[dash-p4] Add tunnel member table and tunnel next hop table. (#622)

To support the ECMP group in the tunnel, this change adds the tunnel
member and tunnel next hop tables using the same way as how next hop
group works today in SAI.

The detailed design is following the HLD defined here:
https://github.com/sonic-net/DASH/blob/main/documentation/private-link-service/private-link-service.md.

dash-pipeline/SAI/specs/dash_tunnel.yaml

@@ -30,7 +30,7 @@ sai_apis:
     attr_value_field: s32
     default: SAI_DASH_ENCAPSULATION_VXLAN
     isresourcetype: false
-    flags: CREATE_AND_SET
+    flags: CREATE_ONLY
     object_name: null
     allow_null: false
     valid_only: null
@@ -43,6 +43,32 @@ sai_apis:
     attr_value_field: u32
     default: '0'
     isresourcetype: false
+    flags: CREATE_ONLY
+    object_name: null
+    allow_null: false
+    valid_only: null
+    is_vlan: false
+    deprecated: false
+  - !!python/object:utils.sai_spec.sai_attribute.SaiAttribute
+    name: SAI_DASH_TUNNEL_ATTR_MAX_MEMBER_SIZE
+    description: Action parameter max member size
+    type: sai_uint32_t
+    attr_value_field: u32
+    default: '1'
+    isresourcetype: false
+    flags: CREATE_ONLY
+    object_name: null
+    allow_null: false
+    valid_only: null
+    is_vlan: false
+    deprecated: false
+  - !!python/object:utils.sai_spec.sai_attribute.SaiAttribute
+    name: SAI_DASH_TUNNEL_ATTR_SIP
+    description: Action parameter sip
+    type: sai_ip_address_t
+    attr_value_field: ipaddr
+    default: 0.0.0.0
+    isresourcetype: false
     flags: CREATE_AND_SET
     object_name: null
     allow_null: false
@@ -59,3 +85,76 @@ sai_apis:
           name: default
           id: 27891720
           attr_param_id: {}
+- !!python/object:utils.sai_spec.sai_api.SaiApi
+  name: dash_tunnel_member
+  description: DASH tunnel member
+  is_object: true
+  enums: []
+  structs: []
+  attributes:
+  - !!python/object:utils.sai_spec.sai_attribute.SaiAttribute
+    name: SAI_DASH_TUNNEL_MEMBER_ATTR_DASH_TUNNEL_ID
+    description: Action parameter DASH tunnel id
+    type: sai_object_id_t
+    attr_value_field: u16
+    default: null
+    isresourcetype: false
+    flags: MANDATORY_ON_CREATE | CREATE_ONLY
+    object_name: SAI_OBJECT_TYPE_DASH_TUNNEL
+    allow_null: false
+    valid_only: null
+    is_vlan: false
+    deprecated: false
+  - !!python/object:utils.sai_spec.sai_attribute.SaiAttribute
+    name: SAI_DASH_TUNNEL_MEMBER_ATTR_DASH_TUNNEL_NEXT_HOP_ID
+    description: Action parameter DASH tunnel next hop id
+    type: sai_object_id_t
+    attr_value_field: u16
+    default: null
+    isresourcetype: false
+    flags: MANDATORY_ON_CREATE | CREATE_AND_SET
+    object_name: SAI_OBJECT_TYPE_DASH_TUNNEL_NEXT_HOP
+    allow_null: false
+    valid_only: null
+    is_vlan: false
+    deprecated: false
+  stats: []
+  p4_meta: !!python/object:utils.sai_spec.sai_api_p4_meta.SaiApiP4Meta
+    tables:
+    - !!python/object:utils.sai_spec.sai_api_p4_meta.SaiApiP4MetaTable
+      id: 40012474
+      actions:
+        default: !!python/object:utils.sai_spec.sai_api_p4_meta.SaiApiP4MetaAction
+          name: default
+          id: 23738116
+          attr_param_id: {}
+- !!python/object:utils.sai_spec.sai_api.SaiApi
+  name: dash_tunnel_next_hop
+  description: DASH tunnel next hop
+  is_object: true
+  enums: []
+  structs: []
+  attributes:
+  - !!python/object:utils.sai_spec.sai_attribute.SaiAttribute
+    name: SAI_DASH_TUNNEL_NEXT_HOP_ATTR_DIP
+    description: Action parameter dip
+    type: sai_ip_address_t
+    attr_value_field: ipaddr
+    default: 0.0.0.0
+    isresourcetype: false
+    flags: CREATE_AND_SET
+    object_name: null
+    allow_null: false
+    valid_only: null
+    is_vlan: false
+    deprecated: false
+  stats: []
+  p4_meta: !!python/object:utils.sai_spec.sai_api_p4_meta.SaiApiP4Meta
+    tables:
+    - !!python/object:utils.sai_spec.sai_api_p4_meta.SaiApiP4MetaTable
+      id: 34229686
+      actions:
+        default: !!python/object:utils.sai_spec.sai_api_p4_meta.SaiApiP4MetaAction
+          name: default
+          id: 31749609
+          attr_param_id: {}

dash-pipeline/SAI/specs/sai_spec.yaml

@@ -41,6 +41,8 @@ object_types:
 - SAI_OBJECT_TYPE_FLOW_ENTRY_BULK_GET_SESSION
 - SAI_OBJECT_TYPE_METER_BUCKET_ENTRY
 - SAI_OBJECT_TYPE_DASH_APPLIANCE
+- SAI_OBJECT_TYPE_DASH_TUNNEL_MEMBER
+- SAI_OBJECT_TYPE_DASH_TUNNEL_NEXT_HOP
 object_entries:
 - !!python/object:utils.sai_spec.sai_struct_entry.SaiStructEntry
   name: direction_lookup_entry

dash-pipeline/SAI/templates/saiapi.cpp.j2

@@ -59,15 +59,16 @@ static sai_status_t dash_sai_create_{{ table.name }}(
 
     matchActionEntry->set_table_id(tableId);
 
-    {% if table['keys'] | length== 1 %}
-    // SAI object table with single P4 key - object ID itself is the P4 table key
-    // Generate a SAI object ID and fill it as the P4 table key
-    auto mf = matchActionEntry->add_match();
-    mf->set_field_id({{table['keys'][0].id}});
-    auto mf_exact = mf->mutable_exact();
-    //{{table['keys'][0].field}}SetVal(objId, mf_exact, {{table['keys'][0].bitwidth}});
-      {{table['keys'][0].field}}SetVal(static_cast<uint{{ table['keys'][0].bitwidth }}_t>(objId), mf_exact, {{ table['keys'][0].bitwidth }}); 
-    {% else %}
+    {% for key in table['keys'] %}
+    {% if key.is_object_key %}
+    auto key_mf = matchActionEntry->add_match();
+    key_mf->set_field_id({{key.id}});
+    auto key_mf_exact = key_mf->mutable_exact();
+    // {{key.field}}SetVal(objId, key_mf_exact, {{key.bitwidth}});
+    {{key.field}}SetVal(static_cast<uint{{ key.bitwidth }}_t>(objId), key_mf_exact, {{ key.bitwidth }}); 
+    {% endif %}
+    {% endfor %}
+
     // SAI object table with multiple P4 table keys
     // Copy P4 table keys from appropriate SAI attributes
     for (uint32_t i = 0; i < attr_count; i++)
@@ -79,6 +80,7 @@ static sai_status_t dash_sai_create_{{ table.name }}(
         switch(attr_list[i].id)
         {
             {% for key in table['keys'] %}
+            {% if not key.is_object_key %}
             case SAI_{{ table.name | upper }}_ATTR_{{ key.name | upper }}:
             {
                 auto mf = matchActionEntry->add_match();
@@ -138,6 +140,7 @@ static sai_status_t dash_sai_create_{{ table.name }}(
                 {% endif %}
                 break;
             }
+            {% endif%}
             {% endfor %}
             {% if table['keys'] | selectattr('match_type', 'ne', 'exact') | list | length > 0 %}
             {% if table['keys'] | selectattr('match_type', 'eq', 'lpm') | list | length == 0 %}
@@ -154,7 +157,6 @@ static sai_status_t dash_sai_create_{{ table.name }}(
                 break;
         }
     }
-    {% endif %}
 
     // If there is only one action, simply set it.
     // Else, search in the attrs.

dash-pipeline/SAI/templates/saiapi.h.j2

@@ -166,6 +166,8 @@ typedef enum _sai_{{ table.name }}_attr_t
      * @type {{ sai_attr.type }}
 {% if sai_attr.isreadonly == 'true' %}
      * @flags READ_ONLY
+{% else if sai_attr.is_create_only == 'true' %}
+     * @flags CREATE_ONLY
 {% else %}
      * @flags CREATE_AND_SET
 {% endif %}

dash-pipeline/SAI/utils/dash_p4/dash_p4_table.py

@@ -127,7 +127,7 @@ def __table_with_counters(self, program: Dict[str, Any]) -> None:
     def __parse_table_keys(self, p4rt_table: Dict[str, Any]) -> None:
         for p4rt_table_key in p4rt_table[MATCH_FIELDS_TAG]:
             table_key = DashP4TableKey.from_p4rt(p4rt_table_key)
-
+            
             if self.is_object != "false":
                 table_key.is_entry_key = False
 
@@ -372,9 +372,13 @@ def create_sai_stats(self, sai_api: SaiApi) -> None:
 
     def create_sai_attributes(self, sai_api: SaiApi) -> None:
         # If the table is an object with more one key (table entry id), we need to add all the keys into the attributes.
-        if self.is_object == "true" and len(self.keys) > 1:
-            for key in self.keys:
-                sai_api.attributes.extend(key.to_sai_attribute(self.name, create_only=True))
+        if self.is_object == "true":
+            if len(self.keys) == 1:
+                self.keys[0].is_object_key = True
+            elif len(self.keys) > 1:
+                for key in self.keys:
+                    if not key.is_object_key:
+                        sai_api.attributes.extend(key.to_sai_attribute(self.name))
 
         # Add all the action parameters into the attributes.
         for attr in self.sai_attributes:

dash-pipeline/SAI/utils/dash_p4/dash_p4_table_attribute.py

@@ -15,10 +15,13 @@ def __init__(self):
         self.bitwidth: int = 0
         self.isresourcetype: Optional[str] = None
         self.isreadonly: Optional[str] = None
+        self.is_create_only: Optional[str] = None
+        self.is_mandatory: Optional[str] = None
         self.object_name: Optional[str] = None
         self.skipattr: Optional[str] = None
         self.match_type: str = ""
         self.validonly: Optional[str] = None
+        self.is_object_key: bool = False
 
     def _parse_sai_table_attribute_annotation(
         self, p4rt_anno_list: Dict[str, Any]
@@ -58,6 +61,10 @@ def _parse_sai_table_attribute_annotation(
                         self.isresourcetype = str(kv["value"]["stringValue"])
                     elif kv["key"] == "isreadonly":
                         self.isreadonly = str(kv["value"]["stringValue"])
+                    elif kv["key"] == "create_only":
+                        self.is_create_only = str(kv["value"]["stringValue"])
+                    elif kv["key"] == "mandatory":
+                        self.is_mandatory = str(kv["value"]["stringValue"])
                     elif kv["key"] == "objects":
                         self.object_name = str(kv["value"]["stringValue"])
                     elif kv["key"] == "skipattr":
@@ -66,6 +73,8 @@ def _parse_sai_table_attribute_annotation(
                         self.match_type = str(kv["value"]["stringValue"])
                     elif kv["key"] == "validonly":
                         self.validonly = str(kv["value"]["stringValue"])
+                    elif kv["key"] == "is_object_key":
+                        self.is_object_key = kv["value"]["stringValue"] == "true"
                     else:
                         raise ValueError("Unknown attr annotation " + kv["key"])
 
@@ -122,7 +131,7 @@ def to_sai_struct_entry(self, table_name: str) -> List[SaiStructEntry]:
 
         return entries
 
-    def to_sai_attribute(self, table_name: str, create_only: bool = False, add_action_valid_only_check: bool = False) -> List[SaiAttribute]:
+    def to_sai_attribute(self, table_name: str, add_action_valid_only_check: bool = False) -> List[SaiAttribute]:
         name = self.get_sai_name(table_name)
         description = self.get_sai_description(table_name)
 
@@ -133,13 +142,24 @@ def to_sai_attribute(self, table_name: str, create_only: bool = False, add_actio
         if self.isreadonly == "true":
             sai_flags = "READ_ONLY"
             default_value = None
-        elif create_only:
-            sai_flags = "MANDATORY_ON_CREATE | CREATE_ONLY"
-            default_value = None
+        elif self.is_create_only == "true":
+            if self.default == None or self.is_mandatory == "true":
+                sai_flags = "MANDATORY_ON_CREATE | CREATE_ONLY"
+                default_value = None
+                allow_null = False
+            else:
+                sai_flags = "CREATE_ONLY"
+                default_value = self.default
+
             allow_null = False
         else:
-            sai_flags = "CREATE_AND_SET"
-            default_value = self.default
+            if self.is_mandatory == "true":
+                sai_flags = "MANDATORY_ON_CREATE | CREATE_AND_SET"
+                default_value = None
+                allow_null = False
+            else:
+                sai_flags = "CREATE_AND_SET"
+                default_value = self.default
 
         valid_only_checks = []
         if add_action_valid_only_check:

dash-pipeline/SAI/utils/dash_p4/dash_p4_table_key.py

@@ -11,6 +11,8 @@ class DashP4TableKey(DashP4TableAttribute):
 
     def __init__(self):
         super().__init__()
+        self.is_create_only: str = "true"
+        self.is_mandatory: str = "true"
         self.ip_is_v6_field_id: int = 0
 
     def parse_p4rt(self, p4rt_table_key: Dict[str, Any]) -> None:
@@ -55,6 +57,9 @@ def parse_p4rt(self, p4rt_table_key: Dict[str, Any]) -> None:
 
         self.set_sai_type(sai_type_info)
 
+        # For table keys, we currently require the values to be explicitly set.
+        self.default = None
+
         return
 
     #

dash-pipeline/bmv2/README.md

@@ -30,7 +30,9 @@ Available tags are:
 - `default_value`: Override the default value for this key or action parameter.
 - `isresourcetype`: When set to "true", we generate a corresponding SAI tag in SAI APIs: `@isresourcetype true`.
 - `objects`: Space separated list of SAI object type this value accepts. When set, we force this value to be a SAI object id, and generate a corresponding SAI tag in SAI APIs: `@objects <list>`.
-- `isreadonly`: When set to "true", we generate force this value to be read-only in SAI API using: `@flags READ_ONLY`, otherwise, we generate `@flags CREATE_AND_SET`.
+- `isreadonly`: When set to "true", we generate force this value to be read-only in SAI API using: `@flags READ_ONLY`, otherwise, we generate `@flags CREATE_AND_SET`. It cannot be used with `iscreateonly`.
+- `iscreateonly`: When set to "true", we generate force this value to be create-only in SAI API using: `@flags CREATE_ONLY`, otherwise, we generate `@flags CREATE_AND_SET`. It cannot be used with `isreadonly`.
+- `ismandatory`: When set to "true", we generate force this value to be mandatory in SAI API using: `@flags MANDATORY_ON_CREATE`. It cannot be used with `isreadonly`.
 - `skipattr`: When set to "true", we skip this attribute in SAI API generation.
 
 #### `@SaiCounter`: Counters

dash-pipeline/bmv2/dash_metadata.p4

@@ -326,6 +326,10 @@ struct metadata_t {
     IPv4Address reverse_tunnel_sip;
     overlay_rewrite_data_t overlay_data;
     bit<16> dash_tunnel_id;
+    bit<32> dash_tunnel_max_member_size;
+    bit<16> dash_tunnel_member_index;
+    bit<16> dash_tunnel_member_id;
+    bit<16> dash_tunnel_next_hop_id;
     bit<32> meter_class;
     bit<8> local_region_id;
 }