Fixed potential deadlock

Can't lock `m_minerLock` inside SideChain update

src/p2pool.cpp

@@ -596,13 +596,15 @@ void p2pool::submit_sidechain_block(uint32_t template_id, uint32_t nonce, uint32
 	m_blockTemplate->submit_sidechain_block(template_id, nonce, extra_nonce);
 }
 
-void p2pool::update_block_template_async()
+void p2pool::update_block_template_async(bool is_alternative_block)
 {
 	// If p2pool is stopped, m_blockTemplateAsync is most likely already closed
 	if (m_stopped) {
 		return;
 	}
 
+	m_isAlternativeBlock = is_alternative_block;
+
 	const int err = uv_async_send(&m_blockTemplateAsync);
 	if (err) {
 		LOGERR(1, "uv_async_send failed, error " << uv_err_name(err));
@@ -620,6 +622,16 @@ void p2pool::update_block_template()
 	m_blockTemplate->update(data, *m_mempool, &m_params->m_wallet);
 	stratum_on_block();
 	api_update_pool_stats();
+
+#ifdef WITH_RANDOMX
+	if (m_isAlternativeBlock.exchange(false)) {
+		MutexLock lock(m_minerLock);
+
+		if (m_miner) {
+			m_miner->reset_share_counters();
+		}
+	}
+#endif
 }
 
 void p2pool::download_block_headers(uint64_t current_height)
@@ -1373,15 +1385,6 @@ void p2pool::stop_mining()
 		m_miner = nullptr;
 	}
 }
-
-void p2pool::reset_miner()
-{
-	MutexLock lock(m_minerLock);
-
-	if (m_miner) {
-		m_miner->reset_share_counters();
-	}
-}
 #endif
 
 static void on_signal(uv_signal_t* handle, int signum)

src/p2pool.h

@@ -77,7 +77,7 @@ public:
 	void submit_block_async(const std::vector<uint8_t>& blob);
 	void submit_sidechain_block(uint32_t template_id, uint32_t nonce, uint32_t extra_nonce);
 
-	void update_block_template_async();
+	void update_block_template_async(bool is_alternative_block = false);
 	void update_block_template();
 
 	void download_block_headers(uint64_t current_height);
@@ -91,7 +91,6 @@ public:
 #ifdef WITH_RANDOMX
 	void start_mining(uint32_t threads);
 	void stop_mining();
-	void reset_miner();
 #endif
 
 	uint64_t zmq_last_active() const { return m_zmqLastActive; }
@@ -198,6 +197,8 @@ private:
 	uv_async_t m_blockTemplateAsync;
 	uv_async_t m_stopAsync;
 
+	std::atomic<bool> m_isAlternativeBlock{ false };
+
 	std::atomic<uint64_t> m_zmqLastActive;
 	uint64_t m_startTime;
 	uv_async_t m_restartZMQAsync;

src/side_chain.cpp

@@ -1539,7 +1539,7 @@ void SideChain::update_chain_tip(const PoolBlock* block)
 
 			block->m_wantBroadcast = true;
 			if (m_pool) {
-				m_pool->update_block_template_async();
+				m_pool->update_block_template_async(is_alternative);
 
 				// Reset stratum share counters when switching to an alternative chain to avoid confusion
 				if (is_alternative) {
@@ -1547,9 +1547,6 @@ void SideChain::update_chain_tip(const PoolBlock* block)
 					if (s) {
 						s->reset_share_counters();
 					}
-#ifdef WITH_RANDOMX
-					m_pool->reset_miner();
-#endif
 					LOGINFO(0, log::LightCyan() << "SYNCHRONIZED");
 				}
 			}