Merge bitcoin/bitcoin#24235: validation: use stronger EXCLUSIVE_LOCKS…

…_REQUIRED()

99de806 validation: use stronger EXCLUSIVE_LOCKS_REQUIRED() (Vasil Dimov)

Pull request description:

  bitcoin/bitcoin#24103 added annotations to
  denote that the callers of `CChainState::ActivateBestChain()` and
  `CChainState::InvalidateBlock()` must not own `m_chainstate_mutex` at
  the time of the call.

  Replace the added `LOCKS_EXCLUDED()` with a stronger
  `EXCLUSIVE_LOCKS_REQUIRED()`, see
  https://clang.llvm.org/docs/ThreadSafetyAnalysis.html#negative for the
  difference between both.

ACKs for top commit:
  hebasto:
    ACK 99de806.
  jonatack:
    ACK 99de806. Tested with Debian clang version 13.0.1.  Reproduced hebasto's results. Verified that  `LoadExternalBlockFile()` needs the annotation added here.

Tree-SHA512: 59640d9ad472cdb5066ecde89cc0aff8632a351fc030f39bb43800d2c856fb1aed3576e4134212d32be161b18780f06dc5066ac71df7f7cd69e3f21f886e1542

src/validation.h

@@ -597,7 +597,8 @@ class CChainState
         EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
 
     /** Import blocks from an external file */
-    void LoadExternalBlockFile(FILE* fileIn, FlatFilePos* dbp = nullptr);
+    void LoadExternalBlockFile(FILE* fileIn, FlatFilePos* dbp = nullptr)
+        EXCLUSIVE_LOCKS_REQUIRED(!m_chainstate_mutex);
 
     /**
      * Update the on-disk chain state.
@@ -639,7 +640,9 @@ class CChainState
      */
     bool ActivateBestChain(
         BlockValidationState& state,
-        std::shared_ptr<const CBlock> pblock = nullptr) LOCKS_EXCLUDED(m_chainstate_mutex, cs_main);
+        std::shared_ptr<const CBlock> pblock = nullptr)
+        EXCLUSIVE_LOCKS_REQUIRED(!m_chainstate_mutex)
+        LOCKS_EXCLUDED(::cs_main);
 
     bool AcceptBlock(const std::shared_ptr<const CBlock>& pblock, BlockValidationState& state, CBlockIndex** ppindex, bool fRequested, const FlatFilePos* dbp, bool* fNewBlock) EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 
@@ -657,9 +660,15 @@ class CChainState
      *
      * May not be called in a validationinterface callback.
      */
-    bool PreciousBlock(BlockValidationState& state, CBlockIndex* pindex) LOCKS_EXCLUDED(cs_main);
+    bool PreciousBlock(BlockValidationState& state, CBlockIndex* pindex)
+        EXCLUSIVE_LOCKS_REQUIRED(!m_chainstate_mutex)
+        LOCKS_EXCLUDED(::cs_main);
+
     /** Mark a block as invalid. */
-    bool InvalidateBlock(BlockValidationState& state, CBlockIndex* pindex) LOCKS_EXCLUDED(m_chainstate_mutex, cs_main);
+    bool InvalidateBlock(BlockValidationState& state, CBlockIndex* pindex)
+        EXCLUSIVE_LOCKS_REQUIRED(!m_chainstate_mutex)
+        LOCKS_EXCLUDED(::cs_main);
+
     /** Remove invalidity status from a block and its descendants. */
     void ResetBlockFailureFlags(CBlockIndex* pindex) EXCLUSIVE_LOCKS_REQUIRED(cs_main);