Avoid Task<MySqlDataReader> allocation on sync path.

mysql-net · Aug 13, 2023 · 016657a · 016657a
1 parent 3f5b286
commit 016657a
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Showing 3 changed files with 21 additions and 11 deletions.
diff --git a/src/MySqlConnector/Core/CommandExecutor.cs b/src/MySqlConnector/Core/CommandExecutor.cs
@@ -8,7 +8,7 @@ namespace MySqlConnector.Core;
 
 internal static class CommandExecutor
 {
-	public static async Task<MySqlDataReader> ExecuteReaderAsync(IReadOnlyList<IMySqlCommand> commands, ICommandPayloadCreator payloadCreator, CommandBehavior behavior, Activity? activity, IOBehavior ioBehavior, CancellationToken cancellationToken)
+	public static async ValueTask<MySqlDataReader> ExecuteReaderAsync(IReadOnlyList<IMySqlCommand> commands, ICommandPayloadCreator payloadCreator, CommandBehavior behavior, Activity? activity, IOBehavior ioBehavior, CancellationToken cancellationToken)
 	{
 		try
 		{

diff --git a/src/MySqlConnector/MySqlBatch.cs b/src/MySqlConnector/MySqlBatch.cs
@@ -134,7 +134,9 @@ private DbDataReader ExecuteDbDataReader(CommandBehavior behavior)
 #endif
 	{
 		this.ResetCommandTimeout();
-		return ExecuteReaderAsync(behavior, IOBehavior.Synchronous, CancellationToken.None).GetAwaiter().GetResult();
+#pragma warning disable CA2012 // OK to read .Result because the ValueTask is completed
+		return ExecuteReaderAsync(behavior, IOBehavior.Synchronous, CancellationToken.None).Result;
+#pragma warning restore CA2012
 	}
 
 #if NET6_0_OR_GREATER
@@ -148,10 +150,10 @@ private async Task<DbDataReader> ExecuteDbDataReaderAsync(CommandBehavior behavi
 		return await ExecuteReaderAsync(behavior, AsyncIOBehavior, cancellationToken).ConfigureAwait(false);
 	}
 
-	private Task<MySqlDataReader> ExecuteReaderAsync(CommandBehavior behavior, IOBehavior ioBehavior, CancellationToken cancellationToken)
+	private ValueTask<MySqlDataReader> ExecuteReaderAsync(CommandBehavior behavior, IOBehavior ioBehavior, CancellationToken cancellationToken)
 	{
 		if (!IsValid(out var exception))
-			return Task.FromException<MySqlDataReader>(exception);
+			return new ValueTask<MySqlDataReader>(Task.FromException<MySqlDataReader>(exception));
 
 		CurrentCommandBehavior = behavior;
 		foreach (MySqlBatchCommand batchCommand in BatchCommands)

diff --git a/src/MySqlConnector/MySqlCommand.cs b/src/MySqlConnector/MySqlCommand.cs
@@ -109,9 +109,11 @@ private MySqlCommand(MySqlCommand other)
 	/// <inheritdoc/>
 	public override object? ExecuteScalar() => ExecuteScalarAsync(IOBehavior.Synchronous, CancellationToken.None).GetAwaiter().GetResult();
 
-	public new MySqlDataReader ExecuteReader() => ExecuteReaderAsync(default, IOBehavior.Synchronous, default).GetAwaiter().GetResult();
+#pragma warning disable CA2012 // OK to read .Result because the ValueTask is completed
+	public new MySqlDataReader ExecuteReader() => ExecuteReaderAsync(default, IOBehavior.Synchronous, default).Result;
 
 	public new MySqlDataReader ExecuteReader(CommandBehavior commandBehavior) => ExecuteReaderAsync(commandBehavior, IOBehavior.Synchronous, default).GetAwaiter().GetResult();
+#pragma warning restore CA2012
 
 	/// <inheritdoc/>
 	public override void Prepare()
@@ -278,8 +280,10 @@ protected override DbTransaction? DbTransaction
 
 	protected override DbParameter CreateDbParameter() => new MySqlParameter();
 
+#pragma warning disable CA2012 // OK to read .Result because the ValueTask is completed
 	protected override DbDataReader ExecuteDbDataReader(CommandBehavior behavior) =>
-		ExecuteReaderAsync(behavior, IOBehavior.Synchronous, CancellationToken.None).GetAwaiter().GetResult();
+		ExecuteReaderAsync(behavior, IOBehavior.Synchronous, CancellationToken.None).Result;
+#pragma warning restore CA2012
 
 	/// <summary>
 	/// Executes this command asynchronously on the associated <see cref="MySqlConnection"/>.
@@ -332,26 +336,30 @@ internal async Task<int> ExecuteNonQueryAsync(IOBehavior ioBehavior, Cancellatio
 	}
 
 	public new Task<MySqlDataReader> ExecuteReaderAsync(CancellationToken cancellationToken = default) =>
-		ExecuteReaderAsync(default, AsyncIOBehavior, cancellationToken);
+		ExecuteReaderAsync(default, AsyncIOBehavior, cancellationToken).AsTask();
 
 	public new Task<MySqlDataReader> ExecuteReaderAsync(CommandBehavior behavior, CancellationToken cancellationToken = default) =>
-		ExecuteReaderAsync(behavior, AsyncIOBehavior, cancellationToken);
+		ExecuteReaderAsync(behavior, AsyncIOBehavior, cancellationToken).AsTask();
 
 	protected override async Task<DbDataReader> ExecuteDbDataReaderAsync(CommandBehavior behavior, CancellationToken cancellationToken) =>
 		await ExecuteReaderAsync(behavior, AsyncIOBehavior, cancellationToken).ConfigureAwait(false);
 
-	internal async Task<MySqlDataReader> ExecuteReaderAsync(CommandBehavior behavior, IOBehavior ioBehavior, CancellationToken cancellationToken)
+	internal async ValueTask<MySqlDataReader> ExecuteReaderAsync(CommandBehavior behavior, IOBehavior ioBehavior, CancellationToken cancellationToken)
 	{
 		Volatile.Write(ref m_commandTimedOut, false);
 		this.ResetCommandTimeout();
 		using var registration = ((ICancellableCommand) this).RegisterCancel(cancellationToken);
 		return await ExecuteReaderNoResetTimeoutAsync(behavior, ioBehavior, cancellationToken).ConfigureAwait(false);
 	}
 
-	internal Task<MySqlDataReader> ExecuteReaderNoResetTimeoutAsync(CommandBehavior behavior, IOBehavior ioBehavior, CancellationToken cancellationToken)
+	internal ValueTask<MySqlDataReader> ExecuteReaderNoResetTimeoutAsync(CommandBehavior behavior, IOBehavior ioBehavior, CancellationToken cancellationToken)
 	{
 		if (!IsValid(out var exception))
-			return Task.FromException<MySqlDataReader>(exception);
+#if NET5_0_OR_GREATER
+			return ValueTask.FromException<MySqlDataReader>(exception);
+#else
+			return new ValueTask<MySqlDataReader>(Task.FromException<MySqlDataReader>(exception));
+#endif
 
 		var activity = NoActivity ? null : Connection!.Session.StartActivity(ActivitySourceHelper.ExecuteActivityName,
 			ActivitySourceHelper.DatabaseStatementTagName, CommandText);