handle_status != task_process_status::task_success)
                 {
-                    m_egressZeroPoolRefCount++;
-                    m_egressZeroBufferPool = sai_object;
+                    return handle_status;
                 }
             }
 
             (*(m_buffer_type_maps[map_type_name]))[object_name].m_saiObjectId = sai_object;
             (*(m_buffer_type_maps[map_type_name]))[object_name].m_pendingRemove = false;
+            SWSS_LOG_NOTICE("Created buffer pool %s with type %s", object_name.c_str(), map_type_name.c_str());
             // Here we take the PFC watchdog approach to update the COUNTERS_DB metadata (e.g., PFC_WD_DETECTION_TIME per queue)
             // at initialization (creation and registration phase)
             // Specifically, we push the buffer pool name to oid mapping upon the creation of the oid
@@ -593,39 +479,17 @@ task_process_status BufferOrch::processBufferPool(KeyOpFieldsValuesTuple &tuple)
         if (SAI_NULL_OBJECT_ID != sai_object)
         {
             clearBufferPoolWatermarkCounterIdList(sai_object);
-            bool remove = true;
-            if (sai_object == m_ingressZeroBufferPool)
-            {
-                if (--m_ingressZeroPoolRefCount > 0)
-                    remove = false;
-                else
-                    m_ingressZeroBufferPool = SAI_NULL_OBJECT_ID;
-            }
-            else if (sai_object == m_egressZeroBufferPool)
-            {
-                if (--m_egressZeroPoolRefCount > 0)
-                    remove = false;
-                else
-                    m_egressZeroBufferPool = SAI_NULL_OBJECT_ID;
-            }
-            if (remove)
+            sai_status = sai_buffer_api->remove_buffer_pool(sai_object);
+            if (SAI_STATUS_SUCCESS != sai_status)
             {
-                sai_status = sai_buffer_api->remove_buffer_pool(sai_object);
-                if (SAI_STATUS_SUCCESS != sai_status)
+                SWSS_LOG_ERROR("Failed to remove buffer pool %s with type %s, rv:%d", object_name.c_str(), map_type_name.c_str(), sai_status);
+                task_process_status handle_status = handleSaiRemoveStatus(SAI_API_BUFFER, sai_status);
+                if (handle_status != task_process_status::task_success)
                 {
-                    SWSS_LOG_ERROR("Failed to remove buffer pool %s with type %s, rv:%d", object_name.c_str(), map_type_name.c_str(), sai_status);
-                    task_process_status handle_status = handleSaiRemoveStatus(SAI_API_BUFFER, sai_status);
-                    if (handle_status != task_process_status::task_success)
-                    {
-                        return handle_status;
-                    }
+                    return handle_status;
                 }
-                SWSS_LOG_NOTICE("Removed buffer pool %s with type %s", object_name.c_str(), map_type_name.c_str());
-            }
-            else
-            {
-                SWSS_LOG_NOTICE("Will not remove buffer pool %s since it is still referenced", object_name.c_str());
             }
+            SWSS_LOG_NOTICE("Removed buffer pool %s with type %s", object_name.c_str(), map_type_name.c_str());
         }
         auto it_to_delete = (m_buffer_type_maps[map_type_name])->find(object_name);
         (m_buffer_type_maps[map_type_name])->erase(it_to_delete);
@@ -1049,7 +913,6 @@ task_process_status BufferOrch::processPriorityGroup(KeyOpFieldsValuesTuple &tup
     for (string port_name : port_names)
     {
         Port port;
-        bool portUpdated = false;
         SWSS_LOG_DEBUG("processing port:%s", port_name.c_str());
         if (!gPortsOrch->getPort(port_name, port))
         {
@@ -1064,12 +927,6 @@ task_process_status BufferOrch::processPriorityGroup(KeyOpFieldsValuesTuple &tup
                 SWSS_LOG_ERROR("Invalid pg index specified:%zd", ind);
                 return task_process_status::task_invalid_entry;
             }
-            if (port.m_priority_group_lock[ind])
-            {
-                SWSS_LOG_WARN("Priority group %zd on port %s is locked, pending profile 0x%" PRIx64 " until unlocked", ind, port_name.c_str(), sai_buffer_profile);
-                portUpdated = true;
-                port.m_priority_group_pending_profile[ind] = sai_buffer_profile;
-            }
             else
             {
                 if (need_update_sai)
@@ -1090,10 +947,6 @@ task_process_status BufferOrch::processPriorityGroup(KeyOpFieldsValuesTuple &tup
                 }
             }
         }
-        if (portUpdated)
-        {
-            gPortsOrch->setPort(port_name, port);
-        }
     }
 
     if (m_ready_list.find(key) != m_ready_list.end())

orchagent/bufferorch.h

@@ -37,14 +37,6 @@ class BufferOrch : public Orch
     static type_map m_buffer_type_maps;
     void generateBufferPoolWatermarkCounterIdList(void);
     const object_reference_map &getBufferPoolNameOidMap(void);
-    sai_object_id_t getZeroBufferPool(bool ingress)
-    {
-        return ingress ? m_ingressZeroBufferPool : m_egressZeroBufferPool;
-    }
-
-    void lockZeroBufferPool(bool ingress);
-    void unlockZeroBufferPool(bool ingress);
-    void setZeroBufferPool(bool direction, sai_object_id_t pool);
 
 private:
     typedef task_process_status (BufferOrch::*buffer_table_handler)(KeyOpFieldsValuesTuple &tuple);
@@ -80,10 +72,6 @@ class BufferOrch : public Orch
 
     bool m_isBufferPoolWatermarkCounterIdListGenerated = false;
 
-    sai_object_id_t m_ingressZeroBufferPool;
-    sai_object_id_t m_egressZeroBufferPool;
-    int m_ingressZeroPoolRefCount;
-    int m_egressZeroPoolRefCount;
 };
 #endif /* SWSS_BUFFORCH_H */