[Dynamic buffer calculation][Mellanox] Enhance the logic to identify buffer pools and profiles (sonic-net#2498)

Signed-off-by: Stephen Sun <[email protected]>

What I did
Originally, it was assumed the names of all the buffer pools follow the community buffer pool name convention ({ingress|egress}_{lossless|lossy}_pool). The heuristic algorithm to identify buffer pools and profiles was designed based on the assumption.
However, some users can define the buffer pool names in other ways, which breaks the logic in the Lua plugin and introduces degradation,

the pool sizes of those pools can not be generated
the additional reserved memory for lossy PG can not be calculated
In this PR, the logic is improved to tolerate the case.
Signed-off-by: Stephen Sun [email protected]

How I verified it
Manually and regression test.
It has been covered by regression test and vs test. No new test case is required.

Details if related
Separate the buffer pools into two tables according to the direction.
Iterate all the profiles, generating and recording the type (lossless/lossy) for each ingress profile which is identified by checking the pool it references
Identify buffer profiles for lossy PG by checking the type (lossless/lossy) generated in 2 instead of the hardcoded name ingress_lossy_profile

Author: stephenxs

cfgmgr/buffer_pool_mellanox.lua

@@ -10,12 +10,13 @@ local port_count_8lanes = 0
 -- Number of lossy PG on ports with 8 lanes
 local lossypg_8lanes = 0
 
+local ingress_profile_is_lossless = {}
+
 -- Private headrom
 local private_headroom = 10 * 1024
 
 local result = {}
 local profiles = {}
-local lossless_profiles = {}
 
 local total_port = 0
 
@@ -52,11 +53,11 @@ local function iterate_all_items(all_items, check_lossless)
         port = string.match(all_items[i], "Ethernet%d+")
         if port ~= nil then
             local range = string.match(all_items[i], "Ethernet%d+:([^%s]+)$")
-            local profile_name = redis.call('HGET', all_items[i], 'profile')
-            if not profile_name then
+            local profile_name_without_table = redis.call('HGET', all_items[i], 'profile')
+            if not profile_name_without_table then
                 return 1
             end
-            profile_name = "BUFFER_PROFILE_TABLE:" .. profile_name
+            local profile_name = "BUFFER_PROFILE_TABLE:" .. profile_name_without_table
             local profile_ref_count = profiles[profile_name]
             if profile_ref_count == nil then
                 -- Indicate an error in case the referenced profile hasn't been inserted or has been removed
@@ -71,10 +72,11 @@ local function iterate_all_items(all_items, check_lossless)
                 size = 1 + tonumber(string.sub(range, -1)) - tonumber(string.sub(range, 1, 1))
             end
             profiles[profile_name] = profile_ref_count + size
-            if port_set_8lanes[port] and profile_name == 'BUFFER_PROFILE_TABLE:ingress_lossy_profile' then
+            if port_set_8lanes[port] and ingress_profile_is_lossless[profile_name] == false then
+                -- Handle additional buffer reserved for lossy PG on 8-lane ports
                 lossypg_8lanes = lossypg_8lanes + size
             end
-            if check_lossless and lossless_profiles[profile_name] then
+            if check_lossless and ingress_profile_is_lossless[profile_name] then
                 if lossless_ports[port] == nil then
                     lossless_port_count = lossless_port_count + 1
                     lossless_ports[port] = true
@@ -113,7 +115,8 @@ local function iterate_profile_list(all_items)
             -- To distinguish both cases, a new name "ingress_lossy_profile_list" is introduced to indicate
             -- the profile is used by the profile list where its size should be zero.
             profile_name = 'BUFFER_PROFILE_TABLE:' .. profile_name
-            if profile_name == 'BUFFER_PROFILE_TABLE:ingress_lossy_profile' then
+            -- TODO CHECK ALL LOSSY PROFILES
+            if ingress_profile_is_lossless[profile_name] == false then
                 profile_name = profile_name .. '_list'
                 if profiles[profile_name] == nil then
                     profiles[profile_name] = 0
@@ -162,9 +165,25 @@ local function fetch_buffer_pool_size_from_appldb()
     end
 end
 
+-- Main --
 -- Connect to CONFIG_DB
 redis.call('SELECT', config_db)
 
+-- Parse all the pools and seperate them according to the direction
+local ipools = {}
+local epools = {}
+local pools = redis.call('KEYS', 'BUFFER_POOL|*')
+for i = 1, #pools, 1 do
+    local type = redis.call('HGET', pools[i], 'type')
+    if type == 'ingress' then
+        table.insert(ipools, pools[i])
+    else
+        if type == 'egress' then
+            table.insert(epools, pools[i])
+        end
+    end
+end
+
 local ports_table = redis.call('KEYS', 'PORT|*')
 
 total_port = #ports_table
@@ -250,9 +269,19 @@ redis.call('SELECT', appl_db)
 local all_profiles = redis.call('KEYS', 'BUFFER_PROFILE*')
 for i = 1, #all_profiles, 1 do
     if all_profiles[i] ~= "BUFFER_PROFILE_TABLE_KEY_SET" and all_profiles[i] ~= "BUFFER_PROFILE_TABLE_DEL_SET" then
-        local xoff = redis.call('HGET', all_profiles[i], 'xoff')
-        if xoff then
-            lossless_profiles[all_profiles[i]] = true
+        local pool = redis.call('HGET', all_profiles[i], 'pool')
+        for j = 1, #ipools, 1 do
+            if "BUFFER_POOL|" .. pool == ipools[j] then
+                -- For ingress profiles, check whether it is lossless or lossy
+                -- For lossy profiles, there is buffer implicitly reserved when they are applied on PGs
+                local xoff = redis.call('HGET', all_profiles[i], 'xoff')
+                if xoff then
+                    ingress_profile_is_lossless[all_profiles[i]] = true
+                else
+                    ingress_profile_is_lossless[all_profiles[i]] = false
+                end
+                break
+            end
         end
         profiles[all_profiles[i]] = 0
     end
@@ -289,9 +318,10 @@ local accumulative_xoff = 0
 for name in pairs(profiles) do
     if name ~= "BUFFER_PROFILE_TABLE_KEY_SET" and name ~= "BUFFER_PROFILE_TABLE_DEL_SET" then
         local size = tonumber(redis.call('HGET', name, 'size'))
-        if size ~= nil then 
-            if name == "BUFFER_PROFILE_TABLE:ingress_lossy_profile" then
-                size = size + lossypg_reserved
+        if size ~= nil then
+            -- Handle the implicitly reserved buffer for lossy profile applied on PG
+            if ingress_profile_is_lossless[name] == false then
+               size = size + lossypg_reserved
             end
             if size ~= 0 then
                 if shp_enabled and shp_size == 0 then
@@ -304,6 +334,8 @@ for name in pairs(profiles) do
                 accumulative_occupied_buffer = accumulative_occupied_buffer + size * profiles[name]
             end
             table.insert(statistics, {name, size, profiles[name]})
+        else
+            table.insert(statistics, {name, "-", profiles[name]})
         end
     end
 end
@@ -336,7 +368,6 @@ redis.call('SELECT', config_db)
 
 -- Fetch all the pools that need update
 local pools_need_update = {}
-local ipools = redis.call('KEYS', 'BUFFER_POOL|ingress*')
 local ingress_pool_count = 0
 local ingress_lossless_pool_size = nil
 for i = 1, #ipools, 1 do
@@ -351,7 +382,6 @@ for i = 1, #ipools, 1 do
     end
 end
 
-local epools = redis.call('KEYS', 'BUFFER_POOL|egress*')
 for i = 1, #epools, 1 do
     local size = redis.call('HGET', epools[i], 'size')
     if not size then