From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8CF021E492; Fri, 31 May 2024 14:10:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717164601; cv=none; b=Dmg9U3Dh4TNL/kxGh38dm+XpiqgbjwMuC0ibSqAM/U+ZNa9W7g8UGcHEWxKi8TTAcRh5NMQ+ki8j4030fG3jwTwCWvXMyEVOE+0idP2lT+idHMNDoP7NcL3esiyCGJJPQKyvZGi4+wx6MfdWlUHkq8D1RvUYqQ+8Jp3hFdNekLE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717164601; c=relaxed/simple; bh=6+bnziXgxwqhoOY1VvRRs5lGYHQ7FbFZYIANGvO6r24=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=gEYIOuIL1QcfPgxrvr53IXgt5eVmOINBwws4rElQ7rGd9NhCxyRA1uS+MGyHGAe1bykw+Mq9oVF23NTxKtWgVKDnGOsw23ulisYAuDIwQ9Ca3jVDhRpcPcCfYb6hHfs2zk78rKFCBUuUnenCfHmXsL77KqejruLj0XMJ7jzkQbc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=uHCGEIFO; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="uHCGEIFO" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 11902C116B1; Fri, 31 May 2024 14:10:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1717164601; bh=6+bnziXgxwqhoOY1VvRRs5lGYHQ7FbFZYIANGvO6r24=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=uHCGEIFOz4I2/6WrL6ELPQdxd5jko0EOlBJFWfb5W4ZFEpUE+TaUHQ+mRh0tmJ22i 7dP4R0TRtqPzRXAmuWNv9Iuc82Clm3TddeBYWHJzEuqtFHfelXxW2G6uWmGZbPrze1 bhj7rZT5NNYTtUaVrfKyJLw1xVhCIXWLBWwxurU6rIACfZmrjH3u018xj9IR883O+q k1j3+aD1JRuUKKMFkFaUqCQnnLpoDze28e7SNpQ+2JbN/E17UCeKcjV90mkRBkUo4a ESyDoEbgDDwNWHsyyTvCnTSZkKa7uqXQgHoIEW7vL4beeN79amXgDncFO38BIviXDy /kxPObN06vJAg== Date: Fri, 31 May 2024 07:10:00 -0700 From: "Darrick J. Wong" To: Christoph Hellwig Cc: Zhang Yi , linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, brauner@kernel.org, david@fromorbit.com, chandanbabu@kernel.org, jack@suse.cz, willy@infradead.org, yi.zhang@huawei.com, chengzhihao1@huawei.com, yukuai3@huawei.com Subject: Re: [RFC PATCH v4 7/8] xfs: reserve blocks for truncating realtime inode Message-ID: <20240531141000.GH52987@frogsfrogsfrogs> References: <20240529095206.2568162-1-yi.zhang@huaweicloud.com> <20240529095206.2568162-8-yi.zhang@huaweicloud.com> Precedence: bulk X-Mailing-List: linux-xfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Fri, May 31, 2024 at 05:42:37AM -0700, Christoph Hellwig wrote: > > - error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, 0, 0, 0, &tp); > > + resblks = XFS_IS_REALTIME_INODE(ip) ? XFS_DIOSTRAT_SPACE_RES(mp, 0) : 0; > > This probably wants a comment explaining that we need the block > reservation for bmap btree block allocations / splits that can happen > because we can split a written extent into one written and one > unwritten, while for the data fork we'll always just shorten or > remove extents. "for the data fork"? This always runs on the data fork. Did you mean "for files with alloc unit > 1 fsblock"? > I'd also find this more readable if resblks was initialized to 0, > and this became a: > > if (XFS_IS_REALTIME_INODE(ip)) > resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0); Agreed. --D