[Feat] allow recycle/burn toggle from burn uid

pallets/admin-utils/src/lib.rs

@@ -1493,6 +1493,38 @@ pub mod pallet {
             res
         }
 
+        /// Set the behaviour of the "burn" UID(s) for a given subnet.
+        /// If set to `Burn`, the miner emission sent to the burn UID(s) will be burned.
+        /// If set to `Recycle`, the miner emission sent to the burn UID(s) will be recycled.
+        ///
+        /// # Parameters
+        /// - `origin`: The origin of the call, which must be the root account or subnet owner.
+        /// - `netuid`: The unique identifier for the subnet.
+        /// - `recycle_or_burn`: The desired behaviour of the "burn" UID(s) for the subnet.
+        ///
+        #[pallet::call_index(80)]
+        #[pallet::weight((1_000_000, DispatchClass::Normal, Pays::Yes))] // TODO: add proper weights
+        pub fn sudo_set_recycle_or_burn(
+            origin: OriginFor<T>,
+            netuid: NetUid,
+            recycle_or_burn: pallet_subtensor::RecycleOrBurnEnum,
+        ) -> DispatchResult {
+            let maybe_owner = pallet_subtensor::Pallet::<T>::ensure_sn_owner_or_root_with_limits(
+                origin,
+                netuid,
+                &[Hyperparameter::RecycleOrBurn.into()],
+            )?;
+
+            pallet_subtensor::Pallet::<T>::set_recycle_or_burn(netuid, recycle_or_burn);
+            pallet_subtensor::Pallet::<T>::record_owner_rl(
+                maybe_owner,
+                netuid,
+                &[Hyperparameter::RecycleOrBurn.into()],
+            );
+
+            Ok(())
+        }
+
         /// Toggles the enablement of an EVM precompile.
         ///
         /// # Arguments

pallets/subtensor/src/coinbase/run_coinbase.rs

@@ -499,6 +499,17 @@ impl<T: Config> Pallet<T> {
                 log::debug!(
                     "incentives: hotkey: {hotkey:?} is SN owner hotkey or associated hotkey, skipping {incentive:?}"
                 );
+                // Check if we should recycle or burn the incentive
+                match RecycleOrBurn::<T>::try_get(netuid) {
+                    Ok(RecycleOrBurnEnum::Recycle) => {
+                        log::debug!("recycling {incentive:?}");
+                        Self::recycle_subnet_alpha(netuid, incentive);
+                    }
+                    Ok(RecycleOrBurnEnum::Burn) | Err(_) => {
+                        log::debug!("burning {incentive:?}");
+                        Self::burn_subnet_alpha(netuid, incentive);
+                    }
+                }
                 continue;
             }
 

pallets/subtensor/src/lib.rs

@@ -305,6 +305,15 @@ pub mod pallet {
         pub additional: Vec<u8>,
     }
 
+    /// Enum for recycle or burn for the owner_uid(s)
+    #[derive(TypeInfo, Encode, Decode, DecodeWithMemTracking, Clone, PartialEq, Eq, Debug)]
+    pub enum RecycleOrBurnEnum {
+        /// Burn the miner emission sent to the burn UID
+        Burn,
+        /// Recycle the miner emission sent to the recycle UID
+        Recycle,
+    }
+
     /// ============================
     /// ==== Staking + Accounts ====
     /// ============================
@@ -538,6 +547,11 @@ pub mod pallet {
         T::InitialSubnetOwnerCut::get()
     }
     #[pallet::type_value]
+    /// Default value for recycle or burn.
+    pub fn DefaultRecycleOrBurn<T: Config>() -> RecycleOrBurnEnum {
+        RecycleOrBurnEnum::Burn // default to burn
+    }
+    #[pallet::type_value]
     /// Default value for network rate limit.
     pub fn DefaultNetworkRateLimit<T: Config>() -> u64 {
         if cfg!(feature = "pow-faucet") {
@@ -1335,6 +1349,10 @@ pub mod pallet {
     pub type SubnetOwnerHotkey<T: Config> =
         StorageMap<_, Identity, NetUid, T::AccountId, ValueQuery, DefaultSubnetOwner<T>>;
     #[pallet::storage]
+    /// --- MAP ( netuid ) --> recycle_or_burn
+    pub type RecycleOrBurn<T: Config> =
+        StorageMap<_, Identity, NetUid, RecycleOrBurnEnum, ValueQuery, DefaultRecycleOrBurn<T>>;
+    #[pallet::storage]
     /// --- MAP ( netuid ) --> serving_rate_limit
     pub type ServingRateLimit<T> =
         StorageMap<_, Identity, NetUid, u64, ValueQuery, DefaultServingRateLimit<T>>;

pallets/subtensor/src/staking/helpers.rs

@@ -323,8 +323,13 @@ impl<T: Config> Pallet<T> {
     }
 
     pub fn recycle_subnet_alpha(netuid: NetUid, amount: AlphaCurrency) {
+        // TODO: record recycled alpha in a tracker
         SubnetAlphaOut::<T>::mutate(netuid, |total| {
             *total = total.saturating_sub(amount);
         });
     }
+
+    pub fn burn_subnet_alpha(_netuid: NetUid, _amount: AlphaCurrency) {
+        // Do nothing; TODO: record burned alpha in a tracker
+    }
 }

pallets/subtensor/src/staking/recycle_alpha.rs

@@ -126,7 +126,7 @@ impl<T: Config> Pallet<T> {
             &hotkey, &coldkey, netuid, amount,
         );
 
-        // This is a burn, so we don't need to update AlphaOut.
+        Self::burn_subnet_alpha(netuid, amount);
 
         // Deposit event
         Self::deposit_event(Event::AlphaBurned(

pallets/subtensor/src/subnets/subnet.rs

@@ -229,7 +229,7 @@ impl<T: Config> Pallet<T> {
         );
 
         if actual_tao_lock_amount_less_pool_tao > TaoCurrency::ZERO {
-            Self::burn_tokens(actual_tao_lock_amount_less_pool_tao);
+            Self::recycle_tao(actual_tao_lock_amount_less_pool_tao);
         }
 
         if actual_tao_lock_amount > TaoCurrency::ZERO && pool_initial_tao > TaoCurrency::ZERO {

pallets/subtensor/src/swap/swap_coldkey.rs

@@ -62,10 +62,10 @@ impl<T: Config> Pallet<T> {
             Error::<T>::NotEnoughBalanceToPaySwapColdKey
         );
 
-        // 7. Remove and burn the swap cost from the old coldkey's account
+        // 7. Remove and recycle the swap cost from the old coldkey's account
         let actual_burn_amount =
             Self::remove_balance_from_coldkey_account(old_coldkey, swap_cost.into())?;
-        Self::burn_tokens(actual_burn_amount);
+        Self::recycle_tao(actual_burn_amount);
 
         // 8. Update the weight for the balance operations
         weight.saturating_accrue(T::DbWeight::get().reads_writes(1, 1));

pallets/subtensor/src/swap/swap_hotkey.rs

@@ -97,11 +97,11 @@ impl<T: Config> Pallet<T> {
         weight.saturating_accrue(T::DbWeight::get().reads_writes(3, 0));
 
         // 14. Remove the swap cost from the coldkey's account
-        let actual_burn_amount =
+        let actual_recycle_amount =
             Self::remove_balance_from_coldkey_account(&coldkey, swap_cost.into())?;
 
-        // 18. Burn the tokens
-        Self::burn_tokens(actual_burn_amount);
+        // 18. Recycle the tokens
+        Self::recycle_tao(actual_recycle_amount);
         weight.saturating_accrue(T::DbWeight::get().reads_writes(0, 2));
 
         // 19. Perform the hotkey swap
@@ -296,11 +296,11 @@ impl<T: Config> Pallet<T> {
         );
 
         // 5. Remove the swap cost from the coldkey's account
-        let actual_burn_amount = Self::remove_balance_from_coldkey_account(coldkey, swap_cost)?;
+        let actual_recycle_amount = Self::remove_balance_from_coldkey_account(coldkey, swap_cost)?;
         weight.saturating_accrue(T::DbWeight::get().reads_writes(1, 0));
 
-        // 6. Burn the tokens
-        Self::burn_tokens(actual_burn_amount);
+        // 6. Recycle the tokens
+        Self::recycle_tao(actual_recycle_amount);
         weight.saturating_accrue(T::DbWeight::get().reads_writes(1, 1));
 
         // 7. Swap owner.

pallets/subtensor/src/utils/misc.rs

@@ -372,7 +372,7 @@ impl<T: Config> Pallet<T> {
     // ========================
     // === Token Management ===
     // ========================
-    pub fn burn_tokens(amount: TaoCurrency) {
+    pub fn recycle_tao(amount: TaoCurrency) {
         TotalIssuance::<T>::put(TotalIssuance::<T>::get().saturating_sub(amount));
     }
     pub fn increase_issuance(amount: TaoCurrency) {
@@ -393,6 +393,10 @@ impl<T: Config> Pallet<T> {
         total_subnet_locked.into()
     }
 
+    pub fn set_recycle_or_burn(netuid: NetUid, recycle_or_burn: RecycleOrBurnEnum) {
+        RecycleOrBurn::<T>::insert(netuid, recycle_or_burn);
+    }
+
     // ========================
     // ========= Sudo =========
     // ========================

pallets/subtensor/src/utils/rate_limiting.rs

@@ -196,6 +196,7 @@ pub enum Hyperparameter {
     Yuma3Enabled = 21,
     BondsResetEnabled = 22,
     ImmuneNeuronLimit = 23,
+    RecycleOrBurn = 24,
 }
 
 impl<T: Config> Pallet<T> {