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Date: Wed, 31 Jan 2024 14:01:33 +0100
From: Christoph Hellwig <hch@lst.de>
To: Brian Foster <bfoster@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>, Jan Kara <jack@suse.cz>,
	linux-mm@kvack.org, Matthew Wilcox <willy@infradead.org>,
	Jan Kara <jack@suse.com>, David Howells <dhowells@redhat.com>,
	Christian Brauner <brauner@kernel.org>,
	"Darrick J. Wong" <djwong@kernel.org>, linux-xfs@vger.kernel.org,
	linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 19/19] writeback: simplify writeback iteration
Message-ID: <20240131130133.GA25391@lst.de>
References: <20240125085758.2393327-1-hch@lst.de> <20240125085758.2393327-20-hch@lst.de> <20240130104605.2i6mmdncuhwwwfin@quack3> <20240130141601.GA31330@lst.de> <20240130215016.npofgza5nmoxuw6m@quack3> <20240131071437.GA17336@lst.de> <ZbpCEagJOh61eH6M@bfoster>
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User-Agent: Mutt/1.5.17 (2007-11-01)

On Wed, Jan 31, 2024 at 07:50:25AM -0500, Brian Foster wrote:
> The implied field initialization via !folio feels a little wonky to me
> just because it's not clear from the client code that both fields must
> be initialized. Even though the interface is simpler, I wonder if it's
> still worth having a dumb/macro type init function that at least does
> the batch and error field initialization.
> 
> Or on second thought maybe having writeback_iter() reset *error as well
> on folio == NULL might be a little cleaner without changing the
> interface....

I like that second idea.  An initialization helper I could live with,
but if only folio needs a defined state, that seems superflous.