From 545a83efbfb6a6bd224a878f4f938e37fbc54fa0 Mon Sep 17 00:00:00 2001
From: Abtin Keshavarzian <abtink@google.com>
Date: Sat, 9 May 2026 07:32:47 -0700
Subject: [PATCH] [mlr] remove `CheckInvariants()` method (#13082)

This commit removes the `CheckInvariants()` method and all its calls
from `Mlr::Manager`.

The `CheckInvariants()` method verified internal state consistency
by checking the `kStateRegistering` status of multicast addresses
against variables like `mPending` and `mSendDelay`. As the MLR module
is being prepared for upcoming structural updates, including changes
to how address states and delays are tracked, these specific invariant
checks are no longer applicable. Removing them clears the way for
the planned redesign of the MLR state machine.
---
 src/core/thread/mlr_manager.cpp | 42 ---------------------------------
 src/core/thread/mlr_manager.hpp |  2 --
 2 files changed, 44 deletions(-)

diff --git a/src/core/thread/mlr_manager.cpp b/src/core/thread/mlr_manager.cpp
index 9e082845f..a97130f87 100644
--- a/src/core/thread/mlr_manager.cpp
+++ b/src/core/thread/mlr_manager.cpp
@@ -102,7 +102,6 @@ void Manager::UpdateLocalSubscriptions(void)
     }
 #endif
 
-    CheckInvariants();
     ScheduleSend(0);
 }
 
@@ -174,7 +173,6 @@ void Manager::UpdateProxiedSubscriptions(Child &aChild, const ChildAddressArray
 
 exit:
     LogMulticastAddresses();
-    CheckInvariants();
 
     if (aChild.HasAnyMlrToRegisterAddress())
     {
@@ -317,7 +315,6 @@ exit:
     }
 
     LogMulticastAddresses();
-    CheckInvariants();
 }
 
 #if OPENTHREAD_FTD && OPENTHREAD_CONFIG_TMF_PROXY_MLR_ENABLE && OPENTHREAD_CONFIG_COMMISSIONER_ENABLE
@@ -603,7 +600,6 @@ void Manager::Finish(bool aSuccess, const AddressArray &aFailedAddresses)
 #endif
 
     LogMulticastAddresses();
-    CheckInvariants();
 }
 
 void Manager::HandleTimeTick(void)
@@ -626,7 +622,6 @@ void Manager::Reregister(void)
     LogInfo("MLR Reregister!");
 
     SetMulticastAddressState(kStateRegistered, kStateToRegister);
-    CheckInvariants();
 
     ScheduleSend(0);
 
@@ -743,43 +738,6 @@ Error Manager::AddressArray::AddUnique(const Ip6::Address &aAddress)
     return error;
 }
 
-void Manager::CheckInvariants(void) const
-{
-#if OPENTHREAD_EXAMPLES_SIMULATION && OPENTHREAD_CONFIG_ASSERT_ENABLE
-    uint16_t registeringNum = 0;
-
-    OT_UNUSED_VARIABLE(registeringNum);
-
-    OT_ASSERT(!mPending || mSendDelay == 0);
-
-#if OPENTHREAD_CONFIG_MLR_ENABLE
-    for (Ip6::Netif::MulticastAddress &addr : Get<ThreadNetif>().GetMulticastAddresses())
-    {
-        if (addr.Matches(kStateRegistering))
-        {
-            registeringNum++;
-        }
-    }
-#endif
-#if OPENTHREAD_FTD && OPENTHREAD_CONFIG_TMF_PROXY_MLR_ENABLE
-    for (const Child &child : Get<ChildTable>().Iterate(Child::kInStateValid))
-    {
-        for (const Child::Ip6AddrEntry &addrEntry : child.GetIp6Addresses())
-        {
-            if (!addrEntry.IsMulticastLargerThanRealmLocal())
-            {
-                continue;
-            }
-
-            registeringNum += (addrEntry.GetMlrState(child) == kStateRegistering);
-        }
-    }
-#endif
-
-    OT_ASSERT(registeringNum == 0 || mPending);
-#endif // OPENTHREAD_EXAMPLES_SIMULATION
-}
-
 } // namespace Mlr
 } // namespace ot
 
diff --git a/src/core/thread/mlr_manager.hpp b/src/core/thread/mlr_manager.hpp
index 606c521c5..d9b0e12d6 100644
--- a/src/core/thread/mlr_manager.hpp
+++ b/src/core/thread/mlr_manager.hpp
@@ -201,9 +201,7 @@ private:
     void ScheduleNextRegistration(RegistrationRequest aRequest);
     void Reregister(void);
     void HandleTimeTick(void);
-
     void LogMulticastAddresses(void);
-    void CheckInvariants(void) const;
 
 #if (OPENTHREAD_FTD && OPENTHREAD_CONFIG_TMF_PROXY_MLR_ENABLE) && OPENTHREAD_CONFIG_COMMISSIONER_ENABLE
     Callback<RegisterCallback> mRegisterCallback;