MDEV-17441 - InnoDB transition to C++11 atomics

Replaced simple_atomic_counter with Atomic_counter.

storage/innobase/include/srv0srv.h

@@ -143,7 +143,8 @@ struct srv_stats_t
 	ulint_ctr_1_t		n_lock_wait_count;
 
 	/** Number of threads currently waiting on database locks */
-	simple_atomic_counter<>	n_lock_wait_current_count;
+	MY_ALIGNED(CACHE_LINE_SIZE) Atomic_counter<ulint>
+				n_lock_wait_current_count;
 
 	/** Number of rows read. */
 	ulint_ctr_64_t		n_rows_read;

storage/innobase/include/sync0types.h

@@ -1184,28 +1184,4 @@ struct MY_ALIGNED(CPU_LEVEL1_DCACHE_LINESIZE) simple_counter
 	/** The counter */
 	Type	m_counter;
 };
-
-/** Simple atomic counter aligned to CACHE_LINE_SIZE
-@tparam	Type	lint or ulint */
-template <typename Type = ulint>
-struct MY_ALIGNED(CPU_LEVEL1_DCACHE_LINESIZE) simple_atomic_counter
-{
-	/** Increment the counter */
-	Type inc() { return add(1); }
-	/** Decrement the counter */
-	Type dec() { return add(Type(~0)); }
-
-	/** Add to the counter
-	@param[in]	i	amount to be added
-	@return	the value of the counter before adding */
-	Type add(Type i) { return my_atomic_addlint(&m_counter, i); }
-
-	/** @return the value of the counter (non-atomic access)! */
-	operator Type() const { return m_counter; }
-
-private:
-	/** The counter */
-	Type	m_counter;
-};
-
 #endif /* sync0types_h */

storage/innobase/lock/lock0wait.cc

@@ -285,7 +285,7 @@ lock_wait_suspend_thread(
 
 	if (thr->lock_state == QUE_THR_LOCK_ROW) {
 		srv_stats.n_lock_wait_count.inc();
-		srv_stats.n_lock_wait_current_count.inc();
+		srv_stats.n_lock_wait_current_count++;
 
 		if (ut_usectime(&sec, &ms) == -1) {
 			start_time = -1;
@@ -398,7 +398,7 @@ lock_wait_suspend_thread(
 			thd_storage_lock_wait(trx->mysql_thd, diff_time);
 		}
 
-		srv_stats.n_lock_wait_current_count.dec();
+		srv_stats.n_lock_wait_current_count--;
 
 		DBUG_EXECUTE_IF("lock_instrument_slow_query_log",
 			os_thread_sleep(1000););