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Date:   Sat, 27 Mar 2021 13:56:59 +0000
From:   Matthew Wilcox <willy@infradead.org>
To:     David Howells <dhowells@redhat.com>
Cc:     Mike Marshall <hubcap@omnibond.com>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>
Subject: Re: [RFC PATCH v2] implement orangefs_readahead
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On Sat, Mar 27, 2021 at 08:31:38AM +0000, David Howells wrote:
> However, in Mike's orangefs_readahead_cleanup(), he could replace:
> 
> 	rcu_read_lock();
> 	xas_for_each(&xas, page, last) {
> 		page_endio(page, false, 0);
> 		put_page(page);
> 	}
> 	rcu_read_unlock();
> 
> with:
> 
> 	while ((page = readahead_page(ractl))) {
> 		page_endio(page, false, 0);
> 		put_page(page);
> 	}
> 
> maybe?

I'd rather see that than open-coded use of the XArray.  It's mildly
slower, but given that we're talking about doing I/O, probably not enough
to care about.