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Date: Mon, 5 Jul 2021 21:15:26 +0100
From: Matthew Wilcox <willy@infradead.org>
To: Gao Xiang <xiang@kernel.org>
Subject: Re: [RFC PATCH 2/2] erofs: directly traverse pages in
 z_erofs_readahead()
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References: <20210705183253.14833-1-xiang@kernel.org>
 <20210705183253.14833-2-xiang@kernel.org>
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On Tue, Jul 06, 2021 at 02:32:53AM +0800, Gao Xiang wrote:
> In that way, pages can be accessed directly with xarray.

I didn't mean "open code readahead_page()".  I meant "Wouldn't it be
great if z_erofs_do_read_page() used readahead_expand() in order to
allocate the extra pages in the extents that cover the start and end of
the requested chunk".  That way the pages would already be in the page
cache for subsequent reads.